Wednesday, January 27, 2010

27 January 1967

Apollo 1 Astronauts Roger B. Chaffee, Edward H. White and Virgil I. Grissom in the Apollo simulator (NASA photograph, available here)

43 years ago today, a Friday, was a busy day at the Kennedy Air Force Station’s Launch Complex 34, at what was then called Cape Kennedy, Florida. By 8 a.m. that morning, a cast of almost 1,000 had assembled to support a “plugs-out” launch simulation on AS-204 or “Apollo 204.” Apollo 204 (better known to history as “Apollo 1”) was to be the first manned Apollo space mission, scheduled to fly on 21 February 1967. Shortly after lunch, the flight crew: Virgil I “Gus” Grissom (Lt. Col., USAF), another Air Force light colonel, Edward H. White, and Navy Lt. Commander Roger B. Chaffee, suited up and headed for Pad 34.

 Grissom (at 41 the oldest member of the crew) had already flown in space twice, as well as flying 100 combat missions in the Korean War, garnering an Air Medal with cluster and the Distinguished Flying Cross. Grissom had been told, privately, that he was going to be the first American to walk on the Moon. Colonel White, age 37 (the Senior Pilot) was, during the Gemini 4 mission (3 June 1965), the first American to walk in space. The third crew-member, Lieutenant-Commander Chaffee, age 32 (Pilot) had never flown in space. All were married, with children.

 The other main character in this story, the Apollo capsule, “Spacecraft 012” fully lived up to the old saw about a camel being a horse designed by a committee. The Apollo moonships were then cutting-edge technology, marginally capable of carrying humans into space and back and far more complex than any spacecraft previously flown. Spacecraft 012 was itself a stop-gap design, a “Block I” capsule not meant to fly to the Moon; intended as a sort of proof-of-concept vehicle to test Apollo systems in Earth orbit. Future manned flights were to proceed in the upgraded “Block II” version, but design and construction details of this version were not finalized. Among other things, the prime contractor, North American Aviation, didn’t like the hatch design on the Block I ship: it wanted to install an outward opening hatch on the Block II’s. Spacecraft 012’s hatch recessed inward before opening.

Numerous changes and modifications to Spacecraft 012 caused Apollo 1’s first launch date, in the fall of 1966, to be pushed back to the spring of 1967. In retrospect, this delay was clearly insufficient – the ship was simply not ready. But the timetable was pushing -- NASA was racing both the Russians and President Kennedy’s promise to put a man on the Moon by the end of the decade. Consequently, Spacecraft 012 was accepted from the contractors and mated to its Saturn 1B booster on Pad 34 despite a number of known and unknown defects and faults – and with its documentation file in appalling disorder. Many problems were attended to. . .but some were not.

The crew was dubious about the readiness and even the safety of their ship: Colonel Grissom telling his wife that Spacecraft 012 was a lemon. Contractors and engineers on the ground had concerns also, but there was a critical blind spot in most of this thinking, which was primarily centered around problems the Apollo might eventually encounter in space, not on the ground. . .

Flight training and testing proceeded, and on the 27th of January, NASA went ahead with the “Plugs Out” test, in which the spacecraft (on the pad atop its unfueled booster) would be manned, sealed-off from the outside; operating totally on its internal power and systems. A simulated countdown would be conducted, and the crew would practice operation of the spacecraft through several hours of post-liftoff flight, the cabin pressurized with pure oxygen. Shortly after 1 p.m., the astronauts, wearing their full, bulky space suits, entered the space capsule, and technical problems immediately began. Grissom plugged his suit into the spacecraft oxygen system, and complained of a foul, buttermilk-like taste. Proceedings halted while the technicians tried to isolate the problem, apparently without success.

The test resumed. At 2:42 p.m. the white-room technicians closed and sealed the spacecraft hatch, then locked the booster cover cap in place. None then knew that the sealing of the hatch marked the closing of another door, for three of the finest men America ever produced had entered their pyre and tomb, and would not leave the spacecraft alive.

