Bell 206: JetRanger and LongRanger

[ProfessorFate]

Hi.

Where can I find an online copy of the emergency procedures for the Bell 206 B III. I've got a job app/checkride coming up and I don't have a POH until after I get the job.

I do have a transition book, but for some reason it doesn't have the emergency procedures in it.

Thanks!

[SASless]

No worry young man, Air Log gives you all that in the new guy orientation....also with the looming strike....they are going to be very short of pilots thus I would imagine Management will provide ample opportunity to redo the ride until you pass.

[The Nr Fairy]

Prof:

If you want, I have a 12 page check list which I could scan in with normal and emergency procedures, but it's brief. Send me a MP or email if you want.

Otherwise, if you are near an airport which has a 206 based there, perhaps asking nicely to sit in and run touch drills may help ?

[SiClick]

I am looking to find an approved STC for the Bell 206, to put a Datcom wired to the Collective Lever, and the engine that will allow me to record airborne time.
Would appreciate any good steers!
Thanks

[overpitched]

Don't know if this is of any assistance but some of the Garmin gps units have a trip timer that only starts counting when the unit is moving. It won't record hover time but it certainly does a good job of keeping track of your daily flight hours if you are doing a lot of hops.

You just zero it at the start of the day and then read off the hours and minutes at the finish.

[John Eacott]

I've got Datcom clocks wired to the collective in two JetRangers, using a local EO (Engineering Order). Haven't heard of an STC to cover this, EO is fairly straightforward. Just remember to re set the timer after the collective has been pulled up for a day whilst in maintenance ;)

[206 jock]

My 206 has a Datcon in the cockpit that's collective linked. I bought it like that, so presumed it was 'normal'.

That's an extra feature I'll advertise when I come to sell it!!

[widgeon]

Supplemental Type Certificate

STC Number:
SH625NW

This certificate issued to:
Weyerhaeuser Company

STC Holder's Address:
1020 26th Avenue, N.W.
Gig HArbor WA 98335
United States

Description of the Type Design Change:
Installation of collective torque tube actuated hour meter switch and an engine-out audible warning system.

Application Date:


Status:
Issued, 06/28/1978

Responsible Office:
ANM-100S Seattle Aircraft Certification Office Tel: (425) 917-6400
TC Number -- Make -- Model:
H2SW -- Bell Helicopter Textron (Canada) -- 206A
H2SW -- Bell Helicopter Textron (Canada) -- 206B

Full Text of STC:


Comments

http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgSTC.nsf/MainFrame?OpenFrameSet

[SiClick]

Thanks for all the help, wonderful thing this PPRUNE!
The STC above is for a company that is not interested in allowing it to be used elsewhere (so I am told!) I therefore still need to find annother. The modification is very common, but its normally carried out as a Local Engineering modification, which apparently is something different to a Supplementary Type Certificate (I am a pilot not an engineer!).
If anyone has any bright idea's for simple devices that I can fit to record flight time, for which there is an STC I'd be grateful
Thanks :O

[Shawn Coyle]

Not sure that an STC is needed - it doesn't interfere with the flight controls, change the performance or handling, and doesn't affect the electrical system. In the US, a form 337 would suffice, I'm sure.
Not sure what your local regulations require, but don't be forced to put in an STC just because that's the answer the local regulatory authority says you need. Ask why an STC?

[SiClick]

I am working in the Middle East, and the local authority are loath to give any approvals unless it can be clearlty demonstrated that annother competant authority has already approved whatever it is your planning to do (ie an STC) therefore I am stuck!
Thanks:O

[206 jock]

I own a 206 A/B with a C20 engine. She's an old girl but flies well

I'm going thru the painful process of 'overhauling' my transmission and M/R head. My old trans was the -015 3 stage sort, so I've sourced a -029 (BIII) unit to replace it. (Anybody need a -015 trans with 25 hours left on it??).

Took a risk on overhauling my own head (a -021 'small' unit): bad mistake! Yoke and grips both shot as well as timex pins fittings etc. I reckon parts alone are c$22k. As I understand it, if I fit them all, I'll get 2,500 hours TBO and still have good life left on the trunnion and grips, so nothing to worry about for a while.

I've also found a -127 (BIII) head with around 2,200 hoursTBO for $26k: one benefit of this unit is that it's bolt on.

So, I've got three choices:

1) buy the -127 and sell the good bits out of my old head, and swallow the labour so far as 'experience'
2) buy the -127 head and continue to overhaul mine and sell it on
3) carry on with the overhaul on my head and stop thinking about the -127!

Any advice?

Question is: does having a 'BIII' drivetrain give me any other advantages for when I come to sell the machine, or upgrade it? Eg, could I fit a c20B at some point when I've put more money in the piggy bank?

[sprocket]

Have you considered what the throwaway life remaining is of the existing components in the B3 head as opposed to just the O/H life? There could be more expensive parts due for replacement because of life expiry at the next O/H too. You do the sums.


If the T/M and head are the only B3 components that you have in the drivetrain and you still want to achieve full B3 status then you would still have to upgrade the ….
FWU
Cooler blower
T/R driveshaft
T/R gearbox
Tailrotor assy
Some rear fuselage stiffening and associated downtime.

There is a BHT service instruction that gives you all the details but I cant remember its number.

[belly tank]

Ive just ordered a set off straps for our 206, no problem however, can anyone care to comment on bell ever cancelling the A.D is it really neccesary for the replacement on the due time reqirement, or is bell having too much success with the ongoing sale of tt straps.

curious???

[Giovanni Cento Nove]

Are you replacing them on flight time or calendar time? In days past you used to get a credit for the calendar life remaining. Try flying with either or both failed and get back to us!!

[belly tank]

We recently purcahsed the 206 from overseas and they only have 300 hrs flown off them, calendar life is up but the previous owners didnt use the machine a great deal, since weve owned it about 3 months weve put 100 odd hous on it. bell said today they will give a rebate of 15% with straps that have over 600 hrs remaining.

[trackdirect]

Belly Tank

TT straps have hourly and time limits imposed on them because they are a flight critical component. If your straps go you go too!!
They had the life limit put on them due to quite a few failures early on in the JR's life.
Straps are constructed of many thousands of windings of stainless steel wire these windings covered in a plastic coating.
These windings are susceptible to fatigue that is why there is an hour limit, they are also susceptible to corrosion believe it or not that is why they have a calendar life.
If you want any more information talk to the guy that put your red machine on the register he is quite knowledgable.

Some military Bells dont have a life limit on the straps but thats just the military way.... just another number.

[spinningwings]

...If your TT straps have exceeded thier calender life ....change them ASAP ... or we might be reading about you in the "crash comics".

The straps are very robust BUT are subject to internal corrossion (?????) and if they fail its all over mate.

Due to their being sealed up in an epoxy type covering theyare not able to be visually inspected they are NOT an "on condition" item.

The straps are very similar to those used in the Bo105 Bk117 series of a/c and I think the only head failure (??) ever recorded on the Bo105 was from a TT strap failure !!!!

[belly tank]

SPINNING WINGS

...If your TT straps have exceeded thier calender life ....change them ASAP ... or we might be reading about you in the "crash comics".

I look after our machines impecably, and i certainly dont fly with components out of date or hours i was mearly asking a question

[vaqueroaero]

Ok here's the situation:

We are at 9000 MSL in a Jet Ranger, crossing some mountains and giving sufficient ground clearance over some condor sanctuaries.

We notice that the fuel pressure has dropped to just above the red line. We then descend to around 6500 MSL and the pressure goes back to the middle of the green. Just out of interest we start to climb again and sure enough the pressure starts to drop again. There are no fuel pump lights illuminated and on landing we check both pumps and they are working fine.

Has anyone else experienced this? Is it normal?

I'm still waiting for a reply from Bell, but any answers / ideas / suggestions would be appreciated.

[Giovanni Cento Nove]

Like the mercury in Torricelli's barometer the column of fuel from the tank to the engine will appear heavier at a lower barometric pressure. Sea level standard baro 760 millimetres, 9000' its about 543 millimetres, a difference of about 220 mm or 4.4 psia which is probably the difference you are looking at.

Hence the instruction in the FM ref "Operations with one boost pump inop above 5000'" or somesuch.

Makes sense to me.........

[mikeferg]

I think that is NOT normal. It sounds to me like you have a slight leak in one of your boost pumps somewhere, or a weak boost pump. I'd check all the boost pump lines, and look under the rear floor around the fuel tank, ejectors, etc. And I'd definitely pursue Bell to find an answer. It doesn't sound like it could be your main fuel pump, because it doesn't produce enough pressure above 6,000' to keep it above the redline.

When you do your boost pump checks, does one seem stronger than the other? Can you find a place to land at 9000' and perform a boost pump check to see if one of your pumps allows the fuel pressure to fall below redline? My guess is that one of your pumps is doing most of the work, or you have a slight air leak somewhere.

[Ascend Charlie]

Well, for starters the main fuel pump (engine-driven) doesn't produce pressure (except into the FCU), it sucks. The pressure gauge measures only the electric boost pumps, and as GCN says, the higher you go, the less assistance they have from air pressure.

With both pumps out, the engine-driven pump cannot suck the fuel if you are above (geeze, what were the numbers??) 5300'?? The problem produces its own solution, because the helo rapidly descends back below that height, all you have to do is restart the engine and hope the ground is somewhat lower than that.

An "air leak" ? A fuel leak to cause a loss of pressure will spray fuel everywhere. An air leak happens in things like a 76 where there are no pressure pumps, just suction, and it is safer to have air come into a line than to have fuel come out of it.

[Giovanni Cento Nove]

Granted one of the boost pumps may be weak but you would have checked that in the pre takeoff checks hopefully. As the pressure gauge only measures the pressure of the "best" pump, pop each breaker one at a time and see what the pressure is. mikeferg this is a ShortRanger so there are no ejectors or lines running along the floor! We won't talk about the L that's a can of worms on its own.

I think the 250C20 is OK with a pressure at the main pump inlet of 0". The airframe manufacturer probably recommends otherwise though.

AC, Air leaks are just as bad as fuel leaks, flameout for one and a fire hazard for the other, take your pick. Bendix equipment is fairly tolerant and will pass dirt, water, nuts and bolts, some bubbles, but not the gear that used to be around made by CECO!

Vaquero,
Of course you will post Bell's response won't you.

[407 Driver]

Sounds pretty much normal Ops from any 206 that I've flown, I have 10,000 on type, mostly at altitude.
There is a procedure outlined in the Maintenance Manual to check for air leaks in the fuel system ...basically run the aircraft on the ground at 100% Nr for 2 minutes with BOTH boost pumps OFF (and at a low fuel quantity), the Eng driven pump sucks, so without boost pressure, it Will find any air-leaks ! This test should be done after any In-Tank maintenance.

[that chinese fella]

Had a similiar problem and all basic fault finding found nought. Short of putting in new pumps I cannot suggest anything additional.

[sprocket]

Sounds like a good time to check your fuel system, in case there is an underlying problem. (When was the last annual done?)

Another possibility is the check valves. There is one on each boost pump. The pumps need to be removed to clean the check valves but may be worth it in case there is contamination building up.
If one boost pump is producing a lower pressure than the other one when operated individually, then the check valve in the "better" pump could be the culprit. Also have the lines checked for leakage while the pumps are out.

Most capable mechanics/engineers should be able to figure the problem out fairly quickly.

[sycamore]

Might be worth getting engineering to back-blow( from the tank !) the vent line to ensure it`s clear of spiders /muck/moisture. I presume at 9000 ft you were not above a freezing level in CA?

[Giovanni Cento Nove]

Without regard to the "limits" being approached, I still maintain that the change in pressure with altitude is "normal" as per 407Drivers comments.

407Drivers comments re testing of the system is definitely a requirement on ALL "L" models. Ever wondered why one Boost pump is hard wired in L1 thru 4?

[vaqueroaero]

Thanks for all the replies.
I'm expecting a call from Bell today, so will post the reply. The first guy I spoke to over there suggested the change in pressure with altitude. However the question on that is that if we had gone higher, would it have dropped below the red line? If we were only at 9000 MSL and near the limit how do people get upto 14-15,000? The temperature up there was well above freezing. She's due for a 100 hour in about 35 hours.

I personally think there is more to it than air pressure change, but time will tell!

