Orbital Pegasus - Manual (Page 33)

Release 7.0 Apr 2010 22
Pegasus User’s Guide
strength values in the table occur during powered
flight after the payload fairing has been jettisoned
and the Pegasus Stage 3 S-band antenna is
active.
Figure 4-13 lists the frequencies and maximum
field strength associated with RF emitters on the
L1011 carrier aircraft. The worst-case field
strength values in the table only exist while
Pegasus is mated to the carrier aircraft and all
L1011 emitters are active during captive carry or
ferry operations.
The maximum average electric field to which the
payload will be exposed due to Range emitters is
controlled to 20 V/m from 10 kHz to 40 GHz with
the exception of C-band frequencies used for
radar tracking. Between 5.4 and 5.9 GHz, the
maximum average electric field is 40 V/m.
During captive carry and powered flight,
uncontrolled RF emitters not associated with the
Range may cause the electric field at the payload
to exceed the levels caused by Range emitters.
Potential sources of significant RF fields will vary
depending on launch site.
Spacecraft radiated susceptibility testing limits
should be tailored to include the worst-case
composite of the electrical field strength during all
phases of integrated operations with the launch
vehicle and spacecraft on-orbit operations.
4.11. Payload Contamination Control
The Pegasus vehicle and all payload integration
procedures have been designed to minimize the
payload’s exposure to contamination from the time
the payload arrives at the field integration facility
through orbit insertion and separation. For each
mission, Orbital prepares a payload contamination
control plan that documents the provisions and
Figure 4-12. Pegasus XL RF Emitters and Receivers
Figure 4-13. Carrier Aircraft RF Emitters and Receivers