Wednesday, November 24, 2010

NASA Delays Discovery Launch to Complete Crack Tests

Crack location on the inner section of the tank. (NASA)

NASA has pushed back the target launch date of space shuttle Discovery by two weeks due to the need for more tests on the cracked section of her external fuel tank.

Four cracks were discovered on the inter tank region where the top section of the rocket boosters attach following a launch scrub on November 5.

Once the launch team drained the super cold fuels from the two tanks located inside the external tank, one crack was found followed by three more over the next day.

The inner tank region has a total of eight panels around the diameter, including and two 2-inch thick aluminum panels at the section where the forward SRB's attach.

Cracks located on two 21-foot long aluminum brackets known as stringers are being repaired.

NASA wants to learn if there are more stress cracks around the diameter of the tank.

Discovery's rust colored fuel tank is loaded with 535,000 gallons of super cold liquid hydrogen and liquid oxygen on launch day. The fuels mix to power the orbiter's three main engines during the first eight minutes of launch.

Launch is now targeted for no earlier than December 17 at 8:51 pm EST, however due to the need for extensive tests over the coming week, a more firm launch time could move the space mission to early January or February.

NASA states that Dec. 17 is a target only date and the team is not pressured by delays now or in the future.

Technicians at the Kennedy Space Center will take Thanksgiving and Friday off before picking up testing again on Saturday. X-ray tests of several regions of the ribbed portion of the tank will be performed.

Technicians "using two forms of imagers are examining the stringers that make up the ribbed intertank section", NASA's Steven Siceloff stated recently at Kennedy.

"There are 108 of the 21-foot-long metal stringers that connect the cone-shaped liquid oxygen tank on top with the oblong liquid hydrogen tank on the bottom," Siceloff added.

The technicians need to use scanners to visually see down through the insulation covering the aluminum structure of the tank for further evidence of more cracks.

Siceloff went on to say that "the scans are reviewed by officials at NASA's Marshall Space Flight Center in Alabama where the tank was designed, and at NASA's Michoud Assembly Facility outside New Orleans where the tank was built."

The next mission management team meeting is planned for December 3 in the hopes of learning where the space agency is in making necessary repairs and learning from the tests performed.

NASA managers state that there are several unknowns related to the tank's stress cracks.

Friday, November 05, 2010

Delta II Lifts-off with Italian Surveillance Satellite

Long range IR Camera captures Delta's booster separation. (VAFB)

After several delays this week, a Delta rocket lifted-off tonight from southern California on a satellite deployment mission for Italy.

The United Launch Alliance Delta II 7420-10 launched from Vandenberg, AFB at 10:20:03 pm EDT, with the Italian COSMO SkyMed 4 surveillance satellite.

Vandenberg is a Pacific coast military air base located three hours northwest of Los Angeles.

"This was a critical launch for completing the COSMO-SkyMed constellation and Team Vandenberg performed brilliantly," Col. Richard Boltz, commander of 30th Space Wing, stated moments after the spacecraft was safely in orbit.

This evening's launch marked the 350th Delta flight, and just the third Delta II launch of the year.

The launch control room was draped in several Italian flags as the white rocket soared out over the Pacific Ocean.

One minute into flight, the Delta II four strap on solid fuel boosters burned out having done their job through the dense atmosphere region. Twenty-five seconds later, the boosters were then separated as the core main engine continued to push the rocket upward.

The 126-foot tall white rocket uses a Pratt & Whitney Rocketdyne RS-27A core engine and the four boosters to provide a combined thrust at launch at just over 700,000 pounds.

Four minutes into the ascent, the rocket was passing through fifty miles in altitude, and was located 130 miles south of the air base.

Following several burns to place the Delta's upper stage in a proper orbit and location, the satellite separated at 11:18 pm as the craft passed over Africa's central east coast.

"COSMO-SkyMed is a constellation composed of four satellites equipped with Synthetic Aperture Radar (SAR) operating at X-band," the satellite's Italian operator states. The COSMO-Skymed 4 will operate for Mediterranean basin observation for six or more years.

GLH2 Leak and Foam Crack Delays Shuttle Launch

Sunrise at the Kennedy Space Center today. (NASA)

A cracked piece of foam insulation and a leaking fuel region -- both on the external tank of the space shuttle Discovery -- has forced a three week delay in the start of her final flight.

Today's launch attempt began with the on time start of the fueling of the ship's rust colored external fuel tank at 6AM EDT.

However, nearly two hours into fueling, the launch team discovered a small gaseous hydrogen leak at the Ground Umbilical Carrier Plate (GUCP) on the back side of the large tank.

