Originally Posted by
EDML
Hmmm, the 737 MAX should have an IRS (Inertial Reference System) at least. It has bigger drift, therefore not suitable as the only source for long distance / time navigation. Usually it is backed up by other NAV systems (DME/DME or VOR/DME or GPS).
It will only give position data, though. Especially at the limits of the flight envelope it won't be able to replace air data.
Thism may be a repeat- but having problems withn link my apologies
IntroducingtheB-787.pdf
shows just how a INS can be an approx backup or judge
https://www.google.com/search?client...ducing+the+787