Jonathan's Space Report No. 115 1992 May 19 ------------------------------------------------------------------------------ STS-49 Mission Report (Continued) --------------------------------- The third rendevous with Intelsat began around 1530 UTC on May 13 with an orbit adjustment maneuver. A software problem with the targeting code led to cancellation of the TPI (Terminal Phase Initiation) burn; at 1929 UTC a 'TI delay burn' was executed to keep Endeavour in the correct phasing for a later rendezvous attempt. The three spacewalkers, Pierre Thuot, Richard Hieb and Tom Akers, had already partially depressed the airlock to 5 PSI; they remained in the airlock during the delay. The TPI burn was finally executed at 2057.55 UTC and the depressurization was resumed at 2109. The hatch opened for the longest ever EVA at 2112; over the next hour (at 2119, 2153, 2203, and 2213) four mid course correction burns were made as Endeavour approached the Intelsat VI F-3 satellite; braking began at 2219. Intelsat was in a 355x370 km orbit at 28.3 deg. By around the same time the EVA crew had assembled the lower plane of the ASEM pyramid - three long poles forming a triangle attached to the top of the payload bay walls. Akers attached himself to the ASEM using a foot restraint; Hieb attached himself to the starboard sill of the payload bay; and Thout attached himself to the RMS arm which was operated from the cabin by Bruce Melnick. The Endeavour was then flown slowly towards Intelsat until at 2359.31 UTC on May 13 the three astronauts simultaneously grabbed the lower end of it and stopped its rotation. At 0045 UTC on May 14 Melnick started moving Thuot around the satellite and at 0122.57 the infamous capture bar was soft docked to the satellite by Hieb and Thuot. Thout then used an EVA power tool to hard dock the bar at 0132.55. Thout then exited the RMS and at 0147.41 the RMS grappled the capture bar grapple fixture allowing Hieb and Akers to release the satellite; it had been hand-held for 1h 48m. At 0300 UTC the Intelsat was hard berthed on the docking adapter to the Orbus 21S PKM, and the RMS released the capture bar. The grapple extensions on the bar were then removed and the PKM (Perigee Kick Motor) electrically activated and mated to the satellite. The three astronauts returned to the airlock. At 0440 UTC the first attempt to deploy the satellite failed. After two further failures and some rearranging of circuit breakers the satellite was sprung out of the payload bay at 0453.22 UTC. Hieb returned to the bay for cleanup tasks and the Endeavour moved away (a small burn at 0516 and a larger one at 0539). Finally at 0541 the airlock was repressurized for a total EVA time of 8h 29m. EVA-4 began at 2107 UTC on May 14, with Akers and Thornton in the payload bay. They completed assembly of the ASEM pyramid, demonstrated the Crew Propulsive Device, a gas gun similar to the HHMUs used on Gemini 4 and Skylab, and installed extra components on the MPESS pallet. The RMS was then used to unberth the MPESS from the payload bay and dock it to the ASEM pyramid. It was then undocked from the pyramid and at 0241 UTC on May 15 it was reberthed in the bay. The RMS ungrappled the MPESS at 0245 as the pyramid was disassembled. The crew returned to the airlock at 0437 and repressurization began at 0452, for an EVA time of 7h 45m. Deorbit from the 343 x 360 km orbit occurred at 1955 UTC on May 16 and Endeavour landed on runway 22 at Edwards Air Force Base at 2057.38 UTC on May 16. The drag chute was used for the first time to slow the craft on rollout. Next mission is STS-50/Columbia, the first flight of the Extended Duration Orbiter kit. STS-49 Statistics and Records ----------------------------- * First flight of OV-105 Endeavour * First dual active rendezvous (both Intelsat VI F-3 and OV-105 maneuvered to meet each other) * Dan Brandenstein gains most flight hours of any active US astronaut (789:05 in 4 missions) and most rendezvous experience (5 rv in 3 missions) and is the first person to fly 4 different Orbiters (Challenger, Discovery, Columbia, Endeavour, but so far not Atlantis). * Longest ever EVA (Hieb, Thuot, Akers: 08:29) * Kathryn Thornton holds record for longest EVA by a woman (07:45 beating Savitskaya's record of 03:35) * First 3-person EVA since 1973 and first ever in which all 3 were outside the spacecraft * First use of drag chute on landing for piloted spaceship * First manual in-orbit assembly of a rocket stage to a spacecraft (first such assembly in general was docking of Gemini 10 with Agena 5005, which was used to move Gemini 10 to a higher orbit). * 3 rendezvous in a single mission, joint record with Gemini 9 (1966), Soyuz T-15 (1986), and Progress M-7 (1991). * Thuot holds record for largest number of docking failures !! Pedantic Definition Corner: Spacewalks and Depress -------------------------------------------------- NASA reported that EVA-3 was the 100th EVA (Extra-Vehicular Activity) in history. You have to be a little careful about how you define EVAs. In 1969 Apollo 9 astronauts spacewalked in Earth orbit from a docked Apollo command module and lunar module; Scott and McDivitt EVA'd from the command module and Schweickart from the LM. Since these were separate spaceships with separate airlocks, albeit docked to each other at the time, I count these as two separate EVAs even though they were simultaneous, making STS-49/EVA-3 spacewalk no. 101. But actually I think a more interesting concept than EVA is 'depress work', time spent in a spacesuit under depressurized (vacuum) conditions whether inside or outside the shell of a spacecraft. NASA sort of implicitly agrees with me since it counts EVA time up to the moment of repressurization of the airlock, even if the crew spend an extra hour inside the airlock with the hatch closed. After all, what's dangerous (and hence in some sense significant) about EVA is that the astronaut is protected no longer by the pressurized spaceship cabin but only by a spacesuit - the spacesuit is their new spaceship. Logically extending this idea, I like to count cases where the spaceship cabin is depressurized even when the crew do not emerge. This is really pretty much the same as an EVA except for the 'E'. In Gemini and Apollo, the cabin was depressurized sometimes for 'Equipment Dumps' where the crew threw extra stuff out the hatch, e.g. lunar overshoes on Moon landings after all the moonwalks were done. These typically lasted 2 to 3 minutes, there were 9 of them. On the Skylab 2 flight, docking problems led to the crew having to suit up, depressurize the cabin, and disassemble their docking probe to repair it, before they could successfully dock their spacecraft. This depress is very poorly documented and not included in most lists of EVAs since the crew stayed in the cabin. Finally, the Soyuz-11 spaceship was unintentionally depressurized in June 1971 leading to the deaths of the crew. Not counting this last, the total number of occasions when crews worked in spacesuits in a depressurized environment (hmm, need an acronym here clearly - how about DP for depressurizations?), the total number of DPs by STS-49 EVA-3 is then 111 as opposed to 100 in the NASA list of EVAs. Launches ----------- The Palapa B4 satellite was launched by Delta at 0040 UTC on May 14 from Launch Complex 17B at Cape Canaveral. This was the 589th Thor launch, 209th Delta launch, and the 23rd Delta 2 launch. All 23 Delta 2 launches have been successful. Palapa B4 is a Hughes HS376 class comsat, owned by the Indonesian telecommunications agency PT Telekomunikasi, formerly PERUMTEL. Indonesia was the first Third World country with a domestic comsat system, as comsats have advantages for communications in a country made up of lots of islands. The Palapa series is summarized below. Satellite Type Launch Date Launch Vehicle Palapa 1 HS333 1976 Jul 8 D125 Delta 2914 Palapa 2 HS333 1977 Apr 15 D129 Delta 2914 Palapa B1 HS376 1983 Jun 19 STS-7 OV-099/PAM-D Palapa B2 HS376 1984 Feb 6 STS-11 OV-099/PAM-D Palapa B2P HS376 1987 Mar 21 D182 Delta 3920/PAM-D Palapa B2R HS376 1990 Apr 13 D194 Delta 6925 Palapa B4 HS376 1992 May 14 D209 Delta 7925 Current Shuttle Processing Status ____________________________________________ Orbiters Location Mission OV-102 Columbia OPF Bay 3 STS-50 OV-103 Discovery OPF Bay 2 Mod OV-104 Atlantis OPF Bay 1 STS-46 OV-105 Endeavour EAFB STS-49 ML/SRB/ET/OV stacks ML1/STS-46/ET VAB Bay 1 ML2/ VAB Bay 2 ML3/STS-50/ET VAB Bay 3 .-----------------------------------------------------------------------------. | Jonathan McDowell | phone : (617) 495-7176 | | Harvard-Smithsonian Center for | | | Astrophysics | | | 60 Garden St, MS4 | | | Cambridge MA 02138 | inter : mcdowell@cfa.harvard.edu | | USA | | '-----------------------------------------------------------------------------'