How would you autorotate into a steep hillside?

[betr_thn_Icarus]

How would you auto into a hillside if it was your only option/best option and it was way too steep for a normal landing? Would you auto in nose uphill and hope the tail stopped you from sliding? It seems like if you came in sideways you would roll down the hill for sure. Or nose down no way to flare and also initiating a roll as well. I don't remember ever getting a lesson on this reasonably likely possibility. Now working on my CPL.

 

My vote goes to nose directly uphill. Do the flare and never level out of it. I suspect you might even get out of it with only some tail boom/rotor/driveshaft damage.

 

What do you guys and girls think?

[JDHelicopterPilot]

This is a scary prosepect. Is it just a bit of a slope or a steep hill we are talking about. Best bet if you can head to the bottom. At the end of a hill you'll most likely find a valley that has some level area to it. If you auto into a hill and flare then don't level as you suggest I wonder if I wouldn't end up rolling all the way to the bottom. I'd rather be at the bottom and if I roll over at least I will only once. Sometimes there may be a large enough of a flat area on top of the hill or ridge to go for. This is harder and better make sure you'll stay up there. A lot of these things really depend on the situation. There isn't one right way to do it that fits all situations we may encounter.

 

JD

[apiaguy]

absolutely shoot for the bottom... if it is a ravine so be it... I'd rather take out the blades and entire airframe in the bottom of a ravine than bounce off a slope and roll down there.

[Gomer Pylot]

You're almost certain to roll it up into a ball, with pieces flying all over hell and half of Texas. The objective is to survive. I would probably choose to land into the wind if it is at all significant, because I want to hit with the least forward speed possible, regardless of the orientation with the slope. I don't want to hit solid obstacles. If there is little wind, I would likely try for the bottom, but in many cases there are big trees down there, and the slope may be more open. It's pretty much impossible to say for sure what to do, because every case is different. You have to just make a split-second decision and try to live with it.

[BOATFIXERGUY]

With tons of time flying helicopters in the Colorado Rockies, this has always been a major concern everytime I fly there. As Gomer Pylot said, you may not be able to make it to the bottom. You have to make a fast decision and stick with it. You probably wont have much altitude to work with, and if you're flying up a face, you are already into the wind. Turning downwind into the canyon might not be an option. Anytime you cross a ridge, you'd better be in the wind or you wont make it.

 

Now in mountainous areas without incredible density altitude or crazy winds, try for the bottom. Usually you can find a clearing in the bottom.

 

john

Edited October 16, 2007 by BOATFIXERGUY

[TheLorax]

with all of his wisdom and experience i think the only right answer is what the pylot says: make a split second decision and try to live with it. living with it could mean being paraplegic the rest of your life or surviving without a scratch. makes all the sense in the world to land into the wind as well. if it came down to it.... i have no idea what id do.

[betr_thn_Icarus]

Yeah I was picturing not having much choice. Generally the water is at the bottom and some REALLY big trees grow down there. I know a drop from 100 feet, or whatever the tree tops are, wouldn't be too fun especially hitting things and tumbling on the way down. Plus a rescue wouldn't be able to spot you. I guess what I meant was that you already made the decision to land on the slope because it was your best option.

 

Thanks for the answers. I have found myself in a few situations where I didn't really like the idea of any of my options and I don't work for anyone flying.

 

I'm sure some people working in a heli find themselves in this situation all the time. I guess you make the best of any situation and try to have your reaction in mind already.

 

I find myself flying at 700 now more than 500 unless there are a lot of options.

[Witch]

How about trees? Nose first? Tail first? Straight down? Oregon has a lot of logging roads, but a lot more trees to land in.

 

Thoughts?

 

Later.

[HelliBoy]

How about trees? Nose first? Tail first? Straight down? Oregon has a lot of logging roads, but a lot more trees to land in.

I've been told to put the advancing side of the disk into the trees if you've got no choice, it supposedly keeps the mast and transmission from coming into the passenger compartment.

