Enstrom closes doors

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EzyBuildWing

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Cut and paste a picture of Heli into MS Paint. Then, in Paint, go to "Tools" and select "Colour picker" then click on any colour in your picture, and hey-presto, you can draw anything in that colour! Took about about 15 minutes to add the sail to Enstrom's mast.
Below, more artwork. Maybe if Enstrom mocked up a heli like shown below, and sat it beside an R-66 on the ramp and explained how the 10-second rotor-inertia difference makes Enstrom so-much safer, then it's a no-brainer going for Enstrom.

Enstrom Turbine Artwork Jan 2022.jpg
 

raytol

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Wow, I can't believe how much better it looks with a mast fairing! Makes it look stronger and faster! The fairing would weigh very little and right on the CofG, sometimes engineering has to give way to appearances ( car wheel nuts are a great example).
 

Martin W

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May 14, 2021
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.

Enstrom had a very good 3-blade rotor (a bit heavy) .... the rest of the machine was also somewhat overbuilt (strong but heavier) .... despite the extra weight those things are often desirable in hard working aircraft.

Problem was they started out using the 360 engine which is very happy turning out 180 hp .... but Enstrom had to turbocharge and boost it to eventually up to about 240 hp in order to perform and compete.

If they could have adapted the 435 engine (like the Bell 47) it would produce 250 hp all day long with power to spare.

Easy for me to say , but not easy to change powerplants in a certified production machine.

Light machines like R22 and Hughes 269 work great using the 360 ... Enstrom not so much.

.
 

TFF

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Enstrom stared with 205 horsepower naturally aspirated, went to 205 turbo, then to 225hp turbo. Naturally aspirated ones, which are my favorite, poop out at 6000 ft. You are not flying one in the mountains. 205 turbo had them juggle rotor RPM so it feels not as peppy as before but has altitude. 225hp is pretty good. The problem is weights went up with accoutrements, but there is a lot of weight in the rotor. That’s why it’s a beauty to auto. It makes you need to anticipate with more throttle or you will behind on the power curve. Learn it right and you will be a better pilot on every other helicopter.

To put being overbuilt, except for some minor differences due to time, the rotor system is the same from the 205 hp original to 300hp for the turbine. Only rpm that they are run at is different. Gearboxes are essentially the same They are tough. Their was a plan for a four seat piston in the late 70s, before the turbine. It would have used a 540 but the prototypes only had 360s. A turbine engine saves almost exactly one person’s weight over a piston. Free person for the same horsepower.

The biggest problem in modern times is the factory has fought what helicopters do well, being a Swiss Army knife. They are tools. We needed camera mounts. We had to develop one ourselves. There is one for the turbine but we needed one in a different place. We had to come up with our own radar alt installation for our 135 aircraft, they blew us off on that with no alternative. They had their own projects but they were for government contract stuff not in the US. We had all sorts of ideas because we made them work.
 

EzyBuildWing

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Great heli-vid here......low level, Iceland to Scotland in an R-66.....
Enstrom never had "Ramp-appeal" to me..... mast looked like a child's clockwork wind-up toy .......sort of insubstantial, like a single 2" square gyrocopter-mast, which always had me crossing-my-fingers hoping the engineers got it right, and the metallurgy in that long cantilever-shaft was still good!
For passengers, joy-flighters, etc, heli must have ramp-appeal.....sort of a "wow, that looks awesome" factor...... to me, Enstrom's mast and tail made it look like a contraption that had been short-changed in the "aesthetic-appeal" stying-department.
Enstrom mught consider getting Mike Pattey of "Scrappy" fame to design/build an attractive carbon-fibre mast-shroud etc....he'd probably do it in a day!
Here's that Iceland vid:

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Enstrom with bigger windows.jpg
 

BBerson

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Enstrom never had "Ramp-appeal" to me..... mast looked like a child's clockwork wind-up toy .......sort of insubstantial, like a single 2" square gyrocopter-mast, which always had me crossing-my-fingers hoping the engineers got it right, and the metallurgy in that long cantilever-shaft was still good!
Sorry to inform. The R-22 mast and rotor head failures killed more than 30 and then the FAA issued a mandatory special FAR for the R-22. I looked up all the R-22 NTSB fatal reports. The one that got to me was where a young women on her first helicopter lesson had a recording device in her pocket. It recorded her final screams when the rotor came off.
I switched to Enstrom, no rotor failure death that I can recall.
 

