Bell 206: JetRanger and LongRanger

[206Fan]

rEy-HxMah14

[Carbonok]

Thanks for your reply, superb inspiration.
Anyone else offering a great (blue if possible) paint scheme for a high skid early model?
3 views still most welcome.

Thanks and regards.

Carbonok.

[Panev]

Hi everyone.
I was wondering if anyone has a good explanation why there is a gurney flap installed on the leading edge of the upper side of horizontal stabilizer on Bell 206 B3. I think it has something with the stability in low airspeed, and that it spoils the airflow over the stabilizer during flare to prevent staying with high nose up position, but I'm not completely sure. Thanks in advance

[rotorfossil]

It prevents the tail plane applying excessive nose down pitch in autorotation by disrupting the airflow over the top of the tailplane, otherwise the rear cyclic travel would be restricted.
The tailplane is sized and configured to apply a download to keep the cabin approximately level in the cruise. The spoiler is simpler and cheaper than a moveable tailplane.

[paco]

What rotorfossil said :), plus:

"The ... Gurney flap ... works by increasing pressure
on the pressure side, decreasing pressure on the
suction side, and helping the boundary layer flow stay attached all the way to
the trailing edge on the suction side. In short, the increased pressure on the
lower surface ahead of the flap means the upper surface suction can be
reduced while producing the same lift over a very wide range of positive and
negative angles of attack. For example, at one extreme, in a high-powered
climb, the negative angle of attack of a horizontal stabilizer can be as high as
-25°. In autorotation, it may be +15°.

On the 206, the Gurney flap corrects an angle of incidence problem in the
design that was too difficult to correct directly. Another reason is to induce
turbulence in autorotation, to spoil the lift and make its effect as small as
possible, otherwise the fuselage attitude would be too extreme."

Phil

[RVDT]

At the risk of being flamed I am calling BS so far -

It is not a Gurney flap otherwise it would be at the trailing edge. Its more like a fixed Krueger flap or cuff.

The story I was told is that it softens or makes the stall of the stab less abrupt.

Apparently it used to hang on a bit later than desired and stall abruptly with a sudden pitch change so Panev you could be right with your assumption.

Could also be BS as well but makes more sense than the other explanations.

Someone out knows the real answer.

[paco]

My explanation was from a Bell engineer, but you'll get a different story from each one of those as well :)

Phil

[wrench1]

Panev.

The piece you refer to is not a gurney flap. RVDT is correct, those flaps are only mounted on the trailing edge side. And mainly on vertical fins.

It's technically called a spoiler (per Bell documentation). The L models, 407, 222 series, etc. have slats.

Like others noted, you can get their purpose de jour depending which engineer you talk to. But its safe to say, the spoilers and slats are there to change undesirable airflow over the horizontal stab.

W1

[paco]

Spoilers do what they say, so obviously too much lift is being produced in some stage of flight.

Phil

[rotorfossil]

It's quite simple. The tailplane's primary role is to provide a downthrust in cruise flight to keep the cabin level. The upthrust from the airflow from below in autorotation is unwanted, hence the spoiler.
You can detect its effect if you enter auto gently with a fixed cyclic position. Initially the nose drops as the tailplane is unstalled in the negative sense. Then the spoiler disrupts the airflow over the top of the tailplane and the nose rises again.

[Vertical Freedom]

rotorfossil is totally correct, also known as a 'lift-destroyer' !

[[email protected]]

You can detect its effect if you enter auto gently with a fixed cyclic position. Initially the nose drops as the tailplane is unstalled in the negative sense. Then the spoiler disrupts the airflow over the top of the tailplane and the nose rises again.not totally convinced by that as generally all helicopters go nose-down when you lower the lever, just as they pitch nose up as you raise the lever. ISTR it's called instability with collective pitch or something similar.

[Evil Twin]

Also the horizontal stabiliser presents a nice big flat surface to push on as the aircraft descends which adds to the nose forward attitude. Probably haven't made that comment as clear as I could have but hey ho.

[[email protected]]

And I should be clearer in that it is the rotor that flaps forward or backward when you lower or raise the lever - how much the fuselage follows that is subject to other factors (control rigging/mixing for example).

Equally the resulting fuselage attitude in steady state descent/climb/auto is much more affected by other aerodynamic features such as the tail stab as Evil Twin points out.

[bront]

Can someone tell me if the low RPM horn can be heard over the intercom ie. in your headset or just via the cockpit speaker?


Thanks

[helonorth]

I have flown a few dozen different ones and they were always a just a horn coming from a speaker.

