cjh@csin.UUCP (Chip Hitchcock) (09/12/83)
My understanding (from ATC visits in the mid-70's, when I was working on my instrument rating) is that while commercial transatlantic aircraft have the equipment to maintain contact with ATC (i.e., low-frequency non-(line-of-sight) radio) and relatively precise navigation equipment (e.g. inertial, LORAN) they don't actually show up on radar for most of the flight; instead, they are told to maintain path, altitude, and speed (specific mention was made of a total of 5 traffic lanes with 15-minute separation between aircraft, with the lanes mostly one-way (reversed 2x daily) in between the coasts. Transpacific flights would obviously vary widely with destination (there aren't any floating radar stations between LA and Honolulu (yet) but much of an Anchorage-to-Seoul flight would be within "sight" of land). From the descriptions published in non-technical sources, it appears that KAL 007's nav equipment may not have had any external-reference readout---it said "you're on course" rather than "you're at lat X lon Y". So it's \possible/ that neither the pilot nor Japanese control actually knew where the plane was.