Gyrocopters/Autogyros

[Wee Weasley Welshman]

I am in the very tentative phases of deciding to buy one. It would be immensely useful if the UK's premier expert in the field were to make himself known to me here.

Alternatively anyone with any experience whatsoever would be more than welcome to make me the beneficiary of their wisdom.

Cheers,

WWW

[PURPLE PITOT]

I too have always had a strange attraction to these weird and wonderfull machines.

I believe there is a guy at Carlisle who specialises in this kind of thing, Roger Savage i think.

I too would be interested in more info.

WWW i hear that you are aflicted with the same rugby players build as me, you might find weight is a problem for many of these designs!

[This message has been edited by PURPLE PITOT (edited 18 June 2001).]

[Shaggy Sheep Driver]

I'd be interersted to hear from someone who flys them. They look fun, but they do have a dreadful accident record. A pilot from our club was killed in one while training somewhere in Yorkshire.

SSD

[Whirlybird]

I've had a couple of trial lessons with Roger Savage up in Carlisle; yes, they are lots of fun. Need hardly any distance for takeoff, and can land on the spot if there's almost any wind at all. Engine failure is no problem; you just float gently down to earth. Landing I managed on my first lesson; take-off is a bit harder, but I can't remember exactly why. Main disadvantage is they're very noisy. Also, there are only 7 instructors in the country, so you might have to travel quite a way to find one.

They're basically fairly safe, and most of the accidents were in the early days when there were no 2-seater gyros, so people learned by an instructor talking to them from the ground; not the case any more. But there have been a couple of accidents recently, which have started the whole safety discussion off again.

There's loads of stuff on the Internet about them; do a search. The best is Mel's Gyro Page; a chap called Mel Morris Jones who flies gyros and lives somewhere in the West Country.

I was originally looking for a cheap alternative to helicopters, and gyros didn't quite make it as they couldn't hover, but they still fascinate me.

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Whirly

To fly is human, to hover, divine.

[SteveR]

There's one based at Rochester. Very swish, all shiny glass fibre, veneer dashboard, gold hoses on the engine. 100 per hour instruction I gather. It never fails to draw a crowd when it's being used.

Steve R

[Wee Weasley Welshman]

Well thanks for that everyone. I'd seen the Carlisle site - he looks like the kind of guy I would want to talk to. I am interested in that M16 jobby with that rotax turbo'd engine - having dealt with 44,000lb of thrust all day I need something with at least a little bit of poke to play with (excluding the missus)...

Will 14 stone of prime welsh stallion really be too much for such a machine? I am a fat barstand but I am also very very short... think of the C of G benefits.... ;)

Cheers guys,

WWW

ps just think of actually landing in your pub beer garden in such a machine, unstrapping and marching in for a pint - you'd be a legend!

[Whirlybird]

WWW,

You might be a legend, but except in mid-summer you'd also be frozen stiff, especially in mid-Wales. The VPM M16 or whatever it's called is open cockpit with your head above the windscreen, and at 70 kts that is coooollllddd. Definitely try before you buy. I'm pretty sure that weight is not a problem though.

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Whirly

To fly is human, to hover, divine.

[Pielander]

There's supposed to be an article on whirling death machines in the August edition of "Today's Pilot".

Pie

[Yogi-Bear]

There was a spate of accidents to quite experienced pilots in the late 60s and 70s (including a very public one at Farnborough). The scene went quiet for some years and now we are recycling with exactly the same type of accidents. Reading those accident reports should be de-rigeur. The two lethal problems appear to be mast bumping and unloading the rotor disc caused by a push-over or turbulence. Can't say much about the former except that it might be an inherent fault of the teetering hub rotor head. The latter is a gotchyer. You must maintain positive G in all manoeuvers. Any unloading of the rotor causes it to slow down and below a critical rpm it will not speed up again. The rotor flails and fails and the ROD becomes something akin to 32ft./sec./sec. http://www.pprune.org/ubb/NonCGI/frown.gif I've seen a film of it happening to Ken Wallis but he was only 20' high, yet amazingly, walked away from it. :)



[This message has been edited by Yogi-Bear (edited 20 June 2001).]

[Wee Weasley Welshman]

I wasn't planning on going as high as 20ft in them... :) ;) !!

Strictly a low level sunny day big boy toy for use in rural rural mid-Wales. I spent all this time blatting around N.Wales in Gazelles and Yellow Wessex's you see and it has rather given me a taste for this sort of thing...

Checking the stats its still 4 times safer than me buying a motorbike...

And I am a careful wee swine.

WWW

[Whirlybird]

WWW,

How about a REAL helicopter? There was a Rotorway Exec for sale in my village recently, not too far from you; it might still be around. £35,000 I think; OK, a bit more than a Gyro, but more fun too :). And I think I saw one in a mag recently for £20,000; if you're interested I'll try to find it again.

------------------
Whirly

To fly is human, to hover, divine.

[Wee Weasley Welshman]

Unfortunately 165hrs mil turbine rotary time has spoiled me somewhat - light piston heli's are not for me.

WWW

[JP5A]

WWW

Having spent the past 30 yrs flying fixed wing and the addition in the past two years of rotary I had my first spin in the gyrocopter with R.C.last Sunday at Carlisle.
Brilliant fun and plenty banter from the many pilots who have built and fly their own machines.One guy told me it only costs £15 p.h.to run his single seater which is a darn sight cheaper than £140 for a Robbo.
We are looking to form a group around our pub crowd and base it in our local farmers field.
For someone used to flying a C401 it was a little disconcerting for the first 10 minutes to be sat,like a pea on a drum,in an open cockpit,but I enjoyed the low level stuff immensly.It's like a flying motorbike and,more immportantly,within most peoples reach.
I must read up on the accident reports but negative g is bad news in a Robbo so I am familiar with that.
Anyway,good luck.I'm sure we are going to see more of them around.

[Negative 'G']

Quote:

"I must read up on the accident reports but negative g is bad news in a Robbo so I am familiar with that."


Why am I bad news in a Robbo ? :)

[ShyTorque]

Negative G,

If you have ever bumped your mast you will know just how painful it can be!

ShyT

[The Nr Fairy]

Yogi :

Slight technical correction. Unloading the rotor disk can lead to mast bumping if not immediately corrected or if a bit vigorous. Bumping is a consequence of unloading, not ( to my mind ) a strictly separate phenomenon.

There are recent accident reports, and if you speak to any R22 instructor I'm sure they'll quite happily explain in much more detail.

------------------
For the last bloody time, it's "The En Ar Fairy" . . .

[Shaggy Sheep Driver]

Yogi

So if the rotor unlaods in turbulence, and unloading causes lead budgie syndrome, and it happens to gyro-gods like Ken Wallis, then surely these whirly aerial motorbikes are complete death traps as the accident record seems to show?

SSD

[Yogi-Bear]

Thank you NRF, It's some time since I last read the bumff so relied on the little grey cells somewhat. :)

SSD, It's only an opinion when all's said and done. These machines appear to handle fundamentally differently from very light helis and a good study of the runes seems called for before embarking. Having read the accident reports over a thirty year period, I do think we re-discover repeatedly what our predecesors have already discovered. Some having paid the price for this knowledge, it seems feckless to ignore their experiences. http://www.pprune.org/ubb/NonCGI/frown.gif

[This message has been edited by Yogi-Bear (edited 21 June 2001).]

[Shaggy Sheep Driver]

Yogi

Absolutely agree about learning from past experiences. but I'm still not sure if these machines are safe. Safe as, say, a production GA aircraft. In other words, if you fly it right you'll have no problem, and flying it right does not require superhuman levels of skill and concentration?

I'd love to know 'cause look interesting ;~)

SSD

[Yogi-Bear]

I can't answer an absolute like that but if you like I'll copy some of the old reports when I can (some searching in old Pilot mags)and give them to you next time. Then you decide. OK? :)

WWW, You can buy an ex-MOD Gazelle on a Permit to Fly now at half the price of a CoA version. Then form a kamikazee (or kote) group? Alternatively, (and that's what you wanted?) a Mini 500 heli (only c£15K) looks equally lethal, to the pilot, that is. http://www.pprune.org/ubb/NonCGI/eek.gif

Whirly, A while back an aquaintance bought an Exec 90 and showed it off to all. After a good look around I said, "Very nice Pete, but where do you put your sandwiches?" He didn't keep it very long, because he was starving. ;)



[This message has been edited by Yogi-Bear (edited 21 June 2001).]

[jayemm]

I saw a couple at Old Sarum weekend before last. Don't know if they were based there though.

[Shaggy Sheep Driver]

So buy a Gazelle, then when the engine is life expired instead of taking out a second mortgage for a rebuilt one, convert the helo into a Gyro?