[helicopterray]

It is only through the speaker, the system is not wired through the audio system.

[Omani trooper]

Phil any idea what an L1 with a c28 will burn an hour

[tottigol]

Phil any idea what an L1 with a c28 will burn an hour


About 250 lbs/hr

[DOASO]

Looking for some help from all you 206 experts out there....

I manage and fly a 'newer' 206B3 out of the local airport. It is always well maintained to 135 standards and has under 4000TT. If it matters, it has Van Horn T/R blades and a Lord Elastomeric bearing which are a few years old.

I've now had two airplane mechanics (mostly unfamiliar with rotorcraft workings) from different airports randomly walk up and tell me they've heard my helicopter come and go hundreds of times over the past few years, but recently there is a high pitched whine coming from back which they hadn't heard before. They both said you can't hear it until the helicopter has passed by them, so they are facing the back of the aircraft. Nothing has changed that I can think of which would account for the new noise. My first thought was possibly a hanger bearing going bad, but they were all checked out during my recent annual inspection. Any chance it's the T/R gearbox trying to warn me before it fails? The chip detector is clean....

I didn't pay much attention to the first guy, but now two?! I'm not overly concerned but am starting to get curious. Thank you in advance for your thoughts.

[formerlongbox]

If it’s high pitched I would be looking at engine, unlikely from thenTR, you would have vibrations.

[Encyclo]

The Bell 206B T/R gearbox is simple and very reliable. If the chip detector is clean and the oil is clear, nothing to worry about.

The Van Horn blades are known to be quieter than the Bell metal blades; could this be the difference they are noticing?

The LORD T/R trunnion STC is a great improvement but would have no effect on noise type/level.

Fly Safe, Always :ok:

[SandBlaster214]

I'd concur with the two previous posts. If the T/R and/ or gearbox are not producing any "secondary" indications such as vibrations, metal or excessive heat, I'd look elsewhere, and as "formerlongbox" suggests, eyeball the engine. Another suggestion; years back I had an issue with an oil cooler blower or "squirrel cage". The impeller had somehow received a slight deformation to a couple of "vanes", which set up what was described as a shrill whistle at full RPM. Hard to pinpoint as it couldn't be heard from the front or on the ground close up as the engine and rotor noise masked it pretty well, but it could be heard from a distance aft and away from the helicopter. Good luck.

[chopjock]

How about do a flyby once for someone to hear the sound then do another flyby engine off and if the sound has gone then it was coming from the engine...

[timprice]

Recently had noise coming from mechanical fuel pump on engine, I had heard nothing like it before.
Best Wishes
Tim

[formerlongbox]

The fuel pump is a good call, I have also had this, easy to check, remove and turn the spline, if it’s tight that’s your boy. I also had a bad bearing in the accessory gearbox, sounded like turbine, sadly only way to eliminate is swap out.

[bront]

How about do a flyby once for someone to hear the sound then do another flyby engine off and if the sound has gone then it was coming from the engine...

Yeah, that'll work...…...Not. FFS!!!

[wrench1]

high pitched whine coming from back which they hadn't heard before. They both said you can't hear it until the helicopter has passed by them, so they are facing the back of the aircraft.
What phase of flight were you in: taking off, cruise, letdown, etc? Were you in the same flight phase both times? Was the noise steady, pulsing, or other? Have you physically changed anything, no matter how minor. on the aircraft since either mechanic has been near your aircraft?

Have chased many "unique" sounds over the years. FYI: Sometimes how a person hears the noise and how sound travels doesn't always indicate where on the aircraft it may come from.

[DOASO]

Update on the noise they were hearing....

#3 bearing in the gearbox was cracked and eventually started making quite a bit of metal. Engine is repaired and sounds normal again.

[OvertHawk]

Update on the noise they were hearing....

#3 bearing in the gearbox was cracked and eventually started making quite a bit of metal. Engine is repaired and sounds normal again.

Thank you for taking the time to come back to us an tell us the source of the noise!

OH

[ericferret]

Interestingly a vibration search with a Vibrex would have probably found this.
A friend of mine sadly no longer with us was searching for a vibration on a 206.
Hand holding an accelerometer he worked round the aircraft.
He determined that there was a peak vibration at 6000 RPM.
The engine was stripped and the output gear was found to be cracked.

I tried the same technique on a BO105 and identified a vibration at a speed that didn't appear to correspond to
any of the rotational frequencies.

