Landing on displaced threshold

XcalibeR said:
I could be wrong, but I think one of the reasons a displaced threshold is not allowed for landing is that that part wasn't built for the force of landing planes. Or rather, it's not officially rated to the same weight threshold as the runway it's associated with. That means for a training aircraft, there shouldn't be any issue. But, "officially," there isn't any guarantee that the threshold won't collapse the instant you touch down.
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Typically that's the case where an airport operator has decided to stop maintaining a certain length of the runway up to the standards required to support landing certain aircraft. When my home field was resurfaced to concrete, the entire length, including the displaced threshold on the rwy 9 end, was built to the same standard. There are some airports in south Georgia that have lengthy displaced thresholds where it is pretty apparent that the runway used to cover the full length, but the operator just stopped maintaining the last 1000' or so except to patch a pothole or seal cracks. I can't really see it saving them a ton of money in the long run, so I'm not sure why some airports end up like that.
 
btw, "landing on displaced threshold" is exactly what you're supposed to do. The runway threshold is "displaced" by the appropriate markings, and normally you would land on it or a bit farther down.

I noticed I made this same semantic error in my first post, and wanted to clear it up, haha.
 
Just thinking outloud here, but some displaced threholds have the arrow for using it for T/Os but not landings. Could it be a differences in the bearing strength of the pavement? Not too sure that would be an issue with light aircraft.
 
granlistillo said:
Just thinking outloud here, but some displaced threholds have the arrow for using it for T/Os but not landings. Could it be a differences in the bearing strength of the pavement? Not too sure that would be an issue with light aircraft.
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Some of those that I've seen have a displaced threshold for either an obstruction or even noise abatement for landing purposes. For takeoff, they're just like the rest of the runway, and for landing rollout from the opposite direction, they're fine for that too.

Take GYR in AZ for instance, RW 3-21 is 8500, but 21 has about a 2100' displaced threshold that used to be all part of the runway. It's in excellent condition with a concrete hammerhead / hold area and asphalt. In the early '90s, the displaced threshold was added to 21 for purely noise abatement purposes, since the area to the N through E of the airport is now "noise sensitive" Litchfield Park, so there's really only 6400' available for landing on 21, pending you touch down on brick-one. However, landing on rollout on runway 3, it's fine to roll to the end, and you have the full 8500 available as well as on takeoff on 21. What a waste of good runway surface for landing........

http://maps.google.com/maps?hl=en&safe=off&q=KGYR&um=1&ie=UTF-8&sa=N&tab=il&start=0

[Photo credit, Mr. James Slater]
 

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Zondaracer said:
http://www.youtube.com/watch?v=A5ZLUP1Aroc

This KLM pilot clearly lands prior to the threshold and claims that it was "ok" because it was displaced for an ILS approach. He claims landing short saves the company fuel and taxi time (which sounds right), but I can't justify that as a reason to land before the threshold.
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Perhaps there are special procedures for the airport that allows for landing before the threshold? There were tons of tire marks before the threshold which would indicate that it happens a lot there.
 
Wow, this was brought back from the dead.


The displaced threshold at BFL was created for noise abatement only and the control tower has the authority (how, I don't know) to allow aircraft to land on it... which they consider a "full-length landing".
 
The term "full length landing" does not appear in any FAA publication.

If the airport manager wants that, then he can submit a NOTAM saying that. If it isn't important enough for him to do that, then it wouldn't be important enough for me to risk becoming involved in a problem to accommodate him.
 
one very misunderstood runway feature is the relocated threshold. looks like the displaced threshold, but the lines and arrows are yellow, not white.

this is a taxiway, and may not be used for takeoff or landing.

the center runway at pittsburg (KPIT) has this feature, and you will notice the majority of pilots use it like a displaced threshold.

i believe KSFO 1R is another runway with the relocated threshold.
 
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