I flew the Bell204B (lycoming engine) and the Augusta Bell 204A (rollsroyce engine) in Iran in the early seventies. The AB204A was based in the mountains for oil exploration (top rig helipad was 12,000 feet) and the Bell 204B (on floats), I flew in the Persian Gulf.

Not a lot of time, about 1,000 hours but a quality aircraft, a derivitave of the HUEY, I believe

The 204B was actually the first "Huey" it was designated the (A) then (B)with changes. Next out was a different body and designated the (D) which after changing from the L-11 to L-13 engine became the (H)
The (C) and (M) were 204 bodies with 540 rotorsystems and bigger engines and used mainly for gunships. both the C/M had shorter tailbooms as did all 204s, and not real good where tail rotor authority is a must. Other variants of the (D) were the (V) for medevac and Electronic surveilance (E) The Air Force and Navy also had 204 bodies with side exhaust engines.
The (D) body evolved into the 212 or (UH-1N) and is today further made in to the B412. Or as is said the 212 is a Huey with two engines and the 412 is a Huey with two engines and four blades.
Im sure Lu could get in here and give all the finer points, but these are just the basics from one with a couple thousand hours of (Pilot Time) in them.

[ 06 January 2002: Message edited by: B Sousa ]</p>

Helmet Fire, I remember that list you posted above, very good. Another pretty amusing 'publication' that used to be popular among the 9, 5, 35 SQN rotorhead fraternity, and elsewhere, was the 'Seagull' or 'Eagle' codes, don't know if you've run across them.
You could transmit the word 'Seagull' plus a 3 figure number, and see the other formation crew members hurriedly consulting their list to see which piece of abuse you had just sent them.
Some good examples were:

"You sir, can f**K right off!" (Seagull 500, as I recall).

"If it don't fit, overpitch it!"

"I love the f**King Air Force, and the Air Force loves f**king me!"

And one of my personal favourites - "Seagull 571!" (Show us your t*ts!)

One thing about Hueys, you could be assured that people flying just about any other type would come out with 'Yeah, I'd love to have a go at flying them.'

And fair enough too, what a classic and excellent machine.

Arm OTW,
dont know the list - but would love to see it!

An NZ mate told me a great Huey story: he took a SkyHawk (when they had them!) pilot for a ride. Each time he would hando over the controls by gesturing with his left hand over the center console, he would flick off the HYD switch, then when fighter jock would strugle and sweat he would take over and flick HYD on again to demonstrate how he could fly the aircraft with just his fingers!

The fighter jock still believes all Huey pilots are incredible!!

Mind you, a good Instructor could hover a well tensioned (and light) aircraft with two fingers on the cyclic with HYD off.

<img src="cool.gif" border="0">

600+ H1's, 250 BH205 and BH212. The best I have ever flown. I think th main difference between the H1 and 205 is larger (AH1?) TR on the right side and another hydraulic system.

Flagrent Grey IRWQC 82-25
j

Does anyone out there fly a Huey?
 

Have recently visited Vietnam as a Trainer delivering customer service and SEP training to VN's cabin crew. Whilst there became fascinated with what went on during the war. Have read lots of books and watched Apolocypse Now about four times! Cutting to the chase, eventually, I would love to have a ride on a Huey. I have become very interested in helicopters and am also considering taking lessons to fly one. Can anyone tell me how much it costs to learn, how long does it take? are there many different ratings etc?. .I was a CSD with BA up until a year ago and am now just north of 40 years old, do I stand a chance of becoming a rotorhead?

dooroneleft,

Yep, I fly one (used to). Got about 2,500 hours in them. Great helicopter, very forgiving (as far as helicopters go). As far as learning in one, unless your last name is Rockerfeller or Rothschild or something, I'd say forget it. Learning to fly, civy side, is very expensive.

I fly one too (well almost Bell 205 A-1) the company I fly for has got seven of the beasts. Always an eye-catcher every where you go. we have a check pilot on the team. The cost is pretty high nearly GBP1500,- an hour (Euro 2300,-). The question is will anybody let you!

If you are interested in helicopters in Vietnam, read Chickenhawk by Robert Mason, published by Corgi, ISBN 0-552-12419-2.