[JHR]

If one pump is weaker than the other it may be a check valve stuck in the open position. This will recirc fuel from the strong pump back thru the weak one. If the pump pressure difference is greater than 4 to 6 psi when the circuit breakers are pulled one at a time it's the likely culprit

[that chinese fella]

Boost pumps are very sensitive to voltage. Try, as a fault finding exercise, winding up the Voltage Regulator setting a bit and try that.

[mikeferg]

I'm expecting a call from Bell today, so will post the reply. The first guy I spoke to over there suggested the change in pressure with altitude.
Most definitely let us know what Bell tells you. I'm going to stick with my original theory. Something isn't right. A slight drop in pressure I could live with, but from mid-green to just above the redline suggests you have a boost pump problem somewhere. JHR might be on to something. His post reminded me, I've had a stuck valve before, and it did cause one pump to recirculate. Also, if you do have a slight air leak, it won't cause a flame out, but it will cause the offending pump to show a pressure drop.

Any chance you could borrow a boost pump from another operator to use on your aircraft to see if you can isolate a problem?

[StevieTerrier]

Giovanni -

If the boost pumps operate at a constant RPM, and the pick-up pipe is always completeley submerged in the fuel, then in theory they should always transfer the same amount of fuel regardless of the atmospheric pressure. And if thats the case, then there should be no drop in pressure sensed by the transducers which feed the boost pump gauge, regardless of altitude.

Or am I missing something?

[Giovanni Cento Nove]

Steve,

It would appear so. Without going into depth have a look here..........

Basic pump theory (http://www.pumps-in-stock.com/pump_theory_basics.html)

Also read up on centrifugal pumps which are NOT positive displacement.

I don't know what values Vaqueroaero is getting I am just theorising as to why there is a change with altitude. I quoted a differential of psia, and in the aircraft you are looking at psig which does not account for changes in atmospheric pressure.

Hope this helps.

[vaqueroaero]

Latest update: Bell has their 'fluid engineers' on the case.......watch this space.......

Thanks again for all the input.

[StevieTerrier]

Giovanni - thanks for that. Seems I was only missing the unimportant basic principles on how these pumps actually work....
Probably explains my miserable Grade 6 Physics "O" level result!
:ok:

[vaqueroaero]

For all those who asked me to post Bells answer to the fuel pump pressure here it is.
According to the boffins at Bell the pressure drop was caused purely by the drop in atmospheric pressure. As long as the pressure is in the green there is no problem, if it drops out, then descend until the pressure rises again.

[Giovanni Cento Nove]

As Mr Torricelli said - We have made many glass vessels ... with tubes two cubits long. These were filled with mercury, the open end was closed with the finger, and the tubes were then inverted in a vessel where there was mercury. .. We saw that an empty space was formed and that nothing happened in the vessel where this space was formed ... I claim that the force which keeps the mercury from falling is external and that the force comes from outside the tube. On the surface of the mercury which is in the bowl rests the weight of a column of fifty miles of air. Is it a surprise that into the vessel, in which the mercury has no inclination and no repugnance, not even the slightest, to being there, it should enter and should rise in a column high enough to make equilibrium with the weight of the external air which forces it up?

Got beer?

[belly tank]

Just to add some info on the TT strap issue, I found this snippet in the march edition of rotor breeze a bell published magazine.

{ Apart from a complete new rotor system design eliminating the tt strap altogether, the latest design consideration is out in the field today and uses a steel alloy that is more resistant to fretting corrosion. the first field straps have been returned for consideration and conditional and destructive testing, and the final phase of field evaluation has begun.

if this evaluation is succesful Bells intent is to introduce the new strap and extend the calendar life to 36 months and possibly more. }

it also went onto say that military OH-58 operate safely with no 24 month calendar life, bell advised the military of the 24 month life however the forces control the type certificate and elected not to impose the 24 month life limit.

i guess we will have to wait for the outcome of the testing phase!

cheers
BT

[Warren Buffett]

Belly Tank - the incredible thing about all this is that the problem was identified in 1976 and in 2004 we are still waiting ....

I thought the IRS was bad with refunds.

[helimatt]

What does a new set of straps cost?

[sprocket]

The calander life is the main draw back on the strap life. Been a while for me but the straps where about 2-3 grand each (x2) plus a day or so out of the air while the job is done.

[Right Stuff]

Sorry to be an all round nuisance but can someone briefly explain what a TT strap is? Thanks in advance.

[the coyote]

It is a "narrow holding pattern" shaped part that takes a big bolt through either end. It consists of lots and lots of very fine wire windings. It anchors the rotor blade to the rotor head, absorbing the 9 tonnes (or so isn't it?) of outward force from the blade while still being flexible enough to allow it to twist as the blade changes pitch angle.

[sprocket]

Right Stuff: The coyote has described the TT straps pretty well, ie "it anchors the rotor blade to the head/hub." The TT stands for Tension Torsion. The outward forces (centrifugal) of the blade create a tension loading on the straps and when the blade pitch is changed the straps twist with it to allow blade movement, aka torsion.

When the helicopter is flying, the straps are working hard in both tension and torsional directions. The stress and constant movement of the windings would have to be the main factors in the life restrictions of the TT straps, although Bell stipulate that once a strap has been fitted to a helicopter the calendar life commences even if it does not fly.

[rotorrookie]

I heard some years ago about 206 that lost one of the two blades in flight and then of course the remaining blade ribbed the main gearbox and the turbine out of the fuselage.
I think it was in N.Y. not sure though. Was it because of TT strap failure or what?? Does anyone remember?

[Right Stuff]

Many thanks chaps, puts it all in context now!

[Findon 40]

Re T T Straps

The AAC lost a Gazelle Nov 01 due to a Tie-Bar failure(TT strap),At that time it had only done about half of it's life (5000hrs),it had failed due to corrosion leading to the breakdown of the wire windings.Since then,Tie-bars before a certain date were scrapped,new Tie-bars now have a life of 5yrs/1500hrs with a 2yr/600hr inspection,including the new redesigned Tie-bar...................i know people always ask why do they have to be replaced if they are only due on date......but i had to watch the agnuish that a work colleague put himself through,wondering if anything he could of done could of prevented the accident(He had carried out the flt servicing on th A/C the night before),plus the loss of the pilot.............something i would not wish on anyone.............

[CRAN]

Quick Question folks,

How heavy is a single Jet Ranger Main Rotor Blade?

Cheers
CRAN

[sprocket]

Vaguely remember they are around the 60lb mark but its been a while.

Maybe we could have a sweepstake on it? :\

[407 Driver]

I'll guess that they are a bit more, somewhere more around 90 Lbs.

I spent an hour searching on the Internet, but couldn't find a thing.

[Chiplight]

Result of 2 minute Google search: :O

Bell 206 BIII Jetranger Pilots Notes ---
The main rotor blades are of all-metal construction, consisting of an
aluminum-alloy honeycomb core, and aluminium skin and nose block. The rotor
blades incorporate mid-span and tip weights that provide excellent
high-rotational inertia characteristics to ensure good autorotative
landings. The assymmetrical ("droop snoot") cross section design of the
blade enables high rotational velosity with minimum vibration and improved
blade stall characteristics. Each blade is twisted 5 degrees, having more
pitch at the root than at the tip, in order to achieve a more even spanwise
distribution of lift. Each blade is attached to the blade grip by a vertical
through-bolt. These bolts have hollow shanks to permit the installation of
lead weights to balance the hub and blade assembly. The rotor system has a
diameter of 33 feet, 4 inches, and chord of 13 inches. Each blade weighs 94.4 pounds.

[belly tank]

407 driver said {I'll guess that they are a bit more, somewhere more around 90 Lbs}

I guess you win the sweepstake on the closest guess!!!

cheers BT

[sprocket]

I hope CRAN didn't take my answer first up. Just wait till I get the Toad who swapped the 9 and 6 keys on my keyboard. :*

[CRAN]

Thanks Chaps,

Thanks for the quick response, thats most useful!

CRAN
:)

[Rocket2]

Cran - we balance said (Jet Ranger) blades & they have to weigh between 42.16 & 43.07 kG when finished

[Winnie]

Chiplight,
Those are for the TH-57/67 blades, NOT for the 206B's as they have 10 degree twist and SYMMETRICAL design...

Just to make sure
(perhaps I'm wrong anyone?)

[Chiplight]

Found a bit more info:

http://www.eng-tips.com/gfaqs.cfm/pid/6/fid/645 (list of Bell airfoils)

Bell 206 OH-4 NACA 0011 mod
Bell 206 OH-58/TH-67 NACA 0012 mod (11.3%)


NACA 0012 - four digit airfoil
First two digits indicate no camber
Last two digits indicate max t/c=12 percent

[46Driver]

Trying to get some information on how they stack up. I've got a few thousand hours in the TH-57 JetRanger but hopefully some of y'all with experience in both can tell me how they stack up. I know the Bell has a max gross of 3200 lbs and the R-44 tops out at 2400 lbs - any more comments on payload, range, speed?
Thanks.

[Vfrpilotpb]

For me it would only be the 206, it feels much easier, and with its turbine thingy rather than the old recip donkey, it sounds right as well,, but then thats me and my thoughts!
Peter R-B

[Ascend Charlie]

Horses for courses.

For charter work, carrying two couples is the norm. In a 44, one of them stays behind, or, more likely, you don't get the job.

No boot is the biggest reason not to buy a 44.

[Warren Buffett]

charlie s charlie - you sure the 206BIII can cruise at 115kts? Mostly they tend to do between 100 to 110, right?

thanks.

[charlie s charlie]

Figure came straight off the Bell Textron Website, hence my large caveat at the bottom of that post!

[imabell]

r44,
3 pax, no bags, not under the seats if you are sensible.

bell 206,
4 pax, 4 sets of golf clubs in the boot. very sensible.

warren buffet. 100/110 kts max with a load generally although some seem to get along a bit quicker.

the r44 has all the good flight characterisics, especially with the hydraulics. the best machine in auto and the 540 sounds great.

no payload stuffs it.:(

[46Driver]

I saw the R-44 II has an extra 100 pounds of payload - is that correct? (max gross of 2500 lbs vs 2400 lbs)

[EMS K-MAX]

no thats not correct

[charlie s charlie]

The Raven II has a 100 lb increase in gross weight, but also a 64 lb increase in empty weight. So you get another 36lb of payload in the Raven II.

[DualDriver]

Being current on both types, (still prefer the 206) I can cruise the 44 Raven II at a comfortable 115kt. Where I am operating, I have had full fuel and pax in the 44 with some power to spare. The extra HP on the Raven II comes in REALLY handy.:ok:

[Phoinix]

We fly 206, JetRanger III, and there is are some problems with the forces experienced on cyclic and collective. According to the checklist, you check the cyclic stick with hydraulic power off. There is no problem prior to take off. But after flying (30 minutes is enough) forces on cyclic are around 9 kg (is ok), forces on collective are from 14 to 20+ kg. That is too much. That only happens sometimes (not depending on flight time at all). Have any of you experienced that too? We tryed fixing that problem, but no succes.

[sprocket]

Sounds like your swashplate friction is high. Have a mechanic ensure the breakaway friction settings are below the max limit.

Have the friction set to the lower end of the friction limit as the uniball can heat up and tighten when being used in flight.

Has the swashplate had new slider bearings put in recently?


.

[that chinese fella]

Technically the swashplate outer ring will not tilt on the uniball during collective application, the whole assembly just slides up and down on the support (assuming fixed cyclic position).

You mention checking of the cyclic on the ground, what does the collective feel like on the ground?

[SASless]

Years ago in Iran...had a similar problem...was the slider ....but then it could be something else as well.

[sprocket]

Yes, if the slider bearings are old, corrosion can build up behind them and tighten up on to the support.

tcf: I dont have a 206 outside to look at, but there is some sort of coupling (either by friction or mechanical linkage) between the collective and cyclic. Lift up the collective lever (blades not turning) and the cyclic will move fwd or aft.

[that chinese fella]

Sprocket,

You are correct, their is a mixing bellcrank at the base of the vertical tunnel (broom closet). I should have been more specific and said if you hold the cyclic still and raise the collective then does it only move up and down without tilting the uniball.

20kg of force seems like a tremendous amount of friction to build up. The suggestion of the slider bearings is a valid one, ceratinly worth checking but it does involve removing the swashplate.

Good luck

TCF

[PPRUNE FAN#1]

As mere pilots, there's not a lot we can do to troubleshoot a problem with our aircraft. The best we can do is thoroughly explore what's happening and then describe that to the engineers who will then take the appropriate measures to correct it.

