A better R22/R44 ?

[headsethair]

Amongst ppruners it seems to be a love or hate thing - the Robinson. Next year sees the 25th anniversary of the R22. Some my cheer - some may boo.
Could you design and build a better machine with similar capital and DOC ? Some of the Robinson's most vocal critics on this forum appear to be high-time professionals who must have some worthy ideas. (It's also worth noting just how many critics have never flown a Robinson!).
So, boys 'n' girls, can you outflank Frank ?

[Lu Zuckerman]

Keep the existing design but change the rotorhead to a three-blade head similar to the H-300.

With that simple change flapping extremes go away, rotor incursion goes away, mast bumping goes away, zero G goes away and best of all Lu Zuckerman goes away because with the change there is nothing to criticize.

:rolleyes:

[Dantruck]

Could anyone design and build a better R22 machine? Possibly.

Could anyone sell said machine in large enough numbers to sustain commercial viability? Almost certainly not...not when someone else - in this case Robinson - occupies the private and ab initio training market so substantially.

That was the gap in the market that really assured Frank's future, and led on to things like the R44, further growth, the refurbishment business he enjoys, the big revenue generating parts business, etc.

Nice idea, though...

Now, where's my sliderule?

Dantruck

[handyandyuk]

Idle curiousity here.... but you get 3rd party manufacturers offering alternate parts for exsisting airframes... prime example... the new blades for the 61.... so what would there be to stop someone coming up with a 3 bladed head for the robbos? Granted, they'd be looking at some serious cash and several years work.... but surely if it made a significant advance to an already popular airframe then would it not be worth the investment?

Mind you... short of the old favourite... 2 blades fit in the garage... 3 don't... who's to say Uncle Frank isn't already thinking in that direction? There's so much talk of slinging maybe a turbine... maybe a diesel... in a new airframe... so is the idea of a developed rotor system so far out there ?

And before someone starts taking shots... I openly admit I'm only a low timer (about 80) all on 22... I can't even afford 1 hour SFH right now, so I keep my nose in here to stay with it. I've not got the hours, years and job experience of most of your guys..... this is why I ask questions... good chance I might learn something :D

[CRAN]

Many people have voiced opinions about the R22 and to a lesser degree about the R44. Some times these opinions are positive sometimes they are negative, but regardless they are allways strongly held. I have often wondered about peoples perception as to what the REAL problem with Robinson helicopters is, some of our contributors would say its the light-weight two-blade teetering rotor system, [with or without 18-degrees of d3 :E :E] others will complain about lack of payload, speed, crashworthiness, cabin space, the t-bar system, the list goes on....

However, virtually all of the R22's [and in general the R44's] characteristics/vices can be be traced to one simple problem and in understanding this problem we can really marvel at the technical excellence demostrated by Frank Robinson.

The problem with the design of the R22 [and the R44] is this: THE ENGINE IS TOO HEAVY.

Taking the R22 as a case in point: the R22 has an empty weight of 389kg, the Lycoming O-360-J2A, installed in the R22 has a dry weight of 120kg this is 30% (a whole third!!!!) of the empty weight of the helicopter!

With this much of the weight budget invested in carrying de-rated engine mass around then very little is available for the airframe. Hence, Robinson was forced to compromise on the weight available for other components and payload. This requirement led to the use of the lightest possible rotor system, only two blades and no additional dead-weight [read inertia]. There was no weight avaialble for crumple structures or robust under carriage. Nor was there any weight available for toughening the airframe against fatigue and wear substantially, hence the relatively short lives of many of the compoents compaired to larger machines.

Robinson solved the key problem of of small helicopters of that time (Hughes 269 and Enstrom F28) which was the poor relability of there over-taxed engines, but in doing so created additional difficulties for himself.

The key point in this post however, is that he did a remarkable job of balancing the requirements and created a new industry in doing so. The R22 is very close to the best that can be done, if you want to achieve cost effectiveness and reliability with a Lycoming type engine. Yes a light helicopter with robinson reliability could be designed with a higher inertia rotor system - but you would carry less payload, or have parts to replace after only 1000hrs. As Nick says; 'There's no free lunch.'

