The payload will be installed in the orbiter April 28, 1999. The crew will conduct orbiter and payload familiarization activities over the next few days and then participate in a launch dress rehearsal on Thursday. On Tuesday, April 20, Standard Shuttle interface testing revealed that an electrical cable on the left solid rocket booster was not conveying necessary signals between the left aft segment and left forward segment integrated electronic assembly boxes. Troubleshooting efforts revealed that one connector on the cable needs to be replaced. Workers will replace the connector and retest it in the VAB tomorrow, accommodating a Friday morning Shuttle transfer to the launch pad.
Managers expect no impact to the target launch date.
On Monday, April 19, Discovery has been mated to the external tank and solid rocket boosters in Vehicle Assembly Building high bay 3. The Shuttle was powered today to support Shuttle Interface Testing that continues through noon tomorrow. The entire Shuttle stack is scheduled to move out to Launch Pad 39B Wednesday morning. Due to the additional work, managers now plan to transfer Discovery to the VAB on Thursday, but do not expect Discovery's arrival at the launch pad to be delayed. Orbiter aft and midbody compartment close-outs continue on schedule.