Autos - Backwards

[swsw]

Anyone tried autorotations flying backwards ?


Any tips ?


Regards,

Steve

[SASless]

Do not "Flare"....one must "Un-Flare":E

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!:E

[Heliport]

"There was a young man from Ghent
........
............
and instead of coming he went." ;)

[SASless]

...To stay out trouble....

[Thud_and_Blunder]

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.

[PPRUNE FAN#1]

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...

[Thomas coupling]

I'll give it a go:


gniylf snoitatorotua


how's that? :bored:

[Gav500D]

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!

[oxi]

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..

[rotorrookie]

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...

[WLM]

RotorRookie
By 500' you must be in forward motion at 60kts

[NickLappos]

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.

[tcamiga]

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 .

[swsw]

Tcamiga,

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

Thanks,

Steve

[tcamiga]

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

[TeeS]

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

[tcamiga]

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".

[rotornut]

WARNING: DO NOT TRY IN A HUGHES 500!

[FlyAny]

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.

[overpitched]

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 !!!

[rotorrookie]

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. Why not do 360 auto rather than backwards? One of my instructor demonstraded a 360 from hover at 500agl in a H-300, well we had with 15kts wind

so 360auto should be possible at 800agl when doing 50kts

or is backward auto better choice than 360auto?????

[221B]

The advantage of zero spped or backwards is that you can keep the landing site in sight - a 360 can be disorienting. The other option if you are close but not past the site would be s-turns

[Darren999]

221B

Agree with keeping landing area in sight. I teach on the 47 and demonstrate an auto backing up, if you do wish to transition to forward flight to finish the full down auto I have found not to push the cyclic forward to much, this has a tendancy to unload the head slightly, thus losing RPM. You can then bring the 47 to a zero forward speed auto. I must admit took me a while and a lot of practice before I tried a zero speed auto. Just nice to know you can land it in tighter spots if the donkey stops...

[Woolf]

There seem to be two threads going on here:

Some posters are talking about autorotations with an element of rearward flight BUT a forward flare and touchdown.

Others describe a full rearward auto with rearward touchdown!!!

I think most pilots would have tried the first but hat off to anyone who has tried and survived the latter!! The Bell 47 seems an ideal aircraft to do this with plenty of inertia in the blades. Would not want to try this in an R22 - not much margin for error.

[Daedal_oz]

Woolf said:

Some posters are talking about autorotations with an element of rearward flight BUT a forward flare and touchdown.

Others describe a full rearward auto with rearward touchdown!!!


I must admit to being confused too. I have done backup autos after entering auto in forward flight but for the life of me I can't imagine anyone flying backward at a speed that would allow succesful autorotation. Surely such speeds exceed the flight envelop for rearward flight and would create all sorts of tail rotor instability problems? Isn't it enough that you have to deal with one (major) emergency without adding to it be creating control problems?

And how does one judge the touchdown point? (or aren't we talking touchdown autos here?:confused:

[oldbeefer]

You are all BARKING MAD!