Simply stated, the problem that faces light helicopter designers is not a helicopter technology problem, as there is certainly a large gap between light helicopters and bigger helicopters in terms of performance and safety [i'm NOT refering to engine failure rates here Frank!] the problem is engine-technology....or lack of!

The helicopter is one of the most demanding applications for torque-producing enignes. Helicopters have very strict requirements on power-to-weight ratio's as an extra kilogram of engine is a kilogram of payload that cannot be carried. In addition helicopters (single engined one's at least) operate at high power setting virtually all of the time.

With this in mind what Robinson has done is to raise the bar somewhat because if someone is going to design the next generation light training helicopter and entry level commerical helicopter that addresses all of the short comings of the R22, while simulataneously reducing the direct operating cost then you need a better engine. If you don't then you may improve one aspect, but another will suffer. A good example of this is the Guimbal Cabri G2, a french designed light helicopter that appears to be lost somewhere in the certification process at the moment. Lycoming powered, composite fuselage and 3-bladed elastomeric MR with a relatively good aerodynamic design. This aircraft will fly faster than R22, but will cost more and still have painfully limited payload. Will it sell.......we will have to wait and see but my guess is no....it'll be another Enstrom/Schweizer becuase in the training and entry level markets cost-is-king!

What do I think of Frank Robinson & his achievements?

Remarkable. Truely.
The R22 is a fantastic machine and the R44 is better. Robinson took an extremely difficult problem and has provided a compramise that is as close to the optimum as you can get when considering all apsects of a real helicopter. I would bet my mothers teeth on the fact that no-one designing a Lycoming powered helicopter will ever conquor robinsons market dominance.

I only have one real complaint about the way the R22 & R44 have been designed and that is that the tail rotor is too high. The R22 has a very low CG and when this is coupled with a high TR it causes the right roll in low-g flight to be exceptionally agressive. If the TR were on the CG centreline or closer to it then the R22 would not role so aggressively upon inadvertant entry into low-g. Once again this was a comprise - lower TR more tail strikes!

Could I design and build and better machine with similar capital and DOC?
Yes...

Have I ever flown Robinson's?
Yes, lots......i'm a big fan.

[slowrotor]

But the R22 was not designed as a trainer. The problem is this, there is no low cost purpose built trainer.
If Cran is correct in his opinion that the heavy engine is the major shortcoming of Franks R22, then the solution is a larger rotor diameter. A larger rotor would provide more lift per horsepower, a better autorotation and less twitchy cyclic. More suited to training. The only compromise would be slower cruise.
Since the R22 was not designed for training its hard to criticize the design as a trainer. But since the helo is in fact the most popular trainer it should be criticized so that any student has full knowledge of this fact. I think the R22 is a delight to fly but with my present knowledge of the accident history I have no further plan to fly any R22.
The FAA certification process is a formidable hurdle for any newcomer wanting to build a trainer. The FAA has unwittingly granted Robinson a monopoly for trainers with a design not intended for training.

[Vfrpilotpb]

Whilst I was training in the R22 the CFI said "if you can fly the R22, then you will be able to fly any other helcopter", on thinking about this, thats rather like saying the same about bicycles or cars, but in true fact the R22 makes your reactions so quick that you need to chill a little when flying other larger types.

The R22 is a good machine, it has its shortcommings but a lot of flying hours have been put through this small helicopter, if it could grow a little, say to the size just bellow the R44, with a better head, a proper stick system and a greater load capacity( people+ golf sticks), a small turbine and a lower CG, then it would be great, until then I fear that we will still see the sad end to some unwary flyers, due to small componants giving up whilst in use.

These are just my thoughts, but it seems strange for the authorities in BOTH the US and Europe to accept training schools using the R22 when the owner of the design always states after any training accident, The R22 Helicopter is not a trainer!!

Thats like saying cars are not made to transport passengers and luggage.:confused:

[RDRickster]

It's funny that it wasn't designed to be a trainer; however, every U.S. dealership is REQUIRED to be a training center by Robinson. Perhaps that is Frank's efforts to ensure proper instruction on an aircraft that was meant for personal transportation.

