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Shuttle Endeavour Launch Status

February 11, 2000. 12:43 pm EST (17:43 UTC) Launch window was 2 hours and 10 min.

On Friday, February 11, 2000, Fueling of the external tank began at 3:49 am (EST) and entered into stable replenish mode at 6:37 a.m. At 8:02 am EST, the crew had their prelaunch breakfast and prepared to enter their launch and entry suits. At 9:09 am EST, the countdown clock came out of the hold at the T-minus 3 hour mark. At 9:15 am (14:15 UTC), the crew departed the Operations and Checkout Building (O&C) for Launch Pad 39A. By 9:30 am the crew was in the white room and began ingress into the orbiter. By 10:57 am the hatch was closed and locked for flight. The countdown clock was held at the T-minus 9 minute mark to resolve 3 minor technical issues relating to the cabin leak check supply pressure, a hydraulic recirculation pump and a L2 manifold tank heater. The count picked back up and the Orbiter Access Arm (OAA) was retracted at 12:36pm. The gaseous Oxygen vent arm was retracted at 12:41pm. A go for auto sequence start was given at the T-minus 20 second mark. Liftoff occured 12:43 (UTC 17:43).

On Thursday, February 10, 2000, Preparation continues on schedule today for the launch of Space Shuttle Endeavour this Friday at 12:30 p.m. EST. Replacement of the global positioning system box located inside Endeavour's crew module concluded yesterday and tests of the new unit are complete. The orbiter's onboard storage tanks were loaded with cryogenic reactants last night and no significant issues are being worked by the KSC launch team at this time. Today, Endeavour's three main engines will be prepared for propellant loading operations. The orbiter's communication systems will be activated this morning and this afternoon flight crew equipment late stow operations begin. The Rotating Service Structure will move to the park position at about 6:30 p.m., revealing the entire Shuttle for the first time since the last launch attempt. (Reference KSC Shuttle Status 2/10/2000)

On Wednesday, February 9, 2000, The launch countdown for mission STS-99 began on time yesterday at 5:30 p.m. EST, and final preparation for Friday's launch continues on schedule at Launch Pad 39A. A global positioning system box located inside Endeavour's crew module will be replaced following a failed self test this morning. Replacement efforts begin this evening and will not impact the launch date. The component supports SRTM payload operations in flight. This morning, routine tests of Endeavour's pyrotechnic initiator controllers confirmed that the safe and arm device indicator located in the left hand solid rocket booster's forward skirt is functioning as expected and is ready for launch. This was a confidence test for Shuttle engineers who yesterday completed inspections of a cable that supports the device. Inspections revealed only superficial scuffing to exterior tape and confirmed that the cable was intact. (Reference KSC Shuttle Status 2/09/2000)

On Tuesday, February 1, 2000, mission managers decided to delay the launch until no earlier than February 9, 2000 to give the launch team time to swap out Endeavour's Enhanced Master Events Controller (EMEC) #2 located in the orbiter's aft compartment.. A launch was last delayed August 29, 1984 on Discovery's STS 41-D flight due to a MEC. Engineers have not been able to reproduce the problem and are continuing their evaluation. Preliminary analysis and testing indicates a possible hardware problem within the unit. The unit weighs 65 pounds, is approximately 20 inches long, 13 inches wide and 8 inches tall. A spare is available at KSC and today workers are testing the replacement EMEC unit. (Reference KSC Shuttle Status 2/01/2000)

