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Suppose you are flying an aircraft with retractable gear and have to make an emergency landing on that big "flat" stretch of grass up ahead and have only one shot at it, what's better, do it with wheels down or up.

Obviously, if the ground is flat enough, wheels down may be great and may even let you recover your aircraft basically undamaged. However, hitting a rut or other obstacle with the gear could have some rather unfortunate consequences.

That left me wondering which is better, dropping the gear and hoping for the best, or a controlled belly landing. (Also hoping for the best!)

I also wonder what, if any, instruction is given on this situation during flight training.

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    $\begingroup$ I'd say that almost always gear down is better, I'd rather rip the gear off than nose over in that rut or ditch. GA landing gear is remarkably strong. $\endgroup$ – Ron Beyer Aug 3 '17 at 14:44
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    $\begingroup$ From a glider point of view : during an outlanding, the only thing between my spine and the rocks hidden in the grass are my pants, a worn-out cushion and 5mm of plastic. I will always chose to add a wheel under all that. $\endgroup$ – Quentin Aug 3 '17 at 14:47
  • $\begingroup$ Also, from having landed many times on flat stretches of grass or dirt (generally but not always actual airports), that flat stretch of grass could be perfectly suitable for a gear-down landing and a subsequent takeoff. Landing with gear up eliminates that possibility. $\endgroup$ – jamesqf Aug 3 '17 at 18:44
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There are various factors here:

  1. Gear acts as a speed brake, in some emergency situations if you need the added drag as you approach the field (to make the field) a gear down situation may be called for regardless of ground condition. On the flip side if the field is on the edge of gliding distance you may want to keep the gear up to improve glide. This is a judgement call during the emergency.

  2. Gear will provide you limited steering on the ground which for what ever reason you may need. In a gear up situation you are sliding to a stop.

  3. Gear will provide you brakes, if the field is short you are going to want this option.

  4. If something is critically wrong with the plane and you need to do an emergency gear deploy there may be no time during the emergency.

Like anything, it depends and it will be a situational decision with merits to both aspects. You should consult the POH for your air frame as they will most likely have check lists for both scenarios.

For example in a Piper Arrow they offer a checklist of a gear up emergency specifically:

Gear up emergency landing:

In the event a gear up landing is required, proceed as follows:

(a) On aircraft equipped with the backup gear extender, lock emergency gear lever in "Override Engaged" position before airspeed drops to 115 mph to prevent landing gear from inadvertently free falling.

(b) Flaps as desired.

(c) Close throttle and shut off the master and ignition switches.

(d) Turn the fuel selector valve to OFF"

(e) Contact surface at minimum possible airspeed.

Here is what happens in a small plane when the gear collapses on a grass field. A gear up landing is not an automatic hull loss, in many cases they can be repaired. Considering the age and use level of most of the countries GA fleet you may be surprised to find out just how many planes have actually been through a gear up landing.

The only time that I know of where gear up is the only option is a water ditching. For that matter you are not going to water ditch a fixed gear plane.

I was always instructed during my training that ditching gear down (or with a fixed gear) in water was not really viable. There seems to be some info indicating that there is little data to support this. Of course you will find endless debate on the internet about it and some answers that fail to provide sources. Some of the misconceptions may be fueled by what happens when a float-plane digs in on landing.

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  • $\begingroup$ you say that "you are not going to ditch a fixed gear plane" however there are many cases where pilots have done just that, and the plane did not flip or cartwheel on the surface. In fact one recent one, on Lake Ontario, resulting in both occupants being rescued by boaters in the area, while the plane antennas stayed above the surface thanks to lotsa air in the fuel tanks. So is this your opinion, or experience, or do you have some aggregated statistics? $\endgroup$ – mongo Aug 3 '17 at 17:32
  • $\begingroup$ I had 2 different flight instructors give me this info. Im not saying it cant be done and Im sure there are successful cases but my flight instruction has always been, runway->green->brown->trees and avoid water in a fixed gear at all costs. $\endgroup$ – Dave Aug 3 '17 at 19:44
  • $\begingroup$ there are lots of flight instructors, with lots of opinions, many of them excellent. However, those flight instructors have varying experience, and some have extensive knowledge or first hand experience, and some repeat what they have heard, read and believe. One thing anyone can do is to look at the database of accidents and examine SE fixed gear ditching outcomes. Me? If I had the choice of steep granite or shallow warm water near boaters, in a C172 or C172, I would go for the bath. $\endgroup$ – mongo Aug 3 '17 at 20:22
  • $\begingroup$ Here's a report on a Cessna Caravan that ditched in 2013 aerossurance.com/news/ntsb-report-2013-c208-ditching The C208 is fixed gear, 8500# single engine turbine aircraft. $\endgroup$ – mongo Aug 3 '17 at 20:33
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First, the official guidance is the POH. After all the manufacturer knows his equipment best.

Second, shearing off wings and gear consumes energy. The trade off is whether control can be maintained as long with the gear coming off. On the other hand, at the speed you are touching down at, control (at least aerodynamic) will be lost pretty soon. Discretion on the part of the pilot is a function of his training and his ability to reason through his situation.

With respect to instruction, the standard practice is to cover emergency procedures on an initial aircraft checkout. My critique sheet for lessons has boxes ticking off items, and off field, water, and other emergency landings, engine out or with power are covered.

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