Aircraft also have a maximum take-off weight, which is almost always higher than the maximum landing weight, so that an aircraft can weigh less upon landing due to burning fuel during the flight.
For example, on 3 February 2020, Air Canada Flight 837, a Boeing 767-300, suffered a rear tyre failure during take-off at Madrid–Barajas Airport on its way to Toronto, causing its left engine to catch fire.
The pilots managed to extinguish it by shutting the engine down, but as 767-300s are not designed for fuel dumping, it had to stay in a single-engine holding pattern for over 4 hours to burn fuel and achieve its maximum landing weight, while an SAF fighter reported minimal damage to the landing gear.
[3] Sometimes the emergency may be so pressing that the aircraft has no time to dump or burn fuel in order to achieve its maximum landing weight before touchdown; in that case, a risky overweight landing may be permitted.
[3] In other cases, the flight crew may fail to dump fuel when it still had the time to do so before landing, leading to fatal accidents such as Aeroflot Flight 1492 on 5 May 2019, where an apparently needlessly overweight landing turned into a crash that killed 41 of the 78 people on board.