Figure 6-21.-CPU-66/A computer components.
supersonic aircraft. T h e s e aircraft have
output devices, lead screw, and frame until the
operational limitations of 80,000 feet of altitude
microsyn is again in a null position. Thus, the
a n d Mach 2.5. The CPU-46/A consists of
angular rotation of the frame caused by the
pressure sensors, a computing system, an elec-
aneroid capsule displacement provides a change
tronic package, and output devices. The unit
in the synchro and encoder outputs.
receives pressure from the aircraft pitot-static
system and requires a 115-volt, 400-hertz power
CPU-46/A SUPERSONIC ALTITUDE
source. It provides altitude information, corrected
COMPUTER. --The CPU-46/A altitude com-
for static-pressure error, as follows:
puter (fig. 6-22) is used in high-performance,
·
Two separate analog signals for
positioning the remote AAU-19/A altimeters.
·
An encoded binary signal to the airborne
transponder for altitude reporting. The out-
put of the encoder must agree with the out-
put to the AAU-19/A to within ±20 feet. A
mechanical cam compensates for static-
pressure position error. Corrected pressure altitude
is computed and provided as output signals.
If the computer fails, the AAU-19/A altimeter
automatically reverts to a pneumatic standby
mode, and the altitude reporting encoder
deactivates. A standby flag appears on the
AAU-19/A display to advise the pilot of the
failure.
Figure 6-22.-CPU-46/A supersonic altitude computer.
6-21