Fuel leak on space shuttle Discovery

Again a mechanical problem has delayed the shuttle and cost more millions.

"Space shuttle launch postponed again"

by

Irene Klotz

August 25th, 2009

Reuters

NASA delayed a Wednesday morning liftoff of the space shuttle Discovery because of an apparent problem with a valve in its fuel tank.

It was the second consecutive delay, after stormy weather postponed a launch attempt early on Tuesday. Discovery and its seven-member crew were preparing for a 13-day supply mission to the International Space Station.

The valve problem surfaced as technicians began fueling up the shuttle for a launch set for 1:10 a.m. EDT (0510 GMT) from the Kennedy Space Center in Florida.

"It appears we have a broken fill-and-drain valve," said NASA spokesman Allard Beutel. "It may not be broken, it may be an indicator that was not giving a proper reading."

Managers did not immediately set a new launch date. NASA has until Sunday to get Discovery off the launch pad before the flight would likely be reset for October due to scheduling conflicts with other launches and tests at Cape Canaveral Air Force Station.

In addition, the International Space Station is preparing for its first cargo ship from Japan and cannot receive the shuttle and the new Japanese vehicle simultaneously.

Discovery is scheduled to deliver lab equipment, supplies and spare parts to the station.

Including Discovery's flight, NASA plans seven more shuttle missions to the space station. The 16-nation, $100 billion project is nearing completion after more than a decade of construction 220 miles above Earth.

The shuttles are being retired late next year or early 2011. NASA is working on a new type of spaceship called Orion that can travel beyond the station's orbit to the moon and other destinations.

After the shuttle program ends, the station will depend on Russian, European and Japanese vehicles, though none has nearly the lift capacity of the shuttle, which can haul 50,000 pounds (23,000 kg).

Discovery carries new science racks, a freezer, a sleep station, a second treadmill, food, clothing, supplies and spare parts for the station, including an 1,800-pound (800 kg) ammonia coolant tank that will be installed during two of the spacewalks.

Among the experiments planned for the station is a bone-loss study that uses genetically altered mice as subjects. The mice are flying to the station aboard Discovery and will be left aboard until the next shuttle mission in November.


Good reason to keep feet on the ground

Shuttle Discovery is ready to GO...finally

Shuttle Discovery is ready to GO...finally

At NASA’s Kennedy Space Center in Florida, a technician holds one of Discovery’s gaseous hydrogen flow control valves after its removal. The valves channel gaseous hydrogen from the main engines to the external tank.

Finally, after days of postponement, the Shuttle Discovery is poised for a crucial trip to the ISS. I still question this whole shuttle operation and in the long run mankind's space exploration. The shuttle has been grounded due to some mechanical malfunction involving valves holding the liquid fuel. Suppose this happened in deep space or on the surface of the moon or Mars? Phrases like: "Engineers installed new seals in a fuel vent line, hoping that will solve the problem..." and "Technicians were unable to find the exact cause of the leak." are not satisfactory statements for sound sense of security and problem resolution for manned space flight. I hope all goes good this early evening.

"Repaired space shuttle ready for launch try Sunday"

by

Irene Klotz

March 15th, 2009

Reuters

CAPE CANAVERAL, Florida (Reuters) -- NASA will try again on Sunday to launch space shuttle Discovery on a construction mission to the International Space Station after fixing a fuel leak that triggered a delay last week.

Blastoff is set for 7:43 p.m. (2343 GMT) from Kennedy Space Center in Florida.

Engineers installed new seals in a fuel vent line, hoping that will solve the problem that postponed NASA's first launch attempt on Wednesday when hydrogen gas leaked from the shuttle's fuel tank, posing a fire hazard.

Technicians were unable to find the exact cause of the leak.

"I was a little surprised that we didn't find something more obvious because it was a healthy leak," shuttle launch director Mike Leinbach told reporters on Saturday.

Still, if the shuttle does not leak when it is fueled for flight on Sunday, it will be safe to fly, he added.

NASA plans to start filling the shuttle's tank with 500,000 gallons of liquid oxygen and liquid hydrogen at about 10:30 a.m. (1430 GMT) on Sunday.

NASA has until Tuesday to launch the shuttle or face a delay until April 7 to avoid a schedule conflict with a Russia-led Soyuz mission to replace the station's prime crew.

Discovery will be carrying the fourth and final solar power module for the U.S. part of the station, a $100 billion project of 16 nations. The crew includes Japanese astronaut Koichi Wakata, who will be left behind to serve as a station flight engineer and the first Japanese to live on the outpost.

A troubled shuttle Dicovery?

An aged shuttle may have a problem.

"NASA engineers inspect floating object, protrusion"

by

Juan A. Lozano

This image provided by NASA shows a view of the Space Shuttle Discovery soon after the shuttle and the International Space Station began their post-undocking relative separation on Wednesday June 11, 2008. One of the Expedition 17 crewmembers recorded the photo with a digital still camera. Landing is targeted for Kennedy Space Center at 11:15 a.m. on Saturday.

