Bell 206: JetRanger and LongRanger

[SierraEcho]

Hello!

Need a little advice, I'm getting type rated on the 206 (BII and BIII). The problem is that in the BIII for some reason the pedals get unbelievably stiff when the rotor is turning. It feels pretty much like someone is pushing against me all the time (nope, it's not the instructor :}).
Directional control is poor to say the least. Is this normal for the BIII model or is it some kind of rigging issue?

EDITED for cr***y spelling!

[206 jock]

Stiff pedals

Depends more on how old your BII is. The early ones had hydraulic pedal assistance as well as cyclic and collective. But in the mid 70's they did away with the pedal assist as it is frankly a bit of unnecessary luxury. It just needs firm but positive control.

So if you've done a lot of your training in the BII, then switched to the BIII, you would find the later model much less easy to control on the pedals.

[that chinese fella]

Have the engineers check the self aligning feathering bearing in the tail rotor blades. I have seen them cracked and also corroded, although the corrosion was only evident once the blades were removed and the bearings could be viewed in full by rotating them. New bearings fixed the problem.

[helonorth]

Not normal. There is something wrong with your helicopter. I wouldn't fly
it again until it get's solved.

[SierraEcho]

I do believe that the bearings were changed but I'll check that with the engineers! The BII is from '75 and the BIII from '80. When the rotors are not turning the pedals feel completely normal so the theory about hydraulic assistance might be valid! Thanx everyone! :)

[What Limits]

Hi fellow Jet Rangers

Can I ask what configuration that you think you need to be in to exceed the latest limitation

i.e. less than 60 seconds at 77 to 88% N2 with torque greater than 33%

I understood what the previous limitation meant but this one must be really difficult to exceed.

Your constructive criticism will be most welcome !!

[Phoinix]

Are you sure?

less than 60 seconds at 77 to 88% N2 with torque greater than 33%

N2 77-88%
TQ >33%


Is this the latest revision for 206B C-20J or some other model maybe?

This one will be hard to get into indeed.

[quichemech]

The parameters listed are what is stated for the C20 powered B206 as listed in the latest revision to the flight manual, B49 for B206B and I think it's revision 11 for the B206B3, the ASB associated with the parameters has been revised and the decal has also been changed as well. If you operate a Jetranger then you should have received and actioned this already.

[What Limits]

Yep, we have done that but what does it all mean?

[Sgtfrog]

I may be talking complete :mad: but I was told it was something to do with a problem the military had discovered due to the way they perform their pre-flight run up procedures.......
However, I can't remember what the issue was or why it would bother us civi types!:E
SF

[somepitch]

i could see it happening in training if you were practicing left pedal failures...maybe if you drooped the rpm a little too early and didn't get it on the ground within 60 sec?

[Phoinix]

What about Agusta Bells? When Bell issues a revision on the PFM, when or with what time lag does Agusta respond?

[GeorgeMandes]

We have just been through this with an L4 and been in touch with Bell and Rolls Royce to clarify the new procedure and limitation. As I understand it, there was an issue with the 407 that brought this about, and we now have the limitation to avoid continuous operations with this new range with the L4. Bell and Rolls Royce define continuous as longer than one minute.

You end up in this range while bringing gas generator to 70 per cent to bring the generator on-line. Previously, we stayed there while doing the preliminary hydraulics check and setting up avionics. Now, we come to 70 per cent, bring the generator on-line, and then roll back to idle. That gets us back below that range in less than a minute. When we have avionics squared away, we come up to 100 per cent for the hydraulics and anti-ice check, which causes us to move promptly thru the avoid continuous operation range. Bell is now teaching this procedure at their training academy.

We were initially concerned about having been in the avoid range for more than a minute prior to the new limitation and received the following clarification below.

George

The requirement to avoid continuous operation in the speed avoid range stems from some #3 wheel cracking issues we experienced on C47B engines operated in the Bell 407 several years ago. We have never experienced the the same #3 wheel cracks on C30P engines in Bell Longrangers BUT the #3 turbine wheel is the same part number and therefore is used in both engine/helicopter models. For this reason, the speed avoid range was applied to all C30 & C47 type engines.

In the case of the C47B, all turbines had their #3 wheels inspected in a campaign a couple years ago. Because the C30P has been around since 1976 and never had a cracking issue and we have reviewed many removed C30P #3 wheels, we have a very high degree of confidence in our decision not to make the one minute rule retroactive to wheels operated prior to the Speed Avoid Range release. This is a extra safety precaution that shall be followed from now on but we will not require it to be retroactive to past operations.
Best Regards,
Kevin P. GriggsRegional Mgr.NW USA,WCanada &JapanRolls-Royce Helicopter & Small Gas Turbine Engines
Office: 360-678-1154Fax: 360-678-0232 Cell: 360-239-9081E-Mail: [email protected]

[Phoinix]

What does this than have to do with Jetranger C20 turbines?

[206 jock]

I've done about 5 hours in my 206, since it came out of restoration which included all major components zero timed - I guess you expect running in problems! It's got a slight oil leak from the seal from the gearbox to the T/r driveshaft. I've wiped most of the oil off, but you can still see some residue in the pic below.

But while spotting the weeping, I noticed that there are three threads on the housing that don't have nuts on. Should they have? See the pic (a third one is round the back). There are no shoulders to take nuts, but what are the threads for, if they aren't supposed to have nuts on?

Thnx

http://i241.photobucket.com/albums/ff74/flyingsniffer/DSC00050.jpg

[BlenderPilot]

206JockBut while spotting the weeping, I noticed that there are three threads on the housing that don't have nuts on. Should they have? See the pic (a third one is round the back). There are no shoulders to take nuts, but what are the threads for, if they aren't supposed to have nuts on?
All are like that, if you look closely you will see that the bearing support housing doesn't have a flat area where the washer and nut seat flush against it. Don't know why it has those protruding bolts there but I can tell you that it has always been like that, my question is how many of us fly these machines for years and don't notice those missing nuts?

[Oldlae]

Weeping oil.
Are you sure it is oil, as it looks like excessive grease spreading out from the splined coupling. If the seal was leaking oil would show there. Engineers are in the habit of moving the shaft to and fro to check freedom of movement this makes the grease migrate out of the splines.

[206 jock]

It's definitely oil: you can't see in the pic, but it's welling up in the bottom of the bearing, then dribbling down and dropping off the bottom of the lower chip detector. PITA, but if that's the worst that happens in the break in, I'll consider myself lucky.

The Paravion heater wasn't working, but with a bit of judicious encouragement I managed to open the heater valve. Hot air then entered the cabin....along with 6 months of dust and s**t that were obviously in the pipes under the seat. Blew all over the chin bubbles. How I laughed!

Blender...thanks. I've flown one for 5 years and never noticed:eek:

[Oldlae]

Oil leak.
Sorry to mislead you, I can see the traces of oil, it shouldn't take much to change the seal.

[trackdirect]

Believe it or not Allison(now RR) have made the gearbox to fit multiple aircraft not just the Jetranger. There are some that use all the studs and some that don't, depending on the accessory or output fitted. Bell considered that they only needed to use three of the studs for their free wheel rear housing.(Not a heavy load bearing component)
The oil leak will probably not fix itself (wear in) there seems to be a bad batch of seals about at the moment, I went through 3 in my machine before there was no leak.

trackdirect

[tecpilot]

I´m looking for a good and well cultivated Jet Ranger immediately to buy. Europe based prefered. Any hints on PM. Thanks

[r44hopeful]

wow 1022 its taken me a whole day shift to get through, thanks boss, this search has been most informative i now feel i could just jump in a 206 an circumnavigate the world( as long as i had a lap top to cross ref when something went down, hopefully not me in it) :D thanks alot u guys for a great read

[HOSS 1]

Hello,

The company I work for has a "pet" 206L, that rarely flies. They keep up with the annuals and all inspections / maint. However, the sad fact is the thing almost never flies. And, it has been that way for the past 15 years.

I have been tasked with flying the thing for 30 minutes every "month, or so". The "or so" part often ends up being two months.

So my question is, what is the longest we should go between flights for the sake of the machine? I know in the military there are requirements to preserve some components if the machine is not flown. The helo is kept indoors, of course.

Thanks for your help.

HOSS

[perfrej]

The figure "every 14 days" pops up in my head, but I may be wrong. I try to fly the JetRanger of a friend of mine every 14 days to not have to do any conservation on it.

/p

[K48]

120 Tq

Direct from an Aircraft Operators supplement I found online by Piezon Enterprises for TH67 (I believe):
"The helicopter can be started in a maximum wind velocity of 45 knots and a maximum gust spread of 15 knots."

It goes on:
"Maximum wind for hovering is 35 knots crosswind and 30 knots tailwind"

Seems high to me.....

[The Nr Fairy]

Well, a quick spot turn - intentional or not - should sort out the crosswind/downwind limit !

[Phoinix]

I've been wondering the other day, what is the cause for Jetranger low frequency vibrations, propably MR induced, when on ground idle with wind present. I've been tought to reposition the cyclic stick into the wind and the vibrations should go away. Sometimes they go away, but sometimes no matter what you do with the cyclic, nothing helps.

What is the cause of these vibrations? Maybe the lift is produced only on one side of the rotor disc inducing "hoping" vibrations?

Thanks :ok:

[Gomer Pylot]

I think it's a complicated interaction between the wind, the rotor wash, and the balance. The easiest way to reduce the bounce is to pull just a little collective. How much is hard to say, you just have to find the sweet spot. It's usually much less than an inch.

[MR BLOHM]

206 Jock

Just seen your picture of the freewheel aft bearing housing.
The spline grease you see accumulated has been known to affect the PA Air vent on the FCU (may cause blockage, restriction ). For this reason (and I am open to correction, its been a while since i worked on a 206) it is recommended that any excess grease is cleaned off after greasing. This is assuming of course that your engine is fitted with a Bendix fuel control system.The PA vent is the circular mesh screen about 1 inch in diameter with a single split pin locking it in place. I think it is visible on the top right hand side of your photo. Even if the excess grease been cleaned some grease can still migrate for a few hours of flying. For this reason I allways had a cloth at hand while doing my check A just to give the area a quick clean and allways had a look at the vent for grease contamination.

Mr Blohm (Ex-206 mech.)

[206 jock]

Thanks Mr Blohm! Good issue to point out.

Does anyone have an insight into what is permissible maintenance that can be carried out on an N-reg 206, by the pilot? I recall that pilots can be trained to do the 50 hour airframe regrease, for example. What about the 90 day corrosion inspection?

It's not that I'm a tight-wad when it comes to paying but I'd quite like to know a bit more about 'what goes on', and it would save me flying the thing to maintenance shops. And having my todger pulled by engineers.

Northern Lights College offer a 12 hour 206 PM course, but they don't seem to have any scheduled? Anybody been/is it worth it/does it apply to N-reg's?

[Oldlae]

The CAA site is worth looking at, click on publications and search for CAP412 Light Aircraft Maintenance Schedule (Helicopters) scroll down to Section 5 para 2 which refers you to the relevant Air Navigation Order reference.

[206 jock]

Oldlae, thanks, but I'm pretty sure that the CAA regs will say @the pilot cannot touch anything'! However, as I understand it, the FAA takes a more prgmatic view of pilot maintenance on N-reg's: it's their view that I'm after?

[Oldlae]

206jock,
Don't assume, check.
It all depends on which register you are on.

[206 jock]

N-reg. It's on the N-Reg. It's an N-reg helicopter. Maintained to N-reg schedules.

I hope that's clear :hmm:

[Gomer Pylot]

If you're following FARs, is the helicopter operated under Part 91 or Part 135? It makes a difference. For non-commercial operations, see Part 43. Basically, a pilot can perform preventive maintenance only, and only on aircraft not operated commercially. Part 135 pilots can perform preventive maintenance or maintenance items approved in the company's ops specs, after documented training.

[Oldlae]

206jock,
Sorry, didn't RTFQ.

[Choppersquad]

Guys
Can you give me your advice on the L3 v the L4

power
speed
running cost
price
resale value
is it worth the extra cost.
I know i can find the spec on the web but i am looking for advice from someone who has flown the two machines.

thanks.
choppersquad.

[TJF97]

Under JAA, does it have to be an instructor who conducts the differences training for the Longranger? I've already got a Jetranger type rating, I was speaking to someone about the differences training and they seemed to think it could be done by another CPL??

TJF97

[2001ft]

Went up in a 206 JetRanger today for first time with a friend, great smooth ride

However when he dropped me off after a coffee he started the engines and black "smoke" seemed to "pop" (no sound) from the exhaust just as rotors started turning. No unusual sounds etc, but he said the engine had started quite hot.

Is this something he should be concerned about or quite common?

[tomstheword]

More than likely the engine gearbox breather spat some oil into the exhaust, happens everynow and then and you get little puffs of black smoke.

[BlenderPilot]

Went up in a 206 JetRanger today for first time with a friend, great smooth ride

However when he dropped me off after a coffee he started the engines and black "smoke" seemed to "pop" (no sound) from the exhaust just as rotors started turning. No unusual sounds etc, but he said the engine had started quite hot.

Is this something he should be concerned about or quite common?

No, it's not quite common and it could be cause of concern, when 206 engines give off smoke it usually means something, seals maybe going bad and other fun stuff.

I had a 206 engine break apart while in a hover, and the first signs of this was exactly what you are describing, the cause was a very small crack in one of the bearing supports inside the engine, one of the supports had a lubrication vein running inside of it, and when a few drops of oil started hitting the very hot turbine wheel, the thermal shock caused them to separate.

[albatross]

Can you define "quite hot"

If the engine has not been shut down for long - failure to wait for the TOT to descend to a reasonable number (< 150 C I recall - but it has been years since I flew a 206 ) before introducing fuel can lead to a "warm" start. A weak battery doesn't help.

While, I am sure, this is not the case here - pushing the starter button with the throttle at the idle stop will lead to a startled expression, lots of funny howling noises as the temp pegs, a pretty blue coloured turbine followed by a turbine change. I have never head of anyone saving the day by closing the throttle - it all happens too fast - push starter button, N1 rises - light off - funny noise - temp pegs.:mad: It's all over about that fast. No one involved will smile. :E
Fun and games will also present themselves if the ignitor CB is left out and after opening the throttle and having no light off this is suddenly noticed and the CB is pushed in instead of closing the throttle, aborting the start and waiting for all the fuel to drain out of the can before attempting another start. I saw this happen once - most impressive.:=

[woodstock1]

the pylon links maintains a relatively neutral position for the transmission, the drag link/Iso mount dampens the forward and aft inputs indused by forward flight controls. Left/ right inputs will be felt in the airframes, however these are dampened by the pylon link configeration.

[trackdirect]

Can anyone help out with an Aeronautical Accessories STC for the 206B Range extender??
Electronic copy please!!
STC SH2889SW

[SA Aviator]

Can anyone tell me the exact differences between the L3 and L4?

