NASA Expendable Launch Vehicles Status Report: Deep Impact

MISSION: Deep Impact

LAUNCH VEHICLE: Delta II 7925

LAUNCH PAD: Pad 17-B Cape Canaveral Air Force Station

LAUNCH DATE: NET Jan. 12, 2005

LAUNCH WINDOW: 1:08:20 p.m. and 1:48:04 p.m. EST instantaneous

The launch of the Deep Impact spacecraft has been rescheduled for no
earlier than Jan. 12. During a review of launch vehicle hardware, it
was discovered that some components of the inter-stage adapter did
not receive proper heat treatment and must be removed and replaced.
The inter-stage adapter is located between the first and second stage
of the rocket. A Boeing engineer reviewing an “as-built” drawing of
the vehicle discovered the inter-stage had not been heat treated to a
revised higher specification.

The second stage will be removed from the vehicle on Dec. 15, the
inter-stage adapter removed on Dec. 16, a new inter-stage adapter
installed on Dec. 17, and the second stage re-installed on Dec. 18.

In processing activities at the Astrotech Space Operations facility
located near Kennedy Space Center, the high-gain antenna used for
Deep Impact communications with Earth has been installed. The solar
array panels have successfully completed an illumination test as a
final check of their performance. The flight battery associated with
the solar array panels has been installed. Fueling of the spacecraft
is scheduled to start on Dec. 19 and be completed on Dec. 22. Mating
to the payload attach fitting and upper stage booster occurs Dec. 29
– 30.

At Launch Pad 17-B, the loading of liquid oxygen aboard the first
stage for a leak check and a countdown launch team certification
exercise occurred Dec. 13. The vehicle guidance and control system
check occurs on Dec. 28. The Flight Simulation, a plus count that
exercises all of the systems on the vehicle as they will occur during
powered flight, is scheduled for Dec. 29.

The Deep Impact spacecraft is now scheduled to be transported to Pad
17-B on Jan. 3 and mated to the Boeing Delta II rocket. The Flight
Program Verification, the major integrated test with the Delta II,
occurs on Dec. 30. The Delta II payload fairing will be installed
around the Deep Impact spacecraft on Jan. 7.

The overall Deep Impact mission management for this Discovery class
program is conducted by the University of Maryland in College Park,
Md. Deep Impact project management is handled by the Jet Propulsion
Laboratory in Pasadena, Calif. The spacecraft was built for NASA by
Ball Aerospace and Technologies Corporation.