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        Discussion All gas helis can auto rotate....right?

#1 3D-flyer-93 May 30, 2012 07:45 PM

All gas helis can auto rotate....right?
 
I was browsing some all threads and one guy had posted that some .30 helis cannot do auto rotations.


I just got a Jr Venture .30 and was hoping to do some autos....is it possible, or not?

#2 Brutus1967 May 30, 2012 08:12 PM

Would not know of a reason why.....

Had a Hirobo Shuttle ZX back in 92 or 93 and that could allready do good auto's stock out of the box....

Brgds, Bert

#3 Roto Rob May 30, 2012 08:57 PM

Never seen a 30 size that could not autorotate. Many do not have the the hang time of a larger helicopter. Also some like my Raptor 30 do not have a driven tail rotor in an auto. This will limit the tail control during an auto, it will tend to weather vane. The helicopter at the end is my Raptor 30, doing an auto due to the engine stalling.
Rocky Mountain 3D Throwdown Highlights (3 min 44 sec)

#4 Cyclick May 31, 2012 01:38 AM

No doubt about it, even a 30 size nitro can auto, and a light one like the Hawk Pro will do so more easily then a heavier Venture 30 or Rappy, but they will still be able to do so.

Check out this video of the Hawk Pro, doing straight in autos, 180 degree autos and even 360 degree autos. (at the 2:17, 3:07, 5:36 marks and at the end of the flight.

Fun with Hawk Pro 30 (6 min 17 sec)

#5 rotoraddict May 31, 2012 11:19 AM

+1 to the auto capabilities of the Hawk Pro. I find mine autos better then my belt driven 50's. I have installed the optional tail driven auto unit in mine. I find that the shaft drive tail takes much less energy from the rotors to turn the tail rotor in an auto, then do the belts.

I also like the dogbone coupling of the Hawk's torque tube. It will allow the boom to bend a fair bit in a crash before needing to replace the t/t. I find it has much the same crash survivability as the belts in my belt driven helis.

#6 Brutus1967 May 31, 2012 12:17 PM

Quote:

Originally Posted by Roto Rob (Post 21757331)
Never seen a 30 size that could not autorotate.

Hehehe, then you're not old enough.... Not only seen them, I've flown them.... Back in the eighties, many helicopters still had collective pitch and AR bearing as separate options.
Cannot remember much of them, except for the MFA Sport 500 (actually a .45, but in size similar to most .30's) that I flew for at least 2 years intensively.
Fortunately never had an engine faillure.... :D

Brgds

#7 rotoraddict May 31, 2012 01:02 PM

Here is a video of a 1/7 scale Hirobo Llama that was a great flying CP heli but came without an auto clutch. Later they offered one as an option, but the kits did not come with one. I later installed one into mine, but never did attempt to auto it at the time.

Hirobo 1/7 scale Llama 1989.mpg (4 min 3 sec)

#8 rotoraddict May 31, 2012 01:09 PM

As for driven tails. These came in many years later. The 180 degree auto was part of our maneuvers, in F3C competitions for many years, before the driven tail came into being.

As their is no torque to overcome in an auto, as long as you kept some forward flight happening, the large vertical fins we used, would just cause the tail to follow the tail as we would make the turn.

We could also do 360 degree and S turns on the way down. But now with the driven tails, it is a lot easier to do these. Of course, without a driven tail, one could not even consider doing any backwards autos or the types of aerobatic autos we do today.

#9 cmulder Jun 01, 2012 01:44 PM

not all
 
Lite Machines Model 110 Helicopter (take a look here http://www.rctech.net/forum/rc-fligh...elicopter.html)
Does NOT auto rotate since just like the fma sports 500 it is a fixed pitch heli.

btw its not in production anymore just to be complete ;)

#10 Brutus1967 Jun 02, 2012 02:29 AM

Quote:

Originally Posted by cmulder (Post 21773142)
Lite Machines Model 110 Helicopter (take a look here http://www.rctech.net/forum/rc-fligh...elicopter.html)
Does NOT auto rotate since just like the fma sports 500 it is a fixed pitch heli.

btw its not in production anymore just to be complete ;)

Euh... the MFA Sport 500 was a CP heli.... owned two.... definitely CP....

#11 str8wing Jun 02, 2012 11:57 PM

The MFA Sport 500 (Sold by Hobby Lobby) was originally fixed pitch... I learned to fly Helis with one back in the middle 1980s. They came out with a collective pitch "upgrade" when RC helicopters really started to catch on. The Kalt Baron 28 didn't have an auto clutch initially. They added them later, though with unweighted wood blades not many autos were successful. My how things have changed... :-)

#12 cmulder Jun 03, 2012 05:13 AM

more info
http://www.vrhc.co.uk/rc%20helicopters/UK/MFA/MFA.htm
makes me wonder with today's more powerful engines how the performance would be,

#13 Brutus1967 Jun 04, 2012 08:52 PM

Quote:

Originally Posted by cmulder (Post 21786844)
more info
http://www.vrhc.co.uk/rc%20helicopters/UK/MFA/MFA.htm
makes me wonder with today's more powerful engines how the performance would be,

Not.... I t would tear itself apart! Clutch and bevel gears would not stand up to more power.
My first Sport 500 Collective (bought 1989 I think) tore away the engine mount approx every 3 to 5 hours of flight, with first the not really powerful HB 40, and later with the only slightly more powerful but very smooth running OS 40 "longstroke".
Flew it quite intense for approx 2 years, and was quite happy with it, actually.

my second one, more than 10 years later, had a .45 Bluebird (some poor OS copy) and that one lasted for maybe 4 flights after which the crack-fest started again. That time it was just misplaced nostalgia, so I quickly got rid of it....

Brgds, Bert


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