[Mr snakey]

can any one advise > i am buying a jet ranger with great hours on it but the tt straps and rotor hub overhaul is due for renewal >can any one advice a good place to look up and if they have had them done before >what cost were involved and the cheepest place to go, dont want to miss out on this great machine but dont want to be stung as soon as i buy it >only 82 hours left on parts .thanks:confused:

[JTobias]

Hi

This is a potential "ouch" and I mean big time.

The TT straps will need replacing every two years (or 1200 hours) whichever comes sooner. The two year interval is irresepective of whether or not you machine flies a single hour.

The TT straps will cost you approximately £7k fitted. I can get you an exact figure tomorrow, if you need it, as I had mine changed in February. Your maintenance Company can do this for you. Who are you proposing to use?

The main rotor hub can cost you anything from £10k - £50k and will depend upon the condition of the item when inspected. As far as I know the only people that can do this are Sloane Helicopters (though I could be wrong).


I purchased my JetBox 18 months ago. At the time I negotiated to buy the machine the main rotor hub was already at Sloane for overhaul. It had been sent in by the current owners at that time. They had budgeted for £12k and this was the price that had been estimated by Sloane prior to them receiving it.

The final bill was £37k and clearly came as a big shock to all.

By all means by buy the machine, but just bear it in mind.

Good luck


Joel:ok:

[rotorspin]

Agree with Joel here, TT straps will set you back 8.5k ish and then you get a credit for the old one's of approx 1.5k once Bell have them back in their hands. Bell obviously don't appreciate these parts being re-manufactured and ending up on the grey market!

Have heard similar horror stories on main rotor hub overhaul, the key to buying any Jetranger is to buy with a business head on rather than an emotional one!

There are some 206's with great component times on sale in the UK market at the moment! Ignore the hours and the year of manufacture, concentrate on spec and components (inc TT's and annuals). You will make it the machine you want it to be with a new paint, interior and avionics.

Some may say buy now before the banks continue registering profits of £3bn! But as I am not a banker I couldn't possibly comment! :cool:

[BlenderPilot]

Can anyone tell me the exact differences between the L3 and L4?

- 435 vs 490 HP, same engine but the transmission can handle more power.
- 4,150 vs 4,450 Lbs MTOW
- Slightly different fuel burn sequence with minor changes in the fuel system.
- Slightly different limitations, like in N2/NR
- Some L4's have a High Altitude Tail Rotor Kit installed.
- The L4's come with a K-Flex main driveshaft as standard equipment.
- Some L3's don't have a FWD Fuel Qty switch, although all L4's do.

I can't remember any other differences, but mainly that is it, they are almost identical, and at High DA's I would much rather go on the L3 as the L4 gets a little dangerous with the TR situation.

[DTibbals53]

Blender wrote: "at High DA's I would much rather go on the L3 as the L4 gets a little dangerous with the TR situation."

I think you have that reversed. The High Altitude TR is the fix for the LTE problem inherent with the L-1/L-3.

It is a bit more sensitive than the L-3 tail rotor, but I much prefer having the authority.

JMHO:ok:

[seriogak]

all the information about the BP 2380 can be found at BP Turbo Oil 2380 (http://www.bp-2380.com) and Mobil 2 Zhet site Mobil Jet Oil II (http://www.mobiljet2.com)

[206 jock]

My turbine recently came back from overhaul, and since then, we have an intermittent problem on start. Until the engine went away (and with my previous aircraft), as you wound up to 15% and cracked the throttle, the engine would start immediately.

Now, it sometimes 'hangs' for a second or so before firing. The resulting start is then hotter than normal, (still within limits). Of course, whenever I demonstrate it to engineers, it behaves normally and they pat me on the head and tell me to go flying, but their theories have indicated a possible prob with fuel control (don't beleive it) or cracked igniter insulation (but it apparently sounds very healthy) resulting in poor spark.

Any ideas/suggestions?

[rotorspin]

"but so far the lazy sods have not actually done anything about it."

change maintenance organisations?

[206 jock]

change maintenance organisations?

:eek::eek::ugh:

[handbag]

We had the same problem with a B3 of late. Throttle goes to idle at 15% and there was a 2 or 3 second delay to light off. After a little component swapping the conclusion was a weak battery. New one cured it.

[GoodGrief]

How about the filter IN the fuel nozzle?

But then again, after engine overhaul...

[Oldlae]

I would guess that the engineers have little to go on thus being non helpful.

[TukTuk BoomBoom]

206 Jock, how would you suggest you troubleshoot a problem that isnt there?
If there are no symptoms its a bit hard to find the defect,intermittant ones are the hardest to troubleshoot.

Why do you think it wouldnt be the FCU?
To me it sounds like the Fuel Nozzle would be a good start or even bleeding the fuel system to begin with.

Also possibility of pilot finger trouble..sometimes these problems disappear with a different pilot.
Engineers learn that the hard way!

[John Eacott]

206 jock,

Have you started using external power? If the problem is battery related, using external power should help to trouble shoot that.

[DTibbals53]

Now, it sometimes 'hangs' for a second or so before firing. The resulting start is then hotter than normal, (still within limits). Of course, whenever I demonstrate it to engineers, it behaves normally and they pat me on the head and tell me to go flying, but their theories have indicated a possible prob with fuel control (don't beleive it) or cracked igniter insulation (but it apparently sounds very healthy) resulting in poor spark..but so far the lazy sods have not actually done anything about it.

Any ideas/suggestions?

Have your mech/engineer try shimming the fuel nozzle. The plume of fuel and air mix will sometimes not make adequate contact with the ignitors, resulting in the characteristics you have outlined. Moving the nozzle fore or aft will cure this in many instances, and it does not take a lot of shim to get a positive result.:8

[206 jock]

Thanks: the battery and fuel spray patterns are good ideas. The battery is only 2 years old (NiCad), but I've had lead acid ones that have lasted much less time before now.

I'm no engineer, but the problem to me seems to be that fuel is going in as it should, and if it lights off as you crack it, the temp barely rises to the yellow line. So my supposition is that the fuel is still flowing in normally, but for whatever reason its not igniting - hence my thought that it's a problem with spark not fuel. If the start is not good, the temp rises to nearly 900 degrees - I assume fuel is still pouring in and when it lights, it's burning that extra second worth of fuel (c29ml??) too.

Not just one pilot: two of us fly the machine regularly and both see it.

[zohar]

I have a JR 206BIII and I'm experiencing the same problem for the past 2 years. I press the start button wait till 15% open my throttle and i start counting 1 2 3 seconds and then it fires up TOT between 850 - 870.

We swap every single component including the FCU and still the same problem, i called Rolls-Royce and they send me a field technician right away.

After 8 starts he removed the fuel nozzle to take a quick peek inside.
The conclusion was that the COMBUSTION LINER is too far in.

The recommendation was to remove the 1st stage nozzle shield + Combustion Liner + Outer Combustion Case and send it to the shop where they can stack them up and compare with another set.



i will have the results next week.:confused:

keep you posted

Zohar

[Tickle]

There's a YouTube video that can be seen here of what looks like a civilian Kiowa:

GB0Rwp5nmCw

Note the unusual windscreen treatment and the thick / solid tail rotorshaft cowling, plus the upturned exhausts.

I was wondering, is there an official name for this model, or a company that does it? Never seen it before.

[FH1100 Pilot]

It can be confusing. That's not a civilian ship per se, but a "public use" aircraft. Here in the U.S., Public Use is a sort of "in-between" category in which a military helicopter can be given an N-number registration and used by law enforcement or other public agencies. The interesting thing about "public use" aircraft is that they are not constrained in operation by the FAR's that we actual, genuine civilian aircraft must follow.

The aircraft in question is a demilitarized OH-58 operated by one of Florida's numerous sheriff's departments. Looks like an OH-58C, but I'm not really up on my Army models. It has an odd mix of components in the drivetrain, from the military (i.e. olive drab) push-pull tubes to the civilian-looking mast and grips. Looks like civilian tail rotor blades too. Then again, you can never tell. There are shops that specialize in converting such aircraft from military to public use. Who knows what components get stuck on in the transition?

Someone once told me that OH-58C's *can* be converted to civilian - or Normal - category, but not the earlier -58's. Don't know why, or if that's even true. Doesn't matter though. By the time you did the conversion, the cost would be close to what a "real" 206 would go for in today's market.

[Gomer Pylot]

BlenderPilot is correct about the high-altitude t/r problems, if the high-altitude tail rotor hasn't been installed. The tail rotor on the straight L was just about adequate. Put the same rotor on an L1, with more power, and it's getting flaky. Add a C30 engine, in an L3, and it's less than adequate. Make it an L3 Increased Horsepower, or an L4, and it's dangerous. Keep on adding horsepower without increasing the tail rotor or the arm, and you'll eventually run out of tail rotor authority. The high-altitude tail rotor should be required on L3s as well as L4s, and I think it's criminal of Bell to ignore the problem.

[CyclicRick]

I have to heartily agree with the last post (no bugle please). I've run out of pedal and lost TRA a couple of times in an L3 especially when fairly heavy mostly during film/photo work when things get slow and tight. Dreadfully weak TR, I'm really surprised that they haven't tackled this way before now. Have a look at the 407, the TR didn't grow with that model either by the look of it
Rick

[blackhand]

I've run out of pedal and lost TRA a couple of times in an L3

L1 C30P and L3 operate in PNG to fairly high altitudes.
Can get into 10 to 11 thousand feet with upto 2 X 200Litre drums of fuel on the line without LTE occurring.
Suggest you get TR control rigging checked for full left travel, carry out PAC to ensure engine is performing, perhaps assess your technique.

Have a look at the 407, the TR didn't grow with that model either by the look of it

mmmmm perhaps you would like to have another look yourself, I'm looking at S.No 538xx and it has a completely different TR hub and blade assembly from the 206 series

Put the same rotor on an L1, with more power, and it's getting flaky. Add a C30 engine, in an L3, and it's less than adequate.

The L has a smaller TR than the standard L1 which inturn has a smaller TR diam than the L1C30P ( ASI or PHI STC) and L3.

Cheers
Blackhand

[Saint Jack]

Another tell-tale sign that this is a non-commercial model is the absense of tail rotor gearbox fairings.

[BlenderPilot]

DTibbals53
Blender wrote: "at High DA's I would much rather go on the L3 as the L4 gets a little dangerous with the TR situation."

I think you have that reversed. The High Altitude TR is the fix for the LTE problem inherent with the L-1/L-3.

It is a bit more sensitive than the L-3 tail rotor, but I much prefer having the authority.

JMHO

Dear DT,

What I meant is that I WITHOUT the High Altitude Tail Rotor Kit, which is OPTIONAL on the L3 and L4, at altitude, say 10K DA, I would rather be in an L3 over an L4, even if the latter has more power.

The L4 has more power, but at altitude you cannot use it safely as the TR does not have enough authority to counteract torque at high power settings, if you are in an L4 say at 8,000 feet with a DA of 10 or 11 thousand, you can be pulling around 75-80% torque at a hover, but you will have the pedal about an inch or less from the stop, imagine in this situation what would happen if you takeoff from an elevated helipad and pull just a little more power?

You will spin! and have no way to stop the spin other than reducing power, or diving for airspeed! I really hate that!!! So that is why I prefer the L3 over the L4 even if the L3 has less power, it's just more controllable.

Unfortunately the most L4's do not have the High Altitude Tail Rotor Kit installed, since it's an expesive option which you don't get to enjoy unless you fly at altitude.

You mentioned that the optional Kit is Bells solution to the L1 and L3, but it's more for the L3 or L4 and it makes no sense to be installed on the L1, because the L1 has little power thus the TR can handle the job given, since there is less torque to counteract.

Regards

[DTibbals53]

Blender Pilot,

I will buy that explanation, with one exception.

You stated: "You mentioned that the optional Kit is Bells solution to the L1 and L3, but it's more for the L3 or L4 and it makes no sense to be installed on the L1, because the L1 has little power thus the TR can handle the job given, since there is less torque to counteract."

In our company, the L-1s and L-3s have the same engines nowdays, and thus the problem persists in the entire L series. Doomed to the wild ride if attention is not adequately applied at the appropriate times.

Good conversation! Poor design!:mad:

d

[birrddog]

Anyone know of a good source for comparisons between the various JetRanger and LongRanger models?

I am referring to things like nuances between the various models, operating costs, fuel burn, limitations, maintenance issues or anything else a prospective purchaser should consider.

If nothing like the above exists, I would appreciate any items I could put in a template and research. (I have access to the respective POH's from Bell for the basics).

Thanks in advance
Birrddog

[Choppersquad]

AB 206 owners
has anyone received a request for new set of publications for maintenance manuals under the new agusta -westland company for the AB 206 .we are told the old AB manuals can not be used.the cost of replacement as follows

title f.m.ab206jriii/c20/c20j 3 years revision 366 euro plus base issue 104 euro
title ab206a/b-ipc 3 year revision 1,105.00 euro plus base issue 532 euro
title ab206a /b series-mm as same 1,039.00 plus base issue 519 euro

total for the above including shipment 3591.00
is this the same cost for bell 206 owners as the above seems very high.It is a cost we could do without ,are AB owners sharing manauls to reduse cost ??


Any comments
choppersquad.

[Saint Jack]

birrddog: Perhaps a good place to start would be getting hold of the 'Product Data' books for each model you're considering. These are available from the Bell website (for current models only) and for the others you'll have to ask around for, your local Bell CSR and CSF will help you with this. These books have a wealth of information in them and will certainly get started.

If you're thinking of purchasing more than one of the 206 Series keep in mind that there is very little commonality in parts between the JetRanger and LongRanger and this includes the special tooling, particularly with the engines. Of course things like hardware are common and also avionics if you select carefully. However, if you have a JetRanger and a LongRanger you'll find yourself having to stock airframe and engine items for both types.

There are no real maintenance issues with either model and any reasonably competant mechanic will have no difficulty with them. Perhaps the only bugbear is accessibility to the rotor brake on the LongRanger otherwise they're fine.

Similarly, pilots have no difficulties crossing-over between models and perhaps the only thing they'll notice is the slight twitch at +/- 91 knots (increasing) in the LongRanger when the vertical fin effectiveness overcomes the lower-speed effectiveness of the auxiliary fins (on the ends of the horizontal stabilizer). Perhaps the most important thing a pilot has to remember in a LongRanger is to pull the L/H fuel boost pump circuit breaker after every flight - regardless of the battery switch position.

Oh, and one more thing, if the low-level fuel caution light illuminates in a LongRanger with an apparant ample amount of fuel indicated, believe the light NOT the guage.

[helipan]

Hi all,
just looking for a diagram or a photo to showing how to open the front and back doors of a Jet ranger from the inside (for a safety breifing board)
thanks in advance

[Saint Jack]

Helipan: You'll need to be more specific. The early JetRangers had 'non-slamable' doors that, from the inside, had to be held in the closed position while twisting the handle to lock them. Later JetRangers (sorry, I can't remember the S/N break) had 'slamable' doors that, again from the inside, could be pulled (slammed) closed and then push down on the lock/unlock lever to lock.