It goes right thrrough his flight training and his experiences in Vietnam. this is the book that originally got me interested in helicopters. It has got a lot to answer for.....

R

Thanks CyclicRick. Can't believe the cost per hour. Are you sure? You are a very lucky guy being paid to fly a Huey. Every now and then I log on <a href="http://www.vhpa.org" target="_blank">www.vhpa.org</a> just to hear the sound of the rotors, now how sad is that?

Draco. I have just ordered this book from Amazon, should have it in a day or so. Will it have the same effect on me?. .I think I am already hooked, however. Having my first lesson in a couple of days in a Robinson R-22 Beta at Redhill in Surrey.. .Now be honest guys and gals, what do you think of the Robbie. Is this the right helicopter to sart on?

There was an interesting thread on Hueys a few weeks ago. . .Click here<a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=11&t=001750" target="_blank">Anyone flown a Huey?</a>

Dooroneleft,. .I (as you may imagine!) think the Robbo's an excellent Helicopter to start on - as affordable as anything to do with Helicopters can be; light, maneouvrable (i.e. fun); twitchy enough to keep you on your toes; and worrying enough to have you spring loaded to dump collective if it all goes horribly quiet. Treat it with respect, fly it as you are told, don't try and push the envelope and you need not have any of Lu's worries.

And be warned, flying Helicopters is very, very, addictive.

Robbo Jock. . Think your a bit mixed up. This little thread is on Hueys, not Robbies. Dont you Robbie guys have enough threads , like "Why they fall from the sky", etc., that you cant let some Hueys drivers have fun..... .UH-1,love that puppy. did it in the A,B,D,H,M,and V also flew the Squashed Version AH-1(G)(S).They were fun days....

UH-1N's, now HH-1N's. HC-16 in P-Cola.

Of course, if a squadron has too much fun, they get decommissioned .... <img src="frown.gif" border="0">

Gitmo had 2 of them, remember 158257 adn 158766, both nice, but saw them later on their way thru P-cola on way to Davis, looked trashed, badly. <img src="frown.gif" border="0">

Draco:

Mason's book sparked my interest in aviation and helicopters. It is also a superb and harrowing account of how the experience changed him. . .Years later he wrote another book about his life after leaving the army; you remember chicknhawk ends with him saying how he was done for drug smuggling? . .I've never been able to find the follow-up.

"The 13th Valley" by John M Del Vecchio . .ISBN 0-312-20081-1 is a fantastic book too, this time by one of the grunts that Bob Mason would have been transporting.

Gotta love the huey. 15-20 psi, 70KIAS, 200FPM ROD and WOCK WOCK WOCK.

Another worth while book is Hunter Killer Squadron published by presidio. Follows members of 1/9th CAV in SE Asia. Harrowing, mad, heroic stuff. <img src="eek.gif" border="0">

Chickenhawk 66

Mason's followup book is called Chickenhawk: Back in the World ISBN 0-14-015876-6 published by Penguin. It's on the shelf behind me.

Nothing like as good as the first one, little about helicopters, but quite a sad story about his gradual disintegration and eventual recovery.

Dooronleft

Try to read the first sections of the initial book before you go for the trial flight. If you can't get it, let me know you address and I will pop a copy of a few pages in the post asap.

R

[ 20 February 2002: Message edited by: Draco ]

[ 20 February 2002: Message edited by: Draco ]</p>

If you want to browse a very good web site of my old unit, check out 176th Assault Helicopter Company. You might have to search the US MSN to locate, but well worth the time. All true, no Hollywood.

Later,

Don't worry your not that sad, we get people ringing up every day wanting a flight a type rating or just to have a peek in the hangar. I'm addicted to the sound of a Merlin with just a little boost at 300MPH just lifting the nose for a gentle barrel roll..sad? No-way I'd sell the wife and kids for a cabby in Spitfire IX.. .One day....one day!. .Take a peek at our web site for a drool if you like <a href="http://www.agrarflug-helilift.com" target="_blank">www.agrarflug-helilift.com</a>

PS. If anyone out there owns a spit and will take me for a ride or a type rating I'll renounce helicopters as smelly vibrating noisy slow lumps of badly made c***. I know it's heracy but...

