Originally Posted by
Pilot1993
Just trying to clarify how PSA calculates VDP/PDP. Do you use the HAT rounded up to nearest 10 or nearest 100 feet and then divide by 300 to get the distance? What about for time, HAT rounded to nearest 10 or nearest 100 and then 10% for how many seconds to subtract?
Thanks for the help!
If it is a missed approach based on distance (DME), take the HAT and divide by 300. That will give you the distance from the runway.
If it is a missed approach based on time, take the HAT and divide by 10 (if it is 480, make it 48). Then take that number, and subtract it from the time from the FAF to the MAP. So if the time for the MAP is 3:52, and the HAT is 480, then subtract 48 from 3:52.
These are just rough estimates. We round up our precision and nonprecision approaches differently, which changes the HAT. This will be taught in ground school. I don't expect you to know exactly how PSA does it for the interviews.
More importantly, know what it means and why you use it. I honestly don't care if you know the math perfectly, but if you can tell me why you would use it and what it tells you, that is the important thing.
I also don't expect you to know anything company or ops spec specific. Just generic and FAR's. (For instance, different companies have different rules for takeoff alternates. I know exactly how several airlines teach it, but we just test based on the FAR. (hint: 121.617).