For both types of doors DO NOT allow people to slam them with the handle/lever in the locked position

[helipan]

Thanks Saint Jock,
I now know why i have a diagram thats got nothing to do with the early Jet Ranger,
It is the one with the doors that you need to turn the handles to close the doors.
From memory: in the front I think they turn clockwise to close and anticlockwise to open. with the back its the other way.....?

[Saint Jack]

helipan: I've been in the front and back seats of early JetRangers a million times (well, a lot anyway) and I simply don't remember the 'D' shaped handles operating in the opposite sense between front and rear. I'll be visiting a operator later in October who have some early 206's and I'll look out for this. Amazing isn't it, you think you know an aircraft well (I've had it on my licenced for 34 years) and something like this comes up and stumps you.

Perhaps the best way to get a diagram will be to go through the MM or IPC and pick the best one/s. There will be a page which shows the decals associated with the handles, i.e. the 'arrows' for correct direction plus 'lock' and 'unlock'. They are in place aren't they? They do get ereased and this is the kind of thing (mandatory/safety markings) that surveyors and auditors like to pounce on. Good luck

[FH1100 Pilot]

Ahh, Bell logic. Let's talk about doors.

Early JR doors certainly are "slammable" in a sense. If the outside handle is pulled out to the detent, you *should* be able to push the door closed and have it latch without having to do anything else. Then you push the outside handle in, or secure the inside handle to the horizontal position and awaaaaay you go!

However, as the airframe ages and the doors bend and linkages go out of adjustment, they don't all work that way.

From the inside, it gets confusing. Most people do turn the D-ring to the fully-unlatched position to get the door to close - which usually means they have to try a couple of times. Slam it harder this time! Reason is because if they are sitting right next to the door it is hard to get the proper leverage on it, even with the wedge windows. And! Pulling while holding the handle in even a slightly locked position will prevent the door from latching. So most passengers turn the handle while closing the door. But which way!

I tell my passengers (back seat and front) to "Lift the REAR of the handle to open the door." That works. Nevermind the clockwise/anti-clockwise stuff. It'll just confuse them. Because the left and right sides are different. On the left side you turn clockwise to open. On the right side you turn counter-clockwise to open. Does that make ANY sense? Nope. But that's our Bell Helicopter Corp. (The front and back doors on the same side work the same way, to clear up a bit of confusion in the preceding couple of posts.)

Later B-models did away with the D-ring. Instead, Bell mounted a little grab handle at about mid-point fore-and-aft on the door. Theoretically, you left the latch handle in the "open" position (at the detent), then pulled the door closed with the grab handle, then latched the door completely. (Bell added a second, upper pin to the door around this point, but the upper pin is completely retracted with the latch handle at the open detent and only comes into play when the handle is fully closed.)

Certain later model 206B's I flew at PHI had both the pull-handle *and* D-rings. Belt and suspenders!

Oh, and another bit of trivia about the old D-ring latches (and the non-D-ring latches too): They WILL open and unlatch the door if you turn them the "wrong" way. How many other 206B pilots have shut down and then opened their back doors only to see the D-ring turned wrong-way-round and at some wierd angle? I certainly have. Use enough force and you can open the door whichever way you turn the handle.

Solution? There is no solution. I never let my passengers "hot-load" themselves. Me, I get out and load them (yes, even with the engine running and yes I know that's a subject for another thread). With the door still open, I *show* them how the inside door latch works. "Open. Closed. To open it, lift up on the BACK of the handle. See? Got it? Good." They still screw it up sometimes because people are stupid and have "more important" things to worry about than some arcane aircraft bullcrap.

Oh, and by the way, when you're sitting beside the door you cannot see those cute little instructional decals Bell many people put on the door to tell passengers how to open it. The decal should more properly be on the bulkhead between the front and back seats, right in front of that particular passenger. And there should be two of them, one for each side.

Aren't 206's great?

[Saint Jack]

FH1100 Pilot: Yes, all that and more. Early JetRangers did not have rain gutters above the doors (although they were standard on Agusta models from No. 1) and when it rained whichever shoulder was nearest the door got soaked. These early models also had the cabin fresh air intake at the front of the transmission fairing and louvres above the front occupants. Again when it rained your other shoulder also got soaked. If the transmission deck wasn't sealed properly, the rainwater could seep into the circuit breaker panel with interesting results.

For those out there that really, really remember the early 206A's you'll recall the retractable handle in the vertical fin to assist ground handling and the early main rotor masts that had a increased diameter just below the hub that was to have been splined to accept a stabilizer bar like the Model 47 (early flight tests showed it wasn't necessary). How about the mechanical, yes mechanical voltage regulators.

Yup, aren't 206's great?

[FH1100 Pilot]

LOL, Saint Jack, you must be as old as me! I'd forgotten about a lot of that stuff. Like the retractable ground handling handle in the fin! Invented obviously before they thought up the high-skid gear. Anyone else ever taken a stinger to the nuts?
If the transmission deck wasn't sealed properly, the rainwater could seep into the circuit breaker panel with interesting results.
Heyyyy, mine *still* does that! I have never - ever - flown a 206 in rain that did not leak on me somewhere. First time I saw water dripping *through* a circuit breaker (which was a long time ago) was...umm..."mildly disturbing." Now, not so much. It's a 206.

[SASless]

I wonder if any Bell Engineers (I use the term loosely here) ever in their life saw a BO or BK door? If they did....would they be able to comprehend the noticeable advantages the German's have in commonsense, engineering, and cognative abilities?

[Gomer Pylot]

I have never flown in any model helicopter that didn't leak. Not one. 206, 212, 412, S76, ad infinitum, they all leak buckets into the cockpit. The water pouring from the breakers isn't so bad in a 206, but when you're in solid IMC, with weather at minimums at the beach, and barely enough fuel to get there, it's worse. If you have a very good relationship with the maintenance monkeys, and they know their stuff, you can get much of it stopped through the judicious use of proseal and silicone RTV, but you can never get it all stopped. The eyebrow vents above the windshields in the S76 are the worst, because they catch the rain and funnel it to your shoulders or crotch. The only way to stop it is to proseal the vents shut, but then somebody comes along and wants more air, although those vents only allow in a gentle breeze, even if they do allow a tsunami of water, and they break the seals, and you get wet the next time it rains.

You can buy a cheap Yugo that never leaks, but a multimillion dollar aircraft? Leaks every time. :ugh:

[Saint Jack]

Gomer Pylot: "...the maintenance monkeys...and they know their stuff" a slight contradiction of terms there - but I know what you mean. To take up the theme that SASless commented on, yes it does seem that Europeans know how to make helicopter doors watertight. Back in the early '80's when the Republic of Singapore Air Force bought the Super Puma they were assembled from kits at Seletar Air Base. Completed fuselages were pushed under a metal frame contraption that had a multitude of water nozzles spraying from all angles. The fuselage had to be watertight or it wasn't accepted - simple as that. The water rig is still there but looking a bit the worse for wear.

Incidently, and a slight drift here, I've seen C130's with the title 'Republic of Singapore Air Force' and others with 'Republic of Singapore Airforce'. I don't know which is 'correct' or how the 'other one' got there. Nothing really, I'd just thought I'd mention it as it seems very untypical of Singapore's reputed overall efficiency.

[poppahymen]

Simply by bringing the neck of the filler cap up to roughly the top of the tank it allows you to fill right to the top.

[bugdriver]

Touched on briefly earlier in this thread, but I am looking for the reason for the 2 minute cool down period before shutdown on the Allison/RR 250. I understand it's to cool the bearings to prevent coking, but which bearings, and what will eventually happen if the engine is frequently shutdown without the 2 minute cool down?

The main reason for asking is a couple of other pilots flying the same machine I fly almost always shut down early, and then I have to go put my butt in the machine and hope nothing is amiss!:uhoh:

[Brilliant Stuff]

From what I seem to remember from my long and distant days of operating the 206 it will "only" mean higher maintenance bills but I don't think the aircraft will quit on you.

I was once told that Robert Maxwell would not allow his pilot to cool his Allisons on his 355 and this meant higher maintenance bills.

But I stand corrected.

What would irk me is knowing I am flying a machine I know other pilots are not operating within the FLM. Any chance you could point out to them the error in their ways?

[Matari]

Please do your 2 minute cool-downs. If not, coke will form in the turbine rotor lubricating oil passages, and eventually starve the bearings of oil. It's been a while but I think on the 100-hr. inspections we would remove the oil sump at the bottom of the turbine rotor (it looks like a silver box about the size of a cigarette pack), and using a mirror look up inside the oil passage for coke.

We could always tell when the cool-downs were not done. The coke forms easily and the diameter of the oil passage gets smaller and smaller (much like a clogged artery, I suppose).

Will the engine quit? If not caught and cleaned on the 100-hr. inspection, then coke builds and could lead to bearing failure. Chip lights are meant to warn you, but by then it is too late to prevent the expensive repair bill.

[Hughes500]

And people wonder why engines fail, I am in shock that people play scant disregard for the one thing that keeps them aloft and all for saving 2 mins:ugh:
Mind you yesterday a chief engineer of a large maintainence company flew a piston engine machine in to where I was and it was shut down within a minute !

[John Eacott]

bugdriver,

There's a labyrinth seal that can coke up, much as Matari has said, if the 2 minute cool down is not observed. We had this discussion long and often over the years with Bell and with Allison reps, mainly relating to the temperature of the oil as against a set time. Allison have a graph somewhere to prove their requirement that the time (2 minutes) is paramount: I probably have a copy SomeWhere, but don't expect me to find it! Anyway, 2 (two) minutes shut down is mandatory, no more, no less :ok:

It can also be worth turning the blades 'backwards' when you tie them down, to break up any carbon starting to build up within the engine bearings. Sounds strange, but a lot of us 'oldies' do it as a matter of course: just a bit of old wisdom to pass on ;)

[Ready2Fly]

Turning the blades backwards (as if done forward you'd only turn the freewheel unit, not the turbine) after every flight was part of my training for the typerating. Also where i did my CPL afterwards it was normal to do this for at least one full turn after every flight (maybe that was because i learned from people being in the industry for a long time but i think this is just SOP ;) )

The machine i fly recently did build up coke and it was dealt with (read: expensive but as we noticed it in time, not too expensive). This was not due to not taking care of 2 mins cooldown but because of a weak seal, though.

You will notice when coke builds up as you will have difficulties turning your blades backward before the first flight of the day (you do turn the blades by 90 degrees to be sure they are not tied down anymore...? If so, why not turning them backwards - will tell you something if there is something wrong). Here, with N2 being stuck (i.e. you won't be able to turn the turbine wheels by hand through the exhaust pipe) you would need a bit more force to turn the rotor backward after loosening the tie-down. You could also notice that you are probably going to meet a problem when your rotor is hardly turning by 25% N1 in such a case. Still, even it it does, there might be coke built up as with us it started turning at around 20% N1 all the time.

Watch out for these little hints as they will almost always try to tell you something. And the sooner you deal with it, the less expensive it will get.

Beside all this and rule No. 1: Do, what your FM tells you to do and deal with those who don't.

[Saint Jack]

There has been a lot of discussion on this subject here and wherever 206 pilots gather, so let me explain in detail how it all originated. John Eacott's post is excellent good but leaves out a few pertinent points.
The first JetRangers were fitted with 250-C18 engines, unfortunately their reliability was not nearly as good as it is today. So in the late 60' or early 70's, the manufacturer, DDA (Detroit Diesel Allison, a Division of General Motors) developed a whole range of modifications to address this reliability issue, DDA called this the 'Blue Ribbon Program'. Subsequently, engines that incorporated all of the modifications were known as 'Blue Ribbon Engines'. This term only applied to C18 engines, the modifications were standard on all subsequent engine models.

Briefly, the modifications relating to the 2-minute dwell time were to prevent coking and seizure of the labyrinth seals, not so much the bearings, and were as follows:

1. A check valve was fitted into the oil pressure tube supplying the No's 6 and 7 bearings in the turbine module. It can be seen on the R/H side of the engine attached to the horizontal firewall and just above the FCU. This check valve closes during the last few seconds following shut-down preventing oil getting into the bearing housing. The oil scavenge pumps continue to run and this minimizes the amount of oil in the bearing housing immediately following shut-down.

2. A small stainless steel sump was fitted to the bottom of the turbine casing to allow any residual oil, again from the No's 6 and 7 bearing, to flow down and collect in there after shut-down rather than remain in the bearing housing and turn to coke under the high residual temperature. This coking would cause the rotating and non-rotating blades of the labyrinth seals to lock preventing subsequent rotation.

3. A procedure was introduced that required pilot, after landing, to observe a 2-minute dwell time between rolling the throttle to flight-idle and shut-off. As John Eacott correctly points out, this results in a significant temperature reduction in turbine module as a whole and the bearings/seals in particular. Yes, there is a DDA-produced graph somewhere showing the temperature reduction and it's quite startling.

4. Another procedure was introduced that required the main rotor to be turned backwards for three revolutions immediately after shut-down (use the main rotor tie-down but be careful not to get it wrapped around the tail rotor blades - those who've done that will know what I mean). By turning the rotor backwards the freewheel unit is engaged and the N2 section of the engine is rotated, also backwards but a lot more than three revolutions. This rotation scrapes any potential coke from the labyrinth seals.

Frankly, I've always thought that there should have been a fifth item here. DDA should have specified which oils were more susceptible to coking, not by mil-spec but by brand name. For example, I believe that anyone who uses Aeroshell 500 oil in a 250 Series engines ought to be flogged. Use this oil and your asking for trouble, use Mobil Jet Oil II instead.

To clear up a couple of misconceptions the some seem to have regarding this issue:

A. Any carbon deposits in the oil will be found in the filter/s, not on the magnetic plugs.

B. Excessive carbon build-up on a labyrinth seal will not cause an in-flight failure, but it may very well prevent a subsequent start.

So now you can see that there are very sound reasons why ALL pilots should observe the 2-minute dwell time after landing and rotate the main rotor backwards three revolutions after it's stopped - that's TWO minutes and THREE revolutions - failure to do these simple tasks WILL eventually cost you a lot of money - now you know.

[John Eacott]

SJ,

I forgot the oil type issue: thanks for the reminder! Whilst Jet II is the most common used in 206's, I swapped to Shell 560 some years back (in common with my 117) as a '3rd Generation' oil. The anti coking qualities are another stage better than Jet II, certainly quantifiable in the LTS101 as the pressure differential check showed a halving compared to 2nd generation oils used previously.

Googling for the Allison 2 minute temperature chart hasn't borne fruit yet, but I did find this (http://www.mdhelicopters.com/publications/pdf/500storage/letters/hl049.pdf) Hughes Service Information letter, with further reference to the practice of turning the blades backwards. It also has an excellent diagram of the areas likely to encounter coking, and the labyrinth seal area, on the last two pages.