I'd start with a check of all controls with the frictions completely off and the aircraft shut down. First thing I'd wonder about: Is the collective friction really completely off? I've seen pilots twist the knob in the "off" direction so hard that the friction started to come back on. The first thing I would check is that the collective friction was not causing *any* binding.

Do the cyclic and collective move through their entire respective ranges with the same amont of force? I might even have an engineer remove the seats and seatpans to ensure that the collective linkage is not binding on anything (wire bundles, errant spanner, etc) between the stick and where the linkage goes into the broomcloset.

Once the aircraft is started and at *idle* (you know, around 62% N1), it won't hurt anything to momentarily lift the collective up a ways (you don't have to pull it *all* the way up but you could) as long as the cyclic is centered. You'll find out how the linkage feels with the hydraulics on. Are the forces constant? Now do your hydraulic checks by the book.

Take off and fly. When you start to feel the binding (I'm assuming from your original post that it is not constant), then fly at 60 kts. You can make fairly large control movements here without too much fear. So feel the cyclic servos. Remember the "X" pattern (left/front to right/rear and right/front to left/rear). Don't be jerky or abrupt, be smooth! But do move the cyclic enough to know that the servo is actually moving. Are either of them binding? (You probably don't want to do that with paying passengers onboard.)

If you're satisfied that the cyclic is okay and not part of the problem, then focus on the collective. You can make some big movements from whatever power is necessary to hold 60 kts to 100%Q (or limiting TOT, whichever) and down to flat pitch, then back up to max power. Is the force needed to move the collective different from when you were on the ground? Is the force needed constant? Does it change as you move it through certain areas?

Once these questions are answered, you can go to your engineers with an informed, informative discrepancy write-up.

[Fatigue]

Hey guys, situation, first flight of the day, reach 50% N1, does not accelerate, hung start, observe start times, close throttle, try again, 2nd start, lay a months money that this time it will work, always does on any of the 206's in the fleet.....I know that the hung start is usually lack of fuel in the combustion chamber, but can anyone shed some light on why that 2nd start, in my experience(hundreds of starts on the 206) always works the second time around?
Appreciate any information...
Regards,
Fatigue.

[CyclicRick]

I think it's because it's a woman and American, she was even Christned Allison :hmm:

[the coyote]

Hmmm, hung, can't get it above 50% in the morning, sounds like a Freudian problem to me...:E

[belly tank]

Fatigue,

How's the battery in the ship?...it may be like your namesake!! it may be a bit lazy?..make sure you have a good battery or ground power for the first start of the day if you can get it.

[that chinese fella]

Fatigue,

Need more info.


Internal or external power?
Type of battery/s?
Bendix or CECO?
OAT?
N1 when throttle opened?
Any delay between throttle open and lightoff?
1st TOT peak and at what N1?
2nd TOT peak (if any) and and what N1?
Time to idle or hung point?
Fuel Nozzle maintenance practices?

All info helps.

Cheers

TCF

[Fatigue]

Internal or external power? We always use 28 V GPU for start
Type of battery/s? 24 V Sealed Lead Acid
Bendix or CECO? Bendix
OAT? Average 15-20 degrees C
N1 when throttle opened? 15%
Any delay between throttle open and lightoff? No!
1st TOT peak and at what N1? TOT Can't remember, N1 stopped at 50%

2nd TOT peak (if any) and and what N1? TOT can't remember, second start successful (as always)
Time to idle or hung point? Approx. 30 seconds
Fuel Nozzle maintenance practices? Will have to ask maintenance!

We have several 206's, and on the odd occasion, we have a hung start, the second start is always successful, and I am just intrigued as to the reason why. Many thanks, Fatigue

[that chinese fella]

I take it that this happens on a few of your 206 fleet, not just one troublesome machine (judging from your 1st post)? If so, that is intriguing.

When you say a 28V GPU do you mean a proper GPU or just some batteries hooked up together in a wheeled box?

Do you have the same problems if you start on internal batteries?

Can you note the 1st and 2nd peak N1/TOT figures next time you start one and let us know? In the Bendix FCU there are 2 adjustments that can alter these parameters so which ones to make, if required, rely on accurate reporting to the gingerbeers.

TCF

[407 Driver]

The Bendix system was never my favorite, I liked the Ceco system better, even if the Nr wandered around a bit more.
TCF has the correct thought process, check the temps and N1's on the 2 surges, it will tell you where the start "notch" is, and can be adjusted to provide more of an acceleration boost in the latter stages of the start.
A good 206 start is probably hotter and quicker than you'd imagine....I forget the Alison figures, but 825 C comes to mind. I may have that old memo at the office, I'll check tomorrow.

[trackdirect]

Do you regularly comp wash the heli without either removing the PC line to the filter or shutting the line off with an AA comp wash kit??
If the PC filter is a bit grubby it can become restricted with a bit of moisture and the start will hang at 40-50%, but on the second try will start without a problem.
Get your engineer to clean the filter ultrasonicly and see if that fixes the problem.

TRACKDIRECT

[PPRUNE FAN#1]

It is an interesting peculiarity that some 206's will hang on the first attempt yet start fine on the second. I've got to go with "trackdirect"- it's most likely moisture in the PC filter or other air lines that gets dried out by the heat of the compressed air during the first start. In my experience, whenever the engine would hang on the first, I'd let it sit there for a few seconds (nothing protracted) just to make sure to get some heat into the components before making the second try.

[Fatigue]

TCF

We use proper GPU,s and have around 28v indicated on the cockpit voltmeter,and yes it is no particular aircraft, never had a hung start using the battery yet but we rarely do them...will try to remember the figures next time....

407D.

Our aircraft start well below 825, 650-750 is the norm,800+ sometimes,....although I watch one peak at 920 the other day during some sort of maintenance...

Moisture sounds quite feesable as we start very early in the morning..

Thanks Gents for all your information..

Regards
Fatigue.

[that chinese fella]

Keep in mind that the Pc filter should be inspected and cleaned every 300 hours according to RR.

Filling it up with Compressor wash detergent if you dont disconnect the line or close it off with an AA kit will certainly prevent the engine accelerating but usually will continue with same fault until the detergent is cleaned out. I would be suprised if many engineers made that mistake too often.

All of these hung start problems are not normal and a systematic fault finding approach, starting with accurate ntoing/recording of start parameters, is the first step.

TCF

[407 Driver]

Fatigue, those starts sound a bit cool for a 206. I was busy today, so never got to finding that old Alison article, may not have time tomorrow either, but I'd suggest a boost of start temp may be in order...perhaps not to solve the problem now, but to cause less stress on the engine. Slow cool starts are not good for a turbine.

[that chinese fella]

The documents that 407 is referring to are Allison (now Rolls) Commercial Service Letter's (CSL) # 1176 and # 1192 (for the C20 series).

The first one is titled Optimised Start technique for the C20. Without reciting the whole thing, of note is their definition of a good first start - "one taking less than 25 seconds form the introduction of fuel until the engine reaches ground idle". Overall a very interesting read.

#1192 is a 20 page effort about troubleshooting, with some excellent info.

Your maintenance people should have these in their tech library or contact Rolls themselves for copies.

[407 Driver]

You beat me to it, ...Yes it is CSL 1176, dated 15 December 1992. It also states that a C20 engine may reach 820C on an optimized start.

If you require a copy, I can fax it to you....

[Shawn Coyle]

We have a C20B that is very slow between 50 and 58% on the first start of the day. I had also seen this many years ago on a 206 operated at the Bell factory (who did everything they could to find the cause, to no avail)
Worse on colder days than hot days. I did some checking with a friend who is a very experienced ex-tech rep from the manufacturer.
He explained that the problem is due to cold fuel and that a strip-down of the fuel control would solve the problem, but that this was probably not cost effective. Just live with it.
As it added only about 5 seconds over the normal start time, he didn't think it was going to affect the starter for over heating, as at the RPMs it was running at, the current draw was pretty small.
So we live with it.
If the N1 genuinely hangs up and doesn't accelerate at all, that's a different story.

[Grainger]

OK gang, I'm starting my JetRanger conversion (Yee Haa :D )

Currently R22/R44 rated.

I've already got the hang of "stick-your-thumb-on-that-button-and-don't-let-go-whatever-happens!"

Any further advice please from all you experienced B206 jocks would be very gratefully received .

Cheers,
G :cool:

[206 jock]

You called?

The conversion is a doddle: it really is a delight to fly. As you've already figured, it's the start that's exciting - the only other thing to remember is how long it is (OK, that's a bit simplistic, but not far from the truth).

Once you're converted, here's 4 golden rules

1) Be prepared to smell faintly of kerosene at all times

2) Be prepared to look down your nose at all Robinson helicopters

3) Be prepared for very large bills whenever it goes in for maintenance. If they're small, celebrate!

4) Enjoy it!

PS Wanna buy one? Just contemplating buying one in from the States, so my nice one might be coming up soon:ok:

[BlenderPilot]

First of all don't worry, the 206 must be the easiest helicopter to fly around, and please don't stir the ciclic as many people who come from Robinsons do when they first step into a turbine, only apply as much input as needed and "leave it there" controls are much more precise than in a Robbie.

1. At a given GW, aprox. Aprox. 10% more power is required to hover OGE than IGE.

2.- Aprox. 1% TQ is equals about 30 pounds of stuff you can carry

3.- Aproximately 3% TQ is lost with each 1000 FT gain in altitude

4.- Aprox. 1% TQ is about 4 SHP

5.- The helicopter should be level and CLOSE to the ground before NR is below 70% during practice autos

6.- Aprox. 1% TQ is lost with each 1.5 degree Celsius rise in OAT

7.- It will land on a steeper slope with the right skid upslope, when its balanced properly.

8.- It its starts a little hot and you need to start right a few minutes after you just shut down, opening the engine covers will help a lot in cooling down before the next start.

9.- Watch your pedal authority when at altitude, and please don't over TQ.

Have fun.

[SASless]

all good advice from those who posted above....and the most important thing to remember...whatever you do....never...never ....never fly a MD 500D or E or F.....or you will realize how much money you wasted on the 206 when you could have flown a really fun machine....with the same engine. A machine that goes like the clappers...turns on a penny....loves grass in the overhead vistas.;)

[Gomer Pylot]

But which is massively uncomfortable for passengers and doesn't have room to carry your briefcase. There's a good reason none are flying in the oil patch. They're fun for the pilot, but they don't pay us to have fun; they pay us to haul payload, and that machine won't do the job.

[Grainger]

Thanks guys, a wealth of knowledge out there ! Keep 'em coming !

Another flight today - I'll try not to stir the cyclic ! - I'll let you know how it goes.

Cheers,

G :cool:

[CyclicWaggle]

I'm gonna be doing the 206 conversion in a few weeks (fingers crossed), once I've passed my flight test too so all these little tips are great. I've been told by my instructor that the Snotrangers are all too easy to over-torque when they're a bit heavy and you're not careful with your left foot. Is there any specific technique to use when you're a bit heavy and you're likely to run it up to the redline (hovering crosswind - LTE, high altitudes)? :oh:

[belly tank]

Cyclic waggle , Grainger

Just a tip, when your near mtow or operating at high altitudes on approach into a pad, make sure you have a nice rate of descent not to steep if you have the terrain to do so, get that power in early to spool up the turbine dont leave it till the end when you decide to pull the collective up under your armpit!! it wont be there the turbine will take longer to spool up than pistions which are instant.

be aware of you wind azimuth tables when hoovering. they are there for a reason.

as blender says dont stir the pot. there wont be any feel to the controls you will have to feel it in your bum!..smal moovements . they are a very pilot friendly machine, docile and as tough as nails!!

enjoy this superb piece of machinery guys.. i never get sick of stepping into one!!

[Grainger]

Great advice guys, and helped me to have a brilliant day out today. Kept the stick waggling to a minimum, and we did some autos and PFLs, and flew a whole approach and go-around with simulated hydraulic failure (minimal waggling really helped here). Hovering auto in particular much less of a drama than in the Robbo.

Was a bit too enthusiastic pulling in the power at the bottom of the first PFL - looks like you need to be really careful to avoid over-torqueing, so that's something I'll work on for next time.

The other thing I noticed was that the workload is still quite high getting used to the different environment / control layout, and that means the scan isn't up to the usual standards - once I get more used to it then hopefully I'll get back to flying the numbers.

