Document ID: chunk:federal_register_of_legislation:F2024L01024:front:0:p225
Version: federal_register_of_legislation:F2024L01024
Segment Type: other
Provision Reference: 
Character Range: 643128–646093

navigation unit is detected on the "aircraft" by indications from the Control and Display Unit (CDU) or by the status message from the corresponding sub‑system. By following the manufacturer's manual, the cause of the failure may be localised at the level of the malfunctioning Line Replaceable Unit (LRU). The operator then removes the LRU and replaces it with a spare.
2. 'Maintenance Level II'
The defective LRU is sent to the maintenance workshop (the manufacturer's or that of the operator responsible for level II maintenance). At the maintenance workshop, the malfunctioning LRU is tested by various appropriate means to verify and localise the defective Shop Replaceable Assembly (SRA) module responsible for the failure.
This SRA is removed and replaced by an operative spare. The defective SRA (or possibly the complete LRU) is then shipped to the manufacturer. 'Maintenance Level II' does not include the disassembly or repair of controlled accelerometers or gyro sensors.
7. B. 002. Equipment specially designed to characterise mirrors for ring "laser" gyros, as follows:
N.B.: SEE ALSO 7B102.
a. Scatterometers having a measurement "accuracy" of 10 ppm or less (better);
b. Profilometers having a measurement "accuracy" of 0.5 nm (5 angstrom) or less (better).
7. B. 003. Equipment specially designed for the "production" of equipment specified by 7A.
Note: 7B003 includes:
a. Gyro tuning test stations;
b. Gyro dynamic balance stations;
c. Gyro run‑in/motor test stations;
d. Gyro evacuation and fill stations;
e. Centrifuge fixtures for gyro bearings;
f. Accelerometer axis align stations;
g. Fibre optic gyro coil winding machines.
7. B. 102. Reflectometers specially designed to characterise mirrors, for "laser" gyros, having a measurement accuracy of 50 ppm or less (better).
7. B. 103. "Production facilities" and "production equipment" as follows:
a. "Production facilities" specially designed for equipment specified by 7A117;
b. "Production equipment", and other test, calibration and alignment equipment, other than that specified by 7B001 to 7B003, designed or modified to be used with equipment specified by 7A.
Note: 7B103.b includes:
a. Inertial Measurement Unit (IMU) Module Testers;
b. IMU Platform Testers;
c. IMU Stable Element Handling Fixtures;
d. IMU Platform Balance Fixtures;
e. Accelerometer Test Stations.
7. C.  Materials
None.
7. D.  Software
7. D. 001 "Software" specially designed or modified for the "development" or "production" of equipment specified by 7A. or 7B.
7. D. 002 "Source code" for the operation or maintenance of any inertial navigation equipment, including inertial equipment not specified by 7A003 or 7A004, or Attitude and Heading Reference Systems ('AHRS').
Note: 7D002 does not apply to "source code" for the "use" of gimballed 'AHRS'.
Technical Note:
For the purposes of 7D002., 'AHRS' generally differ from Inertial Navigation Systems (INS) in that an 'AHRS' provides attitude and heading information