[that chinese fella]

Hi,

Personally from my engineering experience I think the relative merit of the 'turning the blades backwards' has reduced on C20B/J if, as John says, 3rd generation 'HTS' oil (Mobil 254) is used, a Facet scavenge oil filter is fitted and strict adherence to the 2 minute cooldown is followed. As a pilot I still do it out of habit but I rarely see any coke build up in the 6/7 strut anymore.

Of far more importance is ensuring engineers actually pull the strut out at the stated interval, regardless of the oil flow figure, and give it a clean.

The graph you all refer to actually shows that it is closer to 1 min 45 secs before the core temperature stabilises, but 2 minutes is take as the figure published in the FM.

Now, C20R's in those stinky 5ooER's are a different story!

TCF

[Ready2Fly]

SJ,

interesting read, thx for the background :ok:

(btw here it is a C20R in our B206)

Now, if that CSL ist for 250-C20B, does anybody flying a BO-105 do the same? I mean, 2 min cooldown for sure but i never saw anybody turning the rotor of a BO-105 backwards after flight... :rolleyes:

[rick1128]

John E. I kind of curious where you can up with the 2 minutes, no more or less. The training material I have from Allison/RR on the C20's and 30's states 2 minutes minimum. However there are a few FAA types here that go with your statement and say we must reheat the engine up and then do a 2 min. coll down if we exceed the 2 minutes.

[Phil77]

Anyway, 2 (two) minutes shut down is mandatory, no more, no less

Just talked to our DOM about that, he seems to remember that 'they' said, that if you want to do good and exceed the 2 minutes and make it, let's say 5, the process tends to reverses itself and does more harm than good.

[Gomer Pylot]

Rolls-Royce says that 2 minutes is optimum, but a few seconds more or less is OK. 90 seconds is pretty much the minimum, but more is better, up to 120. If you go much beyond 2 minutes, you're supposed to go to 100%N2 for 2 minutes, then cool down again for 2 minutes. At least that's what our maintenance says, and I've heard this repeatedly. Like John, Google has been unhelpful on this.

[John Eacott]

I kind of curious where you can up with the 2 minutes, no more or less.

Rick,

20+ years ago, not too sure now! It would most likely come from the DDAllison manuals, but I don't have access to one.

There are numerous little gems hidden away like this. Going off the current discussion, where would you look within Bell's manuals for a reference that prohibits having the standard door steps fitted on a 206 if sling loading with high skids? Flight manual: yes, but where? Normal procedures, no: cargo hook supplement, no: high skid supplement: yes!

Where do you find reference in Agusta's A109 manuals to inform a pilot that the last shutdown of the day must not use the rotorbrake since it will then give a false MGB oil level? Flight manual: no. Maintenance manual: yes!

I think the 206 high skid supplement may have been amended, but it was one of those examples that I'm trying to make. Not all these gems are easily referenced, but they are usually there somewhere :ok:



that chinese fellow:

We changed to BP 2380 on the 117, when we found that our engineering advice to use Shell 560 was in direct contravention of the Maintenance Manual prohibiting the use of 560 in LTS101's :hmm:

On the 206, however, 560 is the a 3rd generation oil that is approved for both the engine and the gearbox, which is important if there is a seal leak and oil mixing. Another little point that is sometimes missed ;)

[that chinese fella]

Oil Mixing - another little 'gem' - hidden away in the depth's of the FM is a section detailing lubricants and Mobil Jet II and 254 are compatible so whilst IMHO not preferrred to constantly mix oils, there are some instances where knowledge of the 'compatabilities' may get you out a 'oil shortage' situation.

Some people swear that Mobil 254 makes gearbox seals leak, I agree that if you change over mid life with the same seals fitted then I have seen that to be true but if, say post overhaul (where new seals are fitted), you start on 254 I have witnessed no more leakage than usual from Bell gearboxes.

FWIW, our 105LS uses 254 in everything - engines, gearboxes and main rotor hub. I have been told that turning the blades backwards on the 105 is bad for the hyd pumps, but have not confirmed it - anyone have any 'offical' advice on this one?

[bugdriver]

Thank you all for your advice on the 2 min cool down.

I have been turning the blades backwards after shutdown for years, good to know it is doing some good.

The engineers have been alerted and will pay close attention!

Another question now:

Is it harmful to let the aircraft run at idle for extended periods? One client requires that the aircraft remain running while the technicians work on Volcano sensing sites, in case we have to depart in a hurry!

Thanks in advance.

Bugdriver

[Gomer Pylot]

It's supposedly not harmful, provided you go to 100% for awhile, then recool for 2 minutes before shutting down. We idle for extended periods at accident scenes while the med crews are preparing the patient. No one, including RR, has said that's a problem, as long as the proper shutdown procedures are followed, or the aircraft isn't shut down.

[bugdriver]

Thanks for that clarification Gomer.

[rotorrookie]

Does anyone remember what was included when upgrading Bell 206 L1 C-28 to C-30 engine?
I know it needed rotorhead certified for higher AUW .
Is the mast the same?
Can you use same gearbox?
What about the rest of the drivetrain and the tailboom?
And after it basically has an L3 performance right???

[blackhand]

Installation of Detroit Diesel Allison 250-C30P turboshaft engine and associated airframe and tail rotor control modifications similar to the Model 206L-3 in accordance with Air Services International FAA Sealed Master Drawing List, ASI Installation Manual, and ASI-206L-1-FM Flight Manual FAA approved April 6, 1982, or later FAA approved revisions as required as part of this modification.

Like this???

Cheers
Blackhand

[FH1100 Pilot]

If all you want to do is fly your L-1 at the L-3 MGW of 4150, then just bolt on a set of 206-11-149-101 grips/yokes and you're good to go with only an RFM supplement. (I would imagine that there's not an L-1 in all the land that hasn't been so converted.)

If you can get ahold of Bell 206 Service Instruction BHT-206-SI-2050 it will give you the details of what must be done to install the C-30P and convert an L-1 into a gen-u-wine L-3.

Then, if you really wanna go hog-wild, there is also apparently a Service Instruction to turn both an L-1 and L-3 into an L-4 (BHT-206-SI-2052) with a 4450 internal gross weight. Procure both of those SI's and you'' get all the poop.

At low altitudes, there's really no advantage to converting an L-1 to an L-3...IN ME HUMBLED O'PINION. I flew both, side by side at PHI for a long time. The lighter L-1 would perform just as well as an L-3 while burning slightly less fuel. Your mileage may vary, depending on what you're doing with it and at what density altitude. Of course, the L-3 typically ran cooler, and obviously had much more TOT "to spare" for work at higher altitudes.

[rotorrookie]

Thanks guys, I check on it at bell web:ok:
At low altitudes, there's really no advantage to converting an L-1 to an L-3
Well there is one, you dont have to clean the tailboom twice a week like with the C-28:)

[Chris P Bacon]

Rolls Royce released a "Technical variance" a while back to allow a larger clearance at the power turbine seal. This was very successful especially on the C20R in the 500's and the larger clearance has now been written into the overhaul manual.
The main problem I have experienced with 3rd generation HTS oils in the 250 engine is there tendancy to cause either oil leaks or smoking at shutdown. As the oil is a lot thinner when hot, it tends to get down the tightest threads until they turbine cools down. Light smoking which starts a couple of seconds after the turbine stops turning is normally due to this rather than the #5 bellows seal. Don't forget though, if you change over from something like Aeroshell 500 to an HTS oil, don't do it all at once and use the top off method. You will dislodge built up carbon which may block up a oil jet.

[Gomer Pylot]

There is also an increased horsepower kit for the L3, which includes, among other things, a torque gauge in which the yellow range goes to 104.8%. This gives the allowed power of the L4, but doesn't increase the allowed MGW. It can be very useful for coming out of confined areas in the summer at MGW.

[Bell_Flyer]

That is very interesting Gomer. Will you get the additional 300 pounds lift capacity that the L4 has over the L3, effectively?

Then, if you really wanna go hog-wild, there is also apparently a Service Instruction to turn both an L-1 and L-3 into an L-4 (BHT-206-SI-2052) with a 4450 internal gross weight

I believe this conversion is so expensive that it makes no economic sense to convert to an L4. Does anyone know of a conversion that has happened and the costs to the operator?

[birrddog]

The Bell rep I spoke to gave me an "estimated" number of between $500k and $750k.

The "uplift" installing the above was more than the price difference to get a second-hand 407.... (~$865k hull value L3)

[rotorrookie]

that is bloody expensive 300lbs of payload..... when you compair it to you would get about 100lbs of gold for the same amount of money hahaha

[that chinese fella]

The increased torque limitations on the L3, via a remarked torque indicator, comes complete with a requirement to conduct the transmission sungear inspection at the significantly lower interval of 600 hrs.

Out of interest, who out there utilises the Increased MAUW in the Jetranger via the FMS (cant remember the number - maybe 39?) - again, with a 'minor' caveat of reduced IAS until the fuel burn brings the AUW down to the standard internal MAUW figure. Here in OZ, I cant imagine too many people using it, most would be TOT limited anyway at higher OAT/DA.

[Gomer Pylot]

No, you don't get increased max gross weight, you just get more available torque for takeoff. It involves much more than a different torquemeter, and there are no increased inspection intervals that I'm aware of. There are a number of enhancements for the L series, involving different changes, depending on your budget and requirements. You can go all the way to complete L4 specs if you want and can afford it.

I believe Air Evac is doing that in the US, in addition to buying some new L4s.

[Bell_Flyer]

The L4's and 407's are priced very similarly - can't see why you would want an L4 unless hangar space and/or the slightly higher running costs are a problem. The 407 lifts more, flies faster, etc. Air Evac must have their economic reasons to convert to L4's.

We looked at converting B to BA, BA to B2 and then also to the Honeywell conversion kit for the AS350's. All were cheaper than the L3 to L4 conversion. Makes you wonder what Bell were thinking - maybe they need the extra dough to subsidise their bad decisions elsewhere, OR they are trying to kill off the L4?

[birrddog]

An operator I use occasionally says the L4 has better max gross weight lifting ability at high altitude because of the larger rotor blades.

[Gomer Pylot]

Bell had already killed the L4. The production line was closed several years ago, and they reopened it for the Air Evac production run. The 407 is much more expensive to operate than a 206, especially considering that Air Evac already operates more than 80 206s, and the continuing tailboom problems make the 407 questionable, IMO.

[GeorgeMandes]

What are the 407's continuing tail boom problems?

[206 jock]

Odd starting characteristic
My turbine recently came back from overhaul, and since then, we have an intermittent problem on start. Until the engine went away (and with my previous aircraft), as you wound up to 15% and cracked the throttle, the engine would start immediately.

Now, it sometimes 'hangs' for a second or so before firing. The resulting start is then hotter than normal, (still within limits). Of course, whenever I demonstrate it to engineers, it behaves normally and they pat me on the head and tell me to go flying, but their theories have indicated a possible prob with fuel control (don't beleive it) or cracked igniter insulation (but it apparently sounds very healthy) resulting in poor spark.

So, in the meantime, the engineers have changed the start characteristics so it's now slower and the double peak much more prominent, until they can really get to the bottom of the problem at the annual.

Current situation? Aircraft is now sat on the tarmac at Brussels International with a complete failure to start! Press the starter...tick tick tick...15%...open the throttle....nothing!

Why do aircraft always choose the best times to throw their toys out?

Anyone know any good local 206 engineers to save me sending my lot from the UK? Have tried Heli service Belgium and they told me to call back on Monday......

[Gomer Pylot]

The 407 has cracking problems, especially around the horizontal stabilizer, and now requires doublers and even triplers to hold it. I know of at least two in which the tailboom broke off in flight, and amazingly there were survivors in one.

[GeorgeMandes]

I have only been flying the 407 since November 2008, but I am not aware of issues with current ships. Are you referring to older or current production 407s? As I read the AD from 2003, it refers to:

This amendment adopts a new airworthiness directive (AD) for the specified Bell Helicopter Textron Canada (Bell) model helicopters that requires preflight checking and repetitively inspecting for a crack in certain tailbooms that have not been redesigned and replacing the tailboom if a crack is found; modifying and re-identifying certain tailbooms and installing an improved horizontal stabilizer assembly; and assigning a 5,000 hour time-in-service (TIS) life limit. This amendment is prompted by cracking discovered in other areas of certain tailbooms and introduction of a redesigned tailboom with a chemically milled skin, which does not require the current inspections.

Bell Helicopter Textron Canada Model 407 Helicopters (http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/29844B08B5EEF73E86256CE800597A2E?OpenDocument)

When was the last accident that resulted from the recurring tail boom issues you reference? It would also be helpful to know what were the dates of the two accidents you reference.

[Aesir]

Some time ago Bell announced they were going to discontinue manufacturing the 206B model.

Is that still a fact and when will the last be built?

[Ian Corrigible]

According to Elfan ap Rees (truly one of the best journos in the industry), the last JetRanger was S/N 4689, which went out the door at Mirabel in January.

I/C

[i2gofly]

I probably said this in the past but I'll say it again, in my opinion, this is a big mistake from Bell...

[EN48]

this is a big mistake from Bell...


There is a persistent rumor that Bell is reconsidering this decision, and may resume production using the RR500 series engine.

OTOH, this is a design that dates to the early to mid sixties. Perhaps it deserves to rest in peace. What Bell really needs is a 4-5 place light turbine with a modern (composite, hingeless) MR system, more tail rotor authority, no broom closet, etc. IOW, a scaled down 429 (219?) :ok:

[luisf4]

In Line And Word The Number Even Fits The Props... 219 Sounds Good!

Besides, God knows how much longer Bell will lose market for Astar's .... it's time to renew the series and come up with some new project!

They don't developed any news in the light single turbo axis long time I guess .... there is 1 429 around here in Brazil but you cant see many Rangers here.... most 109k /astar's and Ec120b

They are loads of this Lil Bird here but I still fail to see Rangers in numbers one or two perhaps some times.... wish I could fly a 206 one day

[i2gofly]

EN, I hope this is true... while they are at it, they should also keep the B430!:ok:

[206 jock]

On the other hand, us owners (well, me anyway) are hoping that the end of production will result in inflating prices for good used examples:D

However, practical experience of helicopter ownership would indicate that such aspirations will probably remain a pipedream:ugh:

[Bell_Flyer]

Bell had a stranglehold on the marketplace with their 206 series up to the 80's and maybe mid 90's - but they then sat on their hands and let the Astars, 109's and EC's overtake them in every category from speed, comfort, power and so on.

I have several suggestions for Bell's new CEO:

1. Sack any engineer that takes more than 30 years to fix a problem - eg the 2 year calendar life of TT straps. How many times have we heard Bell say they'll have one very soon with say, 10% more life or double the life or "on condition". This excuse is wearing thin.