Once the hatch was closed, sea-level air was removed from the space suits and the cabin, and replaced with pure oxygen, at a pressure of 16.7 pounds per square inch. Unlike the earlier Mercury and Gemini capsules, Apollo, built for longer voyages, was designed, once in orbit, to allow for a more or less shirt-sleeve environment. Of course, this meant a pressurized cabin with an artificial atmosphere. The engineers at North American suggested an Earth-like oxygen-nitrogen atmosphere. However, NASA worried about decompression sickness and nitrogen mixture issues, and selected pure oxygen. Pure oxygen under (as here) high pressure – burns very well.

The test rolled on, and problems continued as afternoon dragged into evening. There was a problem controlling oxygen flow that repeatedly triggered a master alarm. The control center technicians believed the fault was caused by excessive crew movement, but the problem was not actually resolved. Meanwhile, the crew had difficulty communicating with the controllers in the blockhouse and in two other buildings because of persistent static interference, and an open microphone someplace in the spacecraft that the crew was unable to locate. An exasperated, and, by now, exhausted Grissom wondered aloud: “How are we going to get to the Moon if we can’t talk between three buildings?” The ground controllers became increasingly annoyed and preoccupied by the communications problem.

About 6:30 p.m., the crew members, strapped in their crew couches, were going through a checklist when control center instruments recorded both a surge in oxygen flow into the spacesuits and electrical spikes. At about this same time one of the astronauts said: “Fire. I smell fire.” This changed literally in a flash – two seconds later, horrified ground controllers saw flames appear on their cameras and Astronaut White shouted insistently that there was a “fire in the cockpit!”

An escape drill was specified in the manuals, which the astronauts were supposed to be able to complete in 90 seconds. In practice, the hatch arrangement made this impracticable, even if it would have been possible to unseat the hatch and open it inward against the pressure of the oxygen in the spacecraft. The astronauts were apparently able to accomplish part of the drill: the lights were turned up, and Astronaut White, seated in the middle, had begun work on the ratchet behind his head that controlled the hatch. But the astronauts didn’t even have 90 seconds before they were overcome by smoke.

Technicians frantically rushing to the capsule area to assist were driven back by flames so hot that they had ruptured the hull of capsule. Grissom, White and Chaffee never had a chance to escape, caught behind a double-hatch that took over five minutes to open, bathed in highly flammable pure oxygen, strapped to their crew couches in bulky space-suits. The trapped astronauts died by inhalation of toxic gases and burns.

The electrical fire which asphyxiated the crew was a blow not only to the families of the crew, and to all who knew these men, but to the whole nation, already reeling from Vietnam. An investigation revealed faulty wiring and substandard plumbing throughout the spacecraft (which was full of flammable materials), with the most likely cause of the fire being a short produced by the interaction of a wire with the insulation rubbed off and the spacecraft’s environmental control unit. Changes in the Apollo spacecraft included a different artificial atmosphere, a different hatch and different materials, all of which made Apollo relatively safer. Still, as Apollo 13 later reminded us, the amazing moonships were incredibly dangerous. It is almost impossible to imagine our much more risk-adverse society building such ships now.

Grissom and Chaffee were buried in Arlington National Cemetery, White at West Point. Apollo 1’s booster was later used to fly the first Lunar Module (Apollo 5) in an unmanned Earth orbital test. The fate of the capsule itself was very strange: once the investigators were through with it, Spacecraft 012 was sealed up and placed in a warehouse in Langley, Virginia, where (after a move to a new facility in 2007) it rests today.

Just 21 months after the fire, Pad 34 launched the first successful manned Apollo mission, Apollo 7 -- flown by Apollo 1’s back-up crew. Launch Complex 34 was then taken out of service and dismantled. The concrete launch platform, the base of the pad, still exists, and bears two plaques, the inscription on one of which is an appropriate way to close this essay:
In memory of those who made the ultimate sacrifice so others could reach for the stars; Ad astra per aspera (a rough road leads to the stars); God speed to the crew of Apollo 1.

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