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Autos - Backwards

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Old 21st Sep 2005, 14:16
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Autos - Backwards

Anyone tried autorotations flying backwards ?


Any tips ?


Regards,

Steve
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Old 21st Sep 2005, 14:39
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Do not "Flare"....one must "Un-Flare"

Did fly backwards on an GCA one time....the Italian Final Controller got a bit confused for a bit....when he realized I was no longer inbound but was actually outbound. Chinook flying had its moments!
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Old 21st Sep 2005, 15:10
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"There was a young man from Ghent
........
............
and instead of coming he went."
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Old 21st Sep 2005, 16:54
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...To stay out trouble....
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Old 21st Sep 2005, 19:03
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Only time I ever saw one was on the UK-Italy Shawbury-Frosinone trip. The Italian Air Force was still using B47s, and the party-piece for the fella I flew with was a backward-360 engine-off landing. Fun, frivolous and f-all use - worth seeing once I suppose to say you've done it.
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Old 21st Sep 2005, 19:43
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Back in the 1970's, a certain Enstrom factory demo pilot by the name of Michael ("Crazy Mike") Meager, whom Dennis Kenyon cites as inspiration, used to do a little demonstration in the F-28 in which he would do backward touchdown autos. Never actually saw him do it, but know plenty of people who did. Gutsy, man. Then again, at least you don't have to worry about hitting the tail...
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Old 21st Sep 2005, 19:52
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I'll give it a go:


gniylf snoitatorotua


how's that?
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Old 21st Sep 2005, 21:10
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Make sure you have pently of height if you are trying it for the first time and keep RRPM at the top throught, you need to bring back your speed to a/s zero rather quickly in order to achieve this. And you will only fly backwards relative to the ground aswell so if there is no upper wind you won't fly backwards. Be careful not to attain a/s to quickly when you decide its time to get some energy to flare as the RRPM will bleed off very quickly so lower collective first.! have fun cos it is!
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Old 21st Sep 2005, 22:44
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Used to show students on the odd occasion from a hover at about 1500 ft if I remember correctly, close the throttle, fall vertical for a bit to recover some rpm ( never let it out of the green), then start heading backwards pretty amazing what the R22 is capable of....... just make sure that you have that 60 knots by 500 and in the right direction..
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Old 21st Sep 2005, 23:02
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just make sure that you have that 60 knots by
How can you determine the speed so precisely when going backwards???
maybe by putting another pitot on back?. just curious...
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Old 22nd Sep 2005, 01:34
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RotorRookie
By 500' you must be in forward motion at 60kts
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Old 22nd Sep 2005, 02:01
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In the Bell 47 (OH-13) my first instructor showed me a backward auto, which is flown precisely like a forward one, but backward. At about 300 feet, he put the nose about 5 degrees nose up, entered from a forward auto, and the airseed bled down to zero, then rearward. Close to the ground, the airspeed was minus 25 or so. He did the flare as a smooth nose down to about 10 degrees, with a stop at a low skid height, and a nice touchdown.
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Old 22nd Sep 2005, 06:47
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autos

A rotor disc is a rotor disc - I taught this manouver for years to all students in the R22 and 47.

Using the rule of thumb of 400 ft for every 90 degrees of turn in the R22, the question was raised how do you land in an area that is just passing under the machine when at 800 ft AGl above 53 kts and the engine quits.

Enter normal engine off configuration and keep the Cyclic coming back smoothly. Trading Fwd energy for Altitude, the machine will not loose too much altitute and MRRPM will stabilise within limits.

You will feel transition go and then return as the disc takes the machine backwards. The nose will pitch down when this occurs.

At this point you will see the touchdown spot and can judge how long to hold the "rearwards flight attitude."

Then - cyclic forward - thru transition, nose down quickly and smoothly down (quite a bit) to gain above the flare gate speed of 53 kts, cylic smoothly aft and hold the IAS above 53, flare and land. Simple.

Similar deal in 47.

I never use cyclic in the flare before touch down as I consider it to be a "Hand Brake" on the Rotor energy.

Think about the advantages of this if you have to drop into a vertical hole in the bush from 50 ft AGL .
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Old 22nd Sep 2005, 09:00
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Tcamiga,

That's exactly how my instructor demo'd this move.

Thanks,

Steve
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Old 22nd Sep 2005, 10:12
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auto

Just checking - you lot are a bit slow - it should have been "I never use collective in the flare"
in my last post.
http://brumbyhelicopters.com.au
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Old 22nd Sep 2005, 10:31
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Hi tcamiga

Nice interesting site.

One query though, in your hasel checks you state -

"Carry our your H.A.S.E.L. checks including application of full carb heat to keep the engine from cooling too quickly."

Is that your understanding of why carb heat is applied?

Not intended as a dig.

Cheers

TeeS
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Old 22nd Sep 2005, 12:10
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Hi TeeS

No probs about the question.

We were routinely doing up to 30 or 40 and sometimes 50 EOL's to the ground each day.

The application of Full Carb heat was to keep as much heat as we could in the engine internals to reduce mechanical thermal shock damage due the changes in temp when the throttle was snapped shut.

It also made the mixture slightly richer, which we considered an advantage when running an engine that had the mixture manually trimed from "over rich to normal".
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Old 22nd Sep 2005, 21:36
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WARNING: DO NOT TRY IN A HUGHES 500!
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Old 23rd Sep 2005, 03:28
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In Army flight school in the late 60's at Fort Wolters TX., many of the Southern Airways instructors were willing to WOW the young student pilot with an occasional backup auto in a Hughes 269A.

I went back to Wolters after RVN and did a few in the 269 myself.

Went to Fort Rucker and tried to demonstrate one in a UH-1H to my students one day. After all, a Vietnam warrior, high-speed instructor who was as good in an H1 as I should have no problem with a maneuver he had done several times in a "lesser" aircraft.

Worked fine till enough air got on top of the Sync Elevator to pitch the nose up abruptly. One of the oddest ways to enter a hammerhead you might imagine.
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Old 23rd Sep 2005, 04:29
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Where's Imabell

I thought he mighyt have pitched in a couple of cents on this topic. I've seen him do a full backwards circuit at an airshow once. I guess there would be some fast work required if the engine quit during that demonstration !!!
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