25 May 1973 13:00 GMT. Landing Date: 1973-06-22 13:49:49. Flight Time: 28.03 days. Flight Up: Skylab 2. Flight Back: Skylab 2. Call Sign: Skylab. Crew: Conrad, Kerwin, Weitz. Backup Crew: McCandless, Musgrave, Schweickart. Location of Capsule: Naval Aviation Museum, Pensacola, FL. Program: Skylab. Of note: Record flight duration. On the lighter side: On day 45 of the flight, ground control was startled when a female voice replied to their call. The mystified capcom continued the conversation for some time before realising that Garriot had pre-recorded a dialogue with his wife before the mission...after the flight, while shaving on earth, Lousma absentmindedly let go of his shaver, expecting it to float as he was used to... What went wrong: Crew had to conduct major repairs to get damaged station in operation. Astronaut flung into space during release of solar wing. High temperatures in station brought down by deployment of sunshade. Epic repair mission which brought Skylab into working order. Included such great moments as Conrad being flung through space by the whiplash after heaving on the solar wing just as the debris constraining it gave way; deployment of a lightweight solar shield, developed in Houston in one week, which brought the temperatures down to tolerable levels. With this flight US again took manned spaceflight duration record. Skylab 2 , consisting of a modified Apollo CSM payload and a Saturn IB launch vehicle, was inserted into Earth orbit approximately 10 minutes after liftoff. The orbit achieved was 357 by 156 km and, during a six-hour period following insertion, four maneuvers placed the CSM into a 424 by 415 km orbit for rendezvous with the Orbital Workshop. Normal rendezvous sequencing led to stationkeeping during the fifth revolution followed by a flyaround inspection of the damage to the OWS. The crew provided a verbal description of the damage in conjunction with 15 minutes of television coverage. The solar array system wing (beam) 2 was completely missing. The solar array system wing (beam) 1 was slightly deployed and was restrained by a fragment of the meteoroid shield. Large sections of the meteoroid shield were missing. Following the flyaround inspection, the CSM soft-docked with the OWS at 5:56 p.m. EDT to plan the next activities. At 6:45 p.m. EDT the CSM undocked and extravehicular activity was initiated to deploy the beam 1 solar array. The attempt failed. Frustration of the crew was compounded when eight attempts were required to achieve hard docking with the OWS. The hard dock was made at 11:50 p.m. EDT, terminating a Skylab 2 first-day crew work period of 22 hours. The Skylab space station was launched May 14, 1973, from the NASA Kennedy Space Center by a huge Saturn V launch vehicle, the moon rocket of the Apollo Space Program. Sixty-three seconds after liftoff, the meteoroid shield--designed also to shade Skylab's workshop--deployed inadvertently. It was torn from the space station by atmospheric drag. This event and its effects started a ten-day period in which Skylab was beset with problems that had to be conquered before the space station would be safe and habitable for the three manned periods of its planned eight-month mission.
When the meteoroid shield ripped loose, it disturbed the mounting of workshop solar array "wing" two and caused it to partially deploy. The exhaust plume of the second stage retro-rockets impacted the partially deployed solar array and literally blew it into space. Also, a strap of debris from the meteoroid shield overlapped solar array "wing" number one such that when the programmed deployment signal occurred, wing number one was held in a slightly opened position where it was able to generate virtually no power.
In the meantime, the space station had achieved a near-circular orbit at the desired altitude of 435 kilometers (270 miles). All other major functions including payload shroud jettison, deployment of the Apollo Telescope Mount (Skylab's solar observatory) and its solar arrays, and pressurization of the space station occurred as planned.
Scientists, engineers, astronauts, and management personnel at the NASA Marshall Space Flight Center and elsewhere worked throughout the first ten-day period of Skylab's flight to devise the means for its rescue. Simultaneously, Skylab--seriously overheating--was maneuvered through varying nose-up attitudes that would best maintain an acceptable "holding" condition. Because of the loss of the meteoroid shield, however, this positioning caused workshop temperatures to rise to 52 degrees Celsius (126 degrees F). During that ten-day period and for some time thereafter, the space station operated on less than half of its designed electrical system, in the partially nose-up attitudes, was generating power at reduced efficiency. The optimum condition that maintained the most favorable balance between Skylab temperatures and its power generation capability occurred at approximately 50 degrees nose-up.
The crew rendezvoused with Skylab on the fifth orbit. After making substantial repairs, including deployment of a parasol sunshade which cooled the inside temperatures to 23.8 degrees C (75 degrees F), by June 4 the workshop was in full operation. In orbit the crew conducted solar astronomy and Earth resources experiments, medical studies, and five student experiments; 404 orbits and 392 experiment hours were completed; three EVAs totalled six hours, 20 minutes.
Skylab-2 MANHOUR UTILIZATION
MEDICAL ACTIVITIES 145.3 HOURS 7.5 PERCENT
SOLAR OBSERVATIONS 117.2 " 6.0 "
EARTH RESOURCES 71.4 " 3.7 "
OTHER EXPERIMENTS 65.4 " 3.4 "
SLEEP, REST & OFF
DUTY 675.6 " 34.7 "
PRE/POST SLEEP &
EATING 477.1 " 24.5 "
HOUSEKEEPING 103.6 " 5.3 "
PHYSICAL TRAINING
& PERSONAL HYGIENE 56.2 " 2.9 "
OTHER (EVA) ETC 232.5 " 12.0 "
TOTAL: 1944.3 " 100 "
Skylab 2 Chronology - - 1972 July 18-19 - The first command and service modules designed for the Skylab Program were delivered by North American Rockwell.
The CSM arrived at KSC via the Super Guppy aircraft. Upon arrival, the CSM, which would be launched on SL-2, was installed in the Operations and Checkout Building to begin its checkout procedure.
- 1972 Nov 24 - Skylab debris situation reviewed.
The Skylab debris situation was reviewed with emphasis on the S-IVB stages of Skylab 2, 3, and 4. It was decided that the S-IVB for these missions would be deorbited into the Pacific Ocean on an early revolution. The deorbit would be achieved by controlled venting of the S-IVB, dumping propellants ...more...
- - 1973 February 27 - May 25 - Skylab 2 spacecraft transferred to Launch Complex 39B in preparation for launch. Launch Vehicle: Saturn IB.
The Skylab 2 spacecraft, mated to its launch vehicle, was transferred 27 February from the KSC Vehicle Assembly- Building to Launch Complex 39B in preparation for launch. The SL-2 space vehicle consisted of the following major components: an S-IB (the first stage); an S-IVB (the second stage, which comprised the propulsion stages); an IU; a CSM; and an SLA. The next five paragraphs trace the SL-2 from the arrival of the component parts ...more...
- - 1973 March 25-30 - The Skylab flight hardware successfully completed the first total mission operations sequence during the mission simulation and flight readiness test at KSC.
The test included the SL 2 astronaut crew participation in the simulated launches of SL-1 and SL-2, mission activation and operation, deactivation, data dump, and powerdown.
- 1973 Mar 28 - The USNS Vanguard, a part of NASA's Space Flight Tracking and Data Network, departed Port Canaveral, Florida, for temporary duty at Mar del Plata, Argentina.
The ship would provide a two- way flow of information and communication between Skylab and Mission Control Center in Houston via Goddard Space Flight Center. Upon completion of the Skylab Program, it would return to Port Canaveral. The Vanguard was originally designed to provide tracking and data acquisition for the Apollo flights. It played an important role in the Apollo Program.
- - 1973 May 23-24 - A design certification review was held for the revised Skylab 2 mission. Spacecraft: Skylab.
The review board determined that a 'Skylab parasol,' with a strengthened ultraviolet resistant material, deployed through the scientific airlock would be the prime method for the deployment of a thermal shield on the Orbital Workshop. A 'twin pole' thermal shield and a standup extravehicular thermal sail would be flown as backup methods. Following final assessment of mission readiness with favorable recommendations, a certification of flight worthiness for the new hardware was executed.
- 1973 May 25 - Skylab 2 Crew: Conrad, Kerwin, Weitz. Spacecraft: Apollo CSM. Payload: Apollo CSM 116. Mass: 19,979 kg (44,046 lb). Launch Site: Cape Canaveral. Launch Vehicle: Saturn IB. Duration: 28.03 days. Perigee: 425 km (264 mi). Apogee: 440 km (270 mi). Inclination: 50.00 deg. Period: 93.20 min.
Epic repair mission which brought Skylab into working order. Included such great moments as Conrad being flung through space by the whiplash after heaving on the solar wing just as the debris constraining it gave way; deployment of a lightweight solar shield, developed in Houston in one week, which brought the temperatures down to tolerable levels. With this flight US again took manned spaceflight duration record. Skylab 2 , consisting of a modified Apollo CSM payload and a Saturn IB launch vehicle, was inserted into Earth orbit approximately 10 minutes after liftoff. The orbit achieved was 357 by 156 km and, during a six-hour period following insertion, four maneuvers placed the CSM into a 424 by 415 km orbit for rendezvous with the Orbital Workshop. Normal rendezvous sequencing led to stationkeeping during the fifth revolution followed by a flyaround inspection of the damage to the OWS. The crew provided a verbal description of the damage in conjunction with 15 minutes of television coverage. The solar array system wing (beam) 2 was completely missing. The solar array system wing (beam) 1 was slightly deployed and was restrained by a fragment of the meteoroid shield. Large sections of the meteoroid shield were missing. Following the flyaround inspection, the CSM soft-docked with the OWS at 5:56 p.m. EDT to plan the next activities. At 6:45 p.m. EDT the CSM undocked and extravehicular activity was initiated to deploy the beam 1 solar array. The attempt failed. Frustration of the crew was compounded when eight attempts were required to achieve hard docking with the OWS. The hard dock was made at 11:50 p.m. EDT, terminating a Skylab 2 first-day crew work period of 22 hours.
