Landing Distance Available

[Jetset320]

ICAO's definition for Landing Distance Available (LDA) is " The length of runway which is declared available and suitable for the ground run of an airplane landing"

On an ILS equipped runway, what length would this be; the landing distance beyond the glideslope, or the landing distance beyond the threshold?

[esreverlluf]

I think you need to go back to the definition - it doesn't matter what nav aids are installed it's all about the length of bitumen - " The length of runway which is declared available and suitable for the ground run of an airplane landing". Don't overcomplicate it.:ok:

[westhawk]

From the threshold to the end of that part of the runway surface usable for aircraft rollout/taxi. This may include any displaced threshold area at the rollout end of the runway. Overruns and non-movement areas are not included in the published ALD*. Landing distance beyond glideslope intercept is also provided on airport charts, but how this information is used may vary somewhat.


*ALD is the acronym used in the USA to mean Available Landing Distance, perhaps because the acronym LDA is used to mean Localizer Directional Aid. For a multitude of reasons, many ICAO definitions, procedures and rules will take a long time to be adopted universally by all member states.

[Jetset320]

But certainly the "ground run" distance commences 1000ft down the runway and not at the threshold. Otherwise why have a 'screen height' over the threshold?

[esreverlluf]

Don't overcomplicate the thing - "ground run AVAILABLE".:=

[Max Angle]

Your roll out will certainly start well down the runway but all the manufacture supplied landing performance data will have the screen height taken into account so the published total distance can be used with no need correct.

[stormyweathers]

Thats what i think, but why do they publish this landing beyond glideslope? What use is this to us?

[kharmael]

Surely LDA is just that, it's the entire available distance, so if you want to call visual at 200ft on your ILS and then pole it down so your main wheels hit the numbers then that's how much you've got!

[Pull what]

Landing distance starts at the threshold and take off distance finishes at 35 feet-thats why