Flight Safety – June 2006

by Dr. Richard Stimson

in Others

Two significant events concerning space flight and commercial aviation occurred in June 2006.

The first concerns the Space Shuttle. The next flight of the shuttle is scheduled for July 1. Two NASA engineers voiced their concern that the shuttle isn’t ready to fly.

Bryan O’Connor, NASA’s lead safety official, and Christopher Scolese, its chief engineer voted “no go” when agency officials met recently at the Kennedy Space Center in Florida. In an unusual move the rest of the officials voted yes for an ontime launch including NASA Administrator Michael Griffin.

The concern of the two officials, who voted against the launch, was that the insulating foam that covers 34 metal brackets on the shuttle’s external fuel tank might dislodge during launching and damage the spacecraft’s protective heat shield beyond repair.

The July 1 launch was approved despite the objections because in the event of a damaged heat shield, the astronauts could stay in the International Space station until rescued by another shuttle.

The loss of the shuttle Columbia and its crew on Feb. 1, 2003 was caused by foam debris. NASA engineers have redesigned the fuel tank and removed most sources of large pieces of potentially damaging debris.

However, during the shuttle Discovery launch last July, a hazardous amount of foam fell from its tank. As a result NASA engineers have further reduced the amount of foam used.

O’Connor and Scolese believe that the foam issue is still not fully resolved. They note that their concern is with the fate of the shuttle and not the safety of the seven-man crew of Discovery who can remain in the International Space Station in an emergency.

Update: Charlie Camarda, a member of the astronaut corps and long time NASA engineer, was removed from his job for his safety views. He wrote an e-mail to his engineering team saying that he was most proud of all of them at the flight readiness review meetings “when you stood up and presented your dissenting opinions and your exceptions/constraints for flight.”

Camarda told colleagues that he was forced out as director of engineering at Johnson Space Center after praising colleagues who dissented about going forward with the next flight of Discovery. He said he refused to step down from the high-level mission management team and “asked that if I would not be allowed to work this mission that I would have to be fired from my position and I was.”

For his work at NASA, Camarda received seven patents and more than 21 NASA awards for his technical innovations and accomplishments.

Update: (July 6) NASA engineers and managers are optimistic that the shuttle has reached orbit with no damage and substantially less shedding of foam debris from the external tank than in previous flights. There will be additional examinations over the next few days.

The second event concerns commercial airplanes landing in wet or icy weather.

On Dec. 8 last year, a Southwest Airlines jet (Flight 1248) skidded off the runway on to a highway while landing at Midway Airport, Chicago and crushed a car, killing a 6-year-old boy.

At a two-day FAA hearing last week new regulations were announced that would require pilots to add a buffer of at least 15% to their stopping-distance estimates on wet or icy runways.

The new rules, according to FAA airplane performance engineer Don Stimson (my son), mandate that when conflicting or mixed assessments of runway conditions are issued, pilots must use the worse case scenario, effectively erring on the conservative side.

The pilots of Flight 1248 had calculated much shorter stopping distances for their landing at Midway, 5,778 feet under poor runway conditions to 5,253 feet under fair conditions. Midway’s longest runway is 6,522 feet long, but obstructions outside the airfield prohibit landing on the first 696 feet.

Under the new rules, a stopping distance of 8,535 feet must be available for a plane comparable in weight and landing speed to the Southwest 737-700 involved in the Dec. 8 accident based on conditions of the runway that day.

Pilots and safety board investigators rated the first half of the Midway runway as fair and the second half poor just before the accident.

The final report and safety recommendations are expected to be released in early 2007.

References:

New York Times, “In Opposing Launching, 2 NASA Officials Feared Shuttle’s Loss, Not Crew Safety,” June 22, 2006.

Chicago Tribune, “Midway gets U.S. warning on snow; More runway needed in wet or icy weather,” June 22, 2006.

Richmond Times-Dispatch, ” NASA Official says his safety views cost job,” June 28, 2006.

Previous post:

Next post: