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STS-7 Day/Night Cycles
Launch: 20 Apr 83 1100 GMT
Ascending nodes move ~22.5 W [ [[Therefore]] cross equator @ ~same LCL time]
Every 31 orbits (~46 hrs) ~overlap (2 3/4[[degrees]] E of previous) [tracks ~60 nm's apart]
[[sketch]]
Orbital Period = 90 1/3 min (165 nm's)
[Note: shuttle will cross a given latitude
at the same local time on every orbit (this
time gets later by ~ 1 hr every 24 hrs)]

5 AUG -
telecon with MBB (Manfred, Tony, Bern)
Attitude Control System:
- in all modes except "inertial mnvr", if RF link
is dropped, SPAS will go to INRTL Hold. If SPAS
was in INRTL mnvr, SW remembers this, & goes into
"Bar-beque" mode, inertial rotation.
- "Null attitude" command = SPAS SW computes required
eigenaxis rotation, & mnvrs about that axis at
65 [[crossed out]] 5 [/crossed out] deg per sec [it recomputes eigenaxis every second,
& fires jets so as to maintain ~ .5 deg per sec]
- "STOP" cmd = sends SW to "HOLD" mode, which 1st looks
at rates, sees they're outside rate db [[?]], & fires