1980-F02
Block 5D-1 S-4 was launched on 1980 Jul 15 by Thor DSV-2U No. 59-2425 from SLC10W at Vandenberg. The Thor and Star 37XE stages separated successfully and placed the spacecraft in transfer trajectory, coasting to apogee where the Star 37S motor ignited. However, 9 sec into the burn contact with the spacecraft was lost and it was initally assumed the motor exploded. A later Thiokol document indicates a successful motor burn. An article in The Space Review by Wayne Eleazer reveals that an incident during launch preparations when the booster partly fell off the launch mount resulted in misalignment of the electrical connectors between stage 2 and 3. Stage 2 initially failed to separate, with the third stage firing and dragging along the second stage until the wiring ripped free, causing short circuits and errors in the guidance computer. The motor burn was completed but with the vehicle descending, and the spacecraft did not achieve orbit.
It is retrospectively known as Block 5D-1 F-5. The satellite carried the first SSH-2, a vertical temperature profile instrument with tighter filter bands and the SSR, a special sensor followon to the IFM experiment on S-2. The OLS sensor was OLS-5; OLS-4 was kept on the ground and later converted to OLS-11.
| DMSP 16538 (S-4, F-5) | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 1980 Jul 15 | 0222:11 | Launch by Thor DSV-2U | V SLC10W |
| 0224:44 | Thor MECO (T+2:33) | ||
| Fairing sep | |||
| 0224 | Thor sep, impact 2800 km SW VAFB | ||
| 0225? | Star 37XE burn | ||
| Coast | |||
| 0232? | Star 37S ignition at apogee, 820 km? | -4 | |
| 0232? | Guidance failure 9s into burn | -3700 x 820 x 98.7 | |
| 0232? | Stage 2 breaks free? | ||
| 0243 | DMSP/Star 37S reentry near 132W 9S? | ||
No comments:
Post a Comment