Monday, June 2, 2008

STS-91 (Discovery)

 1998-034A


STS-91 was the final US mission to Mir, recovering long-stay astronaut Andy Thomas. Veteran space station designer, former cosmonaut, and Mir program manager Valeriy Ryumin, following a strenuous weight loss program, joined the STS-91 crew to carry out a brief inspection tour of the Mir station. STS-91 also carried the flight test of the Alpha Magnetic Spectrometer (AMS), a particle physics experiment. Most crucially, the launch of STS-91 featured the first test of the Al-Li superlightweight external tank, which performed correctly.

The Ku-band TV system failed, so TV coverage of the docking was curtailed and science downlink from AMS was severely hampered. An r-bar rendezvous was followed by docking on Jun 5, using an improved APAS docking mechanism for ISS. As soon as the hatches were opened, Thomas became part of the Discovery crew. Ryumin floated in to Mir for the first time to begin his inspection. During his stay, the crew celebrated the moment he reached a career total of 365 days in space. The DCAM and PCG GN2 experiments were recovered from the Mir. The GMSF experiment was delivered. 12.5 CWC containers with 550 kg of water were delivered.

After undocking, a flyaround failed to spot flourescent gas being injected into Spektr by the EO-25 crew.

On Jun 9, a software problem in the experimental onboard GPS navigation system triggered a series of events which by Jun 10 led to the Shuttle systems computers being overloaded with error messages and failing to select the correct communications antennas, leading to a temporary loss of communication with the ground. Investigation led to software fixes and a decision to require further flight testing of the GPS system before it completely replaced the old TACAN navigation system.

Discovery remained in orbit carrying out work with AMS, which send down enough data to verify detection of anitprotons, but not enough to fully calibrate the instrument. The SHUCS communications experiment also ran into problems. On Jun 11, radio telescope observations of an RCS firing were used to study the effect of thruster plumes on the ionosphere.

OMS-2 mass was 114809 kg.


STS-91 
 

DateTimeEventOrbit  

1997 Oct 1   Tow to VAB/2 
1997 Oct 30   Tow to OPF/2 
1998 Apr 27   Roll to VAB/1 
1998 Apr 29   Mate to SLWT 
1998 May 2  0726  Roll to LC39A 
1998 Jun 2  2206:17  SSME ignition
 2206:24  Launch  
 2208:25  T+2:01 SRM cutoff 
 2208:27  T+2:03 SRB sep 
 2214:54  T+8:30 MECO 
 2215:13  T+8:49 ET sep  74 x 324 x 51.6 
 2250:34  T+44:10 OMS-2 1:45 51.5m/s 
 2252:20  T+45:56 OMS-2 C/O 90.18 239 x 326 x 51.6 
 2350:02  PLB Open 
1998 Jun 3  0147:42  OMS-3 raise peri 55s 26m/s 
 0148:36  OMS-3 C/O  91.09 326 x 329 x 51.6 
 1434:14  OMS-4 R Raise apogee 19s 4m/s  
 1434:33  OMS-4 C/O  91.24 327 x 343 x 51.6 
 2045   91.23 333 x 336 x 51.6 
 2123:32 OMS 5 Raise apogee 28s 13m/s 
 2124:00  OMS-5 C/O 
1998 Jun 4  0000   91.71 342 x 374 x 51.6 
 0600   91.70 342 x 373 x 51.6 
 1036  Rendezvous begins 
 1159:00  OMS-6 R burn 31s 7m/s 
 1159:32  OMS-6 C/O  
 1334:38  TI RCS 
 1354:43 MC1 
 1425:55 MC2 
 1442:55 MC3 
 1452:55  MC4 
 1645  Stationkeep at 10m 
 1650  Resume approach 
 1658:19  Docked with Mir SO 
 1712:00  Hard dock 
 1806   92.03 370 x 378 x 51.6 
 1828  Hatch open 
 2205Thomas part of STS crew 
1998 Jun 6  0600   92.03 370 x 378 x 51.6 

1244  RMS test, uncradle 
 1513  RMS recradle 
 1756  Spektr gas release test 
 1806  Release complete 
1998 Jun 8  0600   92.03 368 x 379 x 51.6 

1307 Hatches closed  
 1557 Begin undocking 
 1601:46 Undocking from Mir SO 
  Stationkeep at 75m on r-bar 
  Flyaround Mir to v-bar 
  Stationkeep at 60-80m on v-bar 
 1643s Spektr tracer gas experiment 
 1705s  Flyaround continues 
 1727:00  RCS Sep burn 1m/s 12s 
1998 Jun 9   RMS tests 
1998 Jun 11  0600   91.99 367 x 376 x 51.6 

1630:00  OMS-7 SIMPLEX, Lower perigee 12s 6m/s  
 1630:12  OMS-7 C/O   

2200  91.78 350 x 372 x 51.6 
1998 Jun 12  0629  91.78 350 x 373 x 51.6 

1418 PLBD closed 
 1652:25  OMS-8 DO 4:10 126m/s 
 1656:35  OMS C/O 
 1728  Entry interface 
 1800:24  Landed at KSC RW15 9d/19:53:54 
 1800:27  NGTD 
 1801:28  Wheels stop 
1998 Jun 13  0145Tow to OPF/2 

No comments:

Post a Comment

These Are Not My Beautiful Stories

  Summary: The chapters within are outlines for both future stories I’ve got planned (in the case that I never get around to writing them) a...