I just flew a B47G2 the other day - this first helicopter I've touched outside the R22. Next, I plan to fly the B2B, Enstrom, and 300 for comparison. Anyway, it felt like I went from a Volkswagon to a Cadillac! I'm glad I learned on the R22, because the belief that "if you can fly a Robbie - you can fly anything" was put into practice successfully (this time). However, I've definately been spoiled by the Governor.

It took me a while to listen to the engine closely enough and to adjust rpm manually. As a result, my first normal approach sucked because I failed to manage my power properly (she's a pig in a hover when the rpm is at the bottom of the green instead of the top). After I got more practice, it wasn't too bad. Also, I learned not to over control the cyclic; therefore, I really enjoyed the flight.

Maybe all the PPRuNer's should chip in a few bucks for CRAN and let him have a go at it. Maybe he can come up with something after all! :D

[Dave_Jackson]

This may be a very stupid or naive question, but it is a sincere question.

If it is true that there are already too many new pilots chasing after too few jobs, what purpose would a better trainer serve?

[ShyTorque]

CRAN mentioned the heavyweight engine in the Robbo.

I think (and hope) it's only a matter of time before we see a small helicopter powered by a modern diesel engine, running on Jet Fuel.

This type of engine has got many advantages over the old (nay, ancient) technology, 4 stroke AVGAS engine, one of them being a reduction in weight.

Another advantage is far superior fuel economy on far cheaper fuel (+-35% of the cost of AVGAS).

NO possibility of carb icing either (no carb or venturi).

No possibility of magneto failure (no magnetos).

No mixture control to worry about.

Need I say more?

:ok:

[slowrotor]

Dave,
Most airplane pilot certificate holders do not fly for hire. They fly for fun or business or sometimes just get a pilot certificate and never fly again.
For helicopters the cost per hour at around $200US probably limits the number of pilots that just like to add ratings for fun. But there are a few,and there would be many more if a low cost trainer were available. A good trainer would be purchased by most of the new pilots for private use.
So what the world needs is a good trainer that also looks cute enough for someone to own and be proud of.
The R22 was apparently designed for highly experienced pilots that enjoy the responsive control. The Pitts Special is a highly responsive airplane and experienced owners just love it. But a new pilot would say the Pitts is way too sensitive and I would not recommend learning to fly in a two seat Pitts,but it could be done.If the Pitts special was the only two seater certified for hire then surely flight schools would train in the twitchy little biplane and a lot of pilots would give up after the first flight.
Cessna sold C-150 trainers at a low price to get future customers for bigger planes with a higher profit margin. That may be foolish today because of liability, only a startup company would sell a trainer today.

[Dave_Jackson]

Slowrotor,

I agree with your points, and this is the reason for asking the original question.

It appears to me, that the primary need is for lower cost, safer and easier to fly helicopters. Then, and only then, will the need for a better training helicopter come about. Perhaps a new helicopter may satisfy both objectives, but I suspect that any need for an improved training helicopter will only be seriously considered when there are stronger incentives for people to get their licence.

[t'aint natural]

I think it would be very difficult to create a safer trainer than the R22 that was at all pragmatic.
Slowrotor announces that because of his knowledge of R22 accidents he refuses to fly them any more. What knowledge is that, mate? Here in the UK the R22 flies almost half of all single-engine helicopter hours. It's whacked about by cack-handed students and low time pilots going through manoeuvres you'll rarely encounter in day to day flight, and does it have half of all accidents? Nowhere near.
Perhaps you'd fly the 300 instead. But the Hughes has had at least nine fatal mid-air break-ups due to a design fault which has still not been corrected on the first 500-plus machines. Imagine what you'd be reading from the Robinson-haters here if the same could be said for the R22.
Yes, we could all be like the UK military and do our ab initio training on AS350s. Trouble is, that would kill the industry stone dead.

[slowrotor]

t'aint,

"Slowrotor announces that because of his knowledge of R22 accidents he refuses to fly them any more. What knowledge is that, mate?"

I said with my present knowledge of the R22 accident history I have no further plans to fly a R22. That could change if I receive enough information to explain what has been done to correct the problems that caused the rotorhead separations.