SSD

[Whirlybird]

I actually had a long chat with Ron Jenkins of the CAA about gyros a while back. He's the sort of chief rotary licensing etc person, don't know his exact title (hope he doesn't read this!). At the time I had a PPL(A) and was close to a PPL(H) and wanted to know how many hours training I'd need for a PPL(G). Anyway, we discussed safety, and he seemed to think they were inherently OK, and that most of the accidents had been due to poor training before it was properly regulated, or poor self-build skills. I must admit what mainly put me off was trusting something with so many moving parts to someone else's DIY skills - or my own for that matter :). But difficulty of flying didn't come into it as far as I remember, and the main snags seemed to be similar to those of the R22, ie negative g and mast bumping if you don't know what you're doing.

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Whirly

To fly is human, to hover, divine.

[SteveR]

I can figure out why negative g might be a problem in rotary aircraft, but what (please) is mast bumping.

(Sounds like a fixed winger getting it wrong on a carrier landing).

Steve R

[Cyclic Hotline]

Check out the US accident statistics for these machines here. (http://www.ntsb.gov/NTSB/Response2.asp?spage=2&x_page_size=100&sql=select+%2A+from+aviation%5Fquery+where+ntsb%5Fno+is+not+ null+and+ev%5Fdate+%3E%3D+%271%2F1%2F82%27+and+ev%5F date+%3C%3D+%276%2F21%2F01%27+and+acft%5Fcategory+%3D+%27gyr o%27+and+homebuilt+%3D+%27Y%27+order+by+ev%5Fdate+Asc)

These accident rates are for gyroplanes only, do not include homebuilt helicopters. As there is (in my opinion) a complete lack of regulatory control over these aircraft, the only way you can get a feel for safety in this category is to review the accident statistics.

I think that Whirly has hit the nail firmly on the head - these machines are being built by people who do not have the first clue about what they are doing. I have seen workmanship so poor on some of these pieces of equipment, that I do not understand how they ever got airborne at all. Of course, the fact that many people do not know how to operate them doesn't help matters any.

I think that a lot of them get completed then spend the rest of their lives sitting around the corner of a garage, otherwise the accident rate would be even higher!

Scary machines, just like homebuilt helicopters!

Can't get that hyperlink to work right. Sorry about the long string.



[This message has been edited by Cyclic Hotline (edited 21 June 2001).]

[Yogi-Bear]

I’ve had a think overnight. Its surprising what the little grey cells can trawl up after sleeping on it. But I’m away from home at the moment so nothing to refer to. Sorry if this is obvious.

The fundamental difference between auto gyros and helis is that a heli’s rotor is powered whereas the gyro’s relies on airstream for rotation. Consequently air flows downwards through a heli’s rotor but passes upwards through a gyro’s. A heli’s rotor is tilted forwards in s&l flight but a gyro’s is tilted backwards. Lift is derived from the blade’s AoA to the airstream. The teetering head teeters, to adjust the blade’s AoA automatically throughout a revolution to equalise lift around the disc. If you drag the rotor blades through the air fast enough a lift component causes the forward facing blade to advance and a state of equilibrium can be achieved at circa 200 rpm.

Now any change to AoA caused by turbulence or mishandling will upset that equilibrium. The rotor head will teeter trying to maintain the appropriate AoA resulting in rotor speed fluctuations. There is no power drive to maintain rotor speed regardless as in a heli. In extreme cases, the teetering head reaches its stops. Not only does the inertia of the blade impart a shock to the mast but then insufficient AoA is generated. The distribution of lift around the disc is perturbed, exacerbating the problem. (OK SR?) This is the inherent problem of the teetering head. It appears difficult, if not impossible, to manufacture one with sufficient range for the more extreme flight conditions. In a heli, at least you have the engine to help overcome the perturbations. You’re not relying totally on inertia.

The other condition to cause the same problem is the push-over. When the rotor disc is unloaded in a bunt type manoeuvre, the AoA reduces and with it, the lift component that ensures rotation. The rotor slows. In extreme cases the AoA can become negative which positively and rapidly slows the rotor. It doesn’t need a lot to slow the rotor below a critical speed from which it does not recover its rotational speed.

What price an aircraft that shouldn’t be flown in turbulent conditions? I do think that it has been all too easy to blame the pilots’ mishandling for what appear to me to be inherent deficiencies of the concept. Certainly, not fully understood by their pilots but don’t we all rely to some extent on intrinsic good manners? I’m not saying don’t fly them but, if you choose to…… Do you have your answer now SSD? That’s enough from me. I would rather see the argument pursued by more technically knowledgeable types.
But finally,
Q. Have you ever wondered why these machines have such a low aspect ratio fin and rudder?
A. Well, sketch a blade in on a side elevation just missing the top of the rudder and see how far they are designed to go before de-capitating the rudder! One builder modified his with a taller rudder. Guess what happened? http://www.pprune.org/ubb/NonCGI/eek.gif

WWW: You certainly get 12 out of 10 from me for stirring it! Can you do the same for the Instructors’ Forum? :)

[This message has been edited by Yogi-Bear (edited 22 June 2001).]

[Whirlybird]

Yogi,

That certainly makes sense to me, but I'm not technically minded enough to be certain. Maybe we should ask some of the more knowledgable types from Rotorheads what they think.

------------------
Whirly

To fly is human, to hover, divine.

[Yogi-Bear]

You just read my mind! You do the asking. :)

[Whirlybird]

Wilco.

------------------
Whirly

To fly is human, to hover, divine.

[Rusty Nance]

O.K. Where to start? This is my first post to this forum so I'll try not to stray. First, A properly designed gyro is both easy to fly and very safe. However, the number of properly designed gyros is small. I'll first address the turbulence issue. The stability in turbulence is determined by the point at which the rotor thrust line passes the longitudinal axis. If the rotor thrust line passes behind the longitudinal C.G. when an updraft is encountered the nose of the aircraft will lower into the new relative wind. When a downdraft is encountered, just the opposite will happen. If the rotor thrust line passes in front of the longitutinal c.g. then an updraft will cause the nose to pitch up and a down draft will cause the nose to pitch down, this is an unstable condition. The next question should be, well how do you make the rotor thrust line pass behind the c.g.? By placing the propeller thrust line at or below the vertical C.G. and installing a horizontal stabilizer. The dangerous part of flying a machine that is not stable in pitch is when the propellor thrust line is above the vertical C.G. a SIGNIFICANT nose down pitching moment is created when the aircraft approaches zero g. The rotor itself is somewhat tolerant of low G conditions as long as the time period is not excessive (more than 2 seconds, exact number depends on many factors such as blade weight and airfoil.) Machines that have a high thrust line, low vertical C.G. and no horizontal stabilizer will pitch over severly as a result of propellor thrust when the aircraft is unloaded in turbulance. This is the classic power push over. This event can happen very quickly and even quick reflexes by an experienced pilot to reduce power may not be timely enough. A gyro with centerline thrust and an adequate horizontal stabilizer are not prone to power push over, gust induced oscilation, or pilot induced oscilation.
Keep in mind that this information is abreviated. You could write volumes about the stability of the gyroplane. A good place to gather additional information about gyros is the web site http://www.rotorcraft.com they have a conference section with a couple of useful downloads. One is an excellent article written by Jean Forcade on stability of the gyroplane.
I am a gyroplane CFI in the U.S. and will be happy to answer any specific questions via email. I will be out of town intermittently and away from email for up to a week at the time. I am also the Chief Test Pilot for the CarterCopter and don't have internet access when I travel for those duties. I'll shut up for now and I apologize for the spelling. Not one of my strong points.

[Try_Cyclic]

Fellow rotorheads,

A gyro cannot experience mast bumping in the same way a heli does. There is no mast to provide torque. The rotor is allowed to spin on a bearing.
Negative g is still a problem because it leads to loss of attitude control.
This is true of all teetering rotor systems.
Loss of rotor authority means that the gyro can rotate itself right into the rotor, usually chopping the tail off.


Another area of concern is PIO or pilot induced oscillation. This usually happens with low time pilots who chase the controls and wind up doing a series of porpoising manuevers that get progressively worse culminating in a tail boom strike or other catastrophe.

A horizontal stabilizer of adequate proportions can vastly improve the damping and control response and reduce the PIO danger.

Incidentally, engine failure results in more than "a gentle glide". A steep glide must be entered to maintain forward airspeed.
At the bottom, similar to a heli, a flare is entered to build energy in the rotor.

There is no collective to pull, the flare is used to cusion the touchdown.



[This message has been edited by Try_Cyclic (edited 24 June 2001).]

[Yogi-Bear]

We weren’t overwhelmed in the mighty rush, were we?

