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SFHeliguy
6th Feb 2003, 21:49
All,

I just read the following:

"Sloping Terrain: In attempting a landing on sloping terrain, it should be made up-slope. In other words, with the skid gear paralleling the slope of the terrain. Again, it is better to attempt a landing up-slope than one down-slope"

is this consistent with your thinking?

handyandyuk
7th Feb 2003, 00:22
First thought that comes to mind there is come the flare wouldn't the TR be uncomfortably close to the surface in a downhill FL?

Surely facing uphill by the time you've flared you're already halfway to being level for the landing apart from having far more clearance for the TR?

I am but a low time PPL... I might be wrong.

SASless
7th Feb 2003, 02:14
Upslope has some merits....think of the attitude change you will have trying to perform a flare type deceleration...not dig the tail rotor/tail stinger into the dirt....and get the nose back down to a landing attitude (somewhat nose down it would seem) and then get the machine stopped without going for a sled ride down the hill......errrrr...definitely upslope me thinks. Or....the ol' logging pilot concept of smashing the uphill skid into the dirt so that the helicopter sits more level (heard it discussed....never had the courage to try it!).

pa42
7th Feb 2003, 02:32
Thanks for the new nightmare image. Arrrgh.

I concur, however--even though pointing the soon-to-be-scrap helicopter UPhill is unnerving, it has a faint chance of not rolling down the hill backwards (visions of kangaroo balancing on tail!). One would, however, instantly sympathize with folks who jump out of burning buildings to avoid flames. Query: do you brief the passenger(s) in the heli to be leaning out the doors & jump at 6' just before impact??

Making the touchdown crosswise to the slope would appear to guarantee instantly rolling downhill--no way to keep from bouncing away from the slope, then falling vertically back to it, hitting on uphill skid, bumpity, bumpity, bumpity. Maybe the pilot should jump, too.

As Handyandyuk implied, pointing the doomed ship downhill is surely the worst option. "Snap!" goes the tailboom, "crackle!" goes the tail rotor, "pop!" goes the cockpit bubble as it impacts pointed straight down after the heli trips on its tail. Newspapers will have a field day--"The Rice Crispies Helicopter."

Sorry about that, don't know what possessed me.

ShyTorque
7th Feb 2003, 08:08
Well chaps, if the time ever comes (and let's hope it never does), it would be nice to have the choice about the precise niceties of the slope....

The slope might well be just one factor in deciding where to skilfully grease the aircraft onto the terra firma. If the aircraft can't be brought to a complete stop in the air, it will be a fencepost hitting me between the legs that worries me most.

So if I had the choice it would definitely be uphill or along the slope, for reasons already stated but preferably into wind.

Of course, if you land outside of the published sloping ground limits don't forget to write it up in the tech log ;)

BigJim
8th Feb 2003, 22:52
Gents,

have had the non-pleasure of having to make an autorotation landing down hill!

The funny thing is that brand new tail rotor blades had been put on the helicopter only a few weeks earlier and thats all I could think about while flaring.

It was a no wind day with lots of dew on the paddock where I landed - Skidded downhill for about 45 meters but kept the helicopter upright and in one bit, but the low skids where even lower!

I funniest thing about all this is a passenger, two moments before the engine failure had asked me what happens in the event of a failure?, my reply, no problems you simply glide down to a landing. As soon as I said that - Bang, we're in auto. Hows that for Murphy doing his best!

BigJim

SASless
9th Feb 2003, 06:51
BigJIm...ain't you glad he didn't ask about losing a rotor blade or something?