The knowledge I base my choice on is primarily the NTSB special report for the Robinson R22. Go to ntsb.gov and search for Robinson special report.
Specifically the report states that the R22 accident statistics are about 4 fatal crashes per 100,000 hrs. The other helos were more in the 1 fatal per 100,000 hrs as I recall, the 300 was much better than the R22 but I cant remember the exact data, look at the actual report if you have not already. This data is per 100,000 hrs so the fact that R22's are prolific is not relevent.
Further,I read through many of the non-fatal ntsb reports from 1970's to 2003. Again, as I recall something like 350 of the 800 USA R22's have had an accident.

I was about ready to buy a used R22, but my reseach has put that on hold.
The FAA issued an airworthiness directive to limit flight in moderate turbulence.
The FAA issued a special FAR 73 just for the R22 that requires special training.
A CFI told me to ask local R22 owners about these facts. I tried that, and the local owner became very abusive when I asked how to avoid the rotor separation, the cause of which is not all that clear to me at this time.
I asked an FAA engineer what is it with the R22 and he said go to www.pprune. rotorheads.
Here I am.

slowrotor

P.S. Just checked the NTSB data base and it pulled up 297 R22 accident reports for USA. I get a different number depending on the particular search but in general the accident rate is very high. Sure, it's usually pilot error, I want to know about that as well so I can avoid the result.
Just reread the NTSB R22 special report and it lists 850 USA R22's in use instead of the 800 I listed above from memory. That was 1996.
Some accidents are not reported to the NTSB.

[headsethair]

Slow rotor : " Again, as I recall something like 350 of the 800 USA R22's have had an accident."

You may be asked to verify that figure. IMHO, it just isn't true.

[Lu Zuckerman]

To: tain't natural

Stop being so defensive. The NTSB report was generated sometimes in 1994 and published in 1995 and it was primarily addressing somewhere around 27 loss of control accidents involving the R-22. In that report comparisons between several helicopter types are made including the H-300 and the comparison was as to the accident rate and not loss of control or rotor incursion or mast separation. It may be true that 5 H-300s have crashed due to a faulty cluster weld assembly but the problem has been addressed and it should not happen again if the weld assembly has been replaced or properly welded.

In one NTSB report on an H-300 crash not related to a cluster weld failure they indicated that there was severe corrosion inside the cluster weld assembly. Maybe this problem should also be addressed.

Since the NTSB report was issued and the SFAR was promulgated there has been two loss of control accidents in the UK, one in Ireland, one in South America and one in the USA for a total of over 31 accidents due to loss of control. Aside from the SFAR there have been flight restrictions placed on the Robinson helicopters and still these accidents continue to occur.

One word comes to mind. Rotorhead.


:E

[The Nr Fairy]

Fine. Since 1994 there have been 3 more fatal accidents due to rotorhead separation. Lots more due to wirestrikes, not getting the lever down after engine failure, and so on and so on.

It's not the aircraft, it's the education (or lack of it) or ability (or lack of it) of the pilots. That's the same for any aircraft.

And the H300 cluster weld design falls in a different league, as far as I'm concerned.

[headsethair]

Can only assume that doing a better job than Frank is nigh on impossible - other than redesigning the rotorhead (!) or maybe using a 3-blade rotor. That seems to be the message so far.
For non-USA I would suggest that the lightweight diesel/Jet A1 engine comes asap. But there's the rub - the USA market isn't feeling too much of a pinch on the use of Avgas and Frank's favo(u)rite US dealers aren't shouting "gimme a diesel!"
Which p***es me off everytime I spend $150 filling an R44.

[t'aint natural]

Here we go again...

Where's my Z22, Lu? I'm still first on the wait list, right?

Slowrotor: Don't get hung up on ten-year-old statistics. Start by reading the roughly one million threads that have dissected this issue on the forum, until even I'm starting to tire of them.

[SFHeliguy]

OK,

So I'm not usually much at posting stuff but here's my 2 cents:

I'm a 300 hour fixed and 80 hour R22 pilot . The only time that I've ever logged in something with the big spinny thing on the top is in Robinsons. So, I don't notice the sensitivity as it's all I've ever known.

I went to the factory course and was very impressed with the quality of the mfg enviornment and processing.

I'm now a R44 owner and have every confidence that for the money, I've bought the best heli available.

And yes, if it had 3 blades, I'd have to consider a Jet Ranger because my hanger isn't big enough.