Thank you RN and TC. The ideal configuration that RN espouses is presently unconventional in the Land of Uk. I haven’t seen one in England though I’ll bet they’re lurking somewhere. It may well be the way to go but those that fly here today have a low C of G, high thrust line, with all the accompanying deficiencies, as described. http://www.pprune.org/ubb/NonCGI/frown.gif

Using the links from http://www.rotorcraft.com/ :-
A study of http://www.aircommand.com/ will indicate the new configuration. Then refer to http://www.aircommand.com/elite2706.html and notice the degree of modification between the conventional and the new Elite upgrade. I always wondered why nature configured storks and cranes that way. It seems that auto gyros are still very much in an experimental stage and the benign configuration may yet be evolving. http://www.pprune.org/ubb/NonCGI/eek.gif

Dealing with the type you are most likely to buy secondhand, I cannot recommend too highly Peter Lovegrove’s articles in Pilot magazine of August and September 1971. Yes, in 1971 after a spate of fatal accidents. They describe the surprising handling problems of the type of machinery that you still see around today with graphic illustrations of the problems and their consequences. It is sobering reading and this is where we came in. A new spate of accidents is occurring as though it has never happened before. Probably, the articles are still obtainable from Pilot mag. If they can’t oblige then I can, with their permission of course. Just put your life savings in a suitably large ‘Jiffy’ bag and email me for my address! ;) :) 

[Stan Sted]

WWW

I suppose with all those share options and a cut of the profits from your company, a gyro may soon be parked in the garage of the WWW Towers?

PS

A bright yellow gyro flew over my place one evening last week. It looked great but did sound a bit noisy..though it was buzzing along at a fair old lick...a bit like a bee out of hell.
It was flying down the south east corner of the Stansted zone, on a track from Andrewsfield to Stapleford. Might have been doing a big circuit out of North Weald though. Could be a local enthusiast who you could contact?

[This message has been edited by Stan Sted (edited 30 June 2001).]

[ShyTorque]

General interest in gyrocopters?

Take a look at the address below. I found details of this company some 5 years ago and have followed their progress ever since. They may well be onto something big as there does seem to be a market waiting out there.

Perhaps the wider use of these fascinating aircraft is about to begin.

I hope they have the noise problem sorted though. The RAF 2000 that often flies round here sounds like a swarm of bees in a tumbledrier.

http://www.groenbros.com

ShyT

[This message has been edited by ShyTorque (edited 29 June 2001).]

[Wyatt Anderson]

Just a quick note following your ad on PPRUNE.

The man you need is Tony Melody.

He has been building and testing these for CAA, James Bond films and all sorts. He is doing displays all over the world these days. On top of this he is a thoroughly reasonable bloke! He will be more interested in helping get you sorted out properly than helping you unload your wallet.

Please give me your contact details and I will get him to contact you. He will give you some very sound advice. If he doesn't actually sell you one he will tell you what to ovoid and probably point you in the right direction.

Wyatt

[Wee Weasley Welshman]

Thanks Stan. My email address is in my profile for those that wish to contact me.

Cheers,

WWW

[twistair]

I'm glad to inform the community that today Victor Shumeiko called me from the airfield where he tested his new gyro. Vic (shining) reported that they performed first few flights carrying three full-scaled men on board. I've already posted a couple of Vic's gyro pictures, which can be seen from the http://twistairclub.narod.ru/ - then go to English news. Hope to post some
more this week.
Victor's gyro has the original design and a couple of interesting innovations in it which Vic supposes to patent.
Shown is the aircraft with two back seats (side-by-side, sure) removed for test runs. Engine is now 2.5 l injected Subaru converted in Russia. Engine showed 360 kgs thrust. Prop is 3-bladed (181 cm) composite Ukraine-made one.
Victor has build his own rotorhead and used RAf 30' rotor for current flying. We also bought Hollmann and SportCopter(new, painted) rotors to compare them - I believe it may be interesting though somebody surely did this before.
Vic also built his own hydraulic prerotator using local pump and motor. These are extremely heavy and don't last long anyway. This current system allows to prerotate up to 370-380 rrpm. The gyro weights approx. 390 kg empty though I'm sure it will become some
25-30 kg lighter soon. It was named "Okhotnik" which directly means "the hunter".
If anybody is interested in updates, please let me know via e-mail.

Here are htpp://twistairclub.narod.ru/hunter.htm - some poor photos of 3-on-board flights.

[Genghis the Engineer]

Would you care to cross-post to "Flight Test", I think that you might get some interest over there.

Incidentally, is that the Scimitar shaped "Kievprop" being used?

G

[twistair]

G,

we tried KievProp, but this one is different. It's also made in Ukraine but the brand is "Donchak".
There are actually some 4-5 companies in Ukraine who is manufacturing both composite and wooden props. KievProp and Donchak seem to be the best though I still didn't test some other.

[zeeoo]

Hello gents,
I would be very thankfull if you could give here your perception of the gyrocopters... this famous unknown..
What do you think of their safety and building, their piloting.
Have you a good or bad impression....
Would you be inclined to learn more about them or, simply to try them ?

thank you in advance.

Victor

[Martin1234]

Edited to admit I was wrong, thought that you could only find gyrocopter drivers in the accident statistics.

[Aesir]

I have about 35 hrs in Gyrocopters and my father in law has about 100 hrs in them.

We had Air Command gyro´s www.aircommand.com (http://www.aircommand.com/index.html) which we used actually for seismic work! Now we have a JetRanger and RAF gyro.

Gyro´s are not dangerous aircraft in any way, its just the people that fly them that cause accidents mostly due to inexperience and lack of training.

[zeeoo]

Aesir,
thanks a lot, that's the kind of comment i appreciate. very valuable.
Can you tell more about your use of gyro please ?
Thanks

Martin : Aesir proved i can be optimistic... ;)

[edruxton]

Zeeoo

Gyros are as safe as the people who build and fly them. Its exhilarating to fly an open seat and you just can't beat the operating costs.

Ed.

[zeeoo]

Nick,
thanks, I know this forum, and you maybe know I know.
The goal of my question is to find out why gyros have such a problem to be known to the air-public and overall to have the opinion of air-people themselves.
Thanks

[Whirlybird]

Theoretically they appear to be very safe...but the accident rates are pretty horrendous. So why? And why lack of training - they get a PPL like everyone else.

I did a couple of hours in one, way back, and they're lots of fun. :ok:

[XT244]

Theoretical is a Gyro the safest „Vehicle“ in the Air.
Why?
It’s flying permanently in autorotations. :D

Regards

[ShyTorque]

Gyros?

They are loverly.

As on this link here:

http://www.netcooks.com/recipes/Sandwiches/Gyros.html

[zeeoo]

It's a pleasure to ses that the safety feature (or supposed to be) comes in mind quite quickly.

some spoted the main problem : the training and secondly, the building.

get on gents !
I just need to know whether your opinion is good or bad and why..

The reason for that is that gyros are under-developped in the recreationnal and sport piloting but, strangely, at the same, time, this aircraft is the one closer to the Ultralight or VLA spirit : low landing speeds, low weight, tolerance to "amateur" building".

why don't we see more gyros (i ask this to the choppers and Fidex wings people). and Why are they banned or avoided by airports..

Whirlybird : what is your impression about those supposed high rates of accidents. thanks

thanks for your help

[sparks and stuff]

Hi there,can i direct you to our company web site-www.magnigyro.com-you will find details there of our comprehensive range of Autogyros and will only be too glad to answer any questions that you have. Training is an area where much criticsm has been leveled but with the imenent certification of our M16-2000 two seat tandem trainer there will be scope to make improvements in this area.

[av8rbpm]

Don't forget the Carter Copter. Interesting website.

www.cartercopters.com

[CRAN]

Zeeoo,

IMHO the reason why autogiros are under-developed in the commercial/recreational sector is because they are neither one thing nor another.

They cannot hover or take off vertically, so they cannot fly point-to-point as a helicopter can. However, they are not particularly good aeroplanes either - poor forward flight performance and relatively poor handling qualities. They can of-course fly very slowly and have excellent STOL capability without being overly sensitive to gusts, but is that really important for a recreational vehicle? Where could you go (realistically) that a STOL aeroplane couldn't?

I think the fact of the matter is the autogiro, is a bit of a mongrel that doesn't do enough of anything specific to have a clear market to go after. If a nice cheap one was available, why would you buy it rather than a micro-light aeroplane, which is arguably safer and easier to fly - and will definitely be less expensive to operate.

Autogiros are interesting from a high speed flight point of view, there is much work, past and present that suggests that autogiros, or hybrid helicopter/autogiros may hold some potential for increasing the forward flight speed capability of rotary wing aircraft without the cost and complexity of the tilt-rotor configuration. However, this does not have much relevance tp a kit/recreational craft.

In short, I think the question the 'customers' would have difficulty reconciling with themselves is simply:

'What's the point of having a rotor if it can't hover or take of vertically?'

