Orbital Pegasus - Manual (Page 77)

Release 7.0 Apr 2010 66
Pegasus User’s Guide
The impact on Pegasus performance associated
with the DPA will be based on the configuration
chosen and must be determined on a mission-
specific basis.
10.25.1. Dual Payload Adapter with 59 cm
(23 in.) Primary PA
Pegasus offers a DPA that supports primary and
secondary payloads in a non-load bearing
configuration. The DPA uses a structural cylinder
of variable length to support the primary payload
PA. The cylinder encapsulates the secondary
payload. The primary or upper PA is the standard
59 cm (23 in.) PA. This PA is attached to the DPA
cylinder using a 97 cm (38 in.) separation system.
The secondary payload is attached to the forward
end of the avionics structure via a 59 cm (23 in.) or
43 cm (17 in.) PA. Following separation of the
primary payload, the 59 cm (23 in.) PA is released
from the DPA cylinder. The secondary payload is
then released and pushed out of the DPA cylinder
by the action of the separation system's matched
springs. A separation tip-off and clearance
analysis is performed to ensure that the secondary
payload does not contact the cylinder during
separation. The price of the secondary PA is not
included in this nonstandard service (see Sections
10.25 and 10.26).
The volume available to the secondary payload is
limited by the height of the primary payload, the
height of the primary PA, and tip-off rates of the
secondary payload. The primary and secondary
payloads must share the 10 pass-through circuits
of the standard electrical interface capabilities of
Pegasus. The standard launch vehicle and
payload separation breakwire circuits provided by
Pegasus will be duplicated for both the primary
and secondary payloads.
The impact on Pegasus performance associated
with the DPA will be based on the configuration
chosen and must be determined on a mission-
specific basis.
10.25.2. Dual Payload Adapter with 43 cm
(17 in.) Primary PA
Pegasus offers a DPA that supports primary and
secondary payloads in a non-load bearing
configuration. The DPA uses a structural cylinder
of variable length to support the primary payload
PA. The cylinder encapsulates the secondary
payload. The primary or upper PA is the
nonstandard 43 cm (17 in.) PA. This PA is
attached to the DPA cylinder using a 97 cm (38
in.) separation system. The secondary payload is
attached to the forward end of the avionics
structure via a 59 cm (23 in.) or 43 cm (17 in.) PA.
Following separation of the primary payload, the
43 cm (17 in.) PA is released from the DPA
cylinder. The secondary payload is then released
and pushed out of the DPA cylinder by the action
of the separation system's matched springs. A
separation tip-off and clearance analysis is
performed to ensure that the secondary payload
does not contact the cylinder during separation.
The price of the secondary PA is not included in
this nonstandard service (see Sections 10.25 and
10.26).
The volume available to the secondary payload is
limited by the height of the primary payload, the
height of the primary PA, and tip-off rates of the
secondary payload. The primary and secondary
payloads must share the 10 pass-through circuits
of the standard electrical interface capabilities of
Pegasus. The standard launch vehicle and
payload separation breakwire circuits provided by
Pegasus will be duplicated for both the primary
and secondary payloads.
The impact on Pegasus performance associated
with the DPA will be based on the configuration
chosen and must be determined on a mission-
specific basis.