The GUCP carries the gaseous hydrogen away from the space shuttle to a huge fire burning stand a hundred yards away where it is burned off.

Similar GLH2 leaks occurred twice last year and required several days to remove the plate located on the opposite side of where the shuttle is attached and repair the seal.

Launch pad workers will also investigate "a crack in the external tank foam that developed as super cold liquid hydrogen and liquid oxygen were being drained from the tank," a NASA spokesperson stated today. "The crack did not develop until after the launch attempt was called off."

Work to repair the huge U-shaped foam crack (above image) will be discussed over the next few days.

Following the discovery of the crack during detanking this morning, NASA's Mission Management team elected to delay launch until no earlier than November 30.

NASA had until Sunday and maybe Monday as the last days to launch the spacecraft or face a launch delay until November 30 due to sun angels at Discovery's planned port-of-call -- the International Space Station.

The Sun angels issue, known as beta cutout, will warm the station too much with a shuttle docked due to the orientation the pair would fly. Once docked, the space station turns itself with the help of the orbiter's thrusters so that Discovery's belly is in the direction of travel.

This helps minimize micrometeorites from striking the orbiter's payload bay, glass windows and engine nozzels.

On Monday, NASA hopes to be able to discuss what direction the launch team will move towards as the month decreases in time.

Small LH2 Leak Discovered during Discovery Fueling

The space shuttle Discovery is in the final hours of her launch countdown this morning as NASA prepares to begin the oft-delayed 11 day mission.

NASA's launch team began filling Discovery's fuel tank with 535,000 gallons of super cold liquid hydrogen and liquid oxygen this morning at 6:09 am EDT, after first chilling down the fuel lines which feed the fuel to the rust colored tank.


As the Sun began to shed light on the darkness of the Kennedy Space Center and the liquid hydrogen begin filling up the shuttle's external tank, the launch team detected a small leak at the location where it enters the tank.


Known as the Ground Umbilical Carrier Plate on the backside of the fuel tank, a small leak is now giving the launch team concern as they continue their countdown toward launch this afternoon at 3:04:01 pm.

Stay tune for updates via Twitter: @SpaceLaunchNews.

Thursday, November 04, 2010

Rain Showers push Discovery's Launch to Friday

Discovery waits out rain showers this morning. (NASA)

The much delayed launch of the space shuttle Discovery will have to wait again until Friday as rain showers are forecast to fall through launch time here on America's Space Coast.

NASA Mission Managers met this morning at 5:30 am EDT to access the weather. Rain and a low cloud ceiling will cover the Kennedy Space Center through the entire day today. It is forecast to clear over night tonight bringing cooler, drier weather for Friday.

Launch of Discovery on her 39th and final voyage upon the ocean of space is set now for Friday afternoon at 3:04:00 pm -- the launch window is five minutes.

Technical issues with fuel and gas leaks in the orbiter's right OMS pod and a bad fuse for a main engine back up controller has delayed lift-off from Nov. 1.

Last evening, mission managers elected to proceed with a launch attempt for today knowing that their meeting to access the weather would ultimately scrub launch for 24 hours.

At 8PM on Thursday, space center technicians began the thirty minute job to rollback the protective service structure from around the space craft and into the launch position.

Air Force meteorologist Kathy Winters is currently giving an 60% favorable forecast leading toward launch time tomorrow.

A cloud ceiling and upper level winds could be of concern within 30 miles of the launch pad.
Head winds in the event of an RTLS (Return to Launch Site Abort) will also be looked at tomorrow.

Saturday's forecast shows higher winds being more of a concern, with Sunday looking better weather wise.

NASA needs to launch the 26 year-old spacecraft before November 7 or risk keeping her on earth until the opening days of December. This is due to sun angles on the station through out November which can cause instruments to over heat.

Once launched, Discovery's all veteran crew of commander Steven Lindsey, pilot Eric Boe and mission specialists Timothy Kopra, Michael Barratt, Nicole Stott and Alvin Drew will spend two days performing rendezvous maneuvers to catch up with and dock with the International Space Station.

Two days after her launch, Discovery will arrive at the Space Station to begin eight days of docked operations to resupply with food, fuel and hardware; and add the final U.S. segment to the growing city in space.

Discovery will deliver the final American segment known as the Permanent Multipurpose Module, a bus sized cylindrical segment which will be used for storage. It will help free up more space inside the station's working and living segments for the crew of six.


Formally known as the Leonardo logistics module, the PMM has actually flown to station several times most recently two flights ago.