The autogiro has some characteristics that are desirable, but unfortunately the mix of characteristics does not really satisfy the need of any particular market completely. In addition, both helicopters and aeroplanes can do pretty much everything an autogiro can; so what’s its unique selling point?

This is why I believe that machine hasn't found widespread application and probably won't in the future. Though, the relatively low cost and complexity in rotary wing terms will ensure it continues to be a cult favourite amongst rotary homebuilders.

Hope this helps
CRAN
:ok:

[zeeoo]

Hello, Cran, valuable opinions are always apreciated.

many points among those you rise are true, like the fact that a gyro (actually) doesnt do something particular a FW or HELI does.

But you told about STOL capabilities... the simple ability to land with a vertical rate under 2 and flare on a little spot IS a big safety feature..

About hovering.. as you may know, i am around something with a rotor for somes years.. and i finally found the cost between a gyro and an helicopter ( for an amateur recreationnal purpose) is not worth the few minutes you spend hovering at take off or landing with an helicopter..

Hovering is the great HELI myth but in the real usage, exepted for a pure hovering usage, hovering is not that used and not that recommendable.. am i wrong ? most helicopters spend 99 % time performing a flight that a FW could perform far better.

Btw after some investigations, i have the belief that the gyro manoeuvrability is the same or better than a small chopper (i have a particular exemple for cattle mustering in OZ).

Saying that a gyro can't perform cross country travels is not, IMO, that true, but you can say that there are so few models able to do that... not because of the gyro character but because of the availability of an appropriate model.

You said the choice of an ultralight is the good choice, i agree in the fact that it is less problematic (better training facilities etc).
But the gyros have the same potential for this use, UL not being specially designed for cross country.

I think the gyros miss an adequate information, training facilities... they also need some "rumours and impressions" to be killed. and overall a flyable, sellable model.

thanks for your post Cran.

Victor

[ShyTorque]

Auto gyros can probably do 80% of what a helicopter can do for about a third of the cost. It's a matter of whether the other 20% is worth the extra 2/3rds.....

Try typing "Groen Brothers" into Google. Some interesting stuff going on.

[zeeoo]

Thanks shytorque,
don't foget I am a gyro fan, is just try to point out what are the "myths" and "impressions" commonly spread in the whole air-people.

I finally came to the same conclusion as you... 2/3 extra cost for 1/3 extra capabilities are not justified in most of the cases , except for some SAR ops, mil ops, sling works or so.

I think also that the most of the light gyros suffer an obsolete design (i dont talk about groen, or carter), reviewing the gyros design ina modern way should be of interest, that's what i try to do at my humble level.

Thanks

[Genghis the Engineer]

I'm not going to comment on the airworthiness of Gyros per ce, since there are others far better equipped to do so than I am.

But it is clear that in the UK, the gyroplane safety record is quite horrendous - sat around 1 fatal per 8,000 hours. I'd like to venture an opinion of why that is.


If you look at the UK gyroplane community it is small - around 250 aircraft, of which maybe half are in flying condition. This is spread around maybe half a dozen clubs, so there are perhaps 20 flyers in a typical club - and this is right across the country, so they aren't in very regular communication with each other.

Also you've got initial approvals being done by the CAA, in-service airworthiness by the PFA, pilot training oversight by another bit of the CAA; in other words various components of the "system" again not in routine communication with each other.

So the result, in my opinion, is that safety lessons - be they operational, design or maintenance are not being circulated and learned from. The gyroplane community in Britain almost certainly need to be far closer together than they are at the moment, with mechanisms for establishing and ensuring best practice set up and stuck to.

Once you've done that, any deeper issues with gyro safety can probably then start to be dealt with, but at the moment the real problems (in my opinion) aren't really with the basic design of the gyroplane.

G

[zeeoo]

Gengis,
I think you pointed the good (bad) points.
confidentiality is also a problem.. A healthy and communicating community is also a key for success. I would add that Europ misses a good reprentative organization to promote and educate air people, but also to provide the gyro people appropriate communication, safety, building and training issues. Alas, every valuable person, most of the time, tries to get in gyro-business and retains the infos and doesn't participate without commercial intentions ( see tha MAGNI ad left on this thread , thanks mr Magni, we know who is magni and where the magni comes from..).

Thank you

[Dave_Jackson]

I agree with CRAN 99.9%

Compare the specifications of the STOL CH 701 (http://www.zenithair.com/stolch701/7-perf.html ) to a similar gyrocopter.

Perhaps unlike CRAN, I am more skeptical about the CarterCopter, IMHO, no rotorcraft, gyrocopter or helicopter, with 'loosy-goose' blades is going to be able to provide significantly faster forward speeds.


Dave J.

[zeeoo]

Dave,
you are comparing apples with oranges. Witch gyro could you compare to a CH701?

I flew the CH701 for a try, it has good low speed capabilities, but, while a gyro stills manoeuvrable at min speed, every FW is dangerous (try a 180 at low speed or try to tickle the rudders a little much).

each aircraft as its boundaries and limitations.
The gyros has no been designed for high forward speeds, the FW keeping an adantage but not that much if you compare them to the most of UL.

Building a CH701 kit is not the same as building a gyro kit (faster, easier).

The main advantage of UL FW is their range and efficiency not really much.

I am more and more convinced that one of the major disadvantages of a gyro is, actually, it's reputation and a favorable factor you underestimate is : passion... or how could you explain the private r22 fleet ? utility ? no.

to compare the 3 types of aircraft, maybe we should compare them on various missions and uses:
recreationnal, cross country etc etc etc

Thanks

[sparks and stuff]

If you have any reason to doubt the cross country capability of our machines then you might be intrested to note that basicaly a stock VPM M16 Autogyro was flown non stop from Lands End to Wick in just under seven and one half hours and has crossed over water approx 600 miles. This is surley worth a mention. A check of the history books will show that a much lamented Autogyro, the Westlands/Fairey Rotordyne was in the fifties giving lifting proformance in excess of the modern Chinook. It was a victim of ecconomics at the time and not technology limitations. Speaking of limitations, you will find that an Autogyro can be safely flown in conditions that would proclude the use of a weight shift or three axis microlight. Readingthe rather good "The lives of Ken Wallis" will open your eyes when you read about some of the weather he has flown through.

[zeeoo]

A video fromm a russian gyro enthusiast.
check the manoeuvrability : steep turns, sideways, very low speeds, very short take off, spot landing..
a gyro has definitively nothing comparable with a UL FW.

http://www.rotorwingsportstv.com/russian700.wmv

[Grey Area]

Glasgow University have done some work for the CAA on the subject of Gyro stability and control. The main research was into the relationship between the thrust line and C of G. The testing was in a modified 2 seater with an ex mil rotary tp and a PFA gyro instructor/tp doing the flying.

I believe the results proved a link between thrust line and C of G and their effect on stability; particulary the powered push over leading to loss of control. I dont know much more than that I am afraid.

Look here for a bit more info:

http://www.rogersavage.co.uk/news.htm

And here for a useful site:

http://www.jefflewis.net/autogyros.html

Remember you can never have enough fuel - unless you are on fire.

[zeeoo]

Thanks a lot Grey. kind of useful post. It helps to kill some myths.
Victor

From the last link : Why Autogyros Weren't Accepted
At this point we can ask the question of why autogyros were never widely accepted. Early autogyros, although they had a higher speed envelope than airplanes, had a higher drag and so were not as efficient at higher speeds, and absolutely cound not attain the maximum speeds of the faster airplanes. Also, the early autogyros did not have the vertical takeoff and landing capabilities that would have made them more attractive to potential buyers. When the C.30 finally demonstrated a successful jump takeoff in 1934, it was less than a year until the first successful helicopter flew, and only a few more years until the very successful Sikorsky V.S.300 and VS-316. Although helicopters had a smaller speed envelope than autogyros, they were capable of hovering, and their envelope could fill the role that airplanes couldn't. In other words, anything an autogyro could do could be done by another aircraft. Also, Cierva, who was doing most of the development of autogyros, was funding much of the development on his own. When the army ordered the VS-316, that money went in to Sikorsky's company. This gave Sikorsky the funding for development that Cierva was running out of. Without the money, Cierva just couldn't fund the research. And then, on December 9, 1936, Cierva was killed in normal KLM crash. He was only 41 years old. There were other people developing autogyros, but Cierva had been one of the main driving forces behind the movement. Much was lost when he was killed.

Another factor that kept the autogyro from being accepted was purely psychological. Even though helicopters weren't successful until 1935, they had been under development for as long as airplanes. The general public knew about helicopters, and understood the principle of a powered rotor. Autogyros had an unpowered rotor that spun due to aerodynamic forces. Most people did not understand how it worked and so did not trust it. Although it is actually safer than either helicopters or airplanes, people did not realize this. They wanted something powered.

