1999-017A
The Titan 4B returned to flight with core K-32, vehicle B-27, SRMU-8, a 402B model carrying the IUS-21 upper stage. SRM-1 burned and the IUS/DSP stack coasted to apogee. Then the SRM-1 motor was partially separated, but one connector stayed attached. Thermal tape wrapped on the connector made the separation system work incorrectly, a design problem that went back to the early days of IUS - it was just luck that it hadn't happened before. The SRM-2 exit cone was extended, but was fouled by SRM-1. The SRM-2 burn failed, stranding DSP 19 in transfer orbit. Orbital details were classified. DSP-19 was tumbling and it took several weeks to bring it under control.
The spacecraft was used for studies of high radiation dose effects and as a testbed for command software; it was shut down in 2008.
| USA 142 | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 1999 Apr 9 | 1701:00 | Launch by Titan 4B-27/IUS | CC LC41 |
| T+2:11 Stage 1 burn | |||
| T+2:26 SRMU sep | |||
| 1704:29 | T+3:26 Fairing | ||
| T+5:21 Stage 2 burn | |||
| T+5:22 Stage 1 sep | |||
| T+8:47 Stage 2 MECO | 188 x 718 x 28.6 | ||
| 1709:58 | T+8:56 Stage 2 sep | ||
| 1815:20 | T+1:13:27 SRM-1 | ||
| T+1:20:56 RCS-1 burn | 400? x 35000? x 28.5 | ||
| 2328:55 | T+6:29:44 SRM-1 sep partially | ||
| 2332:22 | T+6:33:08 SRM-2 burn | ||
| T+6:33 SRM-2 burn failed | |||
| 2334:15 | SRM-2 cutoff | ||
| 2341:52 | RCS depleted | ||
| 2354:59 | T+6:58 SRM-2 sep | ||
| 1999 Apr 10 | 0117:22 | IUS SRM-2 battery depleted | |
| 1999 Apr 30 | DSP under control | ||
| 2006 Aug | 593 x 34728 x 29.3 | ||
| 2008 Jul | Decommissioned | ||
