New to these forums.
My feeder is about 14 miles from a small rural airport with a surprisingly high General Aviation traffic count.
There are also several hospitals in range from which my feeder has captured numerous medical flights. Due to curvature of the earth and buildings, the signal is usually lost at about 80 to 150 feet AGL as it drops below the building height.
Most of these flights, when viewing / downloading KML files of their tracks, indicate “invalid” or “last seen near” when the final position report was obviously on final approach to one of the runways and a extrapolation inside Google Earth Pro of the KML track on the same bearing and slope intersects the ground right in the middle of the runway or at a hospital helipad.
However, the KML tracks downloaded from FlightAware in these cases appear to create an “airport” in the Atlantic Ocean off the west coast of Africa N00 00 000, W000 00 000 when I open these in a text editor or load them into Google Earth. This makes the Google Earth globe spin almost halfway around the world when these tracks are loaded.
- Is there a plan to add hospital and other heliports to the database to properly account for these off-airport flights?
- could the point tag in the KML track on these kind of flights just put the stick pin at the last known coordinates instead of make an “airport” stick pin in the KML in the middle of the Atlantic?
- If the last flight position heard was clearly on final approach to a runway, on a bearing within a couple of degrees of the runway and at an altitude trending a descent that extrapolation would clearly result in contact with the runway, is it possible to more quickly convert it from “en route” to an “estimated arrival”?
Many of the general aviation flights are pipeline / oil field leak patrols departing from and arriving at 7T7, end up showing as “en route” well over an hour after their last heard signal. It is obvious (well, to me, with some GIS processing experience and a few amateur radio APRS based high altitude balloon payload recoveries) that the aircraft is on the ground and has been there for a while.
Detecting a full stop landing in these circumstances should be possible to be assumed via algorithm when the aircraft was last heard from on final approach, hours before the track finally resolves now to either an estimated arrival or a “last seen near” end.
Back to the helicopter problem, a database of known heliports would provide much more accurate flight data on these. I pinpointed 3 in a few minutes manually by editing KML tracks downloaded from N911LL on a trio of flights and adding extended segments then zooming in on where those crossed to find the heliports.
The first leg is
which thinks it landed at Lea County Industrial Airpark (NM83). However, it actually landed at 32°45’44.50"N 103°11’11.93"W
This is close enough to NM83 for confusion to reign.
It then took off for Lubbock, which was recorded here:
There is a gap in the data which accounts for when the helicopter was clearly on the ground, based on altitude and terrain elevation as well as speed at the positions immediately before and after the gap in data.
Had there been a feeder on the Texas Tech campus on a mid to upper floor of the high-rise dormitories right across the street from this hospital, it would have gotten positions on the ground at Lubbock Covenant Hospital, at one of the two helipads at 33°34’36.45"N 101°53’24.81"W
However, the track did not break this into two separate flights, and combined the trip from Hobbs to Lubbock and Lubbock back to Seminole as a single flight.
ed to add after I made this post, the same helicopter flew the same route again, but it is now broken into 3 flights.
Seminole to Hobbs leg, origin and end at hospitals
Hobbs to Lubbock leg, origin and end at hospitals, with stop at KLBB apparently for fuel
Final leg, destination hospital at Seminole.
Most of the flights of this specific aircraft over the past few days, N911LL, have originated and ended at Gaines Memorial Hospital 32°43’14.33"N 102°39’17.92"W.
This might be a good specimen flight, cluster of helipads, and aircraft for people poring over how to code such a thing to work with.