Two days later the aircraft suffered a main gearbox fan drive failure and further research showed that it rotated at the frequency we had found.

Close but no banana.!!!!!!

[Pittsextra]

Idling my weekend away picked up this trivia https://www.thisdayinaviation.com/10-january-1966/

is there any recommended reference book for the history/ design/ development of the aircraft? I couldn’t see anything obvious.

[Tickle]

Yes, check out this book:

https://www.amazon.com/THEY-CALLED-RANGER-Fred-Maupin/dp/1882824571

https://m.media-amazon.com/images/I/51unBepX0gL.jpg

[paco]

There's a Bell 206 group on facebook you might be interested in

[VM325]

Yes, check out this book:

https://www.amazon.com/THEY-CALLED-RANGER-Fred-Maupin/dp/1882824571

https://m.media-amazon.com/images/I/51unBepX0gL.jpg
Does anyone know a source for this book in the UK?

[albatross]

Does anyone know a source for this book in the UK?

I use this site to search for books.
https://www.abebooks.com

[VM325]

I use this site to search for books.
https://www.abebooks.com
Yes, I've tried all the usual UK suspects, $20 for the book, $35 to post from the USA.
Doesn't look like anyone in the UK/Europe stocks it...

[Pittsextra]

I had the same problem so I’ve bought 10x if you PM me ill happily send you one if you’re one of the first 9!

[VM325]

Idling my weekend away picked up this trivia https://www.thisdayinaviation.com/10-january-1966/

is there any recommended reference book for the history/ design/ development of the aircraft? I couldn’t see anything obvious.

Pitts, thank you, message sent..!

[Minquanlu]

Great bird. Very reliable. Worth a keep. Worth every dough.

[206 jock]

We're getting to the tipping point where a late low hour 206 is not much different in price to an early 505. OK there's still a bit of difference but they are in the same ballpark nowadays.

Hypothetically speaking, which is the best home for the money? Yes the 505 is more modern, has more advanced technology etc but it doesn't go much faster/carry much more and it's looks are 'challenging'.

I have owned 206s for over 20 years so would like to think that I understand their strengths and costs. The 505 on the other hand is a mystery to me and I have always been wary of the Arrius engine.

[PhlyingGuy]

Depends on what you're planning to do with it and how many hours a year you plan to fly with it. The 505 is overall much more powerful aircraft, much more safe (easier auto-rotations, latest crashworthy standards, etc), provides a lot more visibility, a lot more comfortable for everyone, and the flat floor provides a lot of flexibility inside.

But, you've owned 206s forever so you know what you're doing with them. if you're only flying 50 hours a year for fun.... get the 206 if looks are that much more important to you. For every other reason, you should get the 505.

My recommendation is getting a demo... you'll love it or leave it in one flight based on all your 206 experience.

[ohsix]

I've been casually shopping for a late-model, clean, 206L for personal use and recently pivoted to looking at early 407s and 407GX birds. I prefer Garmin glass and air conditioning which is rare in a 206L. You're likely to end up in the $1.5-2mm range for a clean 206L4 with Garmin and AC which puts you into 407 territory.

This will be my first helicopter, so I'm far from an expert. I talked to my local Bell rep about a 505 and told him I was looking for a late, low-time 206L and asked if I should consider the 505 instead. He said he can't sell a 505 to a 206L operator due to maintenance requirements.

I also looked at, and test-flew, an older 206L that was listed by a large, US-based ENG group. I caught up with one of their maintenance guys and one of their senior pilots. They operate the 206B3, 206L models, 407s, 505s, and a few A-stars. They've been phasing out the A-stars and 505s. Both had compliments for the 206 and 407 variants, not so much for the A-star and 505s.

[tymiller]

Can anyone help out with an Aeronautical Accessories STC for the 206B Range extender??
Electronic copy please!!
STC SH2889SW
Did you ever find an electronic copy of the supplement for the Aeronautical Accessories 206B Range Extender Fuel System? I have the hard copy attached to the flight manual, but I'm looking for a digital (PDF) copy. I've been to Aeronautical Accessories' website, but couldn't find anything there.

[tymiller]

Did you ever receive a digital copy of the supplement for the Aeronautical Accessories Bell 206 A/B Range Extender Fuel System? We have the hard copy in our CFM, but I'm looking for a digital (PDF) copy.

[Salusa]

Did you ever receive a digital copy of the supplement for the Aeronautical Accessories Bell 206 A/B Range Extender Fuel System? We have the hard copy in our CFM, but I'm looking for a digital (PDF) copy.

