Proposed Search Location
I worked on flight profiles for avionics system tests at Naval Air Test Center (Pax River) for a couple years back in the late 1980s. Based on the reports I've heard, my analysis is as follows:
' ' Point S1 - Last ATC contact
txtStartLatitude = "6.9208"
txtStartLongitude = "103.5786"
' Point S2 – Contact, ADSB system (web track FR24)
txtStartLatitude = "6.9208"
txtStartLongitude = "103.5786"
' Point S3 - Last ATC contact, ADSB system (web track FR24)
txtStartLatitude = "6.9208"
txtStartLongitude = "103.5786"
' Sanga Mercur Oil Rig - known position
txtStartLatitude = "8.3667"
txtStartLongitude = "108.7026"
' Oil rig (Sanga Mercur Oil Rig) sighting report was:
' 265 - 275 bearing, high, minimal lateral velocity, on fire
' Plane had to be below 15,000 ft to not be on SGN ATC
‘
' Maintaining 65 deg course from S4, gliding @ 7:1 on fire?
' max range = 17.3 nm
' could have just reached the rig if turned toward it immediately, but
' rig was only 15 deg off to right so might have maintained course since
' that's where SAR would look (assuming SAR doesn't know about rig)
' Oil rig report: 265 - 275 bearing, high, minimal lateral velocity,
' on fire. Plane had to be below 15,000 feet to not be on SGN
' (Ho Chi Minh City) ATC as reported. Not sure how oil rig bearing was
' determined. If phone more accurate, but if just memory from rig true
' north, then maybe +/- 25 deg instead of +/- 5 deg.
'
' Point S4 - Location at oil rig sighting (assuming due west as reported):
txtStartLatitude = "8.3667"
txtStartLongitude = "108.4186"
' Maintaining 65 deg course, with 7:1 glide ratio.
' Not sure on glide ratio, 7:1 is for 747 (my memory).Also that's max
' with optimal AOA. Some time would have been used before attempting
' max glide and on fire (damage) would have probably reduced it.
'
' Point S5 - Final point (end of glide – crash/ditch) is at:
txtStartLatitude = "8.4885"
txtStartLongitude = "108.6825"
Obviously, there is some uncertainty in this position. I'm not sure about the FR24 system (I believe it extrapolates minute to mintute) Points (S2 & S3). I'm also not sure about the oil rig sighting bearing and distance (S4). Best guess on my S5 estimate uncertainty is +/- 15 nm. We probably have subs scanning gulf bottom by now (as well as ships) and they will probably find it soon.