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by sandworm101 2821 days ago
How do you account for winds and pressure differences, both of which will modify an approach. A plane may look like it is landing short, or to the left/right, when in fact the pilot is anticipating a change in wind as they drop in altitude.
1 comments

Good question. We've run into similar issues while developing a related feature that helps pilots perform a stable approach. Sometimes pilots were performing a circling approach to a different runway, and a naive approach to determining lateral deviations would have caused a nuisance alert.

For this particular system, the alerting threshold is only met when we've determined that the aircraft is "landing". As I mentioned in another comment, I'm vague about this point because it depends on the way the aircraft manufacturer has configured this state machine. Sometimes we use throttle position, altitude, speed above Vref, gear position, height above threshold, etc. You're correct that conditions can slightly modify an approach, but we're confident that we can nail down "we're landing" closely enough to mostly eliminate nuisance alerts.

What's your market? Light aircraft? airliners?
Our market right now is general aviation and business jets. I believe our biggest customer is the Cessna Citation Longitude (max takeoff ~40,000lbs). I noticed the NTSB abstract had some recommendations for inclusion and certification of a system on a broader range of aircraft. Larger aircraft are required to have similar safety-related systems such as terrain, reactive windshear, etc so this could be the next step.