You can download a copy from AAI website. (https://www.aero-access.com/tech-reports/documentsearch.aspx)

Will need to create an account first.

Either that or PM me your email and I can send you a copy.

[tymiller]

Thanks for the tip! Creating an account worked.

[RotorRick]

Been lurking here for, literally, years. It's my favorite thread on pprune.org. So many fascinating posts and specific, real world, information. I've posted a "Hi there" post here on the Rotorheads subsection and am happy to finally begin participating in earnest!

Thank you, all!

Rick

[nigelh]

After having both the 206 and the 505 I would say stick with 206 until the 505 is fully sorted ( don’t buy 2018/19 models . I operated mine for about 3 years and gave up due to so many silly faults , both design and manufacture. Other things such as horrible to fly in windy/ bumpy conditions when light plus C of G that was impossible to deal with without carrying big water Jerry cans etc . I would guess that mine was tech for 25% of all revenue flights which was , to say the least , disappointing!!
mother than that it was lovely and great power and viz !

[FH1100 Pilot]

The beauty...genius, really...of the original 206 was that the designers thought to put the transmission over the back seat, *and* tilt the mast forward - two things that the designers at Hiller did not do with the model 1100 (nor did the German designers do with the BO-105). The 206 design brings some structural compromises, like necessitating the infamous bulkhead between the front and back seats. Still, a 206B is almost impossible to get out of c.g. If you run scenarios of "most FWD" and "most AFT" c.g. with a B-model you'll see what I mean. Even a skinny little 170-pound pilot flying by himself can take almost 100 pounds in the baggage compartment and still be okay. When I saw the 505, I knew that there would be unavoidable c.g. problems with it. Which is why Bell could stretch the 206A/B-model into the L-model but we never could do the same with the FH1100. And don't think we didn't try. I'm not familiar with the R-66 but I'd be curious as to how they handle the c.g. difference between a pilot flying solo to a location to pick up four fatties. So I'm with Nigel - the 206 rules!

[RotorRick]

It is my humble opinion that the 206 series will have a long life in the aftermarket. At least that is my hope!

Of course I am biased!

Rick

[206 jock]

After having both the 206 and the 505 I would say stick with 206 until the 505 is fully sorted ( don’t buy 2018/19 models . I operated mine for about 3 years and gave up due to so many silly faults , both design and manufacture. Other things such as horrible to fly in windy/ bumpy conditions when light plus C of G that was impossible to deal with without carrying big water Jerry cans etc . I would guess that mine was tech for 25% of all revenue flights which was , to say the least , disappointing!!
mother than that it was lovely and great power and viz !
I recall that you were excited to be one of the early adopters of the 505, sounds like the expectation didn't match the experience.

I wonder if the 206/505 will be like the Honda NSX...the new one is superior in almost every way but now good late originals are appreciating while early new ones are worth less money.

[RotorRick]

I've often wondered why Bell, in its infinite wisdom, decided to completely disregard decades of history with a perfectly good airframe and engine manufacturer and create the 505. It's a nice enough aircraft, but a more cost effective replacement, or even interim replacement, would have been an upgraded, modified 206 series. Add some new, more aerodynamic fairings, fix some of the existing issues, etc and release it as a evolutionary line of aircraft. Look at the 407.... still kicking... as are many more of the "Legacy" designs.

Seems to me they missed the PR boat on this one. I just read they sold the 505th 505. OK, that's something I suppose. There are advantages to the 505, flat floor, etc. But not at that price point. I was told by MANY older Bell employees at the last MRO convention that none of the older staff was even asked about the 505 design. It all happened behind closed doors far away from Texas. With decisions made my high level corporate. Needless to say, they all pretty much hate it.

If you want a Safran powered aircraft with a flat floor, buy an H125/AS series!

Besides, I find the profile of the 505 to just look like a Jimmy Durante style schnoz. But that's just my opinion.

YMMV

Rick

[ohsix]

My guess is that Bell intended the 505 to be the TBM 700/850/9XX series of helicopters. That is, to be the de facto turbine-single of the owner/pilot. It was initially announced at a sub $1 million price point with Garmin glass, and a class-leading autopilot. I'm guessing Bell thought the clean sheet 505 would be far cheaper to build than a refreshed 206B (206C?) with similar amenities.

[Sir Cumference]

I am having a look at a used L3. One of the MR blades is almost out of time. Are used blades available and do they have to be ''matched''. Sorry for the maybe stupid question but I would rather be in for a single blade than a pair. Van Hoorn, one day!