 

When I absolutely have to fly over vast streches of udevelloped woods I look for clusters of dense trees...I'd rather be hitting branches slowly on the way down than the ground very quickly. Theres a pic of an MD500 floating around where he'd auto'd into the biggest, gnarliest tree in the jungle and hung it upright in the canopy, no MR blade seperation even.

 

As far as the slope hypothetical goes I'd be more afraid of rolling to my death than the impact; I'd probably try to make sure I had something the stop me from rolling mre than once.

 

Interesting topic; we're not taught how to crash but if it ever happens any tool we have is better than nothing

[ben_davenport]

If it came right down to it and I had no other choice but to go to a hill I would auto going up the hill and not pay as much attention to the wind. That way I would be able to get my skids parallel to the ground without having to worry as much about my tail rotor/boom. Going up hill I would be able to flair more effectively and slow my ground speed down more. Going down hill there is now way of getting my skids parallel to the slope and flair effectively at the same time.

[500E]

There we go again the helio drivers think the worst, STEEP\NEAR VERTICAL hill.

Hills come in all sizes.

BenD has a good point the steeper the slope the more you could flare + skids parallel to hill, sounds good.

Would the weight of eng\tx up hill and tail down help with any role moment in theory the tail could act as a prop.

Trees seem to be bad news the idea of hitting with advancing blade sounds worth a try, at least you would feel that you were doing something.

[JDHelicopterPilot]

There we go again the helio drivers think the worst, STEEP\NEAR VERTICAL hill.

Hills come in all sizes.

BenD has a good point the steeper the slope the more you could flare + skids parallel to hill, sounds good.

Would the weight of eng\tx up hill and tail down help with any role moment in theory the tail could act as a prop.

Trees seem to be bad news the idea of hitting with advancing blade sounds worth a try, at least you would feel that you were doing something.

 

 

 

At the very least it MAY give you enough time to jump out before it starts to roll. I wouldn't count on the tail holding up anything. Keep in mind from what I have read in the NTSB reports more offten than not actual forced landings even to level terrian lead to split skids, bent tail and blades. Every situation is going to be different. There really is not a right way for all.

 

JD

[Gomer Pylot]

I had a good friend hit a treetop with the blades of a UH1, landing on a mountaintop, on the left front, and it threw a piece of a branch into the tail rotor, whereupon things got out of hand. I think the right side would be better, but I don't know if time would allow a selection.

[West Coaster]

eek.... tough call.

 

for me my answer depends on what my options are concerning what surrounds the open hillside. if it's the steep, open hillside or a forest i'd go for the trees. end the flare near tree top level, tail on the uphill side and dump her in backwards. that way the engine and transmission don't go thru you on their way to the floor below. if there is water within gliding disatnce i'm going for a swim.

 

if i have absolutely no choice other than the open steep hill... hmmm. aim uphill? maybe keep on as much speed and inertia as possible and at the last moment use aft cyclic and some collective to trade that inertia for a slight climb to try and parallel the skids with the incline of the hill. then hope for a hairy uphill run-on landing? if the surface of the hill is a mess, like a cut-block, do my best to bleed off all forward speed and plunk it down and hope the stinger digs in enough to hold it on the hill.

 

no right answers to this one i think, but a good brain-stormer for sure.

[betr_thn_Icarus]

Hey thanks for all of the thoughts and input. I know there is never a correct answer for each situation. My goal is to have at least tried to consider options for every emergency I can think up. Then my "intelligent memory", an actual function of the brain, can recognize those past thoughts or images I imagined and have something to form a reaction from taking into account the current situation. The point was to get people talking about it because I have asked a lot of helicopter pilots about this hillside landing and there reaction is usually something that makes me think they hadn't really considered that situation.

 

On trees: I climbed one of my palm trees in my yard to trim the dead fronds. It is about 50+ feet tall and although I have 18 to do I decided not to climb any more without some serious safety equipment. I wouldn't want to fall from 50 feet.

 

I wonder about going for the thinnest area and hoping the rotors hold up enough to get you to the ground vs. the thickest area and hoping it holds you up in the canopy.

