11 April 1970

Apollo 13 is launched.

Apollo 13, NASA’s third crewed mission to the moon, launched on April 11, 1970. Two days later, on April 13, while the mission was en route to the moon, a fault in the electrical system of one of the Service Module’s oxygen tanks produced an explosion that caused both oxygen tanks to fail and also led to a loss of electrical power. The Command Module remained functional on its own batteries and oxygen tank, but these were usable only during the last hours of the mission. The crew shut down the Command Module and used the Lunar Module as a “lifeboat” during the return trip to Earth. Despite great hardship caused by limited power, loss of cabin heat, and a shortage of potable water, the crew returned to Earth, and the mission was termed a “successful failure.”

This photograph of the Mission Operations Control Room in the Mission Control Center at the Manned Spacecraft Center now Johnson Space Center, Houston, was taken on April 13, 1970, during the fourth television transmission from the Apollo 13 mission. Eugene F. Kranz foreground, back to camera, one of four Apollo 13 flight directors, views the large screen at front as astronaut Fred W. Haise Jr., Lunar Module pilot, is seen on the screen.

11 April 1970

Apollo 13 launches.

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The Apollo 13 mission was launched at 2:13 p.m. EST, April 11, 1970 from launch complex 39A at Kennedy Space Center. Apollo 13 Launch The space vehicle crew consisted of James A. Lovell, Jr. commander, John L. Swigert, Jr., command module pilot and Fred W. Haise, Jr. lunar module pilot.

The Apollo 13 Mission was planned as a lunar landing mission but was aborted en route to the moon after about 56 hours of flight due to loss of service module cryogenic oxygen and consequent loss of capability to generate electrical power, to provide oxygen and to produce water.

Spacecraft systems performance was nominal until the fans in cryogenic oxygen tank 2 were turned on at 55:53:18 ground elapsed time. About 2 seconds after energizing the fan circuit, a short was indicated in the current from 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, causing temperature and pressure to increase within cryogenic oxygen tank 2. When pressure reached the cryogenic oxygen tank 2 relief valve full-flow conditions of 1008 psi, the pressure began decreasing for about 9 seconds, at which time the relief valve probably reseated, causing the pressure to rise again momentarily. About a quarter of a second later, a vibration disturbance was noted on the command module accelerometers

11 April 1951

The Stone of Scone, the stone upon which Scottish monarchs were traditionally crowned, is found on the site of the altar of Arbroath Abbey. It had been taken by Scottish nationalist students from its place in Westminster Abbey.