Great experience and a fantastic day out. It's a bit like falling in love all over again.

All those of you flying tomorrow, have a great day !

[CyclicRick]

The 206 is a very docile machine to handle. Good advice to get the power in earlier than you normally would in a robbo and take things nice and slow (especially with the tail rotor as said) and it won't bite you. I always think that the 206 gives you lots of feedback as to how it's feeling (hot , heavy, high etc.) coaxing usually does the trick more than thrashing. A very reliable workhorse.
BUT.....give me an AS350 any day!

[Arm out the window]

Not too sure about the 'slow spool up' comment above; generally if you have the power available to do what you're proposing to do, it will be there pretty much straight away when you pull on the collective (some machines have lazy governors, but that's a different thing).
Getting the approach stablilised early is good, though, from the point of view that you will know early if you'll be using high power settings in an approach rather than getting a rude shock as you come to the hover above a pinnacle or whatever.
Racing down in auto and reefing on the collective at the last moment will certainly make for torque spikes and use of more power than you otherwise would have done.

[PPRUNE FAN#1]

Once you get comfortable enough with the machinery that you can flick the battery switch on without having to look up and search for it, you'll probably be pretty good at flying it. Others here have given great advice. I can only add two cents more.

CYCLIC FRICTION! Many pilots like to take the friction completely off in their 206's, which produces a very loose control that feels as if it's not connected to anything. Not good. If you watch such pilots in flight, their cyclics move too much. Maybe not all the time- but in general. Too loose is not good.

While there are those who claim to be able to keep the cyclic absolutely still under all conditions, I've flown with enough to know this is simply not true. Watch their right hand while they fly. You will see the cyclic jiggle and wiggle (with some pilots it never stops moving!). Remember this: Each time the cyclic moves, the swash plate moves. And more often than not, the swash plate does not need to be moving.

I use enough cyclic friction to creat a drag. Not so much that movement of the stick is inhibited, but enough to give me a "break-out force." The 206 responds really well to that "pressure, not actual movement" theory we were taught back in Primary. With absolutely no cyclic friction, it is almost impossible to apply pressure to the stick without actually moving it. I demonstrate this to disbelieving pilots by putting on a lot of friction in flight. On a relatively calm day, you can set up a very nice hover or even a rock-solid cruise and the cyclic never has to move. And they'll go, "Yeah, you're right, but I just like it better the other way." Eh- personal preferences.

On the other hand, too much friction makes for jerky control movements though, as you fight your way through the break-out force. Over the years (8,000 hours in 206's alone) I have experimented and have found that if I use enough friction to keep the cyclic from moving on it's own, that's just about right. For me. For you, I cannot say anything but please use *some* cyclic friction. It will make you a smoother pilot.

Here's another tidbit I learned a long time ago: Never pull the collective faster than the torquemeter needle can move. Allison 250's have pretty good response, but that gas generator huffs and puffs as it tries to match power to the demand, and there is a slight lag. If you experiment you will see that you can indeed pull faster than the needle. Not a good thing when making large collective movements up near your power limit. Don't do that.

And that's the thing about all turbines- you don't get much tactile feel between, oh, 80% torque and 120%. So you learn to keep both eyes outside of the cockpit but your third eye on that torque gauge. Eventually, you'll get to learn where your left arm is at 80% (or whatever your cruise torque value is), and that reference will help you greatly on takeoff and landing. Eighty percent is eight percent. So if you're doing something tricky and you're concentrating outside the aircraft and you suddenly realize that your left elbow is cocked a lot more than usual and your left leg is almost straight out, you might want to glance at that torquemeter.

One final thing. If there are just two of you onboard when you're hovering and you turn your tail into the wind, you will be in for a startling experience. The wind will get under that horizontal stabilizer and lift the tail like you wouldn't believe. You'll find yourself with the nose down, stick back in your gut, moving forward and thinking about that flimsy tin that the tail rotor driveshaft cover is made of while wondering if you'll actually feel it when the main rotor blade slices through the tail rotor driveshaft.

I love the 206. It is probably my all-time favorite aircraft.

[The Nr Fairy]

One thing I've picked up, having moved to 206s from R22/R44 - check the TOT gauge after a power increase !

[Darren999]

Hi All,

What great advice. I have just finished my conversion here in the US. What a great machine to fly!, different to my Bell 47!!. I found Auto's a dream, and a hovering auto a non event. Can't wait to do some more with it. Thanks all.

Darren

[Buitenzorg]

The 206 is a simple aircraft with all the bugs worked out of it. Treat it right and it will reward you with great reliability and very enjoyable flying. The only problem you’ll have is a reluctance to get back in a Robinson afterwards, no matter how much you liked them before! For your transition, remember it is just another helicopter, everything you learned so far still applies.

The most common way I’ve seen (and done) of getting torque and TOT spikes in the 206, is late and/or insufficient application of left pedal as collective is raised and/or airspeed decreases through ETL. Now the nose starts yawing right, the left foot goes in, and about two seconds later you may have a 15% torque spike. This is especially common if ETL is lost unexpectedly on approach, due to misjudging the wind and/or flying a fast approach. The ship starts sinking, collective is raised quickly, forgetting the pedals, oops the nose is going right, stand on the pedal… overtorque.

The way to avoid this is obviously to anticipate, much more so than in any RHC product. Get the left pedal in early, it’s easy to take it out if it was a bit too much, and you won’t have any problems. The same goes for the collective actually, start raising it early during deceleration on approach, and you’ll never have to “grab an armful of collective”.

If you’re hovering at high AUW, using high torque, and the nose slews right due to a gust, you have to get on the left pedal right away, or you might get into LTE (the 206 tail rotor is much less effective than those of the R22 and R44). But at the same time as you push the left pedal, GENTLY LOWER THE COLLECTIVE. This decreases the torque output of the engine, thereby also decreasing right-turning tendency your pedal input has to overcome. If the skids should touch the ground, well that’s what they’re for (obviously not if you’re moving sideways at any speed).

Hot starts are mainly due to three things: finger trouble, weak battery, dodgy fuel control. Avoid the finger trouble by ALWAYS, just before hitting the starter button, rolling the throttle full open, down to idle and then closed. Now you know it’s closed. Have your left hand on the throttle, press the idle stop down with your right index and the starter with your right middle finger (“two-fingered start”). Should TOT rise alarmingly, snap the throttle shut with your left hand, keep your right hand where it is for 10 secs. to motor the engine. Instant abort.

Learn to recognize a weak battery by how rapidly the igniter snaps and how quickly the engine pitch increases. Another good indication I’ve found is watching how much the fuel pressure drops as you hit the starter, if it drops to near zero the battery is weak. As your experience grows you’ll quickly be able to tell if the start is liable to become a “hung start” or will come out OK. When in doubt, get an APU or battery cart. If the aircraft doesn’t fly much, an older NiCad battery will get a lot worse in the interval between deep cycles, and even sitting for a day or so will cause it to lose charge.

With a good fuel control, there’ll be two minor but distinct TOT spikes during start: just above 20% N1 and just above 30% N1. With a worn-out fuel control, these spikes are often greater in magnitude, and may happen at different stages of the start. One of my “high-pucker-factor” starts in the 206 happened with a TOT spike at 55% N1! One thing I’ve observed and used to my advantage, is that while the Bendix fuel control is supposedly non-modulated, if you roll on the throttle just until it lights off and stop, the start will be cooler than if you go to idle right away. I’ve never been able to get an explanation for this, and many people don’t believe it, but my technique when working with a known marginal fuel control has been: roll on the throttle until the fuel pressure dips down, hold the throttle position, light off about 1 sec. later, hold the throttle position until after the second TOT spike at 30-35%, roll to idle. It seems to work for me.

If the throttle is very stiff to move, it’s most often due to a certain bearing in the linkage behind the collective (don’t know exactly which one, your engineer should be able to help you). Replacing this bearing is MUCH cheaper than a hot start.

PPRUNE FAN#1 is correct about the cyclic being moved around due to minor turbulence etc., however I’m tall enough that I can very comfortably rest my right knee against the door post. Thus, my hand really doesn’t move. If you’re so short that this won’t work for you, good for you, the cockpit will be much more comfortable than for me! And use some cyclic friction like PPF suggests, find which amount works best for you personally.

On your preflight, if you don’t see any spilled oil, you’re out of oil! This applies to engine as well as MGB. BUT, if you should see any oil leaking from any of the stainless steel oil lines on the engine, be sure and get an engineer to look at it. This oil goes to bearings which turn at close to 50,000 rpm, and they really need that oil…

Staying with the subject, some 206s have a sight glass on the engine oil tank. These are no more than ornaments. Always take the cap off and look into the tank. If you can see the seam of the tank, you can add one quart, so you won’t have to keep half-full cans of oil around. If on the other hand your engine oil tank is suddenly full to overflowing, the labyrinth seal between the overrunning clutch and the ancillary gearbox is probably blown, and oil from the MGB is transferring into the engine.

You’ll love the 206 like I did and still do! But if I can ever find the engineer responsible for the pilot seat I’ll strap him into an old one for 10 hours and we’ll have a chat about if he still thinks it such a good design then!

[Grainger]

Thakns guys - next flight in on Friday, plenty of things for me to think about and to try out.

Here's the next question - is there any truth to the rumour that you are not supposed / allowed to fly any other types during the type conversion ? I couldn't find anything about this in LASORS ?

[Mars]

Grainger:

That is only a JAR-OPS restriction contained in JAR-OPS 3.945(a)(8)Once an operator's conversion course has been commenced, a flight crew member does not undertake flying duties on another type until the course is completed or terminated [unless otherwise approved by the Authority (See IEM OPS 3.945(a)(8))]- it can be alleviated by the Authority under certain circumstances:[list=1] A conversion course is deemed to have started when the flying or STD has begun. The theoretical element of a conversion course may be undertaken ahead of the practical element.

Under certain circumstances a conversion course may have started and reached a stage where, for unforeseen reasons, it is not possible to complete it without a delay. In these circumstances the operator may apply to the Authority to allow the pilot to revert to the original type.

Before the resumption of the conversion course the operator should establish with the Authority how much of the conversion course needs to be re-covered before continuing with the remainder of the course.[/list=1]

[Grainger]

Thanks Mars - and if I understand correctly, JAR-OPS applies to Commercial Air Transportation, so as a PPL(H) doing a conversion, that restriction doesn't apply ?

[Mars]

Grainger:

That's correct.

[Grainger]

Mars: Thanks: that simplifies the next couple of weeks of my life considerably - the problem was that my R44 LPC is coming up at the end of the month, and I wanted to get a hour or two in so's to be current for that - plus I want to take a friend out, and I can't do that yet in the Jet Ranger.

Hmmm - juggling all these ratings is going to be fun :\ !

[Grainger]

Had a really useful session yesterday - worked on some of the things that I wanted to improve on from last time - particularly with getting a feel for power settings, improving the scan and so on. We did some limited power work - cushion creep takeoffs, normal and precision approaches, confined area, and some sloping ground work.

Thanks for all the advice so far - tried a few things out and gave me plenty to think about, especially getting the approach stabilised early and so having plenty of time to sort everything out. We tried a couple of different ways and got some good approaches without having to pull in bags of power at the bottom. Much better.

Stirring the cyclic didn't seem to be too much of a problem anyway, so didn't try any friction on there. Maybe each machine is a bit different, but it didn't seem to be necessary.

Worked hard but really enjoyed it and beginning to feel quite comfortable with the machine. I can see how you could easily fall in love with a Robinson but end up happily married to a JetRanger.

[tvpilot]

What are the requirements for a conversion from piston to Jet Ranger?.

Hours,Written Exams and Fligth Test ect.

[MD900 Explorer]

As my geordie friend has said, Kissmysquirrel is quite correct, in that it is a minimum of 5 hours on type, but if you are a slow learner it could take up to 20 hours. (However long it takes to grasp the scan and be safe eh!)

Then there is the multi guess Type paper and then a TRI examiner must assess your suitability for type by way of examination in a flight test.

Grainger , Good luck with your type rating

MD :ok:

[Tony Chambers]

hi fellow members,
i am looking for some help please. Does anyone know the going rate for the lease of a 206 in spain or does anyone know a contact of a brit company who can carry passengers and operate in spain on a pleasure site.
Thanks for any assistance.
:ok:

[leemind]

call Bill Lowry at Biggin Hill Helicopters 0870 443 0555. I know he was looking at the possibility of doing something in Spain.

