My question: When taking off on a runway with displaced thresholds on both ends, is the runway length beyond the displaced threshold at the far end of the runway usable when calculating the Take-Off Run Available (TORA) or can it only be used to calculate the Accelerate-Stop Distance available (ASDA)?
Here's what prompts my question:
Here at MSP we have one runway - 4/22 - that has displaced thresholds at both ends. In this picture, you are looking right down the length of Runway 4 (View Large to be able to see the markings for the displaced thresholds):
Photo © Rick Resnik
The MSP airport diagram indicates that runway 4/22 is 11,006 feet long and that, when landing (due to the displaced thresholds) Rwy 22 has 10,018 feet available and Rwy 4 has 9,456 feet available. Here's the chart:
I believe (but am not sure) that the reason for the displaced thresholds on 4/22 at MSP is noise abatement (keep approaching aircraft higher over residential areas) and NOT because of physical obstructions beyond the ends of this runway.
Rwy 4/22 is usually used just once a day (except in rare wind conditions when the 12s or 30s can't be used) by NW flight 19 taking off for NRT . (And even this flight can use 12R/30L when the winds, temperature and load allow it). When flight 19 calls up ground control to request its push-back from the gate, the pilot will typically say something like: "We're going to need Runway 22 full length today." So, I also wonder if that "full length" request has anything to do with being able to use runway length beyond the far end's displaced threshold for the takeoff run.