Gray 14,. .That is a great web site, here is the URL:

<a href="http://members.aol.com/mm27176th/" target="_blank">http://members.aol.com/mm27176th/</a>

I had quite a few friends in the Minutemen/Muskets back in 1969-1970. When were you there?

Nick. .D 1/1 Cav "Sabres" Chu Lai

Low-G pushover's in Huey or Cobra
 

Could someone with lot's of hours in the Huey or the Cobra, please tell me from experience whether they roll right in a low-g push over, or whether you just lose control power.

Many Thanks
CRAN
:)

Huey Tail Rotor
 

As any D model Huey pilot will tell you, she's not too good hot & high. This is because the tail rotor is on the wrong side (left - and trying to pull air through the vertical fin). It also spins down at the front, away from the rotorwash, losing even more effectiveness.

My question is why? Was this a design flaw? Vietnam photos circa 1972 show formations of Hueys, with a mix of left & right tail rotors and as, with the more modern 212, they spin up at the front.

The Bell 47 spins the same as the early Hueys but it of course has no vertical fin to impede the airflow.... as such, I wonder if they just copied the design, without much thought?

Similarly the Lynx tail rotor spins down at the front whilst the earlier Sea King spins up....... pourquoi?

Any venerable Huey design gurus out there?

The direction of spin is a contributor to the issue of tail rotor thrust, but it becomes important only when a limited marginal design is fielded. The power capability of the tail gearboxes, the pitch range of the tail rotor, its rpm and blade chord all conspire to make the maximum thrust what it is. When the tail rotor proves to be marginal, the easy fix is to flip it over and add that few percent of improved thrust back, since no components are changed (as long as the gearbox maintains adequate lube when upside down.) Any other substantive change to make more thrust usually means the entire tail rotor has to be changed, an expensive proposition.

In other words, flipping the tail rotor makes an unacceptable tail rotor now marginally better. Actually fixing it by creating more thrust would be better yet, but much more expensive.

Anyone?

I was in a H model Huey, in a 4000+ft/min updraft (I dont know exacty how much it was as the VSI only goes to 4).... when 1. it suddenly stopped or 2. we hit a downdraft.

We were well less than 0 G, as witnessed by the bags of cargo that hit the roof then 'floated' forward.

The acft pitched to 50+ degrees nose down and rotated rapidly to the right. (From memory it wasnt a violent or bumpy rotation, like 'jack stall' or RBS)

Needless to say, flew home to change my shorts!

Looks like they put the tail rotor back on the "wrong side".

See:

http://www.bellhelicopter.com/conten...upgrades2.html

CRAN :

I'm not a Huey driver ( hey - anyone out there willing to change that ? ), but R22s suffer in exactly the same way.

From memory, under negative G there will be an uncommanded roll right in a helicopter with an underslung rotor system and counter clockwise rotating main blades. And you probably know this bit but the instinctive left cyclic to counter the roll will reduce the mast-hub clearance even further . . .

You just don't do 'em, is the simple answer, unless you're keen to chop your mast off!

Thanks chaps, just the answer I needed!

CRAN

Once you've had the mast strike, it rolls in all sorts of directions. Then you hit the ground.

There was a technical paper on tail rotor design way back in the 1950s that said top turning aft was the best way to go.
Why were the various machines made the other way round? Could be anything from not having to re-qualify a new gearbox to not-invented-here syndrome.
The Lynx changed tail rotor direction of rotation and it made a world of difference to handling, performance and noise.
All the civil Bell 205 series appears to have the tail rotor top going aft.

Hi, tone-uncage-fire!

Excuse my uneducated question: What is a "jack stall"??

3top,:)

1. Jackstall occurs when the aerodynamic loads on the blades overpower the hydraulic jacks controlling the swashplate, causing control reversal. Cause and symptoms similar to RBS.

2. The roll during zero - g conditions is due to the sideways push of the tail rotor creating a rolling moment about the head (think back to tail rotor drift and roll u studied at groundschool).

3. Anything less than +ve g and helicopters definitely do not mix

I agree with the "DON'T DO IT"...
I hit similar up/down draughts in the sierra nevadas in Spain on a ferry flight back to base last year, the only thing that happened to my 205 was loss of RPM! All the horns and lights went on and frightened the c... out of me but instinct luckily took over and I dropped a bit of collective and all was well.
"Helis and -G don't mix" Well not exactly, you can play a little bit with rigid rotor systems but very gently, but not with teetering systems....NO WAY!