[Dave_Jackson]

Earlier in this thread, there was discussion about the Robinson engine and the advantage of having a lighter one.

Perhaps Robinson is considering the new Bombardier V-6 aero engine. A 220hp, normally-aspirated version, and a 300hp turbo. Bombardier claims, "...the best power-to-weight ratio in aviation technology.". There has also been mention of 2,000 TBO and FADEC

[Vfrpilotpb]

I am sorry if this is drifting a little off the actual thread but, can anyone explain this,

FR makes great play on the point that the R22 is NOT designed, built or supplied with, or for any sort of training purpose, now if this is expanded a little, Why do FTO's use the R22 as a basic trainer, expanded this little more,( this has to be lateral thought) we are informed of quite a lot of accidents and sad fatalities in connection with the ubiquitous little heli being used by student and low timers, the aftermath is always picked up and sorted out by the companies who insure the FTO's, is there not some conflict here,... Ie, FR says Not a Trainer, but XYZ insureres cover the heli for training! where and who holds the Duty of care, that provides this ability and permission to use this R22 type to train new pilots.

If the R22 in my opinion is going to be used to train people, and is accepted by insurers as safe to do so, then why does FR try to steer away from this point! what does this gain him?

Peter R-B

[Lu Zuckerman]

To: Vfrpilotpb

If the R22 in my opinion is going to be used to train people, and is accepted by insurers as safe to do so, then why does FR try to steer away from this point! what does this gain him?

It gives him a sort of absolution while placing the blame on the pilots’ actions while not addressing the real problem, which is the design. (Read Rotorhead).

:E

[3top]

Hi all,

if you say "Loss of control", do you mean loss of control by the pilot, like in flying into bad weather, clouds, getting all worked up and loosing it or freezing on the controls (saw that too...) or loss of control due to mechanical failure like mechanically frozen controls, blade/rotor separation, etc.
Note: I do not consider a Tail boom separation after a pilot error a mechanical loss of control. In this case the pilot lost it long before!

That Robinson requires every dealership to be a training center is logic. If you sell a machine that is generally sensitive, you want to make sure that the future owner is able to handle it. I understand that any Helicopter dealer would provide transition training to their product. Robinson doesn´t say, that you have to have a flight school for initial and advanced helicopter training.
I understand Training Center refers to Robinson transitions, aircraft ground handling, etc.

He would be nuts if he allowed anyone to sell his aircraft without providing that training!

All I wish for would be a passiv electric trim system in the R-22. Getting old and wishing for more comfort!

AND more emphasis on correct handling of the R-22 by schools, incl. respect for the limits published, like weight!!

Cheers,
3top:cool:

[Shawn Coyle]

Some one asked at the very beginning what they would do to improve the Robinson line?
The only two things that come to mind as anywhere near 'essential' are a 'normal' type of cyclic, and change the engine and rotor RPM gages to something like the rest of the world uses - the crossing needles must take a considerable amount of time to get used to.

Did anyone ever consider a hub spring, as was done for the AH-1Cobras - I know this would transfer the problem somewhere else, like the top of the transmission, but it might be worth considering.
A good simulator at low cost would help a lot - the Fly-it one comes close but could stand more tweaking.

[Lu Zuckerman]

To: 3Top


QUOTE: That Robinson requires every dealership to be a training center is logic. If you sell a machine that is generally sensitive, you want to make sure that the future owner is able to handle it. I understand that any Helicopter dealer would provide transition training to their product. Robinson doesn´t say, that you have to have a flight school for initial and advanced helicopter training.

RESPONSE; If this is the case then why does Frank Robinson state that it was not designed as a training helicopter whenever there is a fatal crash? Especially, if it involves loss of control.

To: Shawn Coyle

When Bell upgraded some AH-1 series helicopters they went from steel bearings on the teeter trunnion to Elastomeric bearings. I do not believe these bearings would qualify as hub springs. However on the AH-63 that competed against the Apache the rotorhead had elastomeric bearings that had such high resistance to torque (teeter) that they qualified as hub springs.


:E

[Dave_Jackson]

Shawn,

The Good ~ A hub spring will assist in keeping the rotor disk normal to the mast. This is especially beneficial when the disk is unloaded.