- 1973 May 26 - Second manned day of the Skylab mission. Spacecraft: Apollo ATM.
The second manned day of the Skylab mission was focused on entry into the OWS and deployment of the Skylab parasol. The crew removed and inspected the docking probe and drogue. They then entered the ...more...
- 1973 May 27 - A Skylab Program Director's meeting was held to identify further actions required for the SL 2 mission and actions required for the SL-3 mission.
The following agreements were reached: The parasol installed on the OWS would not be jettisoned until a replacement thermal shield was on board, if a twin-boom thermal shield had not been deployed during the SL-2 mission. The twin-boom sunshade and the JSC sail would be retained in the OWS at the end of the SL-2 mission.
- - 1973 May 27 - June 22 - Skylab-2 crew began to activate experiments.
Following the successful deployment of the parasol, the Skylab-2 crew began to transfer and store equipment and activate experiments. On 29 May, everything in the OWS was turned on for the first time. The crew checked ...more...
- 1973 May 31 - Skylab issues reviewed.
During a Manned Space Flight Management Council telecon, four agenda items were discussed: an early launch date for SL-3; plans for an EVA solar array system repair; deorbiting of the Skylab cluster; and lengthening the SL-2 mission. The Council decided to go for a 27 July launch date, with the possibility of a further ...more...
- 1973 Jun 15 - A review was conducted at NASA Hq to determine whether the astronaut maneuvering unit and foot controller maneuvering unit could be safely used within the confines of the OWS.
It was concluded that the units could be safely operated, and approval was given for scheduling their use. Previously, a decision to operate the units had been deferred until a more thorough ...more...
- 1973 Jun 20 - Jettison the docking ring reaffirmed.
A recommendation to jettison the docking ring and probe assembly on SL-2 while the crew was unsuited was reaffirmed. Major considerations in arriving at the recommendations were that a suited landing was unacceptable, the additional risk of performing the operation unsuited was extremely low, and the crew had trained premission and in flight using the proposed timeline for an unsuited jettison of the docking ring and probe assembly.
- 1973 Jun 22 - Skylab 2 splashed down. Spacecraft: Skylab.
At 9:49 a.m. EDT, Skylab 2 splashed down in the Pacific Ocean 9.6 km from the recovery ship, U.S.S. Ticonderoga , and 1320 km southwest of San Diego. At 10:28 a.m., the crew and spacecraft were aboard the Ticonderoga. The objectives of the SL-1/SL-2 mission were to establish the Orbital Workshop in Earth orbit, obtain medical data on the crew for use in extending the duration of manned space flight, and perform inflight experiments. A summary assessment of the mission objectives indicated a very high degree of completion, particularly when the reduction in experiment time due to parasol deployment, solar array wing deployment, and OWS system anomalies were considered. Primary mission objectives were accomplished, and a majority of the assigned experiment-detailed ...more...
- 1973 Jul 30 - Skylab 2 mission summarized.
In a letter to the White House, NASA Administrator James C. Fletcher summarized the Skylab 2 mission. A situation that was bleak indeed on May 14, and for several days thereafter, improved ...more...
- 1973 Aug 1 - Skylab 2 postflight medical debriefings.
Skylab 2 postflight medical debriefings indicated the desirability of minimizing crew exposure to recovery ship motions for both crew reconditioning and postrecovery medical evaluations. In order to provide the Skylab 3 crew with this minimum exposure, mission duration was extended to 59 days. This allowed for a splashdown closer than 550 km of San Diego, and a crew stay time aboard the recovery ship of only 17 hours.
- 1974 Jan 24 - Significant repair and maintenance accomplishments of the three manned Skylab missions were reported. Spacecraft: Apollo ATM.
Significant repair and maintenance accomplishments of the three manned Skylab missions were reported. For the first 11 days, ground operations control kept the Skylab alive and allowed ...more...
Bibliography and Further Reading - Turnill, Reginald,, The Observer's Spaceflight Directory, Frederick Warne, London, 1978. ISBN: 0723220514. Good miniature encyclopaedia of space programs just before the shuttle started flying. More at amazon.com...
- Furniss, Tim, Manned Spaceflight Log, Jane's, London, 1986. ISBN: 0710604025. Summary of all manned spaceflights up to 1986. Pre-Glasnost, so many 'war stories' of Soviet manned spaceflight are not included. More at amazon.com...
- McDowell, Jonathan, Jonathan's Space Home Page, Harvard University, 1997-present. Jonathan McDowell's complete on-line listing of all objects orbited and over 20,000 rocket launches Accessed at: http://www.planet4589.org/jsr.html.
- Wilson, Keith T., Spaceflight, "EVA Log 1965-1997", 1998, Volume 40, page 85.
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