2. Park an Astar or EC-130 in the middle of their Mirabel or Fortworth hangar and COPY (Yes COPY) then improve on these designs. Bell has proven for many many many years they can't build anything that looks like a 206 or a Huey (both great machines for their times - but very tired designs now).

3. Bell still uses corks as a seal - wtf? Even my local vineyard has moved away from corks...

4. The 206 is as agricultural as my John Deere. How about a 'corporate kit" that removes the screw heads from instrument panels, classier fasteners for hatches - hell my Massey Ferguson's got more aerodynamic hatch catches than the 206.

There are still many people who love Bells (me included) but we're a diminishing breed. I think the new CEO needs to lead from the front, take the competition seriously and not produce Bell Very Long Rangers V for their next single engine model.

[luisf4]

has a big point on that one ..... corks?????

[EN48]

Bell had a stranglehold on the marketplace with their 206 series up to the 80's and maybe mid 90's


IMHO, Bell has suffered the effects of profit harvesting which is all too common in the corporate world. Any CEO of a business unit in a large. multi business corporation knows that his assignment will last a few years, after which he will move up (bottom line at or above expectations) or out (bottom line below expectations). Investing for growth/market share is penalized. Bell handed EC market share dominance without a fight. Too bad, and wont be recovered, if at all, until long after the current CEO has moved on. :ugh:

[Vertical Freedom]

Good morning, anyone have performance graphs on the HOGE & HIGI for the C20J engine in the ole B206 please? Cheers ;)

[RVDT]

Don't read anything into the C20 "J".

It is only a "B" with a different pitch in the gearbox gears to try and reduce noise. There are no performance differences.

[Aubrey.]

How bizarre, meant to look like a Cobra? Wouldn't Iran be better selling their stock of 206s and put the money into a few decent and proven attack helicopters?

Out of interest, what sort of type approval would this machine have to go through in Iran?

[Aubrey.]

Damn me and my evil Western logic :ok:

Perhaps when they take over the world they don't want to have to rely on someone else's parts availability... ;)

[carsickpuppy]

EOR --

Did you get the pic by hiking through Iran on holiday? :oh:

[ecureilx]

maybe they up-armoured it so much that they only could lift a 8 round rocket launcher and a .22 gun .. :eek:

[Hell Man]

In combat I reckon I could take out about four of these 'Shahed’s' with a single unarmed 500D!

[krypton_john]

Too easy. Just fly circles around them until their TT straps fail.

[topendtorque]

Too easy. Just fly circles around them until their TT straps fail.


lol there,
did you know that is how the australian native aboriginals catch the bush turkeys. (known as bustards)

being rather stupid and curious birds, the natives simply walk around them whilst pretending to look at something else until the birds' neck breaks, then they grab em and roast em.
simple.
yep it could probably also work for that other stupd looking bird above.
cheers tet.

[Saint Jack]

Regarding the discussion of retiring/resurrecting/re-inventing the JetRanger, Posts 1123-1132, whatever happened the the JRX? This was proposed by BHT a few years ago as a (possible) replacement, or was it simply a ploy to test the market for such a helicopter. Anyone got any firm information?

[levo]

Hi all i am in the market for a jetranger around 200k must be bell not agusta and have c20b engine e me if you know of any yes i have checked most sites but there might be a few owners thinking of selling

thanks Levo.

[stix]

Should be a few more on the market once the r66 is in full swing

[206 jock]

Should be a few more on the market once the r66 is in full swing

D'ya think so? Personally I bought a JR as I just didn't want an R44, I can't imagine that many jetbox owners will be interested in the R66.

I would imagine that most 'incomers' to the R66 will come from R44's rather than 206's.

[toptobottom]

206 Jock - agreed. The R66 might be a cheap turbine, but IMO it's still a lot of money for a cramped and ugly 5 seater. Instead of $750k for a new R66 I'd much rather look at a good used EC120. Or if my budget was $350k, an R44 or jetbox.

[topendtorque]

If only Frank had hired a capable styling designer all those years ago I'm sure we could have had economy with just a smidgen of style. Alas it was not to be!


All should not be woe, after all there is a new Robinson starter on the blocks, seen here at pprune, a more reliable newshound than the Daily Tele at the corner shop.
It did look a bit chunky at it's last showing, but and alas the Marquis Battista is no longer with us I lament, however his successors seem more than up to the task to fulfil your suggestion as above.
tet

[topendtorque]

And is this new creature to which you refer by any chance the elusive "Reightyeight?"


Yes, and highly reighted down under.

[311kph]

A quick few questions:
- magnetic compass is positioned rather strangely on BIII's I fly, on the right side , knee height, just in front of right front door. Is this common place, and if it is, why? Why not in front, in the middle? Some bad interference?
- what's the story behind two TOT peaks during startup (C20B)? Why are there two, what influences on their values and time saparations?

Thanks

[vfr440]

311kph
It's a standby compass, (so you're not expected to use it as a primary reference for direction!) that's why its location.

Two peaks on TOT during start up are for the initial fuel introduction (to ensure thngs don't get too hot with the limited amount of air flowing through the turbine section.) :sad: And then an introduction of more fuel as an acceleration up to self-sustaing at 58% N1 and then on to your stabilised idle of 64+ or- 2% ( I think). Again so you don't have stagnation and a long hot soak whilst the airflow builds up. Lots of thermodynamic bad issues with that, manifest themselves further down the line.:E

As a by-product of all this Allison (sorry chaps, showing my age :ooh:) R-R recommend hot(er) and fast(er) starts:)

There you go, have a good one :ok:~ VFR

[Earl of Rochester]

311; You may find this of interest: http://www.pprune.org/rotorheads/432566-jet-ranger-preflight-start-up-shut-down-video.html

[RVDT]

Drivel alert!

It's a standby compass, (so you're not expected to use it as a primary reference for direction!) that's why its location.

Really? So where is the "main" compass?

Have a sniff around a JR and work out where the battery cables are! Then you might agree it's the best place to locate the compass.

2 peaks on start?

You could say the two peaks or one trough. It is to avoid surge/stall at a certain speed. Accommodated by the start notch valve in the FCU and subsequent adjustment to the Wf/Pc ratio.

[Gomer Pylot]

I think the compass location is a combination of maintaining distance from the battery and the taxi/landing lights, and space. There is no good place on the glareshield, and on the right is an empty space visible to the pilot.

The two peaks are there because that's the way the Allison engineers designed it. It would be more convenient for the pilot if the temp came up slowly to a point in the green and just stayed there, but no part of the 206 was designed for the convenience of the pilot. It is what it is, so accept it.

[FH1100 Pilot]

Accommodated by the start notch valve in the FCU and subsequent adjustment to the Wf/Pc ratio.

Well that surely explains it clearly! Uhh...I think...

Actually, I prefer Gomer Pylot's take: It is what it is.

[Gordy]

All you ever wanted to know about Allison starts but were too afraid to ask:

SEE HERE---you're welcome (http://fireheli.com/Files/allisonstart.pdf)

[handbag]

Gordy, I was told that an upgrade in the FCU bellows has invalidated that letter?

[nonolight]

..........

[47guy's]

G'day to All

Re'f BELL 206 performance computer and cruise data guide

I know a wizz weel computer exist for the OH-58A kiowa.

Wonder if we have a equivalent for the civil 206b,b2,b3,l,l1,l3,l4.

GUY

[Phoinix]

A pilot got en g chip light flying a Jetranger and landed on a field. The technician that was with him took out the chip and found a "hair like chip" on the detector. After second start-up there was some blue smoke from the exhaust.

Despite that and the fact the helicopter was 2 hours from major maintenance, a TRI decided to fly the helicopter back to base some 20 miles over hilly and wooded terrain.

My thoughts; I would let the helicopter come to base by truck.


What do you think? Anything similar happened and can be found in some "final report"?

[Chris P Bacon]

Hair like debris is normally pick up from one of the labyrinth seals. nothing unusual if the engine is just out of repair.
After the first chip light, I would always advise a 30 minute ground run taking the aircraft light on skids. If no further warning, you should be good to go.
Keep the debris and have it analysed. A good M250 facility will do this for you and let you know if it is bearing or gear material (even potentially which bearing or gear)

[Phoinix]

The engine is roughly 1000 hrs since overhauled.

I would say there was 5-10' ground run before the flight back.

[Helinut]

In general, the engine manufacturer has a specified maintenance procedure for action following an engine chip. In the absence of something else, follow that procedure. Not sure what RR specify for the Jetbox.

[Gordy]

I'm with Chris. Save the "sliver", hover the aircraft for 5 to 10 minutes before flying over "unsuitable" terrain, then fly it home.

No big deal.

[John Eacott]

As with Chris and Gordy, I would have no issue with the decision that was made. A qualified technician has checked the mag plug, a TRI has decided to fly home, the engine was run for ~10 minutes before departure and (I guess) no further chip warning occurred. Especially if the chip was 'hair like', there is no issue that I can see that would warrant the helicopter being returned on a truck.

Quite honestly, you are likely to get more damage from the pounding the engine would get on the back of a truck :=

[Phoinix]

Thank you for your input. The thing that bothered me was the blue smoke from the exhaust. Addition to "just being a chip".

[Chris P Bacon]

Have a look for any signs of oil puddles at the bottom of the exhaust collector (#5 seal leak), oil around the bleed valve (#1 seal leak), at the gearbox vent tube exit (internal seal leak) or oil from the burner drain valve (#1 seal or gas producer labyrinth seal). Thesea are the normal areas that would cause a puff of smoke at startup.
Is the smoke present at shutdown?

[Chopper Doc]

Hi Folks,

How do you perform a power check in a Bell 206B. I'm reading the flight manual but the procedure seems a little vague either that or I'm being incredibly dense this morning.

[Arm out the window]

It's been a fair while, mate, but the basic concept with turboshafts as I understand it is to climb to a height where you're not torque limited, but limited by N1 or TOT, pull to whichever of those limits comes first, note all the appropriate engine readings (Tq, N1, TOT, Nr), and the atmospheric conditions (temp, PA).
To get it more accurate, climb until you get near one of those limits and note the PA where it occurred. Then you can descend say a thousand feet below it, get nicely set up at the airspeed recommended in the manual and be ready to note the figures as you pass through the given altitude.
Another good idea is to do it above a nice big airfield or autorotational area of some kind (get a blanket clearance if in controlled airspace) so if it goes bang after maintenance, you can happily auto down and look like a hero when you put it back on the H.
Does that sound like any of the stuff in the manual? A bit generic, I know, but it should be something like that.

[heole]

Simple:

Establish a 52 Kias climb, Make sure anti-ice,bleed air, and Generator are Off, Pull collective slowly till TOT is above 738 deg C. Do not exceed any torque limit. When above 738, stop pulling on the collective, Note your OAT, Pressure altitude, TOT, Torque, Ng, and report the data on the power check chart. Do not forget to switch the Gen back on after power check. Refer to your flight manual Performance section. Clear explanations are there

[Gemini Twin]

Really not that complicated but do it in hover or cruise not climb, it's too hard to record everything accuratly while climbing.
N1 should be high enough to ensure bleed valve is closed say 96 -97% Record OAT, Pa, TOT and torque.
Enter chart at OAT, go up to TOT, across to Pa then down to torque.
If recorded torque is higher than chart torque you are good to go, if lower first clean compressor. If you are lucky it will come back up!

[Perra]

And how do you do it on the Longranger? Read the manual today and cannot get my head around it. Hmmm

[KiwiRotorWrench]

I need to know who makes/made the aftermarket Solid State Electrical panel mod to replace the carbon pile voltage regulator in the hat rack. Got a flyer when I was at factory school in '96, but my books are not where I am right now.

Anyone ever put one in? Work OK?

KC

[BartBandy]

CF-2011-44 (http://wwwapps3.tc.gc.ca/Saf-Sec-Sur/2/cawis-swimn/awd-display-cs2101-wnd.asp?rand=&vMode=0&showPdf=False&ovid=CF_CF-2011-44_0)

Bell Helicopter Textron Canada Models 206L, L-1, L-3 and L-4 helicopters equipped with a main rotor blade part number 206-015-001-107, -109, -111, -115, -117, -119 or -121.

[squib66]

The 2009 date on the ASB Rev A makes me think this followed the AirEvac EMS accident in 2008.

[Gomer Pylot]

That, plus another fatal accident on Nov 9 in Canada. Two blade failures, resulting in fatalities. Bell says it's a bad batch, and limited in the number of affected blades.

[mlagersson]

Would like to know what people think about the bell 206 isolation mount, is it just in the last few years that they are getting worse and worse, I mean i heard stories of people who heard of them breaking or failing once or twice in their career, now you looking at once every 1 or 2 years per machine...

What is the deal with this? Is there suppliers out there that are better than others?

[Shell Management]

There must have been an AD after the first accident?

[blackhand]

Lift is from the lift links not the isolation mount.
If you are destroying isolation mounts, look to how you are operating the machine.

[Gomer Pylot]

Yes, requiring a periodic alcohol wipe of the blade. I don't know if that was required in Canada, but I think it was. If so, it obviously wasn't sufficient. Some operators here are replacing blades with affected serial numbers, not trusting the alcohol wipe inspection after this incident.

[Chopperlover]

Hi ya'll,

Oil, grease leaks, harsh detergents and rain/sunlight will break down the rubber of the mount making it more susceptible to failing.

From my experience, they are not that bad... When coming from Lord, obviously.

Hope this helped.

Cheers! :ok:

[SASless]

No better truth was ever said!:ok:

no part of the 206 was designed for the convenience of the pilot.

The usage of the word "designed" is of and in itself an insult to anyone's intelligence!

[Saint Jack]

mlagersson: 'blackhand' was correct when he said look at the way you operate the machine, abrupt cyclic inputs will quickly degrade the isolation mount - it wasn't designed for military-style flying techniques.

Also, 'Chopperlover' was spot-on when he said "...Oil, grease leaks, harsh detergents and rain/sunlight will break down the rubber of the mount making it more susceptible to failing." keep the transmission deck clean and rectify any oil/grease leak from the input quill and/or forward diveshaft coupling as quickly as possible.

DO NOT attempt to replenish the main transmission oil by pouring directly from the can with the cowling in place.

[as350nut]

I am looking at buying a 206A (low skid) normal cat, with a C18, other than the obvious fact that these are lower powered than the 20b how do they preform with 4 people and full fuel in Australian conditions? If I replace the engine with a 20b do I need to replace tail rotor or anything else? Do I have to replace the whole eng or just the compressor to get more hp. Thanks in advance

[Saint Jack]

as350nut: First of all, there's no such thing as 'low skids', this is a common misconception since they're always compared to 'high skids'. The correct term is 'standard skid gear'.

"...4 people and full fuel in Australian conditions..." might not be achievable under some (most?) conditions. Plus, have you determined if the 250-C18 is still supported in your area?