On Monday, January 31, 2000, tanking operations began at 4:10am EST and transititioned to stable replenish mode at 7:04 am EST. At around 8am EST a team was sent to the launch pad to troubleshoot a redundant power supply on the LH2 recirculation pump on the mobile launch platform. The ice inspection team was also at the pad inspecting the vehicle. The crew ate their preflight meal (Red Team breakfast and Blue Team lunch) and at 9:10am EST, suited up for flight. At 9:34 am EST the crew departed the Operations and Checkout Building for Launch Pad 39A. At 11:08 am EST, the hatch was closed and locked for flight. The countdown clock counted down to the T-minus 20 minute mark and was kept in a hold condition due to weather conditions. The launch team also investigatigated a potential problem with the onboard Master Events Controller (MEC) #2 Built In Test Equipment (BITE). The problem did not reoccur during additional testing. At 1:58pm EST, (18:58 UTC) NTD gave the go to pickup the count and countdown to the T-minus 9 minute mark and hold pending weather. At 2:08pm EST, the call was made to scrub due to weather constraints and enter into at 24 hour scrub turnaround. The new launch date was tentatively set for Tuesday, February 1, 2000 at 12:44pm.EST. Over the night, engineering teams will evaluate data from the Master Events Controller.

On Thursday, January 27, 2000, At Launch Pad 39A, work continues in preparation for Monday's launch of Shuttle Endeavour. This week, workers completed Shuttle ordnance installation and the aft compartment doors were installed yesterday. Endeavour's reaction control and maneuvering systems have been pressurized for flight and early flight crew equipment stowage is complete. Today at about noon, the STS-99 flight crew arrived at KSC to make final preparation for their upcoming flight. Over the next few days, crew members will review mission procedures, conduct test flights in the Shuttle Training Aircraft and undergo routine preflight medical exams. The launch countdown begins tomorrow at 5:30 p.m. and will be conducted in Control Room No. 3 in KSC's Launch Control Center. (Reference KSC Shuttle Status 1/27/2000)

On Wednesday, January 26, 2000, Aft compartment close-outs are complete. Replacement of the four payload bay camera assemblies is complete and retesting concluded today. While the payload bay doors are open, workers will clean the optics on the SRTM Attitude and Orbit Determination Assembly (AODA). Door closure is slated to occur tonight. Endeavour remains in the standard cold weather configuration with the reaction control system heaters powered up. The flight crew arrives at KSC tomorrow at about noon and the countdown clock starts Friday at 5:30 p.m. (Reference KSC Shuttle Status 1/26/2000)

On Monday, January 24, 2000, Over the weekend, engineers determined that four camera mounts in Endeavour's payload bay will be replaced with no schedule impact. Tuesday morning, the orbiter's payload bay will be opened and workers will remove and replace two camera assemblies from the forward bulkhead and two camera assemblies from the aft bulkhead. Analysis showed that the camera mounts were slightly yielding to the camera's weight. A strengthening modification has been implemented on the replacement units. (Reference KSC Shuttle Status 1/24/2000)
On Wednesday, January 5, 2000, The launch team is conducting a standard launch countdown simulation today in KSC's Launch Control Center. At the launch pad this week, workers are preparing to load propellant into Endeavour's onboard storage tanks. On Friday, engineers will conduct the Shuttle helium signature leak test. Leak checks on the orbiter's midbody umbilical unit are scheduled to occur next Wednesday. Terminal Countdown Demonstration Test activities with the flight crew are slated to occur Jan. 13 and 14.
(Reference KSC Shuttle Status 1/05/2000)

On Monday, December 13, 1999 Space Shuttle Endeavour rolled out of the Vehicle Assembly Building today at 7 a.m., headed toward Launch Pad 39A. Once at the pad, workers will begin routine launch pad validations. All three auxiliary power units will be hot fire tested tomorrow. The remainder of the STS-99 prelaunch work schedule is being reviewed due to the recent engine replacement and in order to accommodate STS-103 processing efforts. (Reference KSC Shuttle Status 12/13/1999)

On Wednesday, December 1, 1999 Workers in the OPF have completed wiring close-outs on Orbiter Endeavour and the payload bay doors were closed last night. Preparations are under way for Endeavour to roll to the Vehicle Assembly Building Thursday at about 10 a.m. The orbiter will be mated to the external tank and solid rocket boosters in VAB high bay 1Thursday night and managers plan to transfer the Space Shuttle to Launch Pad 39A Dec. 7. (Reference KSC Shuttle Status 12/01/1999)

