Forced landing discussion re wheels up or wheels down
 

The latest ATSB Short Investigation Bulletin has a report on a Beech Staggerwing accident.

See: Investigation: AO-2014-098 - Engine failure involving a Beech Aircraft Corp D17-S, VH-FNS, 12 km ESE of Bunbury Airport, Western Australia on 31 May 2014

Allowing for the fact it is a "Short" investigation, I wonder if the full investigation will discuss the pros and cons of a forced landing with wheels down as against landing wheels up, as in the case of this accident. Of course if gliding distance to the forced landing area is a factor to be considered, then usually best gliding speed and leave the gear up for least drag is normally an important consideration.

On the other hand, once over the field with altitude to spare, consideration of the advantage of wheels down is important. For example, availability of wheel braking and energy absorption on a rough surface.

The ATSB report mentioned the pilot elected to keep the landing gear retracted but did not say on what factors the pilot based his decision. Well I suppose it was a "short" investigation. That seems a pity, as much depends on the adequacy of training the pilot had received in the past on operation of retractable gear aircraft. And that includes if that Design Features training had adequately covered the factors to be considered when deciding to land wheels up or down. I believe very few flying instructors know about these factors; especially junior instructors who, for no fault of their own, often lack real world experience beyond their own CPL.

That said, there is no shortage of information on the internet regarding wheels up or wheels down in a forced landing, so ignorance is not really a valid excuse

I haven't had the pleasure of flying a Staggerwing, but from a conversation with an experienced pilot, it is possible that the gear system on the aircraft may have influenced the decision in this case - glacial and involving a certain amount of manual input apparently.

Can someone just tell me if I should leave it up or down? So many arguments for and against.

Cos when the engine does fail I'm going to be umming and ahhing all the way to the ground :}

It's pretty black and white on my checklist. Gear as required! :ok:

SIDs almost (or past) due? Gear settings as required for airframe writeoff.

My default for an off-aerodrome landing in a retractable is "gear up"!

That said, if circumstances at the time indicated that "gear down" was likely to have a better outcome, then I would consider it.

I have landed quite successfully on a variety of roads and paddocks in the past 40 years!

Dr :8

Esmeralda Station anyone ...
 

Forkie, I once landed here, went for the wheels down type of landing, but it was still pretty exciting. Once was enough, getting in is easy enough as you have a good view of the road for many km in either direction. Getting out is a little more risky ... it's the single lane bitumen road between Croyden and Richmond, FNQ. We did have spotters/traffic control for departure, but it takes a lot of room to pull up an 80 tonne road train.

Esmeralda Station

Had an engine failure on climb-out (in the right seat) of a Mooney M20. The P1 was very experienced on assorted aicraft and the field. We gently circled back (I know....) and landed across the strip. As there was a big hedge looming, the P1 said If I thought we would clear it, get the gear down. Luckily it was the manual type and I banged it down as the hedge dissapeared under the nose. Result: no damage to the airframe, but a few bits of hedge in the gear.

Gear down the gear takes any impact, gear up your spine does.:hmm:

The Beech 17 POH I have (USAF Publication AN-01-99OC-1) makes the following statement regarding forced landings:
"If within gliding distance of an airfield make a power off approach and landing, if not keep the landing gear in the retracted position and make a belly landing". Very similar wording to AT-6 (Harvard) manuals. All Yak piston retract model manuals (18T, 50, 52) also state "off field" landings are to be made with gear retracted. There is an increased risk of nosing over during a forced landing on an unprepared surface, which may make egress difficult.
Bottom line, refer to the POH for the type, weigh up pros / cons if the manual is silent on this subject before you are faced with the decision. Back injuries are likely if a gear up landing is made, however it's better than being trapped in an inverted aircraft, particularly if there is a fire or no help at hand.

Generally ensure the gear is down if a forced landing occurs in a tricycle landing gear aircraft on an unprepared surface. The energy forces at impact are taken by the landing gear followed by the fuselage if the landing gear gives way. Less risk of severe spinal damage if the landing gear takes the initial impact. If the gear stays intact then you have the advantage of using wheels brakes and maybe even limited directional steering to further avoid surface obstacles.