[CRAN]

Can anybody point me in the direction of a production gyroplane/copter with a practical jump-takeoff capability? Do they exist? Are they expensive?

Thanks in advance
CRAN
:ok:

[Genghis the Engineer]

CRAN, you'd be well to go and speak to Peter Lovegrove at British Gyroplanes - he's not all that active these days, but has certainly built and tested such beasts in the not too distant past.

G

[zeeoo]

Cran,
I am not trying to get gyros over helicos or other.
Consider this as a poll. I am amazed of the reactions, i can see a kind of bipolarity.

Cran, of course, except some attemps like Groen Brs, Mc Culloch, Barnett., It is evident that the gyros have not been manufactured enough, developed enough, sold enough.
But you can't say they don't work because they don't sell.
cheers and thank you for your opinion.

Gents,
Could I abuse and ask some questions :
I think that gyros suffer a simple but "old" design.
The bensen worked fine but isnt there a way to improve that ?
It could be linked to Ultralight Helicopters.

1 - most of the airframes are a classical building, but no modern building has been done.

2 - the rotor is still the old teetering one, couldn\'t a 3 or 4 bladed semirigid of hingeless work better, particularly for the major problem : the Negative G situations.

3 - the blade design are quite very simple, no twist, no taper, no tips. coulnd\'t they be more efficient ?

Thanks

[CyclicRick]

I agree with ShyTorque..luvverly with tzatziki and chips.

Just to be boring again, can they actually hover for a few seconds?

[zeeoo]

Rick : yes they can for one or two seconds and can perform jump take off. depending on the prerotation and if they have a variable pitch.

another video link :
http://www.lafhelicopters.com/francais/company/history.htm

scroll down and choose the bandwidth

[RDRickster]

I have to admit that I was impressed by the maneuverability demonstrated in this video:

http://www.rotorwingsportstv.com/russian700.wmv

Much more than I ever thought possible from a Gyro

[zeeoo]

RDrickster,
I was (and i still) a helico lover, but i also admit that i had a mental path to admit the gyros manoeuvrability and wether or not an helico is a good choice for an amateur rotor fan...
you an fly a rotorhead for 15 000 $ complete, with a ultra light license ... what about an helicopter ?..:rolleyes:

Thanks for your honesty .

[CRAN]

Zeeoo,

This has indeed turned into a very interesting thread! I sat down and had a think about the whole problem yesterday lunch time and came up with some interesting ideas. The reason that I asked about 'jump-takeoff' machines in production today, is simply that I've had a rather neat idea about how to produce an autogiro that can hover for extended periods. However, the problem is that it would require a single main rotor system with collective as well as cyclic pitch. The really neat thing is that the controls would remain completely conventional and intuitive to an autogiro pilot and the machine would not be much more complex than a standard autogyro.

There are potentially a number of significant advantages for a recreational rotorcraft of this type:

(1) It can hover like a helicopter
(2) It's safer than a helicopter (No tail rotor, high inertia rotor, easy to fly, low power requirements at low speed, more stable)
(3) It fly’s like an autogiro - always in autorotation
(4) It uses a fixed pitch pusher prop, hence allowing engine to operate at various speeds, giving more realistic access to low cost automotive derivative engines [reduced cost].
(5) It can out manoeuvre a helicopter
(6) It would be quieter than a helicopter
(7) It has better handling qualities than a helicopter
(8) Its more tolerant of pilot mis-handling than a straight autogyro
(9) Much easier to handle following an engine failure than a helicopter

Then considering your three points, you would want to use a three-bladed rotor, with contemporary aerodynamic design as well to further harden the machine against inexperienced pilots.

However, with a full helicopter rotor system, big engine and propeller and additional kit for hover capability, are not we heading towards something that would cost about the same as a helicopter anyway? That’s my only concern...

If the people who have produced 'jump-takeoff' autogyros, have done so at significantly lower cost than an equivalent weight helicopter, then the concept is potentially useful, but if the cost is equivalent to a helicopter, you would probably be better of with a kit helicopter.

Just my thoughts [to stir up the debate - :E :E :E ]

CRAN
:E

NOTE: It doesn't use tip jets of any type, thrust vectoring (other than the MR), or additional lifting props.

[zeeoo]

Cran,

on your arguments, i agree.

I think you know what i have in mind, and be shure i have considered every comment.
The good thing is that we both see what could be desirable to take gyros in another step.

bringing the rotor mechanism closer to an helicopter one could increase significantly the cost/complexity.. but not so...
You told about 3 blades but a 2 bladed can also be improved (any clue?).

The BO108, a heavy helicopter, compared to gyros, flies with a hingeless rigid rotor... couldn't such a system be adapted or copied for a very light gyro ? BTW it could ,maybe, be more forgiving on aerodynamics and use standard dampers (PAULSTRA).

examine the latest gyro heads.. they go really close to a small helico one like the mini 500 or the Dragonfly (that use gyro blades)...their price is (approx) between 2000 and 6000 $...

Yes, every attempt to have a "hop" capability has increased the complexity.
I have a solution to give a hop capability to a teetering rotor at low cost, low complexity.
I have a solution to produce a simpler swashplate w/colective/cyclic..drawing are on progress...

I think the costs can be lessen by a new variety of offers..

If you can or want, what is your thoughts about that prerotator ?
no torque ? no tip jets ? a ducted or oriented airflow ?

tip jets are not efficient for a fullpowered rotor, but maybe we could give them a try (i will), mounting a compressor is easier than an hydraulic pump+hydraulic motor (a common solution for prerotating). no torque, the rotor can have a residual power during flight.
yes, on this point i still not listen to what very valuable people tell me :} :rolleyes:
NB : the Groen Brs use ram tipjets to prerotate, 15 seconds are enough.
thank you

[widgeon]

I have found the Jet / Aim / Goodrich/L-3 Avionics range to be reliable and well priced Sperry/AlliedSignal/Honeywell are a little more expensive . Thompson/thales/Eads are french . We were talking about attitiude / Directional gyros weren't we LOL ??
Actually the Thales one probably cost about the same as a low end Autogyro

[rotornut]

Gyros:

Bensen + McCulloch = :oh:

(My friend had one but fortunately he's still alive)

[zeeoo]

RotorNut,
what could be interesting is YOUR perception of the gyros.
Thanks

[Aesir]

I heard that the McCulloch engine usually used in the Bensen was actually an engine designed for target drones, only meant to be used once!

They were a constant headache, but had good power to weight ratio.

I suggest that you steer well clear of those old engine designs, however Autogyro´s with Rotax, Arrow or Subaru engines usually work out ok.

Its not the engine or the Gyrocopter that will be the cause of the crash, it will be a untrained or reckless pilot!

[zeeoo]

Aesir,
You have a large variety of engines available for gyros, from the samller rotax to a IO-360.
A lot of amateurs also fit skidoo, moto or small auto engines that work fine.
You're very right to say, the main cause of accident is the piloting, not the aircraft or the engine.
I should add that an engine out is not a problem in a gyro, a great safety feature.

I am curious about how an helicopter engineer could adress a small gyro design..
Thanks
Victor

[XT244]

Hallo Victor

In Switzerland is flying one Gyro only.
This Gyro ist hangered in Bex, in the western part of CH.
Owner is a member of the FOCA (Federal Office for Civil Aviation).
The registration is in France.
May be, I find a picture ......

Regards

[Genghis the Engineer]

I am curious about how an helicopter engineer could adress a small gyro design..
Classically by starting with a design code such as BCAR-T and then looking how to show compliance with it. It is after-all the reason for the design code.

G

[zeeoo]

XT244,
thanks for the imput, only one gyro in CH ?? a shame, with the backgrounds you have, a gyro would be , for shure, very pleasant to fly, and safe... i hope you enjoy your B47 BTW ;)

Gengis,
if i understand, BCAR-T is the equivelent of our UL regulation, isn't it ?
If this code is not favorable to gyros, maybe it is not the proper code for that category :confused: i don't know...:confused:
I aml currently reading it as i post..

edit : after a quick reading, it is an interesting doc, complete, restrictive but clear.. it looks like it has been made by helicopter eng :D
What do you think ? is it a good or bad thing to avoid "experimental" buildings ? amateurs out !

thanks

[rotornut]

Well, Aesir said it correctly. The McCulloch engine was powerful (90 hp, I think) but was indeed prone to failure. My friend had a number of failures, once landing in a parking lot next to a highrise. He was so nervous about flying with that engine that he never left the local airport which included a large grass infield. (The airport is located on an island with the lake on one side, Toronto on the other.)

However, in fairness to Bensen, I never heard him criticise the airframe itself. I understand Bensens are good machines and his seemed to be pretty solid.