On Thursday, October 7, 1999, with wiring inspections and repairs of Discovery and Endeavour nearing completion and similar work beginning on Atlantis, Shuttle program managers set new planning target launch dates for the next three Space Shuttle missions. (Reference KSC Shuttle Status 10/7/1999)

On Thursday, September 2, 1999, payload engineers have determined that the bent freon line associated with the SRTM payload will be repaired with a brace and replacing the line will not be necessary. The bent line was reported earlier this month by a technician working in that area. The freon line is part of a cooling system for some of the SRTM electronics. (Reference KSC Shuttle Status 9/2/1999)

On Thursday, August 19, 1999, workers removed the Shuttle Radar Topography Mission payload from Endeavour's payload bay and established access to the orbiter's midbody for planned wiring inspections. Inspections are expected to begin this weekend. With wiring inspection and maintenance plans now in place, implementation efforts are in progress across the Shuttle fleet. Shuttle managers are reviewing several manifest options this week and could establish the new target launch dates for 1999 as early as next week. Engineers must first define the time that will be needed to complete the fleet-wide wiring maintenance effort. Shuttle Endeavour currently remains slated for launch in early October. (Reference KSC Shuttle Status 8/19/1999)

On Thursday, August 12, 1999 Shuttle managers decided to delay the rollout of Shuttle Endeavour from OPF bay 2 to the Vehicle Assembly Building to conduct extensive wiring inspections and preventative wire maintenance in the orbiter's payload bay. In depth evaluation of payload bay wiring aboard orbiters Columbia and Atlantis revealed the potential for damaged wire to exist in Endeavour's payload bay. The additional work will delay the STS-99 launch to at least early October. Tomorrow, workers will begin preparations to remove the SRTM payload from Endeavour's payload bay to gain access to the lower cable trays that run the length of the orbiter's midbody. Once access is established, Shuttle engineers and technicians will begin necessary inspection and mitigation efforts. The impact of this delay and the unplanned wiring work needed on the rest of the Shuttle fleet is being assessed. (Reference KSC Shuttle Status 8/12/1999)

On Friday, July 16, 1999 Technicians have completed functional tests on Endeavour's landing gear. Payload bay close-outs continue and potable water servicing is ongoing. Leak checks of the crew cabin and external airlock are scheduled today. Preparations are under way to receive the SRTM payload into the OPF and then install it into the orbiter's payload bay next Tuesday. The orbiter/payload interface verification test begins next week. (Reference KSC Shuttle Status 7/16/1999)

On Tuesday, April 20, 1999, Modifications to Endeavour's radiator isolation valve are under way. Leak repair on the cold plate for the orbiter's power converter unit is ongoing. Orbiter docking system harness installation is in work and external airlock installation efforts conclude May 6. (Reference KSC Shuttle Status 4/20/1999)

On Thursday, March 18, 1999, Installation of Endeavour's three auxiliary power units (APU) concludes today when technicians install APU No. 2. Valve modifications on freon coolant loop No. 1 continue to go well. Next week, fuel cells No. 1 and No. 2 are being replaced and preparations to replace the left-hand orbital maneuvering system engine are ongoing. (Reference KSC Shuttle Status 3/18/1999)

On Thursday, February 25, 1999, modifications of Endeavour's freon coolant loop No. 1 continued to go well, with replacement of the left hand radiators now complete. The orbiter's forward reaction control system (RCS) will arrive in the OPF today for installation inside the orbiter's nose on Saturday. (Reference KSC Shuttle Status 2/25/1999)

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Developed under the direction of the NASA KSC Public Affairs Office
Author: Jim Dumoulin ( / NASA - Payload Operations
Last Updated: Thursday February 24 10:17:59 EDT 2000(J.Dumoulin)

A service of NASA/Kennedy Space Center Public Affairs Office, Joe Gordon Jr.,Director (