Ukrainian 2-seat helicopter

[slowrotor]

feedback

The quality overall looks outstanding.
The technical problems can only be found after extensive actual flight however and much specific testing by test pilots and ground based testing.

I would be concerned with the blade tension torsion pack. The flexing of the thin "feeler gauge" in bending from lead lag might kink them. I saw a similar kink on a helo in a museum. Maybe that was one reason it was in a museum.

Also, the engine is uprated if you will, as most auto engines are when they go flying. The R-22 engine is derated (or was in the first ship, I am not sure if they still call it derated with the current engine).
I think derating is the way to go for long life.
slowrotor

[Ian Corrigible]

Originally Posted by glyn thrash

why you think it would give the R22 a run for the money

Well, the timing's certainly right. Robinson has been moving to position the R44 over the R22 as its preferred solution for training, and its pricing strategy reflects this move away from the 2-seater.

I/C

[Graviman]

Originally Posted by Glyn Thrash

Mart, could you stress the point of the engine in this thread, also why you think it would give the R22 a run for the money. any idea's you have on the helicopter, and your thoughts over the whole design.

Glyn, i should comment that i consider myself very much a guest on this forum. I am a practising mechanical design engineer with a particular fondness for helicopters. While i have flown the R22 under instruction (at the moment it is really just too expensive for me to go further), i can only really make any judgement based on my engineering knowledge.

I get the impression that the strength and weakness in the R22 lies in the design of the teetering head. It is extremely reliable, and a very cost effective solution. At the same time it does not offer the same level of controlability as the Aerokopter laminated steel torsion bar bearingless design. This will help a student pilot gain confidence much sooner. A more experienced pilot should definately be consulted though.

My comments about gyro control refer to the experimental Lockheed CL475, which had a totally mechanical system which enabled a fix wing pilot to simply jump in and fly, with no helicopter training. The engineer who knew most about the practicalities of this system sadly recently passed away. The CL475 was overshadowed by the problems in the AH56 program which followed - specifically aeroflexure divergence from the cambered aerofoils required for high disk loading. I made a point of trying to understand Lu Zuckerman's wisdom on the subject in this forum, and interestingly the orginal CL475 system might be suited to the Aerokopter rotor head.

Engineering products coming from this region of the world have a reputation of being very well tested, and almost indestructible in design. From the pictures, i agree with Slowrotor about the outstanding quality of workmanship. I can't comment about the blade tension torsion pack, but can understand how extreme manouvres might cause the laminated steel torsion pack to lead/lag buckle (coriolis force). Perhaps if you were to provide information about the product development testing schedule or time accumulated by individual prototypes it would help others gain confidence in the machine reliability.

The Subaru engine familly have proven their automotive credentials in rallying (Finnrotor's comment below about duty cycle life expectancy is well heeded):

http://www.prodrive.com/default2.asp?M=450

I can find no reference to the EJ-25 specifically.

I was convinced that Diamond used a version of this engine in the Super Dimona:

http://www.diamond-air.at/en/product...ifications.htm

They seem to use Rotax now, so perhaps my memory is in error.

http://www.rotax-aircraft-engines.co...index?Openpage

I had wondered if this was a Subaru boxer dressed for aero applications, but it looks like a different unit to the EJ-25. It may be worth contacting them directly.

Mart

[Finnrotor.com]

The Subaru engine has proven it's automotive credentials in rallying:

http://www.prodrive.com/default2.asp?M=450
Although disappointingly i can find no reference to the EJ-25 specifically.

That's because it isn't the same engine...at all. That's a 2 liter, EJ-25 is 2,5. I don't think you can compare WRC engine and the ones that are used in aviation. World Rally Cars' engines are changed after every other weekend (max 1000km)...

[Ian Corrigible]

Originally Posted by Graviman

Although disappointingly i can find no reference to the EJ-25 specifically

The EJ25 is Subaru's 2.5L boxer 4 (300hp with turbointercooler, 180hp without). I have one in the garage - comes alive at 3500 rpm, growls at 6000rpm!

EJ25 conversions for homebuilts are already offered by a number of specialists, including NSI Propulsion Systems and Eggenfellner Aircraft.

I don’t know of any current helicopter apps, though Subaru's larger 3.0L 6cyl engine has one notable application: the Boeing A160 Hummingbird VUAS.

I/C

[Pandalet]

Out of curiosity, what sort of timescale are we looking at for JAA type approval, approximately? Can one fly a non-JAA approved helicopter in the UK?

[glyn thrash]

Out of curiosity, what sort of timescale are we looking at for JAA type approval, approximately? Can one fly a non-JAA approved helicopter in the UK?

all i can say about that is that, there are works on getting it there. there are some around you that are flying.
what i would like to work towards is a full FAA certification with this heli. i believe that it will greatly change the small heli market. the engine is a MAJOR hurdle that has to be taken on. the quality of the kits are awesome and well worth it. but with out a cert. it's hard to sell. that is one of the reasons that the heli hasn't hit the US market yet. although another reason is that the factor is full up building for the next year or so. there are ALOT of orders coming in. great engine, and i have seen it in action on a small fixed wing.

thank you guys for the comments!!! feed back, good or bad, is what is needed to move. thanks again,
glyn

[corncrasher]

I would like to make a few comments about the engine. I worked in a subaru dealership and have factory subaru training and quite a lot of experince with there engines. As car engines go they are a good engine but in an aircraft I would have reservations such as the single coil pack which I have replaced quite a few in the cars. The dual mags, simple fuel system, and aircooled engine in an R22 I think are advantages.