If you eventually decided to replace the -C18 with a -C20 the work will (should) be performed in accordance with a Bell SI (Service Instruction) but before commiting yourself ensure that a parts kit is available from BHT - this is a VERY old conversion. If I remember correctly, the principal parts requirement is, in addition to a -C20 engine, a) a new torque indicator, b) a replacement collective contiol tube (on the transmission deck) and, c) new engine mounts.

I'm not sure how the -C18 is, or can be, converted to a -C20 in the field.

Finally, if you do manage to get the conversion done don't forget to amend the Flight Manual, and remember, you don't now have a 206B (another misconception), what you have is a 206A flown in accordance with a 206B Flight Manual.

[SuperF]

Performance would depend on the size of the people.... The smaller variety would be fine, but after a few years and a few tinnies, might get tough in the summer...

You shouldn't need to change the tail rotor, just keep it into wind, and moving if loaded.

You may need to upgrade transmission from 3 to 4 stage. 206A to B xmsn, I think... Most people on here will tell you that there are no 3 stage xmsns around anymore, but there are still a few, very few.

"A" model with C20B is a great machine, and with the 4stage xmsn will out perform the latest 206. It's the lightest airframe, with good eng, and xmsn, has to be a winner. If it's really early A model it was made by Beech, pre 600, I think and they are even lighter.

In NZ we call the conversion the 206 A/B, not sure if that's an official title, or just our way of keeping track of things, back when there were lots of A's here.

[rick1128]

I looked at an A model a couple of years ago. For the most part, C18 aren't supported very well, if at all here in the states so you can plan on having even less support else where. When you do the C20 mod, you will have to disconnect the tail rotor boost. The A was the only one to have it.

About the only advantage of the C18 is that it has no cycle items in the engine, unlike the later versions, which is why the ride folks like the engine.

[krypton_john]

Drinks less gas though. A c-18 ship would be great for a private owner who wants to jolly around in a turbine for the least cost. Just don't carry more than 2 fat-ass pax.

[206 jock]

When you do the C20 mod, you will have to disconnect the tail rotor boost. The A was the only one to have it.

Not on my old Agusta Bell 206 A/B. Had boosted pedals.

[23 Inches]

Greetings

Can anyone shed some light on the cost and availability of spare parts for the 206 given that production of this machine ceased in 2010..? Is the Bell 206 still a viable option, given the history of the Bell 47..?

[krypton_john]

Given that the 47 is still a viable proposition 50 years on I'd say so!

[Darren999]

I have a 206 with floats, I want to take them off and replace them with high skids, and then sell the float skids..
Anyone know of any skids for sale?
Anyone need a set of floats?
If so, please drop me a PM.
Thanks..
Fly safe..

[23 Inches]

Greetings

So no one is particularly worried about cost of spares in the future...? Can anyone tell me what will happen when main rotor blades time out and need replacing..? Is there an after market solution for this..?

[helonorth]

If you're looking for skids or want to sell the floats, try Airplanes & Aircraft Parts For Sale - Free Classified Ads - Ultralights to Airliners - Used Aircraft and Helicopter Sales and Classifieds including Cessna, Beechcraft, Piper, de Havilland, Boeing, Airbus and Lockheed planes (http://www.barnstormers.com)

[Gomer Pylot]

23, I would bet the rent money that spare parts will continue to be available for decades, at least. I won't guarantee prices, however.

[robert calvert]

bell 206 after market tail rotor blades and TT straps has anyone used them and can they comment on the quality

[206 jock]

Just having some Airwolf straps fitted to my 206, will be released to service next week.

I'm looking forward to a smoother flight, a 3 year change cycle (as and when approved) and world peace. All with a cheaper strap! Hurrah!

Let's be honest: Bell have been milking the strap situation for way too long already. There was no incentive for them to change anything. About time somebody did something about it.

[Aucky]

I've been flying an IFR equipped 206L-1 with the SFENA autopilot/ministab/FCS kit for the past few days. Looking for a little system knowledge...

Could anyone explain the individual roles of the 3 main stabilisation parts: Ministab, Force Trim (and auto trim), and Autopilot, and the relationship of how they interlink?

One thing that is very noticeable is that if the auto pilot is engaged but the force-trim is not indicated as central in pitch and roll (2 axis autopilot) then the autopilot often doesn't capture the intended heading or attitude, and one must depress the force trim release, centre the indications, and then try again. I'm trying to get my head around the role of each unit individually and how they interconnect, to avoid mishaps when engaging the autopilot (which seems to happen most following a manual instrument approach, having utilised the force trim release quite a lot, and when going around in cloud with enough to be doing without incorrect headings and attitudes). Is it simply the case that you must check the force trim is centred manually (with the release button and cyclic inputs) each time before engaging the autopilot?

Thanks

[helofixer]

We use the Van Horn tail rotor blades on almost all our ships and love them. 5000 hour life limit vs 2500 for the bell blades for a few thousand dollars more. Only issue we have found was one blade had a feathering bearing worn past limits at around 2500 hours TIS. Great support from van horn they sold us the bearing and loaned us the tooling to change the bearing and in about an hour we were back in the air making money.

[mldavis99]

Home of Chaparral Systems (http://www.chaparralwest.com)

Please take a look at the picture on my home page at the link above.

I flew OH-58A,C & D during my career in the Army and have recently come across this silver filigree presentation model of what appears to be a 206B that may have been made (the model) in Turkey.

I have no clue to its original but wondered if any of you might have ever seen it or may know anything about it?

Thanks,

mike

[ReefPilot]

Just a quick question regarding use of starter on shutdown of 206. I know in the emergency procedure section of the flight manual it states that in the event of an engine hot start/shutdown the throttle should be closed, fuel valve off and crank the starter until TOT stabilizes at a normal temp. Now my question is what are the implications for the engine, if any, if you do use the starter, if needed or inadvertently, on shutdown? As in you close the throttle but you notice the TOT rises again so you shut off fuel valve and crank starter. Does the cranking of the starter do any damage to the engine itself when used in this capacity? Thanks.

RP

[LRP]

the answer to your question, in a word, is no. Using the starter to continue the airflow through the engine does not damage the engine. I suppose if it was necessary to keep it going for an unusual amount of time you might overheat the starter/generator but that would be a bit of a stretch.

[Ascend Charlie]

After shutdown, the TOT goes down to about 300 degrees, but once the N1 reaches zero, the temperature goes up again - there is no cooling airflow, so the hot metal heats up the air in the turbine area. It will slowly rise above 400 again.

This is normal.

It is only if there is a rise above about 450 or the rise is very rapid that you would do a cooling run. Remember to pull the igniter C/B to save some strain on the battery, and it also stops ignition of any residual fuel in the can.

[paco]

I seem to remember there being an instruction from Allison at one point forbidding the use of the starter on shutdown as people were doing it on a regular basis and cracking turbine blades. It was many moons ago, but occasional inadvertent uses should not do any harm.

Phil

[Chris P Bacon]

See the following statement from Rolls Royce CSL 1178

"It has come to Rolls-Royce’s recent attention that a number of Model 250 operators have adopted another engine manufacturer’s cool down procedure intended to reduce coke/carbon formation in the turbine area.

We understand that this procedure calls for the hot engine to be motored with the starter immediately following shut down to provide additional oil flow for cooling the turbine bearing/shafting area.

Operators must understand that this procedure is not recommended by Rolls-Royce and can accelerate rim cracks of the first and second stage turbine wheels due to the thermal shock of introducing a flow of cool air over the turbine wheels."

[paco]

I knew it was there somewhere :)

So it was being done after shutdown. Thanks for that.

Phil

[ReefPilot]

Thanks for the replies.

RP

[toptobottom]

...introducing a flow of cool air over the turbine wheels
Isn't how the engine works?! If the starter is cranked before the post shut-down heat has built up in the turbine wheels, I don't understand the argument? :confused:

[ajwasco]

Looking for some input on xmsn oil psi on a 206. Xmsn oil psi on ground at 100% was 45 psi. In flight it rose to 50 psi and after one hour began to steadily drop to low 30's. Not enough to illuminate caution light. Replaced psi regulator, bled line to indicator set to 45 psi at 100% flew for 1 hour and stayed rock steady at 45 psi. During delivery today one hour into flight began to steadily decrease. Pilot returned to station and on final dropped to 30 with indication. As hovered to park rose to 40's. Regulator replaced, lines blown out and checked for obstructions, filter removed and inspected. Are we missing something?? Thanks

Following day, replaced pump, same results. Pulled both jets inspected replaced packings, run up, same results. Hung new indicator with same results. All on ground runs starts at 45 and steadily drops to just above 30

[RVDT]

ajwasco,

What is the oil temp doing?

Too much oil will make the MGB run hot and foamy.

Check the correct level. It is not a bubble at the top of the sightglass.

Full is halfway up.

Oil can migrate from the engine over time if freewheel seals are U/S.

[ajwasco]

Oil temp is normal, after about 15-20 min temp is @ 80 and PSI is dropping to about 32 PSI. It's in the green however my concern is why it's dropping from 45-48 to 32 in such a short time. Caution light will illum below 30. Oil level is good and checked again after run during run up oil level center of sight glass, no foaming, no loss of xmsn fluid or increase in engine oil. Not xferring oil. Bout to T in a psi guage to line coming of xmsn and run again to verify what psi is on GB. Thanks for the reply.

[311kph]

Hello everybody!

Looking for information regarding starting procedure of 206BIII/250C20B/BENDIX.

There was a problem during starting of one particular machine.
Starter was engaged, throtle was cranked at 13% to just past the idle stop, starter released on 58% N1. When it reached 60% N1, it flamed out. To roll off the throttle, it was needed to push the idle stop release button.

Now comes the confusing part (besides why it flamed out).

There are two idle stops. Two clicks, close to one another.

After discussing with different pilots, they all have different starting techniques.
Some say they are gradually feeding the throttle during acceleration, watching TOT and end up just past first click,
some are cranking it open just past the first and are holding it next to it,
some are doing this also but after it peaks they roll it just past the second stop,
and some are cranking it just past the second idle stop and are holding it next to it.

The questions:
Which is the proper procedure? RFM addresses only idle stop (not first, not second).
Are there exact self-sustaining N1 rpm's for this engine?
Does these rpm's depend or have enything to do with position of the throttle during acceleration to idle (if it's left next to the first idle stop from closed side, or between the first and second idle stop, or just past the second idle stop).
Does the flame out described above has anything to do with throttle position during start? (or should the battery condition, ignition exciter, etc... be looked )

I know it's a scarce info, but any thoughts?

Thanks

:):*

[Hughes500]

Long time since I owned a 206 but there sounds like you didn't open the throttle for the idle stop to engage. See it on 500's when throttle isn't opened enough for idle stop to engage. Engine will accelerate past 58% then flames out as there isn't enough fuel . Would suggest either an issue with your idle stop or your starting sequence. I always open throttle until you feel idle stop engage then wind back to it that way you know you have opened it far enough

[Gomer Pylot]

I've never heard of two idle stops, and find it difficult to imagine how that would be possible. It might feel like there is another stop below the actual stop, but that's just a feel, and there is no stop. You can roll the throttle to just below the idle stop and feel a slight click, but when you're actually past the stop, the idle release button will pop up.

With a Bendix, the procedure is to open the throttle to the idle stop, just a bit more, and wait, while holding the idle stop button down so the throttle can be closed if necessary. If you roll the throttle back against the stop before pressing the detent, you run the risk of not being able to close the throttle even with the detent pressed. You do not want to try to start a BIII while modulating the throttle. If you can do that, then the fuel rigging is wrong, and that may be why the engine flamed out.

[Saint Jack]

Hi 311kph. From an old 206 hand, here are my answers to your queries:

1. Which is the proper procedure? RFM addresses only idle stop (not first, not second). The 2-click idle stop has been a characteristic of the 206 Series from Day 1. The second 'click' (going from shut-off to idle) is the one referenced in the RFM.

2. Are there exact self-sustaining N1 rpm's for this engine? Probably. It must be remembered that 'idle' is more accurately termed 'flight-idle' and is a higher setting than 'ground-idle' to ensure that the rotor blades rotate at a speed that ensures the pilot retains aerodynamic control of them otherwise wind gusts etc. while sitting on the ground may result in a blade strike (on tailboom), mast bumping or spike knock. Perhaps someone with knowledge of the turboprop installation can add to this.

3. Does these rpm's depend or have enything to do with position of the throttle during acceleration to idle (if it's left next to the first idle stop from closed side, or between the first and second idle stop, or just past the second idle stop).No, the engine RPM acceleration after light-off is a function of, first, the start-derich system and then the acceleration control setting on the FCU (note that different P/N's of FCU have different adjustment controls to fine-tune the start). Of course, a good battery/GPU will give better starts. Remember that this engine requires a hot and fast start - not a slow and cool one, there is an DDA/Allison/RR document on this topic but sorry, I can't remember the details.

4. Does the flame out described above has anything to do with throttle position during start? (or should the battery condition, ignition exciter, etc... be looked ) Most probably, with the twist-grip at the 'idle' position (second 'click' going from shut-off to idle) check the pointer on the FCU. It should be at or slightly below the 30 degree mark, if it requires adjustment it is vital to ensure afterwards that the lever firmly contacts shut-off stop and max-power stop - failure to ensure this will lead to other problems. You said the engine flamed out when it reached 60% N1, this rules out the battery condition and the exciter as source of the problem.

Hope this helps.

[Vertical Freedom]

2 click throttle in a JetBox :confused: flown 30 different jetties over 24 years & none had 2 clicks, none :eek:

[Saint Jack]

Vertical Freedom: I've been involved with 'jetties' (A, B and L) for over 40 years and all of them had two clicks, all of them. The next time you sit in your 'JetBox', close the doors and ensure the cockpit is quiet. Put the twist-grip to 'shut-off' and then slowly roll it towards 'idle' - this must be done slowly - and as the twist-grip gets to the detent position listen for a soft 'click', at the same time look at the idle release button and you'll see slight movement (usually from side-to-side) - this is the first of two 'clicks'. Keep rolling and almost immediately you'll hear another louder 'click' and see the button pop out - this is the second 'click' and is the correct 'idle' position of the twist-grip. I'm surprised you haven't heard about this previously as the 'two-click' topic has been discussed over and over again in the past, I believe it was also featured in an earlier edition Rotorbreeze.

[311kph]

Thanks guys, much appreciated!

@Saint Jack Great info, great help

Just been trough every machine here, everyone has two idle stops. In quiet hangar you can hear (and feel) them both snap.

So, we'll use second one as the one referenced in the RFM, no gradual feed, no first click,...

@Hughes500 Thanks. Could be that he didn't open the throttle enough for the idle stop to engage. He said that after the flame out he pushed the button and rolled it off, but couldn't said with certainty that it was actually locked and needed pushing release button.
With all the noise and vibrations going one, you can't rely much on hearing. You can feel clicks on your finger, but I guess the only thing certain is to just pass stops, roll it back and ensure it won't go back to cut-off.

Thank you guys

:):*

[Hughes500]

311 kph is the pilot new to the Allison, if he is he is not being positive enough with the throttle as he doesn't want the infamous hot start !!!