That is why this scribe would prefer to be in a Cessna 172 rather than a Tiger Moth for example if faced with a forced landing with no power since there would be a strong likelihood of the Moth tipping over on touch down due to its tail-wheel undercarriage design. Many fighter aircraft in WW2 were tail wheel design known as conventional undercarriage. Because of this factor forced landing on unprepared surfaces were always wheels up.

With the advent of jet fighters like the Sabre with their relatively high landing speeds, significant spinal injuries were noticeable when landing wheels up on unprepared surfaces. The technique was changed to wheels down with the theory that the landing gear would absorb much of the initial energy of impact as it was designed to do. Even if the landing gear breaks off at impact or during the landing run, it has done its job of absorbing some of the energy which would be otherwise be taken by the fuselage underside and the pilot's spine.

The Boeing 737 Flight Crew training Manual reinforces the theory of the importance of energy absorption by its advice to try and land with at least one landing gear extended rather than fully wheels up. It does not use those words exactly but has checklists for partial or gear up combinations.

Did you manage to take off again too? :E

For mine, if you're going to come down on land, gear down. If it's going to involve a post-landing swim, or wading out through a swamp / rice paddy or similar - the flying boat landing on the "hull" might be appropriate - but only to prevent the severe forward pitching and deceleration that gear down will cause in water (resulting in a good head-butt of the glareshield, I imagine).

My experience has been that a gear up landing, even on a relatively smooth runway has a high probability of a severe spinal injury (amazing that a less than 1" displacement of the cabin floor will blow out vertebrae...) - which corroborates what Tankengine & Centaurus have stated above... The fuselage is not designed to take too much in the way of a vertical hit, but the undercarriage is (and does - on a daily basis!!) and the more metal between your bum and the Earth the better.

Even if the ground is rough and the nose gear tears off, you are still likely to fare better, in my opinion - corroborated with observations of many light aircraft accidents / incidents over the years.

Probably due to wheels being partially exposed anyway in this position ala Queenairs? Better cushioning than a fully covered gear. Second tank's motion on spinal damage.:ok:

Not sure I concur with wheels up on water...only considering tricycle configuration.

Water is incompressible, Dirt is compressible. I think I'd like the legs out to break the surface of the water.

Thought based on 30 years of falling off dirt bikes, and water ski's....i know how much it hurts.

If the Tiger tips over in a forced landing it will do so at a low speed and will be resting on its upper wing. If the surface is that bad the Tiger will tip, then the Cessna will probably wipe off the front gear leg and turn its tummy to the sky, too.

If a WWII fighter such as Hurricane or Tempest or whatever tipped over, it did it at high speed 75-120 knots and landed on its canopy because of its low wing configuration. Pierre Costerman describes the experience in some detail in his autobiography.

I'd rather be properly strapped into the Tiger or my Auster in that situation.

Kaz

I remember reading years ago in an RAF flight safety magazine the recommendation to lower the gear for a forced landing as the theory went that as parts of the gear were torn off so energy was reduced. The physics seem sound to me but I'm sure it's not that simple?

OK, you learn something new every day!

I have always wondered why so many people who are involved in a wheels-up landing, either due to gear or brain malfunction, suffer "severe spinal injuries". :E

Dr :8

It is that simple - otherwise I am sure the RAF would not give that advice. Of course there is no shortage of speculative "but what if's?" but the lower the energy at impact the safer you should be. Please forgive the "war story" but interestingly, in another era where yours truly went from flying Mustangs (tail wheel type) to Vampires (tricycle type), wheels up policy for forced landings on both types of landing gear on rough surfaces, was still in vogue; mainly from our ignorance and lack of any official advice to the contrary.

Later when I sort out how to put the photo on Pprune, I will post a classic photo taken in the 1950's of an RAAF single seat Vampire on its belly where the pilot decided to force land wheels up in a field after his formation leader got them lost them lost near Cooma NSW on a navex. He was uninjured in this case. (Gooday, Bill, if you are still around!)

It wasn't until US and RAF military flight safety magazines began to filter down to RAAF squadrons, it dawned upon people that wheels down forced landings into unprepared surfaces for new fighters like the Sabre and the Century Series fighters were proven to minimise back injuries if the wheels were down. Might also be safer to eject on those hot ships, too

If the wheels are stuck up in a lighty and you have the choice of bitumen or dirt! Land on the bitumen. Less chance of digging in. You slide you see!