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-   -   Cessna 172RG forced landing. Gear up or down if given the choice (https://www.pprune.org/tech-log/632265-cessna-172rg-forced-landing-gear-up-down-if-given-choice.html)

Centaurus 7th May 2020 08:53

Cessna 172RG forced landing. Gear up or down if given the choice
 
The Cessna 172 RG Manufacturer's POH states that in event of a forced landing on a rough or soft surface the landing gear should be up.
This appears to contradict the general advice that landing gear on nosewheel aircraft is best left down if forced landing on unprepared surfaces. My understanding is this gear down policy is to do with energy being absorbed by the landing gear thus reducing the risk of pilot spinal injury.

Certainly that is SOP for military aircraft. Why should the Cessna 172RG be any different?

LimaFoxTango 7th May 2020 11:32

Not answering your question, but I'd assume having the gear down increases the chance of the aircraft flipping as the gear digs into the surface.

Pugilistic Animus 7th May 2020 12:32

Like LimaFoxTango just said that it may prevent a flip over or rollover ...gear up with that type of terrain would probably be no more difficult than landing a plane on skis which is the closest parallel I can think of. Anyone who's ever landed on skis will attest that it is very easy to do.

Centaurus 7th May 2020 14:31

In the days of tail-wheel military types (Spitfires, Typhoons, Mustangs etc) wheels up forced landings were recommended. That was because of the tendency of tail wheel aircraft to tip over nose first when brakes applied. There were many accidents where this happened and the pilot was trapped upside down in the cockpit often with tragic consequences if the aircraft caught fire.
With the USAF introduction of the Sabre jet fighter with nose wheel configuration, the much higher touch down speed of jet fighters meant a wheels up forced landing was severe on the pilots spine due to the energy being absorbed by the bottom of the fuselage directly on the pilots spine.

This led to wheels down being the preferred method of a dead stick landing. Even the landing gear being torn off on impact meant excess energy was dissipated and less chance of pilot injury. Tricycle landing gear aircraft have much less chance of tipping over than a tail wheel type.

Depending on the surface it also meant that brakes could be used to shorten the ground roll. All this was evident 70 years ago and wheels down forced landings for nosewheel types (unless ditching) have become SOP since those days.

RVF750 7th May 2020 16:59

There was a recent touch and go on a soft wet grass runway on the Isle of man that resulted in the aircraft digging in and flipping onto it's roof. Try Googling M-GOLF and you should see the result of it.
https://www.google.co.uk/url?sa=i&ur...AAAAAdAAAAABAD

Pugilistic Animus 7th May 2020 21:21


Originally Posted by RVF750 (Post 10775586)
There was a recent touch and go on a soft wet grass runway on the Isle of man that resulted in the aircraft digging in and flipping onto it's roof. Try Googling M-GOLF and you should see the result of it.
https://www.google.co.uk/url?sa=i&ur...AAAAAdAAAAABAD

Well, there we are

ShyTorque 7th May 2020 21:44

I used to forbid my students on the Bulldog to even carry out a PFL to a “brown” ploughed field, in case the engine didn’t pick up. The undercarriage is fixed and there were cases of the aircraft flipping over on soft ground. With a low wing and a one piece canopy there’s every chance you would trapped. Latterly, the RAF Bulldogs were equipped with a belt cutter/escape hammer, but how much use it would be was open to conjecture.

Obviously, in a high wing aircraft with side doors you’re better placed.

421dog 7th May 2020 21:55

Seems to me that if that is the procedure recommended in the POH, maybe our betters have determined that that technique might improve outcomes.

In any event, the insurance implications of non-compliance seem daunting.

KRviator 7th May 2020 21:59


Originally Posted by 421dog (Post 10775796)
Seems to me that if that is the procedure recommended in the POH, maybe our betters have determined that that technique might improve outcomes.

In any event, the insurance implications of non-compliance seem daunting.

Not really, in an emergency, the PIC has authority to do what they feel is best at the time. I don't think any insurer is going to quibble over the gear up/gear down recommendation after the event.

421dog 7th May 2020 22:04

Not really, in an emergency, the PIC has authority to do what they feel is best at the time. I don't think any insurer is going to quibble over the gear up/gear down recommendation after the event.

try that in a Bonanza with/without flaps on a gear failure and try to get reimbursed if you guess wrong.

the POH is a required piece of kit for a reason.

megan 8th May 2020 01:09

Go to 1:30 to see why gear up is recommended, being a fixed gear 175 in this case they didn't have much choice. More likely to have a repairable aircraft as well rather than a write off.


Pugilistic Animus 8th May 2020 15:56

When I was training, we opened the door for forced landing practice.... well we didn't actually do that but it was part of the memory items so as I approached we said "door...cracked" and I then physically touched the door; this was In order to militate against the possibility being trapped


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