The Atlas/Centaur-69 vehicle arrived aboard a C-5 Air Force transport plane from the General Dynamics plant, San Diego, on April 3. The Atlas stage was erected on Pad 36-B, Cape Canaveral Air Force Station, on April 4 and the Centaur stage was hoisted atop the Atlas on April 5. The vehicle was powered up to begin prelaunch testing on April 16.
On May 30, during a routine wet dress rehearsal test, a high-pressure helium line failed at the beginning of the test causing minor damage to the interstage adapter and delaying the target launch date until July 9. A second test was conducted on June 19, but due to a ground software problem, the test was halted at the T-31 second mark. The decision was made to conduct another retest, delaying the target launch date until July 17. The retest was accomplished on June 26.
On June 14, a simulated flight test was conducted. This check operated the vehicle's electrical and mechanical systems, verifying that they will perform as designed during the ascent to orbit. This was followed by a full countdown demonstration exercise, including the filling of the vehicle with its full complement of liquid hydrogen, liquid oxygen and RP-1 propellants. All countdown events were performed as they are on launch day up to first stage ignition.
A new payload fairing 14 feet in diameter, four feet wider than previous fairings, underwent final assembly in the Payload Hazardous Servicing Facility (PHSF) in the KSC Industrial Area. Fit checks, electrical tests and a mechanical verification to confirm that the fairing would open and separate from the vehicle properly during the ascent were conducted atop the vehicle at the launch pad. It was returned to the PHSF and prepared for encapsulation with the spacecraft.
[back to contents]The CRRES spacecraft arrived at the PHSF on March 23. Electrical checks and functional testing of the spacecraft were completed on April 20. During the first week of May, the canisters, designed for releasing the chemicals in orbit, were loaded with their respective elements and were placed aboard the spacecraft. There are eight small and 16 large canisters which collectively contain the elements barium, lithium, strontium and calcium.
On May 14, 3 days of spacecraft end-to-end compatability tests were performed between the CRRES satellite at KSC and the Air Force Consolidated Satellite Test Center (CSTC) in Sunnyvale, Calif. CSTC will be the control center for the spacecraft during the mission. Spacecraft commands, telemetry and data communications were verified.
The spacecraft was fueled with the hydrazine attitude control propellant on May 21 and transported to Launch Complex 36 for mating to the AC-69 vehicle on July 2.
[back to contents]Atlas Centaur launch operations will be conducted from the Complex 36 blockhouse by a launch team from General Dynamics, the vehicle's manufacturer. RP-1, a highly refined kerosene fuel burned by the Atlas, will be loaded aboard the stage 3 days prior to launch. The liquid oxygen used by the Atlas and the Centaur will be loaded aboard during the countdown, beginning at T-75 minutes. The loading of liquid hydrogen aboard the Centaur stage at T-43 minutes, running concurrently with the remainder of the liquid oxygen loading.
Since this is a NASA mission, the agency is accountable for mission success and government technical oversight as well as responsibility for supporting CRRES preflight preparations and testing. The NASA Lewis Research Center Project Manager is responsible for the administration and technical oversight of the Atlas I launch services contract.
A NASA launch manager from the Kennedy Space Center represents NASA interests during the launch vehicle checkout and preparations and serves as NASA's liaison with General Dynamics at the launch site. On launch day, he is located in the Mission Director's Center to monitor the countdown and the launch team activity and will provide a NASA final concurrence for launch to the General Dynamics launch director in the blockhouse.
[back to contents]The Eastern Test Range, an arm of the Air Force Eastern Space and Missile Center, will provide tracking support for the mission. Radar and communications will be relayed to NASA's Mission Director's Center and central telemetry facility on Cape Canaveral Air Force Station and to the Air Force CSTC control facility at Sunnyvale.
Tracking stations supporting the mission include the U.S. Air Force Tel-4 facility located at KSC, the Jonathan Dickinson Instrumentation Facility Jupiter Inlet in south Florida, the Antigua station in the Bahamas and the NASA radar at Bermuda. Also, two Advanced Range Instrumentation Aircraft (ARIA) will support over the South Atlantic off the coast of Africa to cover the second burn of the Centaur stage and spacecraft separation.
[back to contents]As with the Space Shuttle, weather observations and forecasting for the launch of AC-69 will be provided by the U.S. Air Force from the Cape Canaveral Forecast Facility. The weather criteria for the launch of expendable vehicles and the Space Shuttle are similar in many respects, but in some areas they are tailored to the unique characteristics of the expendable vehicle being launched.
On launch day, a total of nine upper air weather balloon soundings will be made starting at launch minus 6 hours. A weather reconnaisance aircraft will be deployed at launch minus 90 minutes. It will evaluate the weather downrange in the flight path of the vehicle and also assess any weather areas of concern that may be approaching the Cape.
A detailed weather briefing will be provided to the General Dynamics launch director and the NASA launch manager prior to retracting the gantry, again prior to fueling, and then immediately before launch.
[back to contents]