[Dantruck]

Wet or dry lease, sir?

And check your PMs.

[Arm out the window]

Could anyone please enlighten me as to why the Long Ranger has a reduced Vne at power settings greater than 85% Tq?
Thanks.

[Ascend Charlie]

It is because you are pumping large amounts of power into the txmsn, and the rotor is tilted a long way forward to go fast. This makes the bending forces very high - the txmsn is trying to lean forward but is mostly restrained, the engine cannot move but its drive shaft is being bent by the tranny, and the mast is being bent forward by the rotor.

So, either reduce the forces by going slower with high power, or reduce the power if you want to go faster. Your machine will last much longer if you do so.

[belly tank]

ARM,

Just to back up what A.C said,

In the jetranger you have a VNE OF 80kts above 85% TQ, again for mast bending purposes.

cheers

BT

[Hilico]

As an asker of naive questions, may I present two.

Firstly, does this mean that if you're heavily loaded (at MTOW), it takes more torque to fly at a given airspeed, and so you're limited by that Vne?

And secondly, what torque setting do 206 jocks usually cruise at? And if it's not a torque setting, what is it? A constant N1? TGT?

[Arm out the window]

Thanks guys; I thought it might be something to do with getting towards forward cyclic range of movement limit, but what you say makes good sense.

Hilico, we usually set 85% Tq (max continous) and accept what airspeed we get, usually about 100 kt in the Jet Ranger and 110 in the Longie.

[Ascend Charlie]

Remember that your total reaction vector from your rotor disc has two components in forward flight :
The first is a vertical component, and is what holds you up in the sky.
The second is the horizontal component, which pulls you forward (or backward or whatever.)

When you are very heavy, most of the torque is used just to keep you up. Tilt it too far forward, and you will start to sink, so you will be limited on how fast you can go. Similarly, for the same torque figure, you will be going slower when you are heavy.

A Jet Banger in normal cruise is around 70-75% Tq to get around 100kt. To go faster, or if you are heavier, you will use more torque.

But it is unlikely that, once you are into the drag bucket above 30 kt, you will be pulling over 85% just to stay airborne. If that was the case, you would be pulling 200% just to hover.

85% cruise will move you quickly, but at the expense of fuel burn. Also watch your TOT limit.

[Treasure Hunt]

Largly depends what weight I have on board.

Typical cruise for me would be at about 75% with no pax and max fuel.

Saves in the long run:ok:

[Floppy Link]

Folks
I'm just about to renew my 206 LPC to keep my ATPL(H) current despit selling my soul to fixed wing.
This thread is great stuff. Keep it coming!
Russell

:cool:

[Grainger]

Well, my next flight is booked for tomorrow. . .

Anyone got any tips for underwater flying :( ?

[GLSNightPilot]

Back when I was flying the 206, our company limited it to 80% TQ max continuous, and that's what we usually flew at. We just pulled 80% TQ and accepted whatever airspeed we got. 80 kts isn't close to the maximum airspeed you can get if you pull the torque up into the yellow, it's just the maximum allowed to prevent excessive mast bending. You pull whatever torque it takes to take off (almost always > 90%, very often 99% in the GOM at max weight), then reduce to 80% as your airspeed increases and fly away. If you keep the torque up, you'll exceed 80 kts fairly quickly.

[evod]

As a rule of thumb i use 80% Tq to cruise in the cooler months and 20degs C less than max cont tot in the warmer months (if temp limited). Some employers want you to sit on 85% and/or 738 deg when in the cruise to minimise time ($) but treat it as you would like to be treated. A couple of degrees or % of torque make a big difference.

;)

[that chinese fella]

Interesting.......

I had been taught that this limit was due to Main Rotor blade stresses ie. big changes in AofA with resultant big movement of Centre of Pressure and associated loads / stress.

Any thoughts?

TCF

[pohm1]

Isn't it also to do with retreating blade stall? (A high angle of attack and a high forward speed.)

[Ascend Charlie]

Retreating blade stall at 85 knots???

Bong! Wrong!

A 206 has a Vne of 128 Kt or so, and it can't be certified to that speed if it is going to stall before that.

The limit is due to bending forces in the mast, transmission and driveline.

(Gunship Hueys in SVN would get blade stall on attack runs - although this might have been associated with the high speed of the dive, being grossly overweight with rockets and bullets and armour plating, and the vigorous manoeuvering to get out of the hot zone after release of ordnance.):sad:

[Grainger]

Finally got a break in the weather today. What a week !

Did some upper air work, vortex rings, autos and a couple of interesting confined areas / pinnacle. I'm starting to get a feel now for the power settings; you can pretty much hear the note of the turbine - so spending more time looking outside and less fixated on the torque gauge. Autos were good too - getting the RPM control sorted out and a good power recovery at the bottom. Overshot the first field though - it just keeps going compared to the R22 / 44 !

Want to have a go at the written exam next week - does anyone know how I can get hold of a syllabus or example questions - or is it just a case of mugging up on the POH ?

[tagg]

Small point but it doesn`t have to be a TRI examiner(TRE), just a FE will do. The TRI doesn`t apply to the 206. All you need to instruct on the 206 is a FI and the rating on type.

Don`t know if they(CAA) have filled the loop hole but at the minute you don`t even need 15 hours on type prior to you instructing on it. A mistake in the amendments to JAR FCL.

[Arm out the window]

Being a relative newcomer to the B206, I found out a new feature of the type today that was most impressive.
I was shut down for a couple of hours in the sun on a guano-covered pontoon, nowhere to rack out except in the cabin - too hot, nowhere near enough shade to cover me.
Then I had a eureka moment - hopped into the baggage compartment (with extender). Head towards the tail rotor, knees up on the bulkhead, door open, gentle breeze wafting in, waves gently rocking - not exactly the Hilton, but pretty relaxing nonetheless.
So to all you 6 footers, bad luck! I guess there aren't too many advantages to being a shortarse, but this is one.

[B Sousa]

Good Idea. I always found that going into the Air Conditioned Pilots Lounge and grabbing a nap was easier. You guys are a bit different...........
And yes, you mount the Camel and ride it to town, not just mount the Camel.

[whatsarunway]

You should try that in the ec120!
there is enough room in that for a little female company plus it doesnt smell like a jetranger!

how come all jetrangers smell the same?

[Grainger]

At 6ft 4 I don't think I'm going to give that one a try !

There seem to be quite a few drips and drops in there so you'd come out ponging of a nice mixture of oil and Jet A1.

Oh, and around here if you leave the door open the rain gets in so you'd probably get pneumonia.

Nope, it's the crew room and a nice cup of tea for me.

[sprocket]

The Bell 47 always had the 'shade of the blade" to retire under.

Stretching out was never a problem.

[John Eacott]

AOTW,

The cushions off the rear seat back, under the belly/tail boom, suits those of normal vertical genes ;) Probably a bit more airflow if you're shut down into wind, methinks?

Mind you, in 2.5 metres of snow atm, not a problem that we're currently facing, although we did take one of your Cairns based hosties for a flight yesterday :cool: Just to change the subject.....


:p

[Arm out the window]

John, Sprocket, the under the machine option is usually a good one; unfortunately in this instance there is a bit too much 'aroma de seagull' to want to get down amongst it!

B Sousa, I was always told that it's good to get in early when choosing a camel; you don't want to get stuck with an ugly one.

[Gomer Pylot]

Back in the old days, I used to carry a hammock with me. Just nylon netting, with a ring at each end and nylon rope attached to them. Attach one rope to the tail stinger, the other to the aft tiedown shackle, and you're ready to go. Shade can be a problem, of course. I far prefer the back seats to the baggage compartment - at least you can open the windows and doors, and put a shade in the window with the sun coming in. The seat backs on the deck are the best, of course, but I too have been on platforms with the seagull residue a couple of inches thick, and I don't even get out on those.

I landed on one of those roost platforms once, and it had been raining for awhile, so the mess was slippery and wet. I told the pax that if they slipped and fell, to just call for a boat, because they weren't getting back in my helicopter covered in that stuff. It was bad enough with the floor covered from their feet, but I wasn't taking a chance with the seats. :yuk:

[belly tank]

Just received the STC and flight manual suppliment for our B206 to allow internal gross weight to be increaded to 1519kg or 3350lbs....there is no requirement for helicopter with SN 2212 and subsequent with the 65" tail rotor. There is a VNE of 78kts above 1451kg, and practice autos above 1451kg are prohibited.

Aircraft before this SN have to follow BHT-206-SI-129 SB in accordance also with information letter 206-04-89.

Involves placards and cross check of serial numbers on skids to comply with increased weights.

[Ascend Charlie]

Be interesting to see how the wear on the blade grips progresses.

In a former life, we would take off every flight at 3200 lb, and the brinelling on the grips was horrendous.

If you've got all that weight inside, it is probably fat passengers, and they might not be impressed at travelling at less than 80 kt? A sling load doesn't care, and usually can't go that fast anyway. But the people paying by the minute could complain, maybe? At least they would be airborne, though, instead of waiting for the next chopper to join their chubby mates...

[Arm out the window]

That's going to make things a bit easier with 4 fat tourists.

[SASless]

It helps us fat pilots too! Finally, Vne matches Vmrc !!!:ok:

[Giovanni Cento Nove]

AC, the brinelling was caused by the low speeds and pitch setting you guys used to use. It doesn't effect ships used in constant slinging i.e. fire bucket work and the same yoke is used on an 206L4 which can be 1200 lbs heavier after all. As the blade rotates and changes it's pitch setting it does so in a small area at slow speeds. At higher collective and cyclic offset from neutral i.e. cruise the variation in pitch is over a larger area of the yoke. The same applies to the trunnion with larger flapping angles. Then again WTFWIK.

[Ascend Charlie]

Giovanni:

Yeah, yer probably right.

Most of the ops were just drifting around waiting for something to happen, 60-80kt, with the occasional dash when the adrenalin pumped.

The raised weight limit still doesn't mean that the engine power and tail rotor authority are going to do any better, though.... :{

[belly tank]

AC

Reading the suppliment last night it stated that for hover ops at gross weight above 3200lb, IGE manouvers refer to basic flight manual.

While OGE manouvers are only to be performed in calm wind.

[Squirrel]

I know the 206 has great auto capabilities, but there is a real difference between autos with two people on board and 60 gals vs. MGW. Not allowing practice autos above 3200 appears to tell you something. I understood one of reasons for the higher external load limit was the ability to jettison the external load to enable a successful auto. If that was one of the reasons, I wonder what changed since to make it safe & successful to now auto with 3350.

I would be interested to hear more details on these issues from Bell or someone who has the answers or corrections to my assumptions.

I would personally favour a 206L, 407, Astar or such instead of pushing the envelope - less stress = better health.

[CAMSHAN]

Can anyone please help with the pitch and roll limitations of the BH06, either Jet Ranger, or Long Ranger on a ships deck.

[pilotwolf]

You might have more luck in the Rotorheads forum or try emailing Trinty House in the UK! :}

PW

[Grainger]

Yee-haa ! Passed my flight test a couple of weeks ago and got my new ratings pages back from the CAA today.

Thanks everybody for the advice and encouragement !

[CRAN]

Congratulations Grainger!

Now get out there and enjoy it!

CRAN
:ok: :ok: :ok: :ok: :ok: :ok: :ok:

[Whirlygig]

Looks like a celebration on Saturday?

Well done

Whirlygig

[imabell]

never have the cyclic friction on:ok:

[Darren999]

Hi all,

Have really enjoyed reading this thread. I have just completed 20 hrs on the 206, what a joy!! I enjoy my Bell 47 but this was just tons of fun!. I was very lucky to have gone over hovering auto's, stuck pedals, 180 auto's, max perform take off's, slopes, confined landings, pinnicals. I still however am very nervous on start up, the dreaded hot start!! hopefully this will ease with expirence, and following advice on here.

I have really learnt a lot from this thead. One thing I did read was in reference to the hovering Auto, that you must be at 70% and very close to the grd. We were performing these, from various heights up to 10 feet, and whilst going sideways, and in turns, the auto in all situations seemed very benine. The 5 hr conversion cost me $3500, which I thought very reasonable. Keep the advice coming..

Darren:ok: :ok:

[paco]

With reference to power, if you come in on a controlled approach at around 250 fpm, you shouldn't have to move the collective at all at the bottom, if you get ground effect from the surface - particularly useful in mountains

Enjoy the machine, it's a goodie.

