Apollo 13 (as

Apollo 13 (as-508): Houston, We Have A Problem. Essay Apollo 13 (AS-508): Houston, we have a problem. The Apollo 13 mission was launched at 2:13 p.m. EST, April 11, 1970 fromlaunch complex 39A at Kennedy Space Center. The space vehicle crew consisted ofJames A. Lovell, Jr. commander, John L. Swigert, Jr., command module pilot andFred W. Haise, Jr. lunar module pilot. The Apollo 13 Mission was planned as a lunar landing mission but wasaborted en route to the moon after about 56 hours of flight due to loss ofservice module cryogenic oxygen and consequent loss of capability to generateelectrical power, to provide oxygen and to produce water. Spacecraft systems performance was nominal until the fans in cryogenicoxygen tank 2 were turned on at 55:53:18 ground elapsed time (GET). About 2seconds after energizing the fan circuit, a short was indicated in the currentfrom fuel cell 3, which was supplying power to cryogenic oxygen tank 2 fans. Within several additional seconds, two other shorted conditions occurred. Electrical shorts in the fan circuit ignited the wire insulation, causingtemperature and pressure to increase within cryogenic oxygen tank 2. Whenpressure reached the cryogenic oxygen tank 2 relief valve full-flow conditionsof 1008 psi, the pressure began decreasing for about 9 seconds, at which timethe relief valve probably reseated, causing the pressure to rise againmomentarily. About a quarter of a second later, a vibration disturbance wasnoted on the command module accelerometers. The next series of events occurred within a fraction of a second betweenthe accelerometer disturbances and the data loss. A tank line burst, because ofheat, in the vacuum jacket pressurizing the annulus and, in turn, causing theblow-out plug on the vacuum jacket to rupture. Some mechanism in bay 4 combinedwith the oxygen buildup in that bay to cause a rapid pressure rise whichresulted in separation of the outer panel. The panel struck one of the dishes ofthe high-gain antenna. The panel separation shock closed the fuel cell 1 and 3oxygen reactant shut-off valves and several propellant and helium isolationvalves in the reaction control system. Data were lost for about 1.8 seconds asthe high-gain antenna switched from narrow beam to wide beam, because of theantenna being hit and damaged. As a result of these occurrences, the CM was powered down and the LM wasconfigured to supply the necessary power and other consumables. The CSM was powered down at approximately 58:40 GET. The surge tank andrepressurization package were isolated with approximately 860 psi residualpressure (approx. 6.5 lbs of oxygen total). The primary water glycol system wasleft with radiators bypassed. All LM systems performed satisfactorily in providing the necessary powerand environmental control to the spacecraft. The requirement for lithiumhydroxide to remove carbon dioxide from the spacecraft atmosphere was met by acombination of the CM and LM cartridges since the LM cartridges alone would notsatisfy the total requirement. The crew, with direction from Mission Control,built an adapter for the CM cartridges to accept LM hoses. The service module was jettisoned at approximately 138 hours GET, andthe crew observed and photographed the bay-4 area where the cryogenic tankanomaly had occurred. At this time, the crew remarked that the outer skincovering for bay-4 had been severely damaged, with a large portion missing. The LM was jettisoned about 1 hour before entry, which was performednominally using primary guidance and navigation system.