Speaking of engines, my friend spoke very highly of a Volkswagen engine, which produced about 60 hp.. I've lost contact with him and I don't know if he ever replaced the McCulloch with one.

[zeeoo]

Rotornut,
the Mac engine are longer used as they have been. The actual engines offer is far better and reliable.

VW engines work very fine but they tend to disapear (heavy), in favour of the small rotax 2 stroke engines.

For example: take a rotax 670 skidoo engine, it is 105 HP for about 50-60 kgs, this engine is widely used in the hovercraft world and is powerfull, reliable, easy to overhaul. And there are many other engines available.

I see that when you think gyros, you stay in the Bensen idea.
In fact, all the atual frames and rotor designs come from dr Bensen , right.

Thanks

[Ian Corrigible]

Zeeoo,

Not sure about their 'adopted' SparrowHawk design, but on their turbine Hawk 4 gyroplane Groen Bros (http://www.groenbros.com/) actually use rotor pre-rotation to achieve a jump take-off. The use of tipjet-type designs at most small airfields would run the risk of a visit from the lynch mob of the local noise abatement society... :E


Cheers,
I/C

[zeeoo]

IC

right about the tip jets thing, in city local airpports it can be a problem, not talking about the difficulty to develop a such system.. but, indeed, it has an interest on flight satefy by giving the rotor a residual power (nothing to do with a full powered tip jet rotor such as the SO-DJINN).
The hydraulic prerotators seem actually the most efficient, but not usable in-flight.

About Groen bros. i stated that they used ram tip jets, but i was wrong, i have read it on a news but it maybe for one of their "projects". But he system has been tried on other rotorcrafts

the Fairy ROTODYNE was an amazing bird.. a shame it has not been developped further.

cheers

[ShyTorque]

Another advantage of Autogyros is that they don't generate anywhere near the amount of downwash that a similar sized heli does.

The Fairey Rotodyne was a beast well in advance of its time. I'm sure there is a lot of potential left in that concept, glad to see that Groen Bros might develop a similar aircraft one day.

One thought is that the tip-jet design might be improved with respect to noise pollution by using blade slots rather than a tubular jet (move more air but slower) and a modern, more powerful turbine driven aircraft could perhaps divert sufficient compressor air through the blade spar to power the rotor without combustion being necessary. The noisy "tip jets" could perhaps be retained as an emergency measure in the event of an engine failure so that an OEI landing could always be made to the hover. A very useful bonus of that method would be simple main blade de-icing.

That tilt-rotor thing suddenly looks far too complicated in comparison!

[zeeoo]

Shytorque !
did you spy me or what ??

i think exactly the same thing about tip jets :

1 - the nozzles must be a slot
2 - with new materials and some new types of nozzles (i have some ideas) , the noise could be lessen significantly
3 - it is a wonderful safety feature, and btw, should allow some hovering and jump take off... just imagine you can pilot a helicopter with a gyro license !
4 - yes i thought about de-icing also, i live in a cold country (not canada lol). a de-icing is very useful..and free with tip-jets.
5 - making a blade with tip-jet features is not really more complicated than a classical one ( i have plans)
6 - modern superchargers should allow enough pressure (airflow ?) to have a basic air generator if coupled to a piston engine (www.rotrex.com)

For a very light gyro, a 3 or 4 bladed rotor is possible at low cost/complication (dick degraw built one on his Gyrhino).
A small rotor with smaller blades sould be feasable with less mechanical constraints than a bigger one, playing with new composite and elastomeric materials.
Some will say the R&D costs will be to high...yes, talking for ONE prototype, but , even if the gyro market / helicopter is small, this improvement should fond a good echo.

check that : construction begins in january 2005.

http://zeeoo.free.fr/gyro/G1.jpg

cheers

[zeeoo]

Is anyone interessed in joining a reflexion group about gyro design ?
Thanks

[johnee]

From The Northern Echo 16th December2004
Man dies as gyrocopter crashes
A 61-YEAR-OLD veteran flier died yesterday after his gyrocopter crashed into woodland.
The man, named as Dave Chaplin, from Borrowby, near Thirsk, North Yorkshire, was pronounced dead at the scene.
His gyrocopter crashed shortly after taking off from the Yorkshire Gliding Club's airfield at Sutton Bank, near Thirsk.
It came down just before 2pm in woodland near the White Horse monument, which lies directly below the airfield.
The crash site could be accessed only on foot but, according to North Yorkshire Police, firefighters and paramedics were at the scene quickly following the accident.
It is not yet known what caused the craft to crash.
The site has been cordoned off by police, who continued their investigations last night. The Air Accident Information Branch has been informed of the crash.
Mr Chaplin, who was married with grown-up children, was a former chairman of the Yorkshire Gliding Club and worked at the Sutton Bank airfield.
He was well respected in gliding circles and officials from the region's clubs were last night in shock at the news of his death.
A spokesman for North Yorkshire Police said: "The crash site, which we understand can only be accessed on foot, has been cordoned off pending closer examination.
"There seems to be quite a few witnesses to the accident."
A spokeswoman for North Yorkshire Fire and Rescue said: "The gyrocopter had just taken off from the top of Sutton Bank and crashed into the trees at Hood Grange Wood."
Gyrocopters were made famous when one was used by James Bond in the film You Only Live Twice.

[Dave_Jackson]

Gyrocopter Beats Helicopter into Submission with Corollas Prerotor (http://www.synchrolite.com/1402.html) http://www.unicopter.com/Temporary/KnockedOut.gif




Who will pick up the pen (or the sword) and fight back?

[zeeoo]

Dave, this idea has one merit : it came from your brain :D
i cant comment that idea.... but i'm curious to see how it could be usefull.

[Thomas coupling]

zeeoo: what is a BO108?

Cran your post on the advantages of an auto over a helo, make me cringe. You cannot be serious?

[CRAN]

Thomas,

I understand your reaction. I guess you are picturing some of the current amateur, kit-built autogiro contraptions along side shiny new EC135's or A109's. That is certainly not what I meant and in that sense, of coarse my point doesn't stand up! However, if you look in detail at the aerodynamics of autogiros and the flight dynamics of autogiros then there are real benefits over conventional helicopters. The real problem is that in trying to harness all of these benefits you end up with a machine that is just as complex as a helicopter. This is the real problem because I just don't think that is worth it. If we are going to start looking to different configurations to make 'better' (read: faster, quieter & more cost effective) helicopters then I think the most fruitful approach is to look properly at co-axials and inter-meshers.

[Enter Dave, front-stage-left, on horseback, racing to the rescue... :E]

In reality I think that gyro's will only ever be 'fun' aircraft for the recreational enthusiast, for the reasons we have all discussed before.

Hope this helps
CRAN
:ok:

[zeeoo]

a BO108, i don't know.... a kind of something flying maybe ? or a kind of secret codename ?

comparing apples with apples : what were the real last "mass-production" gyros ? la cierva ? lioret ?, after that ? nothing.
The fact is that people, armies etc accepted that an helicopter is expensive..

yes the EC135 is a beautyful million dollars machine, for that price it'better be nice and not hugly, indeed.

I am not trying to say a bensen equals a EC135, i just say that a basic gyro may fly better (exepted for hovering) than a basic helicopter (kit helicopter for example) at 1/3 the price.

I'm also still thinking that using a EC135 for some one-crew or 2-crew missions is a bit costy and that the gyro has a place where the helicopter is not justified.

I feel that there is a kind of ostracy from the helicopter world.. i feel that a rotary machine MUST be complicated, expensive and, overall , Dave will agree : HARD TO FLY.

CRAN : with great respect for you : the gyro flew pretty well before helicopters and if they are recreationnal machines, that's because they are left to the recreationnal pilots NOT because they can't be something else.. and because no company had a better look at them. I feel this view will last some times...

One thing is shure : you can solo someone after some hours of good training on a gyro, can you do that with an helicopter ?

thanks

[airborne_artist]

Have a look at the excellent and fascinating post (http://www.pprune.org/forums/showthread.php?s=&postid=1725365#post1725365) from Milt, a very experienced Australian TP, who writes about his experience flying gyros in the 60's.

His final paragraph on the subject:

Gyro-copters continue to be built by small bands of enthusiasts. Airworthiness authorities continue to grapple with safety aspects and have little effect on a steady string of crashes, more often than not, having fatal consequences for the would be aviator.

[zeeoo]

Artist,
you forgot to quote the previous sentence :
"A few months later this gyro-copter and its owner came to fatal termination performing some manoeuvre outside of its ill-defined flight envelope."

Very interesting experience, i feel that it shows the positive aspects of gyro flying.
Now, if someone gets out the flight envelope, may it be in a gyro, a helicopter or a bicycle : he may crash !