Phil

[gizmocat]

Hi All,

Quick question, What
indications on the panel appart from the Tq gauge, would a 206 pilot get if he was overtorquing the engine. For instance,
the checklist gives a max Tq of 100% for 5 mins, or
110% for 5 seconds. Would the pilot see a rise in TOT
or transmission temps, or would the bugger just seize
or what?

TIA
MB

[the coyote]

From memory in the Jetranger, 100 Tq = 317 SHP from the engine, which is only about 75% of the C20B's rated max power of I think 420 SHP.

Tq then is obviously a drive train limit of some sort, so you will not be overtorquing the engine but rather the drive train.

No other cockpit indications for overtorque other than the guage.

Ask an engineer what inspections/maintenance is required for an overtorque, and you will get an idea of what damage it does!

[The Rotordog]

The coyote is right, there is nothing, nada, zip...no indication at all that you're pulling 120%. You could do it all day long. Might not even damage anything unless you're in an OGE hover in a strong right crosswind (but the inspections will have to be done regardless). If a C-20B is installed, you might not even overtemp the engine at lower altitudes. That's the thing about 206's that new pilots must be aware of.

[paco]

Use your ears when you've got your head out of the door! The gearbox akes a distinctive whine when it gets near the limits

phil

[gizmocat]

Thanks for the swift responses chaps, lots of usefull info.

Bests
MB

[Helinut]

They aren't standard, but there are various retrofits that effectively record or indicate an exceedance. I have seen some that indicate in both the Tq or T4 gauge. (Overtemp indicators are more common, in my experience). Others simply record the exceedance with its details for later download from a black box in the baggage bay.

[407 Driver]

From my distant past as a maintenance person.... Some of the areas to look at to see signs of torque ( not guaranteed indicators ) are:

RH side aft fuselage panels behind the fuel-filler cap...if the panels are all wrinkled or "oil-canned", chances are that the airframe may have seen some "torque" in it's past, or simply old age ?

Transmission upper split line, ...if the pro-seal shows some hair-lined- angled cracks and if there seems to have been a touch of movement in that joint...chances are it may have moved a mm or two under load.

Look over the mast, re paint chips, etc, The mast is actually "micrometered" for distortion in an overtorque inspection.


Generally, nothing is found during an over-torque inspection, but that's no reason to be pulling that much power. The 110 for 5 limitation should get you out of a nasty situstion, so perhaps LEARN to avoid that situation after the aircraft saves you once !

I've been to 120% spike once, (9,400 on type) and the inspections revealed nothing, the components all made full time.

[SASless]

Over-torquing can be done oh so easily with the 206 as well....when operating near the edge....one wee slight tug on the collective or a bit of boot on the pedal and you have done it.

Paco....how you know the tranny whines when you get near the max? Hangar talk?

[The Nr Fairy]

I feel slightly ashamed - 407 Driver, can you point me exactly at the "Transmission upper split line . . . the pro-seal" - I think you mean the drive shaft forwards to the gearbox, but I'm not sure. Shouldn't I know that ?

[sprocket]

Nr Fairy: The transmission/G-box has an upper and lower (main) case. I think 407 Driver means the joining splitline between the two when assembled.
The upper case houses the outer ring gear from which the planetary gears drive against. The torque is transferred from the upper case to the lower case and mounts, through this joint.
High torque can cause movement/twist at this joint. The proseal is a rubberized sealant used to seal the join externally and is visible. Any movement can cause the paint to crack at the join.

[B Sousa]

Since your talking about Overtorque. Keep your eyes on those Tele-Temp strips. I have seen a few get burnt on aircraft that were at least not reported to be overtorqued, but Im sure were. They are a cheap indicator for problems. Also another sign would be some slinging of grease from the Main Drive Shaft when the seals go..This does not occur all the time. Time to say something to someone before things get messy.... :ugh: :yuk:
Nr Fairy. If you need some schematics I can probably help you out via attachments or FAX..

[S92mech]

I worked in the forestry spaying business with 206Bs for several years. It was common practice to fly 200 to 500 pounds over gross and pilots didn't look at the torque indicator very closely. As said above signs will start showing like the oil canning, but what gets expensive is the 1500 hour inpection on the main gearbox. The sun gear and the ring gear will be worn beyond limits long before they should.

[407 Driver]

Thanks for the quick and accurate response Sprocket.

I've looked in at the transmission of some old 206's in my past and seen obvious paint cracks on that upper joint. You know what thas happened to the ship in the past.....

[NickLappos]

gizmocat,

There is a basic misunderstanding in your question that should be discussed, and that is the idea that a published limit is associated with a failure. In other words, "If I overtorque by 1%, what will break that I can look at to be sure the aircraft was not overtorqued?"

The simple answer is nothing will break, because most helicopter limits are not at the edge of failure for the stressed items. The torque limits are set by a judgement that so many cycles at that power level, and so many at proportionately less will result in gradual breakdown, chips and possible gear tooth cracks. The issue is fatigue life, not one-off failure.

When you are pulling the excess torque, the engine power indicators will all tell you that you are high in power. If you pull, say 120% when 110 was the limit, you can expect nothing bad to present itself, yet. If the box has this happen every flight, over a relatively short time, chips might form, or the gears might develope small cracks at their roots. Keep it up, and a tooth will fail, or perhaps worse.

When we test and qualify, we are making a statistical bet that the worst case field usage will conform to our power levels, and that the gearbox quality will conform to the worst case assumptions we have, so that for the prescribed overhaul interval, the box will be reliable and trouble free. Pull more power regularly, or abuse the box in other ways (wrong oil or long change intervals, improper warm-up, excessive number of cycles, excessive rotor vibration, water/corrosion buildup, etc) and it will not last as long.

In short, most common overtorques result in reliability problems, and you trust the pilots who came before you to properly fly and write-up the helicopter.

[gizmocat]

Thanks again for the answers. I'd better explain the main reason for my original post. A mate of mine is working to design a part task trainer, and the "out of cockpit" indications are impractical to simulate on a computer (paint chips etc). We were wondering if we could somehow penalise the pilot for being in an overtorque situation for too long... Stop the donk, flash a warning light, that sort of thing, but keep it realistic at the same time. Maybe we'll just have to up the anti, and blow the gearbox after a certain ammount of time in an overtorque situation. Should keep them on their toes anyway.

Bests
MB

[offshoreigor]

Hi Gizmo

As I recall from days gone past, you have to really hit the high end in a 206 to do damage.

I once took off from a cut line in North-Central Ontario during a Snow sqall near dusk and, you guessed it, everything went dark pretty fast! On top of that the instrument lights were U/S. When I got the flashlight on the panel (thanks to a quick thinking passenger) I saw the Q coming down through 112%!

The engineers later said it would have to be near 125% to do any real damage but they inspected the mast anyway. No problems.

The one other thing you can check is the "through shaft" under the engine. If you are not able to move it fore and aft, you have most likely done damage, ie. "BENT SOMETHING"!

Cheers and Merry Christmas

:ok: OffshoreIgor :ok:

[paco]

Another couple of places to look are the pan underneath the engine and the rear of the fuselage just before it hits the tailboom (thanks to the boys at Yellowhead for those). I would guess that the even spacing between the tailboom and fuselage would be affected as well.

Sasless - no not hangar talk - experience! We were trained to listen to the ol' 47's engine instead of looking at the RPM gauge, and when I flew a longranger without a torquemeter on the side I did the same with the sound of the tranny (best with your head out of the door). It's a very distinctive sound at 100%, even more so above that.

Phil

[yoobeedo]

Any links for a Bell 206 Flight Manual or Pilot Training Manual online.

:}

[paco]

Phil
Your link is no longer current - I've deleted it to save people wasting time.

I don't think Lear Siegler has had the Fort Rucker 206 (TH-67) Tech Manual on its website for a long time.

If you find a direct link to an online manual, please post.

Heliport

[Sikorsky]

Try this link:
Navy Gouge (http://www.navygouge.com/helos.html)

[yoobeedo]

Thanks for the info so far. Anyone with a civilian version, prefer 206b3

[Choppersquad]

hi all
can any owner 206 operators tell me the hourly cost of a 206 111 based on approx 175 hours per year usage.
if possible has anyone also looked at the operating cost of
a r44 raven 2 based on its life span taking into consideration
its overhaul at end of life.
Some pilots will tell you are better buying a old jet ranger and paying for componants as they come up,the age of the machine will insure you are at its lowest cost when purchasing the machine insuring you do not loose as much when selling it versus r44 for half what you paid for a new one.
hopfully some one has operated both to settle the mind on the matter.


regards
choppersquad

[Cross-eyed]

If your willing to pay for an excellent model that will answer your question and more both Conklin de Decker (includes helicopter cost database) and SLM (in my opinion, has a better model) offer solutions. Both consider residual value.

Conklin is at: http://www.conklindd.com/cgi-bin/softcart.exe/store/lcc.html?L+scstore+rkpf4610ff7dd87d+1107062294

SLM is at: http://www.aircraftcostanalysis.com/

I have used both but have not stake in either so I hope I'm not breaking any forum rules.

[Choppersquad]

thanks cross-eyed i will look into this,but there must
be a 206 owner on the forum who can give me
a idea .as we all know when turbines go wrong
it hurts the pocket.some one must have gone from a
turbine to a piston machine due to operating costs
who can settle this dicussion.

regards

cs

[Aesir]

I operate B206B and I find that the Bell published Direct operating cost is pretty accurate @ $200.- pr/hr.

The DOC does not include insurance, hangar, crew compensation & financing.

But the R44 is probably cheaper although I have not much experience with the R44 (only R22!) but comparing these two is comparing apples and oranges, they´re not really in the same class if you want to operate them commercially in my opinion.

Its like people often compare the B206B with the AS-350B2 which really competes with the B407.

I guess the B206B should be compared to EC120 really! and I know that the JetRanger will be cheaper and more reliable than the EC120 although the JetRanger will make more noise.

But for a cheap to run personal helicopter I´m sure the R-44 is fine.

[paco]

I know about 10 years ago, it was approx 80,000 pounds per year to run a 206 privately, meaning roughly 250 hours a year - if it was 60,000 one year, it would be 100,000 the next, so the figures were quite accurate.

We operate here on around 200 per hour, but our machines do 600 hours per year on commercial basis.

Phil

[helicopter-redeye]

I did the comparison a while ago for by business plan, so I'll post it when I can find in in the next day or so, - 206 -v- R44 (NB, the R44 won)

h-r

[206 jock]

If you want to keep your machine for your own use and don't need the 5th seat, I'd say the R44 R1 is the machine for you. I'd recommend that you ignore anyone's view on DOC on a 206: the reality is so tied to component times and - frankly - luck, that what the papers say and what you find in reality will be different.

I bought a 206, primarily as I wanted to lease it back to a commercial operator to contribute to operating costs (and keep the VAT-man off my back!). But frankly it's cost me a fortune in the last three years with unexpected repairs and components due. But I've had a good run for the last few year (touch wood), but with a turbine wheel due in a few months, who knows what horrors will come to light when they take it out!

But no doubt, the R44 will depreciate, where the 206 will hold its value - but be warned that the value of a 206 is more closely asscociated with component time than age.

Personally, I love the 206 to fly - it is better than the R44, but whether it's worth the difference is open to debate.

[Aesir]

I guess I have been lucky with the B206 I' ve flown or operated, but unscheduled maintenance has been pretty much non-existent, except for the *:mad: :* Janitrol heater, although right now, "Knock on wood" it works fine.

However "Choppersquad" you asked for operating cost based on 175 hr/yr. Those cost depend alot on the insurance, hangar cost, crew etc.. just figure around 200 USD pr/hr, or if you are in the UK on 200 Sterling, to be on the safe side and if you have unscheduled maintenance its just your bad luck, its really impossible to estimate the unscheduled maintenance required!

You dont really say if the aircraft is for commercial use or private? If for private then you cant go wrong with a Robinson, but commercially then:

http://valfell.4t.com/images/flysmart_logo_jpg.jpg

[Choppersquad]

thanks guys
helicopter/red eye it would be great if you posted the info
on the costs 206/r44 if you find same.

cs

[ground effect]

Have been looking around on line for some bedtime reading. Can anyone out there point me towards an online source for PDF files of the flight manuals for the bell 206??

[Haggis Hunter]

i've been doing the same and haven't come accross anything, i'm just looking for the JetBanger manual. if anyone one could point us in the right direction it would be much appreciated.

