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Modern commercial aircraft are certified to be able to land at any weight providing that the runway is long enough. The "overweight landing" QRH procedures for the 734 and A320 are correspondingly quite short, referencing mainly the approach reference and target speeds and adjusting for wet/contaminated surfaces.

This video (which by the way, deserves repeated watching - there is just so much to look at, e.g. the vortexes high above the wings and from the flap outboard trailing edges) unfortunately is clipped from shortly after the emergency response crews arrive until the aircraft vacates under its own power.

This made me curious as to how the decision to taxi clear is made. Are there QRH/SOPs for this, either the operator or the airport?

My guess is that the fire fighters will check the bogies for any sign of fire and, coupled with the crew checking EICAS and the wheel and tyre temperatures and pressures, make a joint agreement that it is safe to vacate.

Following vacating, would the QRH/SOP be to stop when clear and allow extra time for cooling (which could be a long time) or taxi to the stand?

Wouldn't taxiing to the stand increase the risk of a fire starting even if there was none after it had stopped on the runway?

And that video, oh, watch it again.

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The answer very much depends on the operator and type of aircraft (or rather its manufacturer).

First of all, overweight landing would normally be performed for the following scenarios:

  • Medical emergency on board that requires prompt medical attention
  • Any fire/smoke that cannot be extinguished/ventilated
  • QRH dictating "Land at the nearest suitable airport"
  • Any situation where safety might become further degraded by prolonged flight

It's hard to list all the situations here, and most of the time the Captain will have to make a decision whether to do an overweight landing or not.

Having made the decision to perform an overweight landing, the crew needs to take into consideration the following items:

  • Runway length available - landing at significantly higher weight than MLW increases landing distance substantially
  • Missed approach climb gradient - this might be a problem at airports with high terrain nearby
  • Reduced landing flap - normal landing flap speeds at higher than MLW might be too close to Vfe (maximum speed for the selected flap setting)
  • Required brake cooling - if heavy braking is required to stop within the required landing distance available, then it's best to vacate the runway and have fire services check the brakes and tires. Fuse plugs might have melted and tires might have deflated. Subject to all clear from the fire services, aircraft might taxi to the stand, have the chocks set and wait there with brake released for a while.
  • Overweight autoland is normally not recommended, as the autopilots are not certified for this.

After an overweight landing, an inspection is required by engineers to make sure there are is no structural damage on the aircraft, particularly its landing gear and the skin. According to my knowledge, the overweight landing inspection is just a bit more thorough walkaround by the engineer, provided the overweight landing wasn't a hard landing. If it was a hard and and overweight landing combined, the aircraft is likely grounded for a while, as more detailed inspection is required.

All Part 25 (FAR 25, CS 25) aircraft are certified to be able to land with sink rate of 600 ft/min (10 ft/s) at MLW and 360 ft/min (6ft/s) at MTOW, so unless you do a particularly poor landing when overweight, there should be no structural damage, even when landing straight away after a takeoff at MTOW.

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The whole aircraft would be checked for structural damage, and the runway would be inspected as well.

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    $\begingroup$ Answers here are better received if you can provide some source for what you're saying -- either personal experience or a reference to something authoritative. In the case of this answer, the "runway would be inspected" part of it is more wrong than right. In many cases, you could land substantially overweight and if there was no declaration of an emergency, the airport would neither know nor care that you did. (The runway can't tell what the max certified landing weight of your aircraft is.) $\endgroup$
    – Ralph J ♦
    Commented Jul 1, 2017 at 3:02

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