You can't say a B47 is not safe because a lot of crop sprayers had severe crashes ... you just can say they were close to the flight enveloppe boundaries.

The post you link to also , IMO, calls to not let the gyro to the only "small bands of enthusiasts"

thanks you

[Dave_Jackson]

zeeoo,

I agree with CRAN. Gyro's are the rotorcraft of choice for the recreational few. This is because they are; inexpensive to buy, easy to build, simple to maintain, and exciting to fly. If the pure gyrocopter was competitive with the helicopter, there would be Carter and Groen Bros. products in the air, as we speak.


"One thing is sure : you can solo someone after some hours of good training on a gyro, can you do that with an helicopter ?"

In 1948 the symmetrical Kaman K-125 was flown by a housewife with only 2 hours of ground instruction and 36 minutes of dual instruction.

Dave

[zeeoo]

Dave,
i have read the Kaman story about that, do you mean she was soloed after 2 hours ? Can you solo every housewife after 2 hours ? it would be so nice.


"If the pure gyrocopter was competitive with the helicopter, there would be Carter and Groen Bros. products in the air, as we speak.
"
As far as i know, they are in the air.
i don't think carter and groen have the same means than Bell, Boeing, MDD and friends... have they ?
and, of course, helicopters manufacturers have no interest in developing a challenger to their main source of income....
BTW state depts buys proven solutions, not side-solutions, they are not really "pionneers".... if they were we could see a lot of coaxial or intermeshing rotors in the air, right ?

remember, in the automotive market, the electric engine was considered during a loooong long time as a chimaera... not speaking about the hybrid powers.
but now that there IS a need for that, mas production hybrid cars come in the market.
it is all about the MARKET and the psychological impressum.

i guess that if you were a buyer for a state dept. and i was a gyro manufacturer, i would have no chance to sell one just because, thinking like this, you wouldn't even give it a chance.

http://www.groenbros.com/
http://www.groenbros.com/archives/hawksnest/nest30.htm

from their sources : Direct Operating Costs (per hour) $158.72

[Dave_Jackson]

"do you mean she was soloed after 2 hours ? Can you solo every housewife after 2 hours ? it would be so nice."

Kinky. :eek:

[frostbite]

Never seemed to 'take off' (pardon the pun).

Is there some reason why such an apparently cheap and easy flying machine is not swarming round the skies?

[vincent van gogh]

Hello,

I think it's because there have been a lot of accidents with them.
If you push the stick to quick/fast forward the rotor stops.

regards Vincent

[Aesir]

If you push the stick to quick/fast forward the rotor stops

Uhh.. well in essence yes, well put.

I have some hours in gyro´s. They are great fun to fly but that big rotor windmilling creates a horrendous drag which costs power to overcome.

In some ways the gyro is the best and worst of both worlds. It has the simplicity of airplane and manueverability of the helicopter but it also is expensiver to run than airplane and slower but yet still does not do what a helicopter can do.

[frostbite]

Thanks for that chaps, explains a lot. I would never have thought they were gas-guzzlers, but thinking about it......

[tangovictor]

I think the other problem is, passenger insurance is required, however no one will insure you,

[rotornut]

And the McCulloch engine in the Bensen is notoriously unreliable.

[GyroSteve]

There are only 70 or so gyros operating inthe UK (ie they have a current permit to fly). Most are single seaters powered by 2-stroke Rotax engines (so the McCulloch thing is a red herring).

There are lots of reasons why they aren't more popular in the UK, for example:

You can't (as of today) purchase a factory built machine. You either have to build one yourself (eek!) or buy one used which someone else has built (double eek!)

They have a poor safety record. None of the aircraft flying up to now in the UK have been approved to any engineering standard, they are all old designs with approvals based on "service experience". As a result many have some undesirable handling characteristics which make them vulnerable to mishandling. The poor accident record has made our regulators nervous about approving new designs or changes to old ones, which makes it very expensive and time consuming. This discourages people form innovating or building modern, safe machines - so the existing problems are perpetuated.

Because demand is low (due partly to the lack of aircraft) most people have to travel a long way to get to an instructor - much further than to learn on microlights or fixed wing, so the bar is raised once again.

Gyro cost more than microlights - used single-seat gyros have typically be selling in the £7k to £10k range. For that money you could get a decent 2-seat flex wing.

The good nbews is that it's all starting to change. The Magni M16 (see earlier in the thread) is finally approaching approval, and the MT-03 (www.rotorsport.org (http://www.rotorsport.org)) has completed all its testing and is in the final throes of the approval process (mine is due any day now!). With safe factory built machines available gyros are likely to become much more popular, though they will always remain a niche. That said, the MT-03 was the second largest selling microlight in Germany last year, and seems to be very popular with pilots looking for something different.

So why do we fly them? Because they are huge, huge fun. They are manouverable, have a wide speed range, draw a crowd wherever you go and make a fantastic "woc-woc" noise as you pull "g" - what more could you want?

For more info take a look at the British Rotorcraft Association website www.gyroplanes.org (http://www.gyroplanes.org)

[gyromike]

Aesir,
Most of the drag seen by the current recreational gyros is induced drag.
Max L/D on an autorotating rotor occurs at ~35% of peripheral tip speed. My gyro rotor spins about 340 RPM, for a tip speed of 410 fps. Max L/D is about 143 fps, or 97 mph.

Above that, profile and parasitic rotor drag starts picking up.

Unfortunately due to my Bensen's (http://www.rotaryforum.com/forum/attachment.php?attachmentid=6192&d=1099717840)airframe drag, I can't even touch Max L/D . I top out at about 85 mph.

More streamilined machines could likely cruise at their most efficient rotor speed though. Andy Keech (http://www.littlewingwonder.com/index.html)routinely cruises above 90 mph in his Little Wing gyro (http://www.littlewingautogyro.com/).

The previously mentioned studies highlight the importance of thrustline-to-CG relationship, and gyro designs have been moving back in that direction. I say back because this was something that Cierva had figured out in the early days of autogyros, and is just being rediscovered.

My opinion on the poor safety record of the early Bensen gyros is that:

There were no dual trainers to get instruction in. You had to teach yourself.
Bensen did not incorporate a proper horizontal stabilizer in his design. Without a horizontal stab, the pilot can end up in a Pilot Induced Oscillation (PIO) because of the lag and overshoot inherent in a teetering rotor system, possibly unloading the rotors. Add in an offset thrustline and the machine can begin an unrecoverable tumble. The addition of a horizontal stab can tame quite a bit of thrust offset in addition to minimizing lag and overshoot.
My Bensen has one.


As for the later designs, many 'designers' just raised the mast and rotor, and slapped a Rotax on the back with it's larger diameter propeller.
Instant thrustline offset.
And usually no horizontal stabilizer was installed to counteract it, or to stabilize the airframe.

I have flown a couple of these types and they are a handful.

But this is what I am currently building:
http://www.rotorflightdynamicsinc.com
And they fly like they're supposed to.
That's actually me in the first picture on the main page.:ok:

[Graviman]

Gyromike,

Is there any advantage in autogyro of a 3-blade articulated or even rigid head rotor? This would get around many of the reduced-g control loss problems, and elastomeric bushes are widely available (ie cheap lead/lag hinges possible). I remember being told about an ex-Westlands guy doing some work at Bristol uni - but it may have only ever remained theory...

I'm also puzzled why a teetering gyro seems easier to fly than say an R22. Is this just due to the direct control system, or does less rotor mass help? I'm a fan of the '60s Lockheed gyro system, but am now wondering if there is some inherent advantage to being in permanent autorotation...

Mart

[gyromike]

Gyromike,
Is there any advantage in autogyro of a 3-blade articulated or even rigid head rotor? This would get around many of the reduced-g control loss problems, and elastomeric bushes are widely available (ie cheap lead/lag hinges possible). I remember being told about an ex-Westlands guy doing some work at Bristol uni - but it may have only ever remained theory...
I'm also puzzled why a teetering gyro seems easier to fly than say an R22. Is this just due to the direct control system, or does less rotor mass help? I'm a fan of the '60s Lockheed gyro system, but am now wondering if there is some inherent advantage to being in permanent autorotation...
Mart

Sure Mart.

A multi-bladed head would provide 'head moment' to be able to maintain attitude during low G events. There have been a few one-offs built over the years, also the McCulloch J2 and Air & Space 18A gyros.

The 2-bladed teetering systems are just simpler and less costly.
But it's not the rotors that are causing the problems. It's the unstable framework underneath.

Eliminate the thrustline offset, and use generous tail surfaces, and even 0 G events are a non-issue (provided you aren't flying into tornados and such).

