Salute!
Great stuff so far.
I thot TERCOM was a winner, and it, or its brother, seemed to do well certain applications like cruise missiles. I was flying the SLUF at the time and on one flight from Hicham to Guam I did not fully align the INS and flew for about 11 or 12 hours in the "doppler air mass mode" using predicted wind, the doppler and the air data computer for TAS. After all that time I was between 5 and 10 miles off, as the doppler was detecting ocean currents. Wasn't worried about getting lost as was with 5 other SLUF's and a KC-135 tanker, heh heh. Trust me, Amelia would have loved that!
Problem with TERCOM is it emits. True, the enema has to have a reciever underneath the missile flight path to detect it, but the less you emit the better.
If you can "see" a star in daylight, as this new system claims, we have a great solution to the "longitude" problem due to our cosmic, new clocks. Still have clouds and storms, but those stars can't be jammed and won't be put out of action at the initial strikes. BTW, my last job with Draper Lab was verifying performance of the Trident missile guidance system by flying it in an F-18 - yank the thing from a missile aboard the sub, fly it in a pod on the Hornet and gather/analyze data. It had a cosmic inertial, but just before launch they inserted the position of a star ( or two). After the stage quit and the "bus" floated free, the inertial shells about the gimballed sections rotated until a telescope could acquire the star. It then corrected the trajectory and the result was that a sub-launched missile from 4,000 n.m. away could put a nuke inside a soccer field. Gotta tellya, those guys at Draper were and still are very good.
Gums sends...