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Go At Throttle Up

73 seconds to the end. At 0.678 seconds into the flight a puff of smoke is recorded jetting from the aft field joint of the right solid rocket booster.

71 seconds to the end. Cameras record eight more puffs of smoke emanating from the joint. The color of the smoke suggests the grease, joint insulation, and rubber O-rings are being burned and eroded by the intense heat of the burning propellant.

36 seconds to the end. The craft encounters the first of several high altitude wind shears. The wind shears cause relatively large deflections of the vehicle. These deflections are automatically countered by the guidance, navigation, and control systems of the engines. The number and intensity of the corrections recorded set new records for flights to that time.

15 seconds to the end. The main engines throttle up to 104 percent of their rated capacity. At this time, the first flickering flames coming from the solid rocket booster joint can be seen.

14 seconds to the end. The flame becomes a defined plume and the pressure sensors in the booster now detect a differential between the left and right booster. This is the first telemetry data confirming a leak is occurring.

9 seconds to the end. The flames suddenly change in shape and color as they breach the external fuel tank and begin burning the hydrogen therein. Telemetry from the fuel tank confirms a leak.

1 second to the end. The lower strut linking the Solid Rocket Booster and the External Tank is severed or pulled away from the weakened hydrogen tank permitting the right Solid Rocket Booster to rotate around the upper attachment strut. This rotation is indicated by divergent yaw and pitch rates between the left and right Solid Rocket Boosters.

0.88 seconds to the end. A circumferential white vapor pattern is observed blooming from the side of the External Tank bottom dome. This is the beginning of the structural failure of hydrogen tank that culminated in the entire aft dome dropping away. This releases massive amounts of liquid hydrogen from the tank and creates a sudden forward thrust of about 2.8 million pounds, pushing the hydrogen tank upward into the intertank structure. At about the same time, the rotating right Solid Rocket Booster impacts the intertank structure and the lower part of the liquid oxygen tank.

0.86 seconds to the end. White vapors appear in the intertank region. Within milliseconds there is a massive, almost explosive, burning of the hydrogen streaming from the failed tank bottom and liquid oxygen breach in the area of the intertank. At this point in its trajectory, while traveling at a Mach number of 1.92 at an altitude of 46,000 feet, the vehicle is totally enveloped in the explosive burn.

The end. The reaction control system ruptures and a hypergolic burn of its propellants occurs as it exits the oxygen-hydrogen flames. The reddish brown colors of the hypergolic fuel burn are visible on the edge of the main fireball. The vehicle, under severe aerodynamic loads, breaks into several large sections which emerge from the fireball. Separate sections that can be identified on film include the main engine/tail section with the engines still burning, one wing of the vehicle, and the forward fuselage trailing a mass of umbilical lines pulled loose from the payload bay.

NASA Space Shuttle Challenger Crew on January 28, 1986

  • Francis R. Scobee, Commander
  • Michael J. Smith, Pilot
  • Judith A. Resnik, Mission Specialist 1
  • Ellison S. Onizuka, Mission Specialist 2
  • Ronald E. McNair, Mission Specialist 3
  • Gregory B. Jarvis, Payload Specialist 1
  • Sharon Christa McAuliffe, Payload Specialist 2

May they rest in peace. Aloha!

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This page contains a single entry from the blog posted on January 28, 2003 9:09 AM.

The previous post in this blog was Moving Experience.

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