All the civil 205's have the tail rotor on the right turning lower blade to the front.
I had a thread on this a while back and got some good info on it, worth checking back to mid Sept.

The way I understand it [from verbal stories only] is that the Huey tailrotors were on the left side because of a US army requirement. Apparently the Army boffins thought that it was safer to have the T/R 'pushing' itself on to the output shaft in case of damage occurring to the retaining hardware when being shot at.

I came across a vague reference to this fact, saying that Bell modified the Huey T/Rs to the RH side but was then directed by the Army to return them back to the L/H side.

That's not to say that you can't throw them around a bit, but smooth manoeuvres with positive g are the go; it's also not too much of a drama to throw the collective down fairly quickly with a central-ish cyclic; I just wouldn't push forward on the cyclic at any more than what you would describe as a gentle rate.

Centralize has it a bit off, let me discuss:

Jack stall is caused by rotor stall. The airfoil on the blade shifts its moment to pitch the nose of the blade down at stall, just as the wing of an airplane retrims in stall, and the nose drops. This stall sends large forces into the helicopter's rotor system, trying to force the servos backwards. If the servos are of marginal design, they can be over powered by the stalled blade, and this backdrive is felt by the pilot, in fact, the helicopter gets a mind of its own and is actually out of control. This jack stall is the natural product of the combination of a stalled rotor and a marginal servo system.

Low g is a problem for teetering/underslung/semi-rigid rotors, but is duck soup for other designs. The explanation is that the rotor does not control the helicopter purely by tilting the lift, as is often said in helicopter primers. The moment produced by the rotor is more powerful than the lift tilt, but this factor is almost never explained.

In an articulated system with hinge offset of 4%, about minus 1/2 g is where the controls have little effect, and for rigid high offset rotors, it can be minus 2g's or so before they have no effect.

Nick

jack-stall
 

Nick--have to disagree,a little!
I think most early helo`s reached RBS before reaching jack-stall,and usually pitched up and rolled unless you reduced collective-quickly!That said you could demo jack stall by winding RRPM back towards the power-on limit,and you would feel it on the controls( in the S-55 and S-58(WWIND& WX).In the Gazelle, the flight controls were developed so that the a/c could be manoeuvred hard without fear of reaching blade -stall,by designing the hydraulic control system to limit its output,and give a tactile feedback to the pilot that he was at his control limit,or nearly so,and could adjust to compensate,without fear of "stalling",and whilst flying "eye-balls-out"; an admirable aid to any tactical helo pilot,manoeuvring hard even close to the ground.Pity it had to be the pragmatic FFrench who devised the system.!!On the early prototype Gazelles,-001,01,02,the system was superb,you could pull nearly 2 1/2-3G,and as you reached the limit the a/c would roll gently upright,in left and right turns,all nice and safe,even when in-the-weeds."Great",we said," well have a couple of hundred of those".Unfortunately, by the time the a/c got to prod. std., the tailboom had been lowered,the cabin had reduced stiffness,due to the door for the winch,the u/c was now different as you could get grnd. resonance,due to the door and tailboom mods.,and the control -jack manufacturer had changed, and that is why at jack-stall the Gazelle rolls the same way at the limit in both left and right turns!!That said ,if you`ve not tried one ,Nick,go and do it; it`s like getting out of your Olds/Chevy/Plymouth,and getting into a Ferrari,or BMW M-class,or if you may be a Harley-D "biker",get a ride on a Kwik-Kwacker ZX-9RR,or at a lower level,first night with a new mistress- so I`ve been told!!;)

sycamore,

Good point of view, and great story about the Gazelle, although I do disagree in that a loss of control is a very poor way to prevent stall (could be the tree you are avoiding is worse for your rotor than some stall induced loads on the controls, for example).

The point I am sticking to is that jack stall is Caused by rotor stall, because the blade pitching moment increases due to rotor stall. Yes, one might start earlier than another but they are both part of the same physical situation.

Look at the lift and moment plots on this paper (Cn is the normal force, like CL, and Cm is the blade pitching moment):

http://ho.seas.ucla.edu/AeroMEMS_htm...es/Control.PDF