Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Cessna 172RG forced landing. Gear up or down if given the choice

Tech Log The very best in practical technical discussion on the web

Cessna 172RG forced landing. Gear up or down if given the choice

Old 7th May 2020, 08:53
  #1 (permalink)  
Thread Starter
 
Join Date: Jun 2000
Location: Australia
Posts: 3,973
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?
Centaurus is offline  
Old 7th May 2020, 11:32
  #2 (permalink)  
 
Join Date: Oct 2006
Location: Earth
Posts: 92
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.
LimaFoxTango is offline  
Old 7th May 2020, 12:32
  #3 (permalink)  
 
Join Date: Dec 2006
Location: The No Transgression Zone
Posts: 2,184
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.
Pugilistic Animus is offline  
Old 7th May 2020, 14:31
  #4 (permalink)  
Thread Starter
 
Join Date: Jun 2000
Location: Australia
Posts: 3,973
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.
Centaurus is offline  
Old 7th May 2020, 16:59
  #5 (permalink)  
 
Join Date: Apr 2008
Location: Nearer home than before!
Posts: 454
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
RVF750 is offline  
Old 7th May 2020, 21:21
  #6 (permalink)  
 
Join Date: Dec 2006
Location: The No Transgression Zone
Posts: 2,184
Originally Posted by RVF750 View Post
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
Pugilistic Animus is offline  
Old 7th May 2020, 21:44
  #7 (permalink)  

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 12,634
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.
ShyTorque is offline  
Old 7th May 2020, 21:55
  #8 (permalink)  
 
Join Date: Apr 2009
Location: USA
Age: 56
Posts: 215
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.
421dog is offline  
Old 7th May 2020, 21:59
  #9 (permalink)  
 
Join Date: Jan 2009
Location: Cab of a Freight Train
Age: 37
Posts: 496
Originally Posted by 421dog View Post
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.
KRviator is offline  
Old 7th May 2020, 22:04
  #10 (permalink)  
 
Join Date: Apr 2009
Location: USA
Age: 56
Posts: 215
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.
421dog is offline  
Old 8th May 2020, 01:09
  #11 (permalink)  
 
Join Date: Mar 2005
Location: N/A
Posts: 3,212
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.

megan is offline  
Old 8th May 2020, 15:56
  #12 (permalink)  
 
Join Date: Dec 2006
Location: The No Transgression Zone
Posts: 2,184
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
Pugilistic Animus is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.