How many accelerometers are installed in an ins and what are the relative directions?
2x accelerometers and the positions are north south and east west.
The accelerometer is a pendulous device, when the pendulum swings off the null position signals are sent to what?
The torquer which restores the pendulum to the null position.
The purpose of the platform in a INS is to?
Keep the accelerometers level in all stages of flight to reduce error due gravity effects.
Earth rate compensation in a INS is ?
The platform is forced to tilt at the same rate as the earths rotation.
Aligning the the INS system, what 2 things are required ?
The accelerometers must be level and the platform must be orientated to TRUE north.
Limitations of the North pointing INS ?
Can not be flown within several hundred miles of the pole due the fact the system requirement needs to point North.
INS must not exceed ?
3xtime plus 3
3x10 hour flight plus 3 =33nm error max in 10 hour flight.
Max nav time without ground alignment in a single INS system is ?
10 hours, on flights more then 5 hours a contingency plan must be available in the event of a system failure
3 hours in CTA , 5 hours in a oceanic control area.
Requirements with 2 or more INS/IRS
5 hours in cta and 12 hours in oceanic control zones.
ATPL navigation INS