The Bad: ~ If the helicopter has only two blades, a 2/rev. vibration will be created. when the disk is tilted.

More information on Hub Spring (http://www.unicopter.com/1230.html)


Lu,

Here's a little thought provoker for you. ;)

Rotors will resist negative coning to some extent because the lowest collective pitch on most is approximately plus 1-degree. Even this small amount of positive pitch should oppose negative coning. An exception to this would be when the craft was subjected to negative G's, which resulted in a collective negative angle of attack.

In addition;

The offset flapping hinge rotors will resist negative coning because of their offset flapping hinge and the centrifugal force on the blades.

The teetering hinge rotors have a pre-cone of 2 to 3-degrees in the hub. This combined with the structural strength of the blades will help resistance negative coning.

An exception to this might be the Robinson. It does not have an effective offset flapping hinge nor does it have a structural pre-cone. :E ;)

[Lu Zuckerman]

To: Dave Jackson

An exception to this might be the Robinson. It does not have an effective offset flapping hinge nor does it have a structural pre-cone.

Dave I don't know if I completely follow you. Not because of you, but because of me. After all, I am an old man.

The Robinson can not achieve a negative cone as the blade can not pass through its' static or radial position. The downward movement of the blade about the cone hinge is restricted due to the spindle tusk making contact on the droop stop.

It is this element of the design that can cause problems. Any force mainly flapping excessively will cause the spindle tusk to strike the droop stop and result in the spindle tusk fracturing and the blade is then free to make contact on the fuselage.

This same phenomenon can result in mast bumping if the contact force is strong enough and the tusk does not fracture.


:E

[Dave_Jackson]

Lu,

Your correct about the spindle tusk. I forgot that the Robinson has static droop stops, and not dynamic ones that move out of the way.

The same concern still applies though. It appears that the Robinson hub may be more inclined to want to go into negative coning than do conventional teetering hubs (with their pre-cone) and fully articulated hubs (with their blades' desire to align with the mast plane).


While trying to provoke a fight with someone, I might as well pick on Prouty, also. :O

Prouty says; " On his R22, Frank Robinson has installed separate blade flapping hinges in addition to the hub teetering hinge. This achieves the same result as the Bell flex-beam while reducing blade-root bending moments ...."

It appears that the Bell 412 flex-beam hub has virtual flapping hinges. These flapping hinges must be offset from the center of the rotor. Therefor this 'offset' should result in the rotor acting more like a conventional fully articulated rotor than the Robinson's tri-hinge rotor.

:E :E

[Lu Zuckerman]

To: Dave Jackson

It appears that the Bell 412 flex-beam hub has virtual flapping hinges. These flapping hinges must be offset from the center of the rotor. Therefor this 'offset' should result in the rotor acting more like a conventional fully articulated rotor than the Robinson's tri-hinge rotor.

What you say about the 412-rotor system is true. Because there is a virtual flapping hinge the disc plane will vary from the pure radial position relative to the rotorhead and as such will lead and lag. To accommodate the lead and lag the rotor head is “soft in plane” which allows controlled leading and lagging.

On the Robinson head under ideal conditions the blades will maintain their coning angle relative to the head. However the aerodynamics of the head are such that the blades can as required flap on the cone hinges independent of each other. When the blades flap there is lead and lag. However the lead and lag is restrained and the forces generated are reacted mainly by the cone hinges ,the mast and the blade root.


:E

[Gaseous]

A better R22?

Enstrom almost did it but blew it (literally),when they bolted on a turbocharger in search of a real third seat. The original 28A has three fully articulated blades, lovely docile handling, and two up, performance very similar to R22. It cruises at 21", 2750 rpm and 80mph, so is not all that overstressed. It has a real stick and looks like it is finished! It has an exemplary safety record. Unlike Robbie, there has never been a fatality caused by mechanical failure. It has very few lifed componants. Even the main rotor blades are not lifed.

This seems to fill most of the desired criteria.

It is also too heavy, too thirsty and considered a pig to work on but it is a 40 year old design. There is considerable scope for lightening and improving it using modern materials and design techniques.