 

My next door neighbor (crew not pilot) tells a Vietnam story of a lost tail rotor (hit by a lot of bullets) and autorotating into some trees instead of the patrolled water. He said they went through some fairly thick trees that had fairly small branches. The pilot recalled flaring into the trees and then pulling all the pitch he had at the bottom just before hitting the ground. He said the main rotor blades were really banged up but still mostly held together throughout the crash. He mentioned a massive vibration just after settling into the trees probably caused by the blades being unbalanced from breaking or picking up weight from the branches. Now I know your all picturing a Huey but he said it was in a "Loach", the best I can figure from his description this sounds like a jetranger.

 

He said his next crash, this time in what he calls an "A model Huey" was done purposely into a short but steep hillside of red dirt. He said the pilot was purposely trying to avoid the trees. They went in nose uphill and they just stuck there with the tail digging in. He also said the tail boom was in good looking shape(structurally damaged I'm sure) but the tail rotor was mostly missing and in pieces. He said they had to wait for what seemed like forever for the main rotor to slow down before they could run away from the crash because people would come out of the jungle to find the crash. The engine failed but they never found out why.

 

Side note: He said he went down 3 times and knew others who went down more. It sounds like there were a ton of new pilots and really really really poor maintenance and overuse. Also mentioned on preflight when it was done you often saw new bullet holes and tried to make sure whatever was underneath wasn't damaged. I can only imagine the balls it took to get into one of those helicopters knowing all of this.

 

I think this thread is about dead.

 

Thanks again.

 

-SOK

[500E]

LOACH =

The Hughes (later McDonnell Douglas Helicopter Systems) OH-6 was originally designed to meet the needs of the US Army 's LOH competition, but it gave rise to a large family of commercial, corporate, and private helicopters. Light, nimble, and easily maintained, the MD500, as it became known, is designed to carry four or more passengers in a small but comfortable cabin. Many different versions have been built for both the military and civil markets for a variety of missions and requirements.

 

Was also built with license in Argentina by RACA, in Japan by Kawasaki , in South Korea by Korean Air and in Italy by Breda - Nardi

 

Nicknames: Cayuse, Loach, The Egg

Type: Light Observation Helicopter (LOH)

Crew: pilot, observer and 4 passengers

Engine: one 317 hp Allison T63-A-5A

Weight: empty: 524 kg max: 1224 kg

Performance: max range: 611 km ferry range: 3560 km max speed: 272 km/h

Dimensions length: 7.04 m height: 2.59 m rotor diameter: 8.03 m overall length: 9.24 m

Armament: one 7.62 mm minigun with 2000 bullets or a 40 mm grenade launcher with 150 rounds of ammunition.

[aser]

If you want a good read about the loach in nam!

http://www.amazon.com/Low-Level-Hell-Hugh-...6840&sr=8-5

 

 

Regards.

[Gomer Pylot]

Loach was a corruption of LOH, Light Observation Helicopter. It started with the OH6 and carried over into the OH58, but the OH6 is what is more often meant. Its design allowed it to crash, have parts fly in all directions, and the pilot would walk, or run, away from the scene. There used to be a video of Hughes test pilots finding the avoid area of the H/V diagram - doing autos slower and lower, until they found it - rolled it up into a ball, parts flew all over the place, rotot and tailboom among them, and the pilots unbuckled and walked out. The pilots loved them, and hated the OH58 which replaced it, but they went away. They never caught on in the civilian world, because of several shortcomings, pax comfort and load-carrying ability among them. A few were used in the GOM, but were never widely accepted. The 206, OTOH, became ubiquitous, everywhere. Different horses for different courses.

[klas]

..It started with the OH6 ..The pilots loved them.. but they ..never caught on in the civilian world, because of several shortcomings. ... ..

 

I flew an OH6 not too long ago & absolutely loved it, & to hear what you just said about survivability I love it even more. What are the several shortcomings, other than the two you mentioned?

[Gomer Pylot]

The discomfort and the fact that they can't carry much of anything pretty much does them in. No baggage space, cramped cabin, all for only a few million dollars. Customers vote with their wallets, and Hughes is long out of business, and its successors aren't producing much of anything.