Steely-Eyed Missile Man

The words “Steely-Eyed Missile Man” are the highest compliment at the National Aeronautics and Space Administration. Starting with the legendary John Aaron, they are given out to a person who has shown that they can make the correct call under the highest possible pressure, with lives on the line.

Today is the 37th anniversary of the day that NASA engineer Jenny M. Howard went to work an ordinary mortal and came home a member of that most elite of scientific fraternities.

July 29, 1985 was the backup launch day for STS-51-F. It had been originally planned for July 12, and in fact scrubbed at T-3 seconds, the engines automatically powering down after the Redundant Set Launch Sequencer noticed a sluggish power-up sequence in the center engine. On-pad RSLS aborts were a common experience in the early years of the Space Shuttle program.

 A few hours before launch, Jenny Howard rolled into the parking lot at Johnson Space Center while over fifteen hundred kilometers away, a sleeping white dragon shed water vapor on its roost at Kennedy Space Center. Emblazoned on her wing with the legend Challenger, she was on this day the darling of the Space Shuttle program, about to embark on her eighth space flight. For nearly two years, she had been the workhorse of the Space Shuttle program as elder sister Columbia underwent a badly needed refit and junior sister Discovery slowly worked through her teething troubles. It was a muggy day on the Florida coastline, and no one had any idea that in just six short months, the space shuttle Challenger would forever have the word “disaster” appended to her name, bursting apart in a flower of expanding water vapor and shattered lives and dreams.

Aboard, settling in for their flight were pilot Roy Bridges, mission specialists Karl Henize, Story Musgrave, Tony England; payload specialists Loren Acton and John-David Bartoe, commanded by veteran astronaut C. Gordon Fullerton. Fullerton had four flights in a Space Shuttle under his belt. Flying Approach and Landing Test missions 2 and 4 on Enterprise under the command of Apollo 13 veteran Fred Haise, Fullerton had also previously flown as pilot on Columbia’s STS-3, commanded by Skylab astronaut Jack Lousma.

The Shuttle carried two payloads of decidedly unequal importance. Spacelab 2, which carried an experimental infrared telescope and a plasma physics package, was the prime payload and the one that would carry out the virtual totality of the shuttle’s mission. It also carried two small clutches of soda cans, each manufactured by the major rivals in the Cola Wars, Coke and Pepsi. After the flight, the astronauts revealed that they preferred Tang, which could be made with chill water supplies aboard the craft, as opposed to the unrefrigerated soda.

The Eighties.

In her engine bay, Challenger carried three of forty-two RS-25 Space Shuttle Main Engines that were built for the Space Shuttle program. These three engines had flown together on Challenger’s last two missions, STS-51-G and STS-51-B. The Left engine was 2021-6, installed in Challenger for STS-41-G after being used for the first time in Discovery’s maiden flight, STS-41-D. Engine 2020-6, was first installed in the center engine bay of Challenger before mission STS-41-C on April 6, 1984. Engine 2023-5 was installed in the right engine bay for mission STS-41-G and had flown exclusively on Challenger ever since then. All three engines would remain with Challenger for the rest of her short life.

Jenny Howard, Steely-Eyed Missile Man

This leads us back to Jenny Howard. At 3 PM Central Time, she was on the job, watching her control panel for any sign of problem. Ten minutes later, she gave the go-sign for the systems abort poll, approving the spacecraft for launch. At 4:00 exactly, fifteen hundred kilometers away, Challenger roared off the pad and began burning steadily eastward, building velocity for her orbital insertion eight minutes later.

One of the first two women working in the pressure-cooker boys’ club of Johnson Space Center, Howard was a 1978 graduate of Purdue University, and one of the best there was in a professional environment where nothing less than the best would do. A booster engineer, the difficult part of her launch-day job lasted only ten minutes, but they were ten minutes of incredibly difficult decisions that had to be made at breakneck speeds, and a wrong decision had the potential to kill seven people and destroy an utterly irreplaceable spacecraft.

Three minutes and seventeen seconds after launch, two temperature readings on the central engine went offline, and the third began to climb.

At 4:05:43, the center engine of Challenger, redlined and shut down.

Jenny Howard’s day had just become interesting.

Space Shuttle Challenger, hurtling through space at an altitude of 58 nautical miles (107.1 km) and a downrange of 275 nautical miles (509.3 km), had just lost an engine. Instead of riding a plume of three-quarters of a million pounds of thrust, it was now dragging an unexpected 7,700-pound weight on only half a million.

Howard had decisions to make, and she had a window of mere seconds to make the first: Not whether to abort, but how to do so.

“Mission Control, Houston,” came Fullerton’s voice over the radio, with the smooth, unworried tone of a man on his way to the store to pick up a carton of milk, “we have a center engine down on Challenger.”

275 nautical miles is almost nothing on the scale of Planet Earth, yet Challenger was already too high and too fast to attempt to land in Zaragoza, Spain. The decision rested on Howard and Howard alone. The shuttle could enter a shallow orbit and land in the United States after a single pass around the planet, a dangerous procedure known as Abort Once Around, or AOA. Or she could trust her remaining engines and press on into a lower-than-planned orbit, which would allow NASA to perform damage control and see if further action was needed. Abort To Orbit. Only seconds separated the windows of the two abort modes.

Her data was not making sense to her trained eye. She knew that prior to the creeping redline, the engines had been functioning perfectly. Playing what legendary NASA Flight Director Gene Kranz would later describe as “pure guts poker,” Jenny Howard pushed all her chips in to bet that the sensors were wrong, not the engines. She informed the flight dynamics officer of her decision. The launch would abort to orbit.

“Flight, FIDO. Abort ATO. Abort ATO.”

“Challenger, Houston. Abort ATO.”

Off the recorded audio loop, Howard further instructed the shuttle, “Limits to inhibit,” removing the onboard computer’s ability to shut down engines based on instrument readings. For the next four minutes, responsibility for the lives of every person aboard Challenger lay in her hands. On the fly, she calculated and added an ascent burn to the Aerojet AJ-10 OMS engines, the first such burn in program history, to add thrust to the spacecraft and lighten her fuel load. The left-hand engine’s temperature gauge also crept toward the redline, and the inhibit prevented a second engine shutdown during orbital insertion, saving the orbiter from certain destruction. The right-side engine remained nominal throughout the insertion burn.

At nine minutes and forty-three seconds into the burn, nearly a minute longer than normal, Howard’s remaining two engines finished the last of their fuel and went silent. Challenger was in orbit. Her seven-day mission would accomplish some of the most important science in the thirty-year history of the program.

After the flight, all three engines were examined. There was no damage, not even slight. They had functioned perfectly other than 2020-6’s inexplicable shutdown. As the shuttle underwent examination, it was found that a piece of spray-on insulation had impinged on several analog system wires that controlled the engine temperature readouts, changing their resistance and causing the erroneous readings. The wiring was rewired, and the problem never recurred in the history of the program. Challenger remained to the end of the program the only Space Shuttle to experience an in-flight abort.

Challenger touches down on Rogers Dry Lake after Mission 51-F.

No one who flew aboard Challenger from 29 July to 4 August 1985 would ever go into space again. The explosive finale of Mission 51-L, 73 seconds after launch on 28 January 1986, precipitated a 29-month stand-down of the program, during which many of the astronauts who entered the program in the late 60s and early 70s retired from the agency. Today, engines 2020-6, 2021-6, and 2023-5 lie scattered and broken on the floor of the Atlantic Ocean off the eastern coast of Florida.