If you use a a full-span vertical stabilizer in addition to the horizontal to help eliminate torque roll and slipstream yaw with power changes, you can reduce the dangers caused by unloading the rotors. During a momentary unloading of the rotors, the aircraft will continue to track into the relative wind while the rotors reload. The problems occur when you are using rotor thrust to counteract rolling and pitching forces caused by the unstable airframe.

The Dominator that I linked to above actually has a slightly low thrustline which will tend to raise the nose in a low G event, helping to reload the rotors.

[Graviman]

Serious thanks, Gyromike! This makes very good sense. Would there be any advantage in having vertical & horizontal stabilisers as part of the control system? This just gives pilot an additional level of reduced g control.

I guess blade strike is never going to be an issue since you are directly controling rotor disk attitude. I imagine this has a slight reduction in response delay over teetering too. The real advantage is there is not going to be any complication due to flapback, the compensation for which is why teetering machines end up being so sensitive.

How do you find the cyclic forces with direct rotor control though? Would it be fair to comment that an equivalent teetering gyro could out manouvre a teetering heli?

Mart

[GyroSteve]

For anyone who's interested in autogyros the BRA Wallis Days event at Shipdham on 12th & 13th August is the place to go.

More details on www.gyroplanes.org (http://www.gyroplanes.org)

Hope to see you there.

[Heliport]

Is the legendary Wg Cdr Ken Wallis still flying?
He must be in his late 80s now.
http://img.photobucket.com/albums/v140/Rotorheads/Gallery/Wallis_LittleNellie.jpg
I feel old.
I was at school when he was Bond's double in http://img.photobucket.com/albums/v140/Rotorheads/Gallery/best.jpg

[SASless]

While a Civil Air Patrol cadet growing up....we had gyrocopters about the squadron grounds. The training copter was sat on a platform built on the rear of a pickup truck and secured loosely by chains so the aircraft could rise about a foot off the platform as the pickup truck drove down the taxiway providing the wind to drive the rotor.

The trick was to keep the copter centered over the platform while motoring down the taxiway.

Small bit of info was left out of the two minute brief by the instructor....that being "don't pull against the chains!"

Two of us nubbins strapped in and had our first gyrocopter training flight....each teaching the other.

About halfway down the trail....we managed to slightly overstress the rotor blades to the extent that one went walkies quite suddenly and without not much fanfare. The remaining blade opened up a huge can of whoop ass and spilled it all over the two of us, the pickup and anything within striking distance.

No broken bones but the pickup definitely had seen better days, the copter was a write off and we two budding aviators looked like we had each gone a dozen rounds with Mike Tyson, Mo Ali, Cutworm Smith, and a couple of other thugs.

That one "flight" cured me of gyrocopters.

Later as an instructor, when asked by a gyrocopter pilot to sign off a Biennial Flight Review, I would very politely but firmly tell them, not only would I not....but I would deny ever having met him.

[GyroSteve]

Ken was 90 earlier this year, and went flying on his brithday!

[Graviman]

Small bit of info was left out of the two minute brief by the instructor....that being "don't pull against the chains!"

I'm amazed they didn't fit a weak link on the chain.

Mart

[twistair]

For those with good connection this may be interesting to see: low-altitude piloting in our new open frame 2-seat tandem named "Twist" at sea shore.
Video (63 Mb of *.mpeg video) is here:
http://www.epilator.ru/trocadrive2.mpg

Aircraft itself can be seen in details at http://www.rotorcraft.ru

Cheers,

[rufus.t.firefly]

Nice video , well done !!!:D

[GyroSteve]

Nice vid - but the soundtrack on the vid on www.rotorsport.org (http://www.rotorsport.org) (follow the "Video" link) out-cheezes yours by an order of magnitude!

[Hebridean Jocky]

Hello there,
I would be grateful for any information at all on Autogyro's.
Recommendations for tuition and schools and also personal experiences would help.
Also looking for information from people that have their own machines. What would you recommend?
Is it possible to use a school's machine to do your solo work or do you have to have your own machine already by then?
I already have a PPL fixed wing but the spinning rotors fascinate me.
Thanks in advance for taking the time to reply.

Cheers

HJ

[Ian Corrigible]

A good resource is The Rotary Wing Forum (http://www.rotaryforum.com/forum/).

I/C

[Whirlybird]

I did a trial lesson and a bit more - about an hour and a half total - in gyrocopters some years back. I thought they might be a cheaper alternative for a helicopter addict...but I decided they wouldn't do and went for my CPL(H) instead. They are, however, great fun - a mixture of f/w and rotary flying that I really enjoyed.

If you do a search you'll probably find more up-to-date info than I can give. Back then, there were only 7 instructors in the UK. I went to Roger Savage at Carlisle. I wasn't impressed, but that was mainly for personal reasons; he virtually asked me if my husband knew I was out, and implied that as a mere woman I couldn't possibly have earned enough money to pay for my own flying!!! I decided I couldn't learn from someone like that.

There is a chap somewhere in the South-West who has his own machine and own website who was incredibly helpful, as are all the (tiny) gyrocopter community, in my extremely limited experience. Again, Google can probably help.

You might want to note that gyrocopters don't have a good safety record. Most people think that this is due to lack of regulation in the past, but no-one is certain. And engineering types who know far more than I do about such things say not to touch the extremely pretty RAF 200 with a bargepole - definite stability problems, I believe.

Hopefully you'll get some more definite info soon.

[BRASSEMUP]

http://www.pal-v.com/

A friend of mine holds a license for gyro's i'll have a chat with him and get back to you........

Wish i had the money for the carver pal-v.:E

[Barshifter]

Heres a few to go at other than the ones already mentioned.

http://www.gyrotraining.com/uk.htm

Ive met Steve Boxall on a handfull of occasions and hes a nice chap.Hes flying the latest German Two seat trainer now.It might be worthwhile giving him a call or view his website here.
http://www.gyrotraining.co.uk/

[bladegrabber]

HJ

I flew gyro's for 10 years and know a bit about them so if you send me an email i can answer your questions.

Generally good fun to fly but like all flying machines they have a few traps which catch out the uninitiated and people who don't train properly. There are a few schools around which offer dual, followed by solo instruction and i can give you my own opinion about who not to go and spend your money with.

[Hebridean Jocky]

Thanks very much to everyone for their advice.
I have done all the usual searches that you do when you get the bit between the teeth.
Personal opinion always wins though and there is no substitute for experience, even if it does belong to someone else.

Cheers
HJ

[GyroSteve]

A good place for some info on autogyros is the Britsh Rotorcraft Association website www.gyroplanes.org (http://www.gyroplanes.org)

There's a list of gyro instructors on there.

If you are after a factory built machine rather than a homebuilt, the only one available at the moment is the MT-03, from www.rotorsport.org (http://www.rotorsport.org)

There are kits available from www.layzellgyroplanes.com (http://www.layzellgyroplanes.com) and www.gyrocopters.co.uk (http://www.gyrocopters.co.uk) . The challenge with single seaters is learning how to fly them (!), which isn't helped by the fact that there are only a couple of instructors who will teach single-seat.

[500e]

Emergency MPD 2011-001-E: Magni M24C gyroplanes: Flight Controls - Rudder Pedal Mounting Block ? Replacement | Publications | CAA (http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode=detail&id=4433)
Emergency AD

[Paul Lederman]

Trying to outline design an auto-totary craft concept, was saddened to be reminded of poor safety record in fairly recent years though a little better more recently; the thread is most helpful in identifying main causes especially coincidence between both statistical and inherent causes thank posts for technical explanations. Yet I believe that when oiriginal Cierva autogiros and derivatives were conceived and developed throughout the 1930's they had better safety record than GA then. It had all been about avoiding fixed wing stall, before powered autogyros became helicopters.

[Helinut]

Paul,

It depends what code the thing is designed to. In the UK the CAA have done a great job developing a code for light gyros. This is the one that all manufactured gyros for UK registration have to comply with - known as BCAR Section T (CAP 643). There is a new version of Sect T published last year.

If you want to get into design of gyros, it is essential reading.

Like any aircraft, good training is essential, but that is not design

[Paul Lederman]

Very belated thanks "Helinut" for most helpful, necessary, advice re CAA code on autogyro design from which I have been learning applicable details. Ultimately I understand that safety will derive from pilot training and skill, but I believe that design of aircraft has to contribute. Even in the CAA specifications it does at least twice refer to activation of a control and its effect should be within capability of an average pilot of average strength. Also they have identified a past cause of accidents where starting procedure was wholly or partly initiated outside the craft; such that now mandatory for design to accomodate pilot in place from start.

[Paul Lederman]

"ZEEO" seems among the most positive regarding autorotary craft, but I can't generate link demonstrating manoeuvrability in TV film. I believe the remaining risks can yet be overcome to make them inhrerently safest as they once were. Paul Lederman

[heli1]

Any one reading this who knows about kit built Cricket production?