[311kph]

Relatively new, yes. There is also a story here about a guy who's been flying mostly 212. One day he sat in JetDanger, starter, 15%, whacking the throttle all the way (full open), then back to idle stop, watch TOT - game over.
So yes, being a relatively new with Allison along with hearing the above story, it could be that he was a bit shy with throttle.
Anyways, easy fix, no harm done.

:):*

[FH1100 Pilot]

So many misconceptions, so little time...

1) The Bell 206 has ONE idle stop. Not two. There *may* be two *clicks* heard as you oh-so-slowly increase the twist-grip up from cutoff. The first *click* may have something to do with slop in the design of the plunger/lock/release mechanism on the 206 twist-grip. The first *click* means nothing. You rotate the "throttle" positively to the IDLE-DETENT. *That* is the proper position for introducing fuel in a C-20 equipped with a Bendix fuel control.

2) With a Bendix fuel control, at light-off (15%) you get EXACTLY the same amount of fuel at the idle-detent as you do at "full-throttle." Hear me now: You CANNOT get "extra" fuel from a Bendix if you go above idle during the start (like, below 40-45% N1 or so). What you get at the detent is ALL you're going to get.

I like to mess with other 206B pilots, especially those who don't know the 206 very well, and especially in a particular ship that I do know well. While demonstrating a start, I'll get to 15% N1 and then rotate the throttle to FULL. Sometimes I'll even "pump" the throttle like I'm priming a Bell 47. The ship starts absolutely normally. It freaks people out. All the way out. People do not believe this. Supposedly knowledgeable people will tell you different - that the more you go past the idle-stop the more fuel you'll get. WRONG! Doesn't work that way. Isn't designed that way. (It should not be necessary to point out - although somebody surely will - that you cannot do this in an 206L-1, L-3 or L-4.)

311kph, I do not know why your 212 pilot torched the 206B if he did what you described. That should not have been a problem. Perhaps there was some other issue with the engine (or maybe it was an L-model and not a B-model?). I'm always very cautious when starting a ship I'm unfamiliar with.

So. Do not be afraid to go right to the idle-detent stop (or slightly above, as Gomer Pylot suggests) when starting a 206B. If the "throttle" is open far enough to get fuel into the burner can, that's all the fuel you're going to get. Period.

3) The RR 250-series engine is fairly self-sustaining at about 45%. We keep the button down to 58% (and set the idle just above that) to keep the main rotor turning, as has already been suggested. You can release the starter button "early" (like below 58% and the engine will run just fine - as long as the throttle is above the detent and the TOT is under control).

4) Another misconception with the RR-250 is about opening the "throttle" with the engine shut down but the fuel valve on and the electric fuel boost pumps operating. OPENING THE THROTTLE DOES NOTHING. It does *not* allow fuel to be pumped into the burner can. This has to do with the design of the engine-driven fuel pump...which is what we call a "positive-displacement" pump. If it is not turning, then the boost pumps CANNOT push fuel past it. All the boost pumps do is supply fuel under pressure to the engine-driven pump. If the engine-driven fuel pump quits on you in flight, your engine WILL quit, whether your boost pumps are on or not. Thankfully, the engine-driven fuel pump is a pretty reliable device.

So before you hit the starter button, ALWAYS ALWAYS ALWAYS do one final throttle check: Idle-to-full-back-to-detent-then-cutoff. Then you KNOW thy throttle is fully closed.

Having said that, I once heard that if the engine-driven fuel pump is turning as little as 2% it can supply "normal" pressure to the fuel control. Just keep that in mind, for it may be true.

I've had various fuel control problems over the years, mostly associated with rigging. So preflight the linkage well. With the engine cowling open, manipulate the fuel control linkage to fully open and check the pointer. Then pull it back down to idle and check the pointer again. DO NOT FORGET TO CLOSE THE THROTTLE in the cockpit before you initiate the start sequence or you'll be in for a nasty surprise.

To recap: If you're getting two *clicks* as you open the "throttle" while starting a Bell 206B then you're doing it wrong. Go right to the idle-cutoff detent. Make sure the button pops all the way out. Once you release the starter button at 58% and the N1 rpm is up, then increase the throttle slightly and come back down to the idle-stop for your one-minute warmup. If the engine flames out you know you didn't go far enough. Practice makes perfect.

4) The 206B-III checklist calls for a "decel-check" at the end of the day. If I'm going to be doing training in a 206B, I like to do a decel-check before take-off, so that I know it's not going to flame out if we roll the thing to idle in flight to practice an auto or something.

[vfr440]

Engineering here (!) - confirm point (4), the fuel nozzle has a spring loaded metering valve within it. Fuel will not flow to the primary nozzle until pressure exceeds 30psi (and to the secondary nozzle as well at pressures over 150psi). Boost pump pressure is nominally what, 4-10psi? Either way, not enough to open the primary nozzle flow.


Simples http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/icon25.gif - VFR

[311kph]

@FH1100 Pilot : Thank you for extensive reply. The 212 pilot that torched the 206, long time ago, some say it was B, some say it was L, so no luck there...

Here:

Uno o due - YouTube

I don't suppose it makes any difference this being Agusta-Bell? Guess not.

Well then,

'' Dear Mr. Bell...''

:):*

[Vertical Freedom]

There is no mention of any 2 clicks in the RFM - that's the beginning & end of the story :8 don't presume slop in the linkage system equates to 2 clicks :{ if all else fails refer the RFM it is Your Bible or Bhagavat Gita :)

[311kph]

slop in the linkage systemWell, maybe to you, but they look like two fully grown, responsible adult clicks to me. The rest of the ships have them too. Stop the throttle both ways, too...

Yes, the RFM mentions only one click, I was having trouble identifying which one of theese two is THE ONE.
Saint Jack said that second 'click' is the one referenced in the RFM.
Problem solved.


:):*

[Saint Jack]

Let's try to put all of this information regarding 2-clicks into perspective now that we've received so many wide-ranging replies.

1. 'FH1100 Pilot' in his Post #1217 says there is only one click. This is essentially correct but the design of the twist grip and detent button mechanism results in 2-clicks when rolled slowly to detent, this is NOT the result of 'sloppy linkage' nor is there any difference on an Agusta-Bell machine. This is the way the helicopter was designed, built and certified.

2. The 2-click confusion arises when pilots new to the 206 roll the throttle slowly towards detent (light-off) being wary of the scenario 'Hughes500' in his Post #1215 aptly describes ".....he doesn't want the infamous hot start !!!" (and the associated cost).

3. So what happens when a new pilot becomes confused and a definitive explanation is not readily available? Responsible persons like '311kph' in his Post #1208 ask around to find an answer (incidentally, 'Hughes500' in his Post #1215 hits the nail on the head with his statement "...'he is not being positive enough with the throttle....").

4. 'FH1100 Pilot' (for whom I have a lot of respect after reading some his previous postings on other topics) in his Post #1217 states "....I like to mess with other 206B pilots, especially those who don't know the 206 very well....". This of course, represents the other end of the spectrum i.e. "I know it, so why don't you know it". Messing with a pilot who doesn't know the 206 very well and may be doing his first start/s on a Model 250 engine can have significant financial and professional repercussions.

5. Then we have 'Vertical Freedom' in his Posts #1212 and #1220 who appears to have his head in the sand (or snow or ice or whatever they have in Nepal) "....There is no mention of any 2 clicks in the RFM - that's the beginning & end of the story..." oh really! No signs here of any willingness to learn.

6. So where are we, there ARE two clicks if you roll the twist-grip slowly BUT, rolling this slowly is NOT the correct technique for a start. Rather, the twist-grip should be rolled positively to the 'idle' position and, for new pilots to this engine, keep a close eye on the rapidly increasing TOT indicator (remember, there are two temperature 'peaks' during the start).

[Ascend Charlie]

After 7000+ hrs on a 206, mostly Bendix but some Chandler-Evans CECO, I have never seen 2 clicks. Probably because I have never been a pussycat with rolling the throttle on.

Start: N1 accelerating through 13% and likely to pass 15%, snap to past idle so button pops up, gently roll back against the stop. Be aware that holding against the stop will make it difficult to shut it off in a hot start situation. You can in fact have the throttle fully OPEN at this stage without anything untoward happening.

This is because the N1 FCU has only 3 tasks:
1. start the engine, and bring it to idle
2. Control the fuel acceleration schedule when the throttle is advanced/ retarded
3. limit N1 to 105%.

So, once you crack it to idle, it doesn't care where the throttle setting is until it reaches 58%, and then it looks around and says "Where is the throttle?"
If it sees it still fully open, then it will pour fuel in to make it accelerate and burn its @ss off. If it is at idle, it calmly sits at 62% or thereabouts, and waits for the throttle to move.

Once at idle: let it sit for a minute to calm down, then up to some setting past 70% to allow the Gen to be turned on without dragging the N1 back down below self-sustaining RPM.

Roll on the throttle gently, and the FCU controls the schedule nicely - the TOT will jump each time you open the throttle, let the N1 accelerate, then drop back to its normal setting.

On shutdown, make sure you close the throttle fully - I once had a sticky throttle cable, and after doing what I thought was a normal shutdown, I unstrapped, took off my helmet, and wondered why the blades weren't almost stopped, and what that strange noise was - the engine was still trundling along at 18% N1. Surprised the heck out of me.

[Vertical Freedom]

Saint Jack......who are You to tell me, or anyone of unwillingness to learn? that is the height of obnoxious arrogance :eek: After 24years in this game I'm still learning!!! ;) (every day up here working these extreme altitudes) :rolleyes:

Following your statement I went out & double checked the throttle on our B206BIII - 9N-AII & there is NO 2 clicks......did You hear? No 2 clicks :ooh: it's likely some slop in the linkages but it was never designed with 2 clicks :=

So please before You miss-lead or miss guide lower timers; follow the Rotorcraft Flight Manual procedures :ok:

Thank You & Happy Landings always :D

VF :E

[FH1100 Pilot]

Saint Jack, point taken on the "I know it so why don't you?" attitude. But I *try* not to demonstrate the starting technique in a demeaning or condescending way - I just try to show 206B pilots what happens during the start sequence. And I do stress that you *cannot* try such shenanagins in anything but an aircraft equipped with the 250-C20 engine. But again, point taken.

During the start, some 206 pilots...especially low-time instructor pilots...open the 206 throttle with extreme caution. It's like they're scared of it. They just squeak it open very timidly to lightoff, sooooo sloooooowly as if going past lightoff might cause it to overtemp. Perhaps they believe that they can "modulate" the throttle (and therefore the TOT) or perhaps they believe that it's possible to "give it too much fuel" if you open too far. Both are incorrect.

About the clicks. I've been flying 206's since 1982. And you know what, I've never noticed two *clicks*. That's probably because some B-models I've flown didn't do that. Plus, they're irrelevant. What really matters in the start is that you open the throttle to lightoff and make sure it doesn't a) flame out, or b) overtemp. The *clicks* or the button have nothing to do with that. Fuel control linkage position (i.e. "throttle") is all that matters. Experienced 206 pilots know this.

Some pilots hold the both the starter button *and* the idle-release down during the start so they can roll it off easily if needed. Which is fine...as long as...you don't inadvertently let the throttle slip back a bit and flame out...and as long as...you remember to get the throttle *above* the detent at some point. Pilots who hold the idle-release button down during the start will NEVER hear any *clicks*.

We might note (and remember) that a few different aircraft use the C-20B engine. The idle-release mechanism in the H-500 and FH1100 are very different from the setup Bell uses. (I have no idea what they use in the Enstrom 480 or Soloy 47.)

A word about TOT peaks. Yes, there typically are two. But! I've seen some fuel controls that are set up with very high lightoff temps and rather cool derich (or acceleration) temps. This causes a start where there are no definable "peaks" in the TOT, just one "spike" toward the redline and a gradual decrease of TOT as the N1 comes up. Point being: They all start a little differently; each 250-series has its own "personality" if you will. Different does not mean better or worse. DO NOT write it up if you don't see two distinct TOT peaks. DO write it up if the TOT has a tendency to frequently go over the redline into the transient on most starts, both hot and cold.

People hyperventilate over starting a turbine. Yes, the financial risk is high if you screw up, but the procedure is neither difficult nor complicated. Best thing to do is RELAX. Here's what I do - here is your pre-start and start checklist - all you need to get a 206B running:

1) MAKE SURE the battery is on, the blade tiedown is off, the throttle is closed, the fuel valve is on. MAKE DOUBLY-SURE. Triply sure. The position of *any* other switch or circuit breaker does not matter at this point. "Battery, tiedown, throttle, fuel valve" is all you need. All that other stuff was put there by the lawyers and the FAA. Hydraulics off? Who cares. Generator on? Big deal. Worry about all that other crap *after* you get it going. This ain't the space shuttle.

2) Hit the starter button. There are three things you're going to look for in quick succession. As the N1 comes alive, WATCH THE TOT that it's not increasing. If it's not, good! Now check for the oil pressure to start coming up, and check that the main rotor blade is turning. This is why I leave the blade right out front. You'll see it start to turn before you introduce fuel and won't have to worry about it at the 25% N1 point (which, if it's *not* turning then you have to abort the start because you probably left the blade tiedown on LIKE I TOLD YOU TO CHECK). And why would you want to take your eyes off the TOT during a critical point in the start?! Get this checklist item out of the way early, BEFORE you light it off.

Okay, recap: Hit the starter button with your eye on the TOT, quick glance at the oil pressure gauge and then another quick glance up at the rotor blade. Easy-peasy. Now, back to the N1.

3) Okay, if the N1 is accelerating smartly, start opening the throttle around 13% so we get a lightoff at 15%. If you're already at 15% NO BIG DEAL. Light it off. Go right to the detent as previously described. Once it lights off, KEEP HOLDING THE STARTER BUTTON DOWN. You'd be surprised at how many piston pilots release the button at lightoff. Oops!

4) Once it lights off, simply monitor the TOT and be prepared to cut it off if it exceeds the redline for more than ten seconds or if it looks like it'll go past the dot or triangle. If it does go over the redline, start counting "one-thousand one, one-thousand two..."

5) If the engine is accelerating nicely, you can release the starter button at any time above 50%. I've seen some pilots who are fanatical and neurotic about holding that damn button down until 58% EXACTLY! It. Doesn't. Matter. Or, hold the button down longer if you want to! If the engine *isn't* accelerating nicely at this point, there's probably something wrong. Either it's very, very cold out or you probably should've used an APU or battery cart.

6) Once you've released the starter, goose the N1 up a bit so you're sure you're above the idle-release, and then come back down to idle and verify the N1 is 60-62%. Congratulations, you're done.

