NASA - National Aeronautics and Space Administration

Disaster at Complex 34

While facilities on Merritt Island were being prepared for the Apollo-Saturn V, testing continued on Cape Canaveral with the smaller Saturn I and IB vehicles, verifying the equipment and systems to be used on later Moon flights. The 13th Saturn flight--the third Saturn 1B--on Aug. 25, 1966, proved to be the 13th success. It fulfilled all mission objectives. The team at KSC then began to prepare for the first manned Apollo mission at Launch Complex 34, scheduled for sometime late in 1966. The tragedy of Apollo-Saturn 204, later renamed Apollo 1, and its three-man crew would become etched in the annals of space flight.

NASA selected two veterans and one rookie as the crew for the first manned Apollo mission. Command Module Pilot Virgil Grissom had skippered Mercury's Liberty Bell 7, America's second suborbital manned flight, in July 1961, and Gemini's Molly Brown, the first manned Gemini, in March 1965. Edward White, while on the fourth Gemini flight, had become the first American to walk in space. With these two experienced space travelers would be the youngest American ever chosen to go into space, 31-year-old Roger Chaffee. The purpose of their flight was to check out launch operations, ground tracking and control facilities, and the performance of the command and service modules in orbit.

Following all the usual preliminary testing, the crew prepared for the simulated countdown test, the last major test scheduled prior to launch. There would be no fuel in the Saturn IB, designated Apollo-Saturn 204. Grissom, White, and Chaffee would don their full space suits and enter the Apollo, breathing pure oxygen to approximate orbital conditions as closely as possible. Apollo Mission Control at the Manned Spacecraft Center in Houston would pick up the action after simulated liftoff and would monitor the performance of the astronauts.

The astronauts entered the Apollo at Launch Complex 34 at 1 p.m., Friday, Jan. 27, 1967. Problems immediately arose. Grissom reported a strange odor in the suit loop which he described as a "sour smell somewhat like buttermilk." After taking a sample of the suit loop, the crew decided to continue the test. The next problem was a high oxygen flow indication which periodically triggered the master alarm. The high flow was believed to be the result of movements made by the crew. A third serious problem arose in communications, first between the control room and Grissom and then later extending between the blockhouse at Complex 34 and other spacecraft monitoring facilities. The communications problem forced a hold of the countdown at 5:40 p.m. By 6:31 p.m., the test conductors were preparing to resume the count when ground instruments showed an unexplained rise in the oxygen flow into the space suits of the crew. One of the crew, presumably Grissom, moved slightly.

Four seconds later, an astronaut, probably Chaffee, announced almost casually over the intercom, "Fire, I smell fire." Two seconds later, astronaut White's voice was more insistent, "Fire in the cockpit!"

Inside the blockhouse, engineers and technicians looked up from their consoles to the television monitors trained at the spacecraft. To their horror, they saw flames licking furiously inside the smoke-filled Apollo. Men who had gone through Mercury and Gemini tests and launches without a major incident stood momentarily stunned.

Outside the white room that gave access to the spacecraft, emergency procedures to rescue the astronauts were ordered. Technicians started toward the spacecraft. Then the command module ruptured. Flames and thick black smoke billowed out, filling the room. A new danger arose. The fire and heat might set off the launch escape rocket atop Apollo. This, in turn, could ignite the entire service structure. Instinct told the technicians to get out while they could. Many did, but six remained and continued rescue attempts. Despite the intense heat, thick smoke and the danger overhead from the escape rocket, they managed to get Apollo's hatch open. But it was too late. The astronauts were dead. A medical board determined later that the crew died of carbon monoxide asphyxia, with thermal burns as a contributing cause.

The sudden and unexpected deaths of the three astronauts caused international grief and widespread questioning of the space effort. Momentarily, the whole manned lunar program stood in suspense.

On Feb. 3, NASA Administrator James Webb set up a review board to perform a thorough investigation. That same day, ground crews at KSC began to sift through the burned hulk of Apollo 204. At the Manned Spacecraft Center in Houston, engineers duplicated conditions of Apollo 204 (without crewmen in the capsule), reconstructing events as studies at KSC brought them to light.

The investigation at Pad 34 showed that the fire started in or near one of the wire bundles to the left and just in front of Grissom's seat on the left side of the cabin--a spot visible to Chaffee. The fire probably was invisible for about five or six seconds, until Chaffee sounded the alarm. From then on, the test fire duplicated by the Manned Spacecraft Center engineers followed, almost to a second, the pattern of intensity of the oxygen fire aboard Apollo 204.

On April 5, the review board submitted its formal report to the administrator. It summarized its findings as to the cause of the fire in this sequence: "The fire in Apollo's floor was most probably brought about by some minor malfunction or failure of equipment or wire insulation. This failure, which most likely will never be positively identified, initiated a sequence of events that culminated in the conflagration."

Dr. Debus, KSC's director, summed up the feelings of the launch team in a statement before a congressional hearing. Speaking candidly, he said: "As director of the installation, I share the responsibility for this tragic accident and I have given it much thought. It is for me very difficult to find out why we did not think deeply enough or were not inventive enough to identify this as a very hazardous test.

"We never knew that the conflagration would go that fast through the spacecraft so that no rescue would essentially help. This was not known. This is the essential cause of the tragedy. Had we known, we would have prepared with as adequate support as humanly possible for egress."

NASA moved quickly to better assure that a like tragedy would not occur in the future. A new flameproof material called Beta Cloth was substituted for nylon in the space suits. Within the spacecraft itself, technicians covered exposed wires and plumbing to preclude inadvertent contact. They redesigned wire bundles and harness routings. The cabin atmosphere was changed from 100 percent oxygen to 60 percent oxygen and 40 percent nitrogen.

At Complex 34 itself, technicians put a fan in the white room for ventilation. They added water hoses, fire extinguishers and an escape slidewire. Astronauts and crew workers could ride down this wire during emergencies, reaching the ground in seconds.

Top priority was given to redesigning the hatch. The new Apollo hatch would be a single hinged door that swung outward with only one-half pound (0.23 kilograms) of force. An astronaut could unlatch the door in three seconds. The hatch would have a push-pull unlatching handle, a window for visibility in flight, a plunger handle inside the command module to unlatch a segment of the protective cover, a pull loop that permitted a pad man to unlatch the protective cover from the outside, and a counterbalance to hold the door open.

Then, after the most careful consideration, a difficult decision was made: After installation of new equipment and modifications of procedures, the Apollo program, with its objective of landing on the lunar surface by the end of the decade, would continue.