HH :cool:

[widgeon]

http://www.eflightmanuals.com/detail/itemList.asp?CategoryGroupID=57

this may give you a clue as to why they will be hard to find on the internet.

I think also that most manufacturers will only sell to the registered owner of the aircraft .

You may find some miltary ones look for TH57 and OH58D.

http://www.eflightmanuals.com/detail/itemList.asp?page=3&CategoryGroupID=11

You may need a US mailng address though , some interesting older ones though.

[Flight Safety]

While eflightmanuals is a good source of CD and paper copies of manuals, this website is a good source of original manuals, for the collectors among us.

Essco Aircraft flight manuals (http://www.esscoaircraft.com/level.itml/icOid/2)

[CareBear]

Ground Effect

Check your PM

Cheers

[ground effect]

thanks care bear have sent info to your PMs

[SiClick]

Ground effect et all
Care Bare has probably sorted you out, but if you still need 206 stuff PM me
Keep smiling:D

[Aesir]

Somebody out there who can verify that I remember correctly the transmission limits on 206B.

The 85% torque limit is a 317 hp limit! Right?

and the 85-100% Q limit is 350 hp limit! Right?

I dont have my manuals accessible at the moment! Would appreciate feedback from someone who can verify:O

[Ascend Charlie]

Who cares??

Where is your Horsepower gauge in the aircraft?

You only have a torquemeter. So, max cont is 85% torque, forget about the horsepower. Numbers like that occupy far too many brain cells, and they are the ones that die off early in your beer-swilling life.

Usually the only people who would remember something like this are the pedantic instructors who have heads full of such crap and trivia.

[OEI and Still Flying]

While Ascend Charlie might have a point , I dont know of any 206 jockey that would know these figures, here you are:::

This is for the 206B III engine is the 250-C20J

Max Continuous Power (SHP) 85% Tq = 270HP
Take-Off Power (Rated ) 100% Tq=317Hp


The above engine is a 420 shp detrated to 317 in the 206

Enjoy

PS Still beats me what you want the figures for!

[Aesir]

Ok thanks guy´s, don´t know how I got that 350 hp idea in my head.

No, the reason really is just to explain to others that the engine is derated (well or actually power limited due to gearbox) and its easier to explain using the horsepower figures.

I for example have a 206B with the C20 engine, which is 400 hp and since I usually fly at lower altitudes in cold climate it really makes no difference for me to have the C20B engine or the straight C20. Can´t use the horsepower anyway.

Thanks again.

[Lama Bear]

317 hp was the rating of the original C-18 engine. Bell never changed the max hp on the transmission.

[autosync]

What OEI and Still Flying said about the 206B III sounds familiar, i'll go with what he says, I thunk!

[SASless]

I saw this post on a US based website where some EMS pilots are discussing how to maximize the available power on Jetranger EMS helicopters. Some rather interesting suggestions were made by pseudo experts and they were interesting to read. The post immediately before the one I am going to paste here, suggested beeping up the Nr as being the right answer. This is the reply......what do you guys think?

The stolen post.....
Subject: Re: Increased N2 does not equate to less TQ available.

Be patient please, this is a long answer. If I have this wrong, I am sure it will be corrected post haste.

The INC/DCR switch changes the linear actuator setting which is in the throttle linkage to the governor. This sets the engines N2 speed which, when coupled via sprag clutch, sets a matching Nr speed.

You are enabling the fuel control to deliver more fuel to the engine and using up the engine horsepower available in excess of what can be applied to the xmsn/drive train. This is why helicopters have turbine engines spec'd with more horsepower than the xmsn/drive train can handle so their operating capabilities remain constant over a wider range of DA.

Torque is a measure of the engine power being applied to the xmsn/drive train. So long as environmental conditions allow the engine to produce more horsepower than is allowed to be applied to the xmsn/drive train, you can maintain a high N2/Nr without using up TQ. 100% TQ always equals the same amount of HP in the given aircraft. The engine may be using more fuel, more TOT, and more N1 speed (cooling/cumbustion air) to produce a given HP; however, the TQ/HP relationship is the same.

When you increase Nr speed, you gain more lift from the rotor system at any given collective pitch setting.

:confused:

[Flingwing207]

When you increase Nr speed, you gain more lift from the rotor system at any given collective pitch setting. I get this part anyway - the rest??

How about as RPM goes up, torque goes down if power remains constant, or put another way, if RPM goes up and torque remains constant, power goes up?

So RPM goes up, you get more lift for the same drag and more power for the same torque. Now about that "using up the engine horsepower available in excess of what can be applied to the xmsn/drive train"...

[Bomber ARIS]

SASless, appologies for a little thread creep here, but the more alarming thing to me was the accepted practice of hanging around in a 206, with marginal performance, in a 150' OGE hover with the patient on board, trying to pull out of a hover hole . Just add night, inexperience, fatigue and bad weather and perhaps the appaling US EMS accident rate is little more understandable1. always into the wind
2. vertical ascent until well clear of obstacles; usually 50' to 150'
3. smooth collective pull to 91-95%TQ; TQ spikes will occur with left pedal input, wind changes, etc., holding at 95% leaves some room without having an overtorque
4. the 206L will climb and then stop, be patient and gently work your way up 10' to 20' at a time by:
a. waiting for more wind
b. aft cyclic inputs
c. right pedal inputs + collective increases
d. be patient
e. be patient
f. be patient
5. once clear of obstacles, forward cyclic while holding 91-95%TQ until at 60KIAS and 300'AGL, then proceed on course

Where are the safety margins??

[SawThe Light]

We the pilots are the ones responsible for the safety of our pax and our selves. We are the ones that decide to pull pitch. We are the ones who decide that we can just sneak over that. We are the ones that think that we should just about get through there. We are the ones that decide that we should just about make it across to there. We are the ones that decide that it isn't really that bad. We are also the ones most responsible for accident reports.

If we are dicking about milking the extra ounce of Tq or the extra 0.25% of NR, we simply do not have the aircraft to do the job. As long as we continue to do it, we will keep the accident reports coming.

It is a matter of self-discipline but as long as we/you continue to do it, there will be little improvement in safety. Because we arrived, doesn't mean we arrived safely.

Sorry for the rant but there are very few helicopters that got to the accident site on their own.

STL

[Gibbo]

SawTheLight, yeah, we know that mate?

A jetranger is a jetranger; it does a job. Are you going to change A/C mid-task? The bounds are going to be pushed when you fly the weak and inspid girl, but, what are the rules of thumb, not the airmanship rules? They have been expored ; let's share.

Gibbo

[SASless]

Bomber,

That is the post that made me smile...I have heard and seen the same situation with 212's on Mud Rigs surrounded by trees. That would be a profile that 212man knows well but is not checked during Base Checks during the HayDay of the 212's in Nigeria.

Be it the GOM or other places in the oil patch....we always seem to have more load than lift.

[tottigol]

This post will be out of sequence and somewhat extended, anyway, the EMS industry in the USA is based on very different principles compared to the European and maybe Australian one.
At some point in the food chain someone HAS to see some profit to make the whole process work.
Consequently, somewhere expenses have to be cut; I am assuming that not all of the posters here are USA based, so let me explain that there are two main models of HEMS operations in the USA: Hospital Based and "Community" Based, whereas the former is a traditional vendor/customer contract and the second one really just makes money by charging the transported patients.
It's very common for most of the "Community Based" operators to limit their helicopter choice to the most simple and inexpensive 206L I/III model and these are often a ragtag fleet of tired "ex-Gulf' machines with some of them having in excess of 20,000 hrs in the book.
Given the generally more "generous" physical constitution of the American public, you can easily see how the venerable and often tired Longranger may be hard pressed to complete a climb to level flight from a confined area.
We will also see that most often than not, the pilots of this group have less flying experience as they are not required to fly IFR and exhibit a tendency to push a flight through even in marginal VFR conditions often leading to IIMC flight.
Combine that with the requirement to pull a flight through to see the money and there you have a perfect recipe for disaster.
Confusingly enough though, the first two accidents of the year (both fatals to an extent) involved very experienced flight crews in modern machines emplyed by the largest EMS operator in the US, none of which had a patient onboard since the transport had already taken place.
The common denominator here being night conditions.
By the way, it's my experience that by (beeper) increasing N2/Nr, indicated TQ increases as well due to an increase in total drag (flying a 412 that can be quite noticeable).

[Shawn Coyle]

Most of what was said in the original post is difficult to follow, it must be said.
Power is torque times rotor RPM (with a constant thrown in to do the coversions).
Torque is the drag on the rotor blades.
It follows that normally (and I must stress normally), that at a constant power, increasing the rotor RPM will decrease the torque.
In my short time flying the 412, I've been quite surprised to see that when we beep back the RPM for cruise, the torque goes down at a constant collective pitch - this is quite contrary to 'normal', and indicates that the rotor is more efficient at this lower RPM.

[The Rotordog]

Seems to me, if I recall correctly from my days flying the S-58T, 100%Q @100% RRPM would cause the engines to put out 1625 h.p. while 100%Q @93% RRPM would produce 1525 h.p. So that extra 7% RRPM gave us an extra 100 h.p.

But like a lot of things that I *think* are stored away in the memory, it may be incorrect.

[Aesir]

In the S-300C it is quite obvious that you can lift out of a tight spot by increasing the ERPM to 3200 instead of 3100 ERPM with same or less M.P.

If the Limit M.P. for the day is say 23" you can lift more by increasing the ERPM momentarily during take off to 3200 and still be within the 190 hp power limit. Are the above posts saying that I'm actally not pulling 190 hp @ 3100Erpm and 23" (MPL for the situation) but rather less HP and first when I reach 3200Erpm and 23" (absolute limit) then I'm pullin the whole 190 HP from the engine?

If I increase Rrpm by 10% I thought I would get 20% more lift out of it. Right? But is this 20% more lift then costing 10 or 20% more horsepower to make?

Also me experience is that by beeping up the NR to just above the 100% (manufactures often allow 101-2% NR) then I can easily lift a load I was unable to lift before at a lower NR setting.

Maybe theoretically you are using more horsepower but you are not busting any limits and still getting the job done!

[SASless]

Shawn,

After beeping the old girl down and seeing the Q drop off a bit...do you then raise the collective back to your orginal Q setting for cruise? One must remember to decrease collective prior to beeping it back up....or you might find yourself over torquing as I recall.

[rotorrookie]

Pitching over the optimum angle or best Lift/Drag Angle only gives you more induced drag(porportionally) Also Lift is velocity square so increasig the rpm at optimum blade angle should give you more Lift I think.....:bored:

[Flingwing207]

In my short time flying the 412, I've been quite surprised to see that when we beep back the RPM for cruise, the torque goes down at a constant collective pitch - this is quite contrary to 'normal', and indicates that the rotor is more efficient at this lower RPM.Would this be related to the airspeed of the advancing blade tip? I know that even in our little Schweizers, if we cruise at mid-green instead of top o'green, we use less fuel.

However, at the hover I suspect that the lift/drag and RPM/torque factors work as advertised.

[Rotorbee]

If I remeber right, we had that dicussion a few month ago and somebody -probably Nick- explained that with a slight lower rpm the there would be less torque because the higher drag (square) at higher RPM would result in more torque or something like that. I can not find that thread but it was a heated discussion.
Otherwise I have to talk to my shrink again, the halluzinations are back.

[helmet fire]

Shawn has said it right, though I think the answer is a little misleading in this situation, though it is very difficult to determine exactly what the original poster was trying to say.

Torque will increase with an increase in RRPM. But, if power is held constant (N1, TOT) then TQ must decrease witn NR increase. As usual with helicopters, this rule can vary too, dependant upon blade stall alpha, etc.

Beeping up does not always advantage your operation for several reasons, not the least of which is there are no free lunches. The most important consideration is the lift/drag ratio, ie when you get the most lift for the least drag (in otherwords, TQ) Most manufacturers have an operating RRPM slightly above the optimum lift drag ratio, so that a slight loss of RRPM will actually be benefitial to the aircraft, not further degrade your ability to cope with whatever is causing the RRPM loss.

Excluding tailrotor, there are two power limits to be considered in a limited power situation (what the yanks sometimes call max performance take off). Firstly, and most commonly is transmission limited (ie TQ limited) where the engine will produce more tq than the Xmsn can handle. In this situation, you will be weighing up and increase in RRPM giving you more lift at a lower tq versus the requirement for more power due to the degraded lift drag ratio. This is only going to be of minimal benefit, and you will reach power limits earlier with the higher RRPM.