D Hillberg

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Sorry to inform. The R-22 mast and rotor head failures killed more than 30 and then the FAA issued a mandatory special FAR for the R-22. I looked up all the R-22 NTSB fatal reports. The one that got to me was where a young women on her first helicopter lesson had a recording device in her pocket. It recorded her final screams when the rotor came off.
I switched to Enstrom, no rotor failure death that I can recall.
Robinson had QC issues with the first batch of R-22s , bad blade prep where the assembly process was ignored.
The R-22 was not designed as a trainer - It's a sports car, Mast bumping isn't a new issue [Bell, Hiller do the same]
The Enstrom is a truck and lately they had a rotor head spindle fail [an old abused piece] AD issued.
TT strap mod removes the AD for a piece that failed because of bad maintenance.
I've seen more reports and the common thread is lack of pilot training or retained skills.
Mast bumping and Droop stop pounding are pilot issues.
Army went to Bell TH 57 trainers and the common issues I've seen with pilots coming out of the Army is power management...[They've wrecked more helicopters then newbies in the R-22]
And don't get started with the "governors are safer" BS. Got hundreds of hours before R-22 went governed.
Lazy wrist and toes cause accidents like lazy brains do...........
 

D Hillberg

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The Robinson Special Federal Regulation addressed the need for special training to avoid low ”g” and rotor loss.
Army came out with procedures in maneuvering with OH 58 and UH 1 helicopters. Low G - Mast Bumping & Critical wind azimuth . NOE was snapping off masts.
The R-44 has more issues of pilots not using proper power management and over pitching and power topping.
again a poor piloting issues.
 

TFF

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Unluckily two people have died from rotor head failure in 56 years of manufacturing helicopters. It’s what caused the TT strap AD. The way the FAA handled it after the first AD pretty much boned every Enstrom owner because the FAA got a case of CYA. There was another one, but they were not sure if there was sabotage involved; foreign aircraft. Factory was being blocked on its investigation. Not saying they haven’t crashed any, but deaths from mechanical failure is quite rare.

Better now, but R66 had a terrible safety record in the beginning. At one point, if one person died in a R66 crash, everyone on board died. They were 100%. Enstroms are tanks and Robinson are fragile relatively speaking. A Robinson R66 is lighter than its R44; it’s actually as light as an Enstrom A model when new when you could buy an aircraft without a radio or transponder. That plays different ways. Pure performance, you can’t beat it. Cargo bay, you can’t beat one. It’s payload is almost as much as it’s ramp weight. When there is no performance, good chance it will beat you; there is nothing extra to leave in your pocket. Margins are not there. New Zealand does not allow government employees to ride in Robinsons anymore. No government contacts allowed for those aircraft. For whatever reason, they can’t keep them from mast bumping there. Full mast bump and there are no rotors over your head. 19 have died in New Zealand from this.

Bashing Robinson is not really the intent. What Robinson flying issue is if something goes wrong, you have to get everything right. A Robby pilot with 2000 hours in type is usually not the issue. Issue is either low time pilots doing a No No or ex military pilots thinking they are flying an Apache or a Sea Stallion. Military pilots and piston helicopters without transition training is usually a problem. They are use to horsepower fixing problems. An Enstrom is certified to -.5 G. There is a big margin having this. You can push the nose over almost like an airplane. It’s not a Hughes 500, but for price it isn’t bad. For new pilots, a sneeze at the wrong time won’t kill you.
 

TFF

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For worrying about strength of the Enstrom shaft, I believe it is three times stronger than a Jet Ranger one. The big diameter wins even though it’s not as thick.
 

D Hillberg

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For worrying about strength of the Enstrom shaft, I believe it is three times stronger than a Jet Ranger one. The big diameter wins even though it’s not as thick.
Enstrom came out with mast lite and had to add a layer of Kevlar to keep it from flexing....Back to the original

I'd like to see where those Spitfires went...
 

Martin W

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Perhaps I’m missing something blatantly obvious but it seems as if Maule can throw just about any kind of propulsion on their airframes?
Perhaps I’m missing something blatantly obvious but my comment was about helicopters
Maule does not use a transmission , helicopters do.
Gearbox limitations often determine horsepower limitations in helicopters
thanks.
 
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