Originally Posted by
ORAC
The F-35 will get you lost
The JSF is designed to fly and fight against the most determined foe—even a foe capable of jamming or destroying America’s Global Positioning System satellites, depriving U.S. forces of their preferred way of knowing exactly where they are in the world. But the F-35’s independent “inertial” navigation gear—which determines the plane’s position by constantly computing starting point, direction, speed and time—is off by a few degrees. That’s just enough to make it useless in combat. “These errors prevent accurate targeting solutions for weapons employment in a GPS-denied environment,” the Pentagon warns.
A software fix is in the works, but “further flight testing will be required.” Again, that takes time and money.
As an aside, I wonder why the F-35 and F-22 do not use a Stellar-Inertial Navigation System to help avoid the GPS-denied problem?