Power limited situations (as opposed to tq limited) are those where the engine reaches a power limit such as temp, N1 or even fuel flow before the Xmsn reaches it's limit. In the UH1 for example, N1 limiting is common, and the result will be (in this case) RRPM bleed. In the short and long ranger it is more likely that you will get N1 overspeed whist RRPM stays 100% and you think you are sweet with the tq limit. When the UH1 bleeds, the rotor becomes more efficient initially (in terms of lift/drag) before tapering off. Thus when you get into RRPM bleed, you will get a slight improvement to help you get out of jail - but push things too far, and you pay big time.

So perhaps the 206 guy is giving a useful hint, but my feeling is that it's applicability is very narrow, and without understanding those applicability limitations, you are setting yourself up for grief.

As for who/what/where should HEMS be done, that is simply a matter for an appropriate risk management application. 206s have been flown safely on HEMS for decades, and should continue to do so, but perhaps it is about time that we apply risk management now we understand it, and limit the types, weights, wx, and especially visibility and light levels, etc that you dispatch a 206 into?

[SASless]

I posted the latest AEL EMS Jetranger crash preliminary report in the "Third US EMS Crash" thread. It speaks to some of the things being discussed here.

[Shawn Coyle]

SASless - yes we then increase the collective to get more power, and on descent before landing, since we're already decreasing torque before we beep up, there is no danger of overtorquing.

For the jetranger problem - if you can beep to a higher rotor RPM (and stay within the power on limits of N2/Nr), then you will get a bit more power (power = torque time RPM). Whether you're on the good or bad side of the lift/drag vs. AOA curve is another matter. In general, if you're that tight on power, you're probably asking for trouble sooner than later.

[OEI and Still Flying]

Just to throw another angle on it.

Quote from the book

Exceeding the limits of 810c TOT or 100% may cause N1 topping with resultant rotor droop.

And all the beeping in the world wont get you out of than one!!!!

Can you imagine @ 50feet and the N1 starts to die a death.


I think the bottom line is that as a pilot if you are depending on the beep to give you another 2/3% on the NR to get you out of a spot. Just shut down and drive home.

[SASless]

In the working world...N1 Topping, Max TOT/EGT, is not all that uncommon. Take helicopters high or hot or both and you can experience that on a daily basis. In Twins....both engines do not run the same either...so you can Q splits/Temp Splits/N1 splits and one or both engines hitting a limit before the other or different limits at the same time.

Throw in steep mountainsides....smoke...and a forest fire....add a 150-200 foot longline...and you have the making of a new extreme sport that Hollywood will not dramatize. We are all to old, fat, ugly, and obnoxious.

Hang on....that blonde thing....Nicole...errr....Anna Nicole could play the leading role!;)

[OEI and Still Flying]

Ah SASless

You'll need more than a 150 foot line to carry that blonde with you.

[Steve76]

"When you increase Nr speed, you gain more lift from the rotor system at any given collective pitch setting"

Not necessarily correct.
EG:
The S76 will lift better at 96% - 100%NR than at 107%NR.
The major benefits at 100% NR is reduced T5, allowing more surplus power for departure.
Fuel burn per NM is also influenced by NR with 107% in certain environ's leaning out the burn rate.

Still personally, I would depart and land with 107% set constantly. I figured and extra couple of % was money in the bank if OEI was required.

With the JR. So long as you are within manufacturers NR Overspeed limits then have the NR up before you need it. To demand it all at once at the bottom of an approach is recipe for settling with power. The JR fuel system cannot and will not keep up demand. If you are not of the habit to approach with a loaded disc then you had better change your flying style.

Higher NR will accomodate more TR control as well since it is operating at (roughly) 6 times the revolutions of the MR. It will manifest problems will in advance of the MR.

All this information is from personal experimentation and via PPRUNE discussions with Nick Lappos, who has abandoned us for the dark side .... :suspect:

[Capt Hollywood]

This is aimed mainly at any Australian Kiowa pilots.

The Bell 206 Jetranger has a vne of 69 knots with a front door removed. I dont think I've ever seen doors on an Army Kiowa, do you seriously hack around at no more than 69 knots when you are operating or is their some difference in the airframes that allows a higher airspeed.

Cheers,

Hollywood :cool:

[centerpage]

I am a former US Army OH-58A/C guy. The US Army Kiowas had a Vne of 100 KIAS, doors off. Supposedly, speeds faster then that resulted in a form of control reversal - the aircraft response would not always follow a predictable pattern for a given cyclic input. One of the practical reasons for this limit was the back doors, with the original handle design, would blow open in flight. In cruise this was not a problem; however, landings were a different story. The reason for the slower 206 Vne is probably due to several factors - actual airspeeds flown during certification, etc. Hope this helps.

[Capt Hollywood]

G'day centerpage,

I had heard of the control reversal problem. 30 knots is quite a difference between the military and civilian version of essentially the same fuselage. (At least they are to my knowledge, feel free to correct me!) I suppose I'm wondering if the main difference is the fact that one helicopter is operated by military personnel and the other is used predominantly to carry civilian paying passengers.

Anyone else?

Cheers,

Hollywood :cool:

[B Sousa]

Done both 206 and OH-58 with no ill effects. I think Centerpage hit it with Certification.

[Shawn Coyle]

There is no such thing as control reversal in the doors off condition, and I really wish that someone would get that taken out of the flight manual supplement for doors off in the 206.
It stems from the original 206A model which when flown at very light weight with the doors off, had what is known as negative static stability.
This means that if you trimmed at 60 KIAS and noted the cyclic stick position (Longitudinally), and accelerated to 70 KIAS and held 70 KIAS and noted the longitudinal cyclic position, the position at 70 KIAS would be slightly aft of the 60 KIAS position.
But if you weren't measuring it, you'd never notice because the change is so small as to be barely measurable (and there is no force trim in the 206 for you to notice any stick forces).
As the 206 series increased in empty weight, or if you flew it at something other than empty with nearly no fuel, the problem evidently went away, but it stays in the supplement.
But there never has been a stick reversal (i.e. push the stick forward to make the nose go up).
The OH-58 was not subject to the same certification rules (or possibly interpretation of the rules) as the Bell 206.
The Canadian Air Force flew the Bell 206BII to 100 KIAS with the doors off and found no handling issues.

[Aser]

Shawn,
What about the blown doors? I remember reading it somewhere also, I'm not sure if about the 206 or other helo.

[rotorfloat]

I was taught that all the 'negative static stability' stemmed from the disruption of airflow (with doors off) to the horizontal stabilizer on the tail, which normally would produce lift downwards to assist in longitudinal stability.

...or something like that :8

[Capn Notarious]

Just a question from a non pilot. Doors in or out of position must surely effect the centre of gravity, in addition to the air flow through the fuselage. So what problems does this pose?

[Gibbo]

The back doors issue is a consideration for the OH-58 and I have had the back right door pop open in flight a couple of times. It only becomes evident on landing though and is a bit of a fright the first time it appears in your peripheral vision. I vaguely remember a lower VNE for one door only removed, or back door off in the Kiowa, but it was a while ago; current recce guys?
Gibbo

[auskiowa]

The Australian Kiowa has a Vne of 100kts with any combination of doors removed up to 3000' DA. For every 1000' above that, the Vne is reduced by 1 kt.

[Hilico]

Capn Notarious, the doors (like lots of other things on helis) are very light; and two of them are right under the rotor and on the CoG, so it wouldn't move whether they were there or not.

[B Sousa]

Back to Gibbo. I can only guess, not being that much edjewcated, that flying with rear doors on, front doors off may give a bit of a problem; if you get out of trim and put some excessive air pressure in the back seat area......Probably would pop a door....

[Shawn Coyle]

I don't know what might cause the negative static stability - the effect of the airflow on the horizontal stab sounds plausible.
The point is that there is no such thing as 'control reversal', and that the whole thing is a carryover from a very lightweight Bell 206A model.
And yes, having front doors off, and flying out of trim has the possibility of doing strange things to the back doors. It also has the potential to do strange things to the static ports and upset the alitimeter.

[Capn Notarious]

Shawn thank you for taking the time to answer, will you be at Helitech this year?

[B Sousa]

"It also has the potential to do strange things to the static ports and upset the alitimeter."
Dam, Shawn..........Gonna have to check on that one, never look at the guages with the doors off, its too scary outside. ha ha

[John Eacott]

It also has the potential to do strange things to the static ports and upset the alitimeter.

Shawn,

That's a new one on me: could you explain why? With the static ports for'd of the front doors, and an airflow dam around the aft end of the ports, how can doors off operations create a problem?

Having checked on many ocassions when the doors have been off, I've never seen any perceivable variations in any of the pressure instruments.

[thecloud]

Could it have anything to do with all the "trimming" that the civilian aircraft have not particuarly well secured throughout the aircraft ? as I'm flying these things in the hot, would appreciate 100kts with doors off.

[B Sousa]

Cloud
You could make it a bit nicer by installing AC. Unless its mandatory for flying doors off........I know how it feels, like a blast furnace.

[Shawn Coyle]

Regarding static ports - they are indeed just ahead of the doors, and I seem to remember it made about 100' difference in pressure altitude in the cruise from doors on.
Next time you fly with the doors off, have some put their hand out in the slipstream just behind the static ports - you'd be amazed at the 'bow wave' effect it will have.
Doors on or off, yawing the machine at speeds below 40 KIAS can drop the indicated airspeed to zero when you are still clearly moving at about the same velocity, as what were static ports become pitot ports.

[SASless]

Shawn dear fellow....we are talking Jetrangers here...whats a few hundred feet on the altimeter or whether the Airspeed indicator is off a bit....we are looking outside are we not? You want to experience unusual events...fly a Hughes 500E with no doors at 125 Knots....talking about wind noise and trim changes blowing things around!

[Gibbo]

..............and I am not admitting to flying out of balance; the door just blew open sir!

[John Eacott]

Shawn,

Must take exception to your assertions about the static ports/doors off ops for the 206. Certainly Next time you fly with the doors off, have some put their hand out in the slipstream just behind the static ports - you'd be amazed at the 'bow wave' effect it will have. I'd be more surprised at why anyone would want to break their wrist doing such a thing :rolleyes: Where does this have any connection with "normal" doors off operations, where the airflow around the static port would be much the same as doors on, since any turbulence/airflow disturbance would occur well aft of the ports?

[Capt Hollywood]

Thanks to all for posting, turning out to be an interesting topic this one.

Hollywood :cool:

[Shawn Coyle]

John:
You would be surprised at how much effect things behind a static port can have.
SASless is right - we don't really care about what happens as we're flying VFR, and it may make a smidgen of difference on the IAS, but the important thing is that the presence / absence of the doors does have an effect.
Similarly, on the UH-1N and UH-1H, the wirestrike protection fin is close enough to the static port on the pitot/static head that with sideslip, the fin will affect the static port for about several knots of airspeed difference, and up to about 200 or more feet of altitude.

[SASless]

Shawn,

I would be more interested in the loss of climb rate caused by the absence of doors...along with increased fuel consumption as well. Those negative effects have more importance than instrument readings in my view. Not to mention seeing the bossfellah's expensive interior heading out the door (towards the tail rotor). Sticky paste and velcro particularly in the summer time can easily come unstuck at the most in-opportune time.

[mugsy]

A Longranger engaged in power line work crashed near Vereeniging today, 6th April. The cause appears to be a cracked air line between the governor and Fuel control unit. No fatalities or injuries but the machine is badly damaged.

I'm looking for info on similar problems with that air line.
Another L3 did a forced landing some years ago. After talking to the factory we checked that the plastic clamps between the stainless steel pipes on the C30 engine were correct. Everything appeared normal. We did a Chadwick check on the tail rotor and MR, no unusual vibe. A new pipe was installed and the machine signed out. About 5 hours later the identical, new pie failed and we had another forced landing. Hours were spent looking for a high frequency vibration from anywhere, without sucess. Long story short, another pipe was installed and the engine is still going strong.

I want to get an idea of how common this is with the L3. Who else has had the problem. Hope to hear from you.

[mini]

Mugs,

two quick ones:

Better off in Rotorheads (mods...)

Given the machine went down today, very quick diagnosis?

[mugsy]

Yup, when the engine goes down to ground idle and a pipe is hanging free it seems pretty obvious.