Associated Press:

NASA engineers were trying to identify an object that floated away from Discovery and were analyzing a protrusion found on its rudder Friday, a day before the space shuttle was scheduled to land. The two issues were noticed after a routine test of the spacecraft's flight control systems and steering jets.

Okay...

"No Problems Seen for Shuttle Landing"

by

John Schwartz

June 14th, 2008

The New York Times

Astronauts aboard the shuttle Discovery prepared for a Saturday landing as their 14-day mission to the International Space Station neared an end.

There was a flurry of activity Friday morning as members of the crew noticed an object floating away from the shuttle into space and saw what appeared to be a small protrusion sticking out of the rudder at the back of the craft. Such objects can be worrisome, since they could indicate a broken part of the shuttle.

But in the past, they have simply turned out to be bits of ice or errant plastic bags floating out of the payload bay. Within a few hours, however, experts on the ground determined that neither issue was a problem. "We're confident that there’s no impact for entry," said Col. Terry W. Virts, Jr., an astronaut serving as the point of contact on the ground for the crew.

Commander Mark E. Kelly of the Navy, the shuttle commander, radioed to the ground shortly after 7:30 a.m. Friday that the object had been spotted floating behind the aft starboard wing. Commander Kelly also pointed out what he called "a bump" seen sticking out from the trailing edge of the port side of the shuttle's rudder, which sits on the craft’s vertical tail fin. The crew transmitted video and still images of the object to the ground.

The object floated away after a series of routine pre-landing procedures in which the crew tested the steering jets, a test which often shakes loose objects off of the spacecraft. The procedures also include working the craft’s flaps. A commentator for the space program's TV service said that the entry flight director, Richard Jones, called in imagery experts and structural and mechanical experts to, as the commentator put it, "hammer this one flat" and make sure there is no concern for landing on Saturday.

If a serious problem had been discovered, the crew could have take the shuttle back to the International Space Station, which it separated from on Wednesday, under what is known as the "safe haven" plan, so that mission managers could determine whether to repair the craft or attempt to send another shuttle as a rescue vehicle.

At 11:30, Colonel Virts radioed to the crew that the issue had been resolved. The object floating away from the craft was one of three clips that attach to the rudder and protects against heating during ascent. It has no function during reentry, and so its loss presents no problem for the craft or crew, he said. As for the protrusion, it is a normal part of the rudder assembly that was exactly the same as it had been during launching, Colonel Virts said, but might have appeared to protrude because the rudder was now being seen at a slightly different angle than before.

Rob Navias, a commentator on the space program's NASA TV service that can be viewed online, said that mission control was now pressing ahead with its previous plans for landing. Discovery is scheduled to land as early as Saturday at 11:15 a.m., though problems like rain, low clouds over the landing strip or high winds could lead mission managers to delay the landing to later on Saturday or put it off to Sunday or even Monday.

The shuttle's mission has been devoted to further construction of the $100 billion space station. Discovery delivered the $1 billion main module of the Japanese laboratory known as Kibo, or Hope. The lab — a cylinder about the size of a tour bus — is the second component of the three-part lab to arrive at the station; a smaller storage module containing equipment for the lab came up on the previous shuttle mission in March. Another section that will expose experiments to space will be delivered on a future mission. Three spacewalks and extensive use of the station's and the shuttle's robotic arms got the new Kibo module out of the shuttle's payload bay and attached to the station. The first part of the module was also moved from its temporary storage position to the top of the main Kibo module.

The crew also carried replacement parts for the station's single toilet, which had been malfunctioning for a week before the shuttle arrived. At a news briefing on Thursday, LeRoy Cain, the head of the mission management team, said that the flight had gone exceptionally well. "It’s been an outstanding mission for us — we have accomplished all of our objectives, and then some."

Discovery is bringing Garrett E. Reisman home from the station, where he has lived since March, and left his replacement, Gregory E. Chamitoff. Mr. Reisman has made no secret of the fact that he is looking forward to seeing his wife, and Friday, mission managers radioed wake-up music selected by Mr. Reisman's wife: a recording of Baby Won’t You Please Come Home by Louis Prima with Keely Smith.

Mr. Reisman thanked the people on the ground for the song, and said "A special good morning to Simone, my favorite earthling." He added, "Get ready, doll face: Discovery's coming home."

In a later interview from orbit with CBS News that was broadcast over NASA TV, Mr. Reisman, who has a reputation as an orbital wit, said, "I'm looking forward to being back home and sleeping in my own bed and using my own toilet." He declared himself "cautiously optimistic" about being able to recover quickly from his time in space, in part because he’s a little over five feet tall and short people tend to recover more quickly than tall people.

"My sensory organs are a little closer to my center of gravity, and my heart has a little less distance to pump to my brain," he said. "I’ve been waiting my whole life, and I think finally this being short is going to come in handy for once."