Originally Posted by
SFOtoBOS
Interesting example. How many radars are their onboard standard jets? I always assumed one (primarily intended for WX and terrain) and maybe two (TCAS, transponders). I would never have guessed a jetliner could fly without a working WX radar? Can they fly like that at night, still do ILS landings?
I am not even a flight simulator pilot, just a curious electrical engineer.
You don't need a wx radar to fly an ILS approach. There is one wx radar onboard a jet. We can fly without one, but it must be in the day with no TS or weather forecasted. I never take one at night, so I don't know what the MEL says, but I believe you can't fly at night without one, but that's a guess. Terrain is not what the weather radar is used for. We have a Enhanced Ground Proximaty Warning system that shows us ground terrain avoidance, using an internal database coupled with a ground doppler radar. It is totally separate from a weather radar.