- Joined
- Mar 23, 2005
- Messages
- 13,226
It's commonly an interface that is some variation on:
I want to be at X feet above my destination (last waypoint) Y miles before it, with Z fpm letdown. You tweak those variables, and then you get glide slope-like vertical guidance from the GPS. Really useful stuff. But, the big difference between that an an actual GPS approach is that the vertical guidance will happily run you into mountains. WAAS approaches, on the other hand, are carefully planned by the FAA, one at a time. They're also the only ones legal to fly in IFR/IMC.
I want to be at X feet above my destination (last waypoint) Y miles before it, with Z fpm letdown. You tweak those variables, and then you get glide slope-like vertical guidance from the GPS. Really useful stuff. But, the big difference between that an an actual GPS approach is that the vertical guidance will happily run you into mountains. WAAS approaches, on the other hand, are carefully planned by the FAA, one at a time. They're also the only ones legal to fly in IFR/IMC.