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There have been may cases of civilian, commercial, and military flights that have either been forced to or accidentally landed gear up.

When this happens I imagine that it can do serious damage to the runway it's landing on (assuming it's landing on a paved runway).

Does the runway need to be repaired after such a landing, if so, how long does it take, and how extensive are the repairs?

These are some of the different scenarios that come to mind:

  • Civilian aircraft doing a gear up landing, maybe about 1500-5000lb or so.
  • Commercial airliner doing a full gear up landing.
  • Commercial airliner with a single broken wheel.

How would runway repair be conduced in these scenarios?

enter image description here

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    $\begingroup$ Your new photo is Engineered materials arrestor system i.e. not normal runway construction. $\endgroup$ – ChrisW Jan 2 '15 at 8:47
  • $\begingroup$ … and the landing on the photo was a gear down landing. The three dug trails are behind the gears. $\endgroup$ – Jan Hudec Jan 4 '15 at 22:37
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Runways are usually made of several feet of reinforced concrete. Any damage to them after a wheels-up landing is superficial at best. Details depend on circumstances, but in general light aircraft will cause less damage. A full wheels-up landing is rather easy on the runway: The aircraft's fuselage and wing fairing structure are flexible and malleable, so it will buckle and bend until the local surface pressure is too low to cause more bending. To really damage a concrete surface you would need carbide tools, not sheet aluminum.

An unwheeled landing gear strut of an airliner is probably the worst scenario. The Airbus in the linked video had only a damaged nose gear, which carries a small fraction of the total load, and you will see in the close-up at the end of the video that the runway did not suffer. A similarly damaged main gear, however, will cut a groove.

All what is needed for repair is some fast-curing liquid for filling the nicks and scratches and some paint to repair the runway markings.

If you land a composite aircraft wheels-up, the concrete will act like sandpaper on the structure. The landing zone will be marked by white epoxy dust. A broom is all what is needed to put the strip back to its initial condition.

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  • $\begingroup$ Some runways are 4 feet thick, depending on the traffic, and even thicker, I think, at the ends. $\endgroup$ – rbp Jan 1 '15 at 18:43
  • $\begingroup$ I changed the photo in the original question. In your answer, you make it seem like gear up landings don't really damage runways very much. What about in the photo? And I've heard of special runways that actually are made of soft cement to help arrest a "runaway" airplane. $\endgroup$ – Keegan Jan 2 '15 at 6:05
  • $\begingroup$ What about asphalt runways, which are very common. (For example, Europe's busiest airports -- Heathrow, Frankfurt, Charles de Gaulle and Amsterdam Schiphol -- all have asphalt runways.) $\endgroup$ – David Richerby Jan 2 '15 at 10:18
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    $\begingroup$ @DavidRicherby: What is below the asphalt? I always thought that the asphalt is only the top coat, and below is reinforced concrete. $\endgroup$ – Peter Kämpf Jan 2 '15 at 15:24
  • $\begingroup$ @PeterKämpf I don't know. To add to the conclusion, Wikipedia describes some of Chicago O'Hare's runways as "asphalt", some as "concrete" and some "asphalt/concrete". $\endgroup$ – David Richerby Jan 2 '15 at 15:37

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