Inside the PMM will be 6500 pounds of cargo, spare parts, R2 - a robo-naut which will be used outside the outpost; and personal crew supplies to help resupply earth's orbiting outpost in space. Discovery's middeck will carry another 1500 pounds of supplies, too.

Robonaut will remain in the PMM through Discovery's flight, and will later be moved so that it's two halves can be mated together and placed outside the station in the weeks to come.

Kopra and Drew will also perform two spacewalks during this 35th shuttle flight to earth's orbital outpost, on flight days 5 and 7.

This will mark Discovery's final space flight. NASA only has only two more space shuttle flights left after Discovery, with Endeavour flying her final scheduled flight on February 27, and Atlantis by next autumn.

Tuesday, November 02, 2010

Discovery's Launch Delayed until Thursday

The launch of space shuttle Discovery's final flight was delayed another day so that engineers could troubleshoot a faulty backup controller on one of her three main engines.

NASA announced the countdown delay at 5:30 pm EDT today, after a backup computer which controls the activity of engine 3 did not come online during routine power checks.

This reporter announced the delay thirty minutes earlier via Twitter (@SpaceLaunchNews).

Mission Management's chairman Mike Moses stated late on Tuesday that the "main engine controller gave us a funny signature" when the launch team tested the computers.

Engines 1, 2 and 3 each have a primary and secondary computer which controls the engines thrust levels and movement during the ascent.

When the launch team went through the power checks, the backup controller on engine three "did not come on," Moses stated. Engineers then power cycled the circuit breaker on Discovery's flight deck for the computer several times to try to get it to come online.

Ninety minutes "later the controller came on, and it started working. It healed its self in time," Moses added.

Overnight tonight and into Thursday midday, the launch team will continue to trouble shoot why the engine controller's electrical signature gave them a hiccup.

NASA also added that the one day delay gives the launch team a much needed rest, having been on console since Sunday afternoon.

The MMT will meet again on Wednesday at 2PM to determine whether or not to pick up the countdown and go fly on Thursday.

If launch is confirmed for Thursday, the launch team will resume the countdown at the T minus 11 hour mark at 5:30 pm on Wednesday.

Lift-off of Discovery's 39th and final space flight will begin at 3:29:43 pm, as the twin solid rocket boosters ignite.

The weather outlook for Thursday is iffy with Air Force meteorologist Kathy Winters giving an 80% unfavorable forecast leading toward launch time. Clouds and moisture within 30 miles of the launch pad will be of concern mid afternoon.

Delta II Launch to Try Again Tonight

A Delta rocket in California suffered a last minute scrub on Monday evening and technicians hope to have the vehicle ready for another try tonight.

As the countdown neared two minutes, a cutoff was ordered when engineers saw "an insufficient flow of gaseous nitrogen (GN2) in the Delta II engine compartment," United Launch Alliance stated moments after the scrub.

The GN2 flow is used to keep areas near the super cold fuel lines warm at launch.

Do to this flight's one-second launch window, the scrub occurred immediately and the launch team went into a 24-hour turn around.

The ULA Delta II 7420-10 with the COSMO-Skymed 4 satellite is set for a third launch attempt tonight at 10:20 pm EDT (7:20 pm Pacific) from complex 2 at Vandenberg, AFB in California.

This evening's launch will mark the 350th Delta flight; and just the third Delta II launch of the year.

The 126-foot tall white rocket will lift-off with a Pratt & Whitney Rocketdyne RS-27A core engine and four strap on solid boosters to provide the initial thrust for it's climb to orbit. The combined thrust at launch is just over 700,000 pounds.

The launch path will carry the vehicle almost due south out over the Pacific Ocean to align it for an intended Polar orbit.

Spacecraft separation over Africa's east coast should occur at 11:18 pm EDT.

"COSMO-SkyMed is a constellation composed of four satellites equipped with Synthetic Aperture Radar (SAR) operating at X-band," the satellite's Italian operator states. The COSMO-Skymed 4 will operate for Mediterranean basin observation.

Tonight's launch will place the fourth environmental monitoring and surveillance spacecraft in a specialized orbit for use by both military and civilian use.

The new earth imaging satellite's six year mission "is financed by the Ministry for Education, Universities and Scientific Research, the Italian Space Agency (ASI) and the Ministry of Defense", according to Telespazio which is the control center for the satellite constellation.

Meanwhile, on the south side of Vandenberg, a brush fire has been burning since Thursday on the dry fields of the military base. Over 500 acres have been burned since a suspect power line caused the fire days ago in the Bear Creek region.

Although this fire will not effect the Delta's flight, Vandenberg officials told me that "the area involved is known to contain unexploded ordnance".
 
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