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Here's a scenario:

Just after Take-Off, there's an emergency on-board and pilot wants to land immediately. But, the weight of the plane wouldn't have decreased by large margins (usually 0.02*MTOW). Is the aircraft allowed to land with a weight more than Maximum Landing Weight?

What will happen if the plane tries to lands with a weight more than Maximum Landing Weight?

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    $\begingroup$ You might restrict your question to a specific type. Some short haul airliners may have a MTOW close (if not lower than) MLW. $\endgroup$ – Manu H Feb 17 at 14:00
  • $\begingroup$ If it "tries to land," what besides landing do you think might happen? The runway repels it so that it can't touch down??? I think what you're really getting at is, what happens after an overweight landing occurs, yes? $\endgroup$ – Ralph J Feb 17 at 17:53
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Most (all?) modern airliners are, in fact, certified to land at any weight up to MTOW if necessary, but if they do land at more than MLW then a special "Overweight/Heavy Landing Inspection" must be performed before the aircraft can be used again.

As this Boeing document states:

Overweight landings are safe because of the conservatism required in the design of transport category airplanes by FAR Part 25.

FAR criteria require that landing gear design be based on:

A sink rate of 10 feet per second at the maximum design landing weight; and A sink rate of 6 feet per second at the maximum design takeoff weight.

Typical sink rates at touchdown are on the order of 2 to 3 feet per second, and even a “hard” landing rarely exceeds 6 feet per second. Additionally, the landing loads are based on the worst possible landing attitudes resulting in high loading on individual gear. The 747-400 provides an excellent example. The 747-400 body gear, which are the most aft main gear, are designed to a 12-degree nose-up body attitude condition. In essence, the body gear can absorb the entire landing load. The wing gear criteria are similarly stringent: 8 degrees roll at 0 degrees pitch. Other models are also capable of landing at maximum design takeoff weight, even in unfavorable attitudes at sink rates up to 6 feet per second. This is amply demonstrated during certification testing, when many landings are performed within 1 percent of maximum design takeoff weight.

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