[tangovictor]

agree

I agree with corn, the engine appears ideal and is used by many others appart fron cars, Re the FAA, I don't live in the US, but would have thought it wouldnt be that much of a problem, with reguard to all the other "experimental" types allowed to fly there, which would stand a snow balls chance in hell, here in the UK.
I wish the project well, and hope they go for and get JAA approval. there's a couple of Italian I think other small heli's which I believe are kits
I'd imagine the CAA wouldnt like those here either

[Ian Corrigible]

I stand corrected: there is at least one 'production' rotorcraft application that uses the EJ25 - the AAI Sparrowhawk.

I/C

[Graviman]

One thought worth bearing in mind is that automotive engine designers are perpetually under duress to improve exhaust emissions. Combine that, the expectation of better power to weight, and the production volumes in the automotive world means that any engine design will have a finite shelf life before it is succeeded by a newer design. I had wondered if that was why Diamond switched to Rotax (i'm sure they used to use Subaru).

There may be methods in the certification process that make it much easier to certify what will eventually become the EJ-25 replacement, by considering EJ-25 at this stage. The alternative is just to make sure of a stock of production/spare engines. Occasionaly engine life is extended by building under licence - this may well be justified for a good aero modified design.

Mart

[Aerokopter]

EJ25 - to be or not to be..

Hello guys,

This is very nice to see for all of us here, in Aerokopter, that our small bird gained your attention.
We are very young group of the companies, five years for the aviation market is very short period of time. We understand, that we should start from small and relatively simple things, making it safe and reliable first.

Yes, we know well, that we will not be able to certify AK1-3 in US with this engine, but at the same time we finish type certification process in Ukraine and it`s allowed to use this heli easier in Russia and the rest of ex-USSR countries (280 mln of peoples), this is also possible to get First-Type status in the South Africa and fly there, teh same is for few other countries.

This experience gives us a real chance to build the next heli...

This is too early to tell you something, but just to give you an idea, that Aerokopter`s team doesn`t waste time - we started to plan 5 seat heli with turboshaft engine (perhaps AI-450) made by famous "Motor sich" plant.
Our respected partners have English version of the web site, but unfortunately they don`t have english page for this engine - http://www.motorsich.com/rus/product...urboval/ai-450


Well, it`s a deep night in Kharkov.. see ya

Alex Miroshnichenko

Aerokopter-Trade, CEO
Kharkov, Ukraine

Email:

[email protected]

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1:23:39 AM

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[tangovictor]

congrats

Well done Alex
Great looking machine, if ever it were to be certified within the UK
I'm sure you would have quite a few customers,
Keep up you good work
TV

[Graviman]

I wish you and Aerokopter every success for the future, Alex. This machine is a very good design, but you are absolutely right to pace the introduction into the international market place. Few folks outside of engineering realise the absolute headaches involved in developing a product from clean sheet of paper, to consistently reliable production.

Mart

[CRAN]

An exceptional achievement guys, very well done.

Best Wishes for the future.

CRAN

[Aerokopter]

Good afternoon dear fellows,

Thanks so much for such nice words and wishes. We, at Aerokopter, are very shy, so please, .... stop to praise, start to lash.

And one of my personal biggest bewilderments is why during last three year nobody from US (except Mr. Sikorsky) came to Ukraine?

This is not so extremal, trust me or ask Mr. Albert Questiaux,who just sent me "SA Flyer" magazine with the his (third?) big article "First test report: Aerokopter Sanka".

You must come to feel Ukrainian hospitality, bad roads, make shashlik (bbq), drink a bit and make a demo flight (before drinking, of course..) !!!

Try not to promise me....

Yours Alex

[Pandalet]

Actually, I wouldn't mind a quick visit to the Ukraine...

Alex, could you give us some idea of who to contact to arrange visits, when the best times are, accomodation availability and (approx) costs in your area, etc?

Ta

P'let

[Efirmovich]

Privyet Alex !

I spend quite a lot of time in Ukraine, as I have a Business in Kherson.

Next time I am over would it be possible to visit your facility and look at your product ?

Do Svidanya,

E

[Finnrotor.com]

Yes, we know well, that we will not be able to certify AK1-3 in US with this engine

Mr Aerocopter,

And that's the same in Europe, i would quess... So why can't you put another (certified) engine in it?? You have developed an attractive product, built quite a few of them already so i would imagine that it wouldn't be that difficult to find another engine so that you would be able to certify Sanka in North America and Europe as well.

There's certainly a market for a new light (certified!) helicopter, not everybody are happy with R22's and S300's, which is designed just after the stoneage . You have a product, which have caught many people's attention already, so..

[Aerokopter]

Trip to Ukraine

Originally Posted by Pandalet

Alex, could you give us some idea of who to contact to arrange visits, when the best times are, accomodation availability and (approx) costs in your area, etc?

You can contact me directly when you decide to come and we will discuss everything. Someone likes to come during winter, someone - not, someone prefer to stay in the hotel ($50-75 per night), someone in the excellent rented flat ($50-90) and so on..

We will meet you in the airport, drive to the hotel, show the city, drive to the production plant and so on, so don`t worry.

Alex