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Pegasus user’s guide – Orbital Pegasus User Manual

Page 24

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Release 7.0

Apr 2010

13

Pegasus User’s Guide

the separation distance between the two
bodies.

(2) At payload separation +300 seconds, the

launch vehicle begins a “crab-walk” maneuver.
This maneuver, performed through a series of
RCS thruster firings, is designed to impart a
small amount of delta velocity in a direction
designed to increase the separation distance
between Pegasus and the payload. The
maneuver is terminated approximately
600 seconds after separation.


At the completion of the C/CAM, all remaining
nitrogen and/or hydrazine is depleted.


4. PAYLOAD ENVIRONMENTS
The following subsections present the maximum
payload environment levels during Pegasus
captive carry and powered flight. The acoustic,

vibration, shock, and acceleration environments
presented below apply to the launch vehicle with a
single payload using either the 38" or 23" payload
adapter. The payload environments associated
with the use of alternative separation systems, a
nonseparating payload interface, or multiple
payload attach fittings will differ from those
presented below.

The electromagnetic radiation and thermal
environments presented below apply to all launch
vehicle and payload configurations.

4.1. Design Loads
The primary support structure for the spacecraft
shall possess sufficient strength, rigidity, and other
characteristics required to survive the critical
loading conditions that exist within the envelope of
handling and mission requirements, including
worst-case predicted ground, flight, and orbital

Figure 3-6. Typical and Recent Pegasus Orbital Accuracy