Enstrom turned out 100 plus aircraft a year until the turbo was added. Then they could only manage 10 or so. Had it been lightened and developed specifically as a 2 seat trainer it could have cornered the market. As it was, Enstrom effectively vacated the trainer market in the late 1970s in search of the 'executive' market, leaving a vacancy for Frank.

A turbine is always going to be too expensive for a basic trainer with an Allison 250 costing about 10 times as much as a Lycoming. Look how much a 480 costs which is basically a stretched version of the F28 with a turbine chucked in.:eek:

My beer mat design would be a 2 seater with Enstrom dynamics. A 230 BHP SMA flat four diesel would replace the Lycoming. Not too heavy. No Avgas. No 12 year rebuild and not underpowered or overworked. It would probably be costlier than an R22 unless built with cheap far east labour.

Maybe that's why Enstrom have started a new facility in Wuhan province, China.

Watch it, Frank!


I have more hours in R22s than Enstroms.
I own a lovely old F28A which I prefer to the R22.

[Decks]

Have one question... How many of the so called loss of control accidents have occured in the R44... apart from the original in El Monte??? (Very few I bet.)
Have been out of Robinsons for years but the debate has become like a skipping cd. Have about a thousand hours in the R22 and the same in the 300 (all instructing)... I have to say they are both great helicopters. If I was buying one for personal use, the R22 would win hands down.

[Robbo Jock]

Shawn,

With respect to the 'crossing needles'. To me, they are a great way to present the RPM information. (Admittedly, I've been looking at them since my first helicopter flight, so they would seem natural !) Reading them is, to me, instant and unambiguous. Crossed or split, it's easy to see on a scan and either ERPM or RRPM is easy to read.

Obviously, it's what one is used to - I've had a few hours in other aircraft during which I had great problems with the concentric presentation. I found myself actually having to look at and read the pointers & dial, rather than just being able to scan and assimilate. Silly, I know, but my mind kept posing the question: "am I looking at two pointers overlaid, or just the one ?"

[slowrotor]

Gaseous,

Could you give some more insights as an Enstrom owner, I will look into the possiblity of buying an older ship.
I have bought many older aircraft, damaged or out of annual for a low price then fixed them and did cosmetic repairs as I flew them, then sold them at a price that pretty much covered the cost of my ownership.
Might do that with an Enstrom.
What is the price range of old Enstroms?
What are the life components or other major costs?
How does the manufacturer treat you when ordering parts?

Thanks for any info you can provide.
slowrotor

[Gaseous]

Slowrotor,

Owning and operating an old Enstrom, for me has been a joy. I use it for fun, and fly mostly short hops to friends and local hotels. It lives in my garden with a full cover over it.

The non turbo 28A and 280 start at about £40k in flying condition.
The sort of approach of buying a tatty one and doing it up is exactly what I did and it now looks rather smart. I'll e-mail you a picture.

Insurance is cheap (compared with R22) as it is based on value. There is no problem with most mechanical parts as many F28A parts are still used on new aircraft. U.S. Dealers are good for new parts. There are a few scrap F28s about for the other bits.

Parts Lifed to scrap
TR flexpacks
TR gearset
TR spindle
MR shaft
assorted bearings
tacho drive belt

Parts Lifed to overhaul
Engine
mags
fuel injector
clutch
MR gearbox


All blades are 'on condition' - no life limit. Check for debonding. Repairs are acceptable. Good second hand main blades are about £1000 to £1500. Lamiflex head bearings are 5 year items (U.S.$3600 for the set). The main rotor shaft has 19000 hours life! ( how do they work that out??)

Find an engineer who likes them - many don't.

It uses 11-12 U.S. gallons per hour- Turbocharged aircraft carry more weight but the engines are overworked and never reach TBO of 1500hours. Consider a non turbo as a 2 seater plus very small child. Forget it for hot and high. Performance is similar to R22. Handling is docile but remember that Dennis Kenyon has used Enstroms for his stunning aerobatic displays. With the trim set carefully it will fly hands off for about 30 seconds. Try that in an R22! There is no governor and many have no correlator. This is not a problem, in fact it adds to the fun. Autorotation is undramatic.

As with all aircraft, especially old ones, get a survey done and be very careful!. Expect problems - if you don't get them, be very happy.

Gaseous