Back in the bad old days of 206A with 250 C-18 engines, if you turned the generator on right after the start, the load of the generator could drag the weak-a** compressor down below 58%, triggering the Engine-Out warning system. So Allison and Bell wisely insisted that you don't turn the generator on below 70% N1. This "problem" has been solved with the mighty C-20 series. Turning the generator on at 58% (usually) has no discernable effect on the N1. Trouble is, Bell never modified the start checklist, which still calls for you to sit at idle for one minute (if the engine is cold) before going to 70% to turn the generator on. Hey, better safe than sorry, I suppose.

Me? Once it's in a stable idle at 62%, I turn the generator on. Yes, yes, I watch the N1 and the loadmeter. If nothing bad happens, then I turn on all my other electrical consumers while I'm waiting for the one-minute warmup (and I do my anti-ice and idle hydraulic check too). This way, when the one-minute is up I'm ready to roll to 100%, do a quick hydraulic check and go. You can spend ten minutes getting a 206B ready for takeoff. You don't have to. (Again, it's not a 747.) There are a lot of things you can do while you're sitting there twiddling your thumbs for that minute.

Remember, the checklist is not a "do-list." Just get all of the items accomplished before you takeoff; it really doesn't matter in what order you do them, as long as they're done.

Starting a turbine might seem complicated, or "tricky" to the uninitiated. But it's a piece of cake, really. I didn't realize how good I had it until I started flying these old helicopters with a radial piston engine. You actually do need three hands to start a Sikorsky S-55. I'm going to suggest that we put the starter button on the floor...like where some modern ships have the remote copilot intercom button (or where the high-beam button used to be on old cars for you guys out there who are as old as me).

[RVDT]

Anti-Ice and any optional bleeds closed always helps!

[Ready2Fly]

@FH1100
Great input and a good refresher for those who do not fly a 206 every day. :ok:

[Saint Jack]

I was hoping to post this yesterday but Mrs. Saint Jack insisted that I take her shopping for the up-coming Chinese New Year festivities.

'FH1100'. I fully agree with 'Ready2Fly (http://www.pprune.org/members/65398-ready2fly)' - a great input and a good refresher for those who do not fly a 206 every day. I'm also happy to see that we're essentially on the same page. We're good.

'Vertical Freedom (http://www.pprune.org/members/286435-vertical-freedom)'. The information given in the RFM is sufficient to ensure safe operation of the helicopter - we all know this. In addition to knowing the contents of the RFM, pilots learn a vast amount of detail regarding the background of individual requirements - the 'how', 'why' and 'where for' - of their helicopter during the conversion training, from a training captains, from refresher training and from interacting with other pilots etc.

However there's always room for improvement and from time-to-time the information in the RFM will be complemented by additional detail as it becomes necessary - but not always in the form of an RFM revision. Often, such complementary information may appear as an Operational Safety Notice (http://bellcustomer.com/bulletins.cfm), an Information Letter (http://bellcustomer.com/bulletins.cfm) or even an article in Rotorbreeze (although such an article generally seeks to add depth and clarity to a topic rather than announce specific requirement/s).

Nor does this complementary information solely originate from Bell, DDA/Allison/RR also publish information that goes to the heart of safe flight operations, for example Commercial Service Letter (CSL) No. 1176, 'Optimized Start Technique for Allison 250-C20 Series and C20R Series Engines' ought to be a must-read document for everyone associated with 206 Series helicopters. There's a lot of highly relevant information here that is not in the RFM.

Strict adherence to the RFM is quite right and proper - but not to the exclusion of supplementary information, wherever it may come from, that is aimed solely at broadening the knowledge of the pilot in order to ensure safer operation of the helicopter.

I'm now drawing a line under this topic, fly safe.

[helicopterray]

On the maintenance side here. I've rebuilt many collective sticks/ throttle assemblies. There is only one stop on that throttle. It's a 'step' that holds the pin down and releases when you rotate.

As far as why the engine flamed out, beyond the rigging check, I noticed there were dual controls installed in the aircraft. Check that the dual collective is engaged correctly into the base slot.
The throttle is connected through the dual collective stick as well, and if the slot doesn't engaged perfectly, it will cause flame out.

[Vertical Freedom]

Well there Yer go - ONE click.....Yes we must learn the quirks & uniqueness's of each & every machine machine we operate as Saint Jack rightly stated :ooh: :hmm: ;)

[Bellrider]

I have more than 4000 h 206 and i think i know what´s the meaning off 2 clicks.
If you turn the throttle very smoothly the spring comes for half a millimeter first, after that, the spring jumps in the whole engaged position......
But this fact has no influence in the fuel flow. i always say, the 206 has a digital fadac...there is only 1 or 0 :oh:

[Bell_Flyer]

On an L3, if I pull the collective aggressively at takeoff (1 POB or at MAUW) the TQ gauge flicks + and minus 5% as if the power is coming on then off. If I lower the collective to 30% or less for a few seconds then resume the flight, all's OK. Is this the FCU 'lagging' or a fault with the governor? If I take off "gently" then all vital signs are good.

The workshop has been unable to reproduce the problem. I can. Occasionally. Apologies if this question has been discussed before - I couldn't find it.

[SuperF]

Don't pull it aggressively, you won't have the fluctuation...

[vfr440]

You don't mention any N2/Nr droop? I'd be surprised if it was the FCU since it does what it's told when in the governed range. But also for consideration is the lives of both PTG and FCU, as they mature the scheduling becomes less precise (though within prescribed limits). Poss, though doubtful, could be air in the torque gauge line? Would be very interested in anyone else's hypotheses - VFR

[SuperF]

fokker

it can depend upon what you are comparing it to. Also depends if you have a Bendix or Ceco, the ceco being slower to respond than the bendix i believe.

If you are trying to fly it like a 500, then the response will probably be called slow, however if you fly it like a 47 or 205, then it should respond pretty well. We don't have any problem with RPM droop, however we also fly ours like a big ol 205 without sudden collective changes and it all works out fine.

If you are getting RPM droop from gentle collective changes then go see your engineer.

[RVDT]

Most of which can be rigged out unless the PTG is a duffer.

You should actually see a slight increase in N2 from flat pitch to hover as normal.

This is "droop compensation". Without it the following applies -

Droop has many uses and applications in the control of engines.
Without some form of droop, engine-speed control would be unstable in most cases.

- Droop is defined as a decrease in speed setting at the load increases.
Droop is expressed as a percentage of the original speed setting from no load to full load.
The normal recommended percent of droop is 3% to 5%. A minimum of 2.5% is required to
maintain stability in a speed-droop governor.

If, instead of a decrease in speed setting an increase takes place, the governor is showing
negative droop. Negative droop will cause instability in a governor.
In a system without droop, a load increase will cause the engine to slow down. The governor will
respond by increasing the fuel until the engine has returned to the original speed.
Due to the combined properties of inertia and power lag, the engine speed will continue to increase
beyond the original speed setting, causing an overshoot in speed.
The governor again will respond to decrease speed to correct for the overshoot.
It will over-correct the speed in the other direction causing an undershoot.
This overcorrection of speed in both directions (instability) will amplify until the engine trips out on over-speed.

This instability problem can be eliminated with droop. As the load increases, the speed setting is decreased.
When the governor moves to correct for the speed decrease caused by the increased load,
it will be correcting to a lower speed setting. This lower speed setting prevents the speed from overshooting.

Clear now? :p

[fokkerpilot]

It is Bendix.

Can the droop be adjusted on the PTG?

Thanks

[owen meaney]

Fockerpilot asks can droop be adjusted on bendix system.
There is a precise rigging procedure in the Maintenance Manual. Tell your MRO what the symptoms are, and they should be able to identify whether it is a rigging or PTG problem.

You should be able to fly the JetRanger and LOngRanger without constantly using the "Beep" switch.

Bell have a website where you can ask questions about their product and receive advice to rectify issues. Bell publications and access to web data is free.

What Fockerpilot is referring to in post 1235 is static droop, which is acceptable in the hydromechanical governing system on the Bell 206 series. If it is more that .5 to 1 percent before it resets back to the selected RPM(100%), further investigation would be warranted.

[RVDT]

The PTG itself cannot be adjusted.

The rig of the droop compensation can and should be checked with the AMM as a few errors can be made although it may not be worth it.

PTG's get worn out, sticky through lube drying out, the jet faces and levers get worn through dirt. There is/was a jet cleaning procedure but ..................

Bendix PTG's commonly don't get to Overhaul period.

I would look at the history of the unit with respect to how much dirt, smoke or other pollutants it has eaten and also the calendar time installed on the aircraft
which would reflect condition of the lubricant.

All of which could point to a bad PTG. They run on air after all.

[Saint Jack]

Super F is absolutely correct, don't pull it (the collective) aggressively - why do you? Similarly, go gently with the cyclic - smooth movements will greatly reduce the wear and tear on linkages, mounts and the airframe in general.


Having said that, the problems detailed by both Bell_Flyer and fokkerpilot are broadly similar and, as mentioned by others, the first thing to look at is the N2 rigging (provided the arm on the FCU is making firm contact with the max power stop it's unlikely that N1 rigging is the problem) One important point of N2 rigging is that the arm on the PTG must not touch either stop with the collective full down and beeped down or full up and beeped up. Check that the entire N2 control linkage is free of excessive backlash, replace any defective part/s.


Next, look for will be loose pneumatic lines on the engine, check for tightness and, if necessary, check the flares for cracks. Remember that pipe flares should align properly with the mating fitting - you're allowed to bend the pipe (gently) to ensure proper seating - a misaligned pipe is a strong candidate for cracking at the flare.


Following that, the next step should be to remove, check and clean the P3 filter. Also, as RVDT said, the PTG can get dirty and on some P/N's you can remove the Px and Py bleed orifices for cleaning - this is a very simple procedure but do one at a time to prevent mix-up.


If you find the Px and Py bleed orifices are dirty and the P3 filter requires cleaning and the engine is sometimes slow/difficult to start, then there's a
high probability the FCU start de-rich bellows bleed orifice also requires cleaning. Note that this is only possible on some FCU P/N's - check the MM.

[vfr440]

I thought that Px & Py bleeds were installed in the FCU, NOT the PTG. They absolutely are!)...............:confused:. (But absolutely right to do them one at a time - given which I have never had any quantifiable improvement in doing so. Such a hassle to remove the FCU in the first place) I checked my reference manuals, and my 'experience notes' and stand by this statement (!) - VFR

[FH1100 Pilot]

If Bell Flyer were in a 206B I would say his problem is a bad (what the mechanics call a) "double-check-valve." Since I'm not sure the C30 has such a device I will not suggest that's it, but any time I've gotten such torque fluctuations in a C20 it was the double-check-valve going bad.

[Saint Jack]

vfr440 is absolutely correct that the Px and Py bleeds are in the FCU, my mistake - I haven't worked on this engine for some time. But I do remember removing and cleaning a bleed orifice (Pg?) on the PTG and that it can be done without removing the PTG from the engine - check the engine MM. Similarly, cleaning the double check valve, as suggested by FH1100 Pilot is a simple task but it has to be removed from the engine.


My reference to the P3 filter was also incorrect, it should of course be the Pc filter.


Bell_Flyer and fokkerpilot : let us know the outcome of your troubleshooting so that we can all learn.

[Washeduprotorgypsy]

Just listening inattentively in the back benches here.......

But the topic reminded me of a tour from hell in a remote area with a newly acquired bucking bronc of an L3.......

First of all is the torque fluction REAL and ACTUAL, that is; felt in the seat of the pants by way of yaw, heard, and correlated by a bouncing nr gauge?

Or is it just the torque gauge itself bobbing up and down 10 percent or so?

If you think it's ACTUAL. Start with the easy stuff mentioned so far PTG, FCU. But on the c30 don't rule out the combustion liner can. Yup, the combustion liner. Had very similar actual torque bob with a beat of about 40-50 beats a min.
Changed out parts willy nilly and low and behold it was the combustion can had shifted minutely causing a surging flame pattern.

If it's just the torque gauge and all the air has been bled from the system repeatedly then hate to say could be a gearbox issue with torquemeter system hydraulic issues.
Good luck

[RVDT]

DC valve is only fitted/required on the 206 Series from memory (fading a bit as haven't worked on one for about 20 years - FADEC these days!)
and it is there to stop the PTG reacting to the torque fluctuation inherent in the 2 blade rotor.

[Saint Jack]

RVDT I too seem to have a failing memory, mine is telling me that the second accumulator was an addition to the 206 engine installation to dampen out torque fluctuations. The 206 configuration being and accumulator on both sides of the double check valve.

[vfr440]

Hey Washed up (love the handle!)
Your recall is better than mine, NOW I remember about the C30 liner(!), though I never encountered a snag which required such action. Nice one :) There was also a requirement to monitor/retain the shims under the fuel nozzle too, but can't remember why - starting problems maybe?


Cheers - VFR :cool:

[Washeduprotorgypsy]

Thank yuh, thank yuh very much. Hey what are pprune noobs for?

In interest of furthering the "Alzheimer's support group" or God forbid the "pass it on" spirit. I'll chime in again.

Fuel nozzle shimming in regards to torque surging , mmmmm I dunno? But it definitely makes the difference between a fizzle-Boom! and a symphony at light off during starting.

In regards to the suspect combustion liner, it's getting pretty foggy but I do remember upon removal there were no visible cracks, defects, oxidation marks to differentiate it from a healthy liner. Well by having a quick look anyways. Lots of unseen black magic going on in there with temps, press, flow conditions and contraction, expansion so it's not completely surprising a liner could be the offending culprit.

Somebody mentioned pulling the collective fast. I d say when acquainting yourself with an unknown unproven machine definetly a good idea to "pop the clutch" and shoot a couple of power recovery autos. Just to be sure when you re flittering around in the hills and your judgement comes up a little short the power doesn't. Lots of unseen parts holding your ass in the air, and component duds never get passed around:rolleyes:. Always nice to know the compressor, bleed valve, FCU,PTG, rigging etc. Etc . Are all up to the acceleration task before
Loading the station wagon up with the kids.

That's all I got. Happy flying.

[Carbonok]

Hi guys.
First, very sorry for barging in here...
I've been looking for B206 drawings showing the early fully faired U/C legs and straight topped pop out float skids, like the JR in 'The Spy who Loved Me' and many others in this thread (thanks for the pictures all of you).
I'm a modeller and have longed for a really scale Jetranger for quite a while.
I first wrote to Corgi in about 1974 asking them to make one.
They did, but even as a 9 year old I could see the flaws.
See the 'Stromberg' and 'Chopper Squad' Corgi toys.
Now, in 2015, I have a really good fuselage and flybarless chassis with the T/R on the port side. Yes, this one will fly.
The windscreen is pretty accurate but the 'snout' needs a little work.
The professional modellers (plastic/ die cast) don't often get these shapes right.
I have not yet found a drawing showing the older high skids, nor a photo' that I can scale from (I need a straight on side and front view).
By now you must be bored!
After all there are many superb scale JR models out there.
However this one will be just 12'' long.
It will be as true to scale as I can make it (with your help!) and will fly in my lounge.
Once again, please help!
Many thanks and kind regards.