Spaceflight Now





The Mission




Orbiter: Endeavour
Mission: STS-127
Payload: ISS 2J/A
Launch: July 15, 2009
Time: 6:03 p.m. EDT
Site: Pad 39A, Kennedy Space Center, Florida
Landing: July 31 @ approx. 10:48 a.m.
Site: Shuttle Landing Facility, KSC
Mission Status Center

STS-127 Video Coverage

High Definition Video

NASA TV (rev. Q)

Launch Windows Chart

Countdown Timeline

Ascent Timeline

Master Flight Plan

STS-127 Mission Index

Our Shuttle Archive




The Crew




Meet the astronauts flying aboard Endeavour's STS-127 mission.

CDR: Mark Polansky

PLT: Doug Hurley

MS 1: Chris Cassidy

MS 2: Julie Payette

MS 3: Tom Marshburn

MS 4: Dave Wolf

Up: Tim Kopra

Down: Koichi Wakata

Current Demographics




Spaceflight Now +



Subscribe to Spaceflight Now Plus for access to our extensive video collections!
How do I sign up?
Video archive

STS-127: The programs

In advance of shuttle Endeavour's STS-127 mission to the station, managers from both programs discuss the flight.

 Play

STS-127: The mission

A detailed step-by-step preview of Endeavour's STS-125 mission to install an external exposure platform on the station's Kibo science facility.

 Play

STS-127: The EVAs

The lead spacewalk officer provides indepth explanations of the EVAs on Endeavour's assembly mission to the station.

 Play

STS-127: The crew

The seven astronauts launching on Endeavour meet the press in the traditional pre-flight news conference.

 Play

Become a subscriber
More video



Special space shuttle fueling test expected next week
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: June 23, 2009


Bookmark and Share

Shuttle managers plan to meet Wednesday to review procedures for a fueling test next week to assess the performance of an alternative internal seal and shim-like washers intended to eliminate a leak in a gaseous hydrogen vent line that has twice grounded the shuttle Endeavour.


Credit: NASA
 
If the fueling test goes well and sensors don't detect hydrogen concentrations greater than the allowable 40,000 parts per million, NASA will press ahead for a third attempt to launch Endeavour on a space station assembly mission at 7:39 p.m. July 11.

If higher-than-allowable leakage is again detected, program managers could be forced to move Endeavour to a different tank and boosters, triggering more significant downstream delays.

Engineers believe they understand the problem - a slightly misaligned vent port housing built into the side of Endeavour's external tank - but it remains to be seen whether the proposed fix will, in fact, eliminate the leaks that have grounded Endeavour.

The 7-inch-wide hydrogen vent line in question is needed to carry away potentially dangerous hydrogen vapor that builds up in the tank as it is loaded with fuel. By cycling a valve in the vent line, the proper internal pressure is maintained and excess hydrogen gas is routed to a "flare stack" near the pad where it is harmlessly burned away.

The launch pad vent line is attached to the side of the tank with a ground umbilical carrier plate and a quick-disconnect fitting. At liftoff, an explosive bolt is detonated and the vent line drops away from the tank.

Endeavour was grounded June 13 and 17 when sensors detected hydrogen concentrations greater than 40,000 parts per million at the umbilical plate interface.

Engineers initially believed the problem involved a slight misalignment of the vent line umbilical plate and/or trouble with a Teflon seal in the quick-disconnect fitting. A similar problem grounded the shuttle Discovery for four days last March.

The seal was replaced, but the system leaked again during fueling for the June 17 launch try. After additional analysis, engineers concluded the rectangular vent port housing itself, which was riveted into the side of the tank about six-tenths of a degree out of vertical, was preventing the umbilical plate/quick-disconnect fitting from maintaining a tight seal under cryogenic conditions.

The proposed fix is to install a two-piece flexible seal in the quick-disconnect fitting in place of the more rigid single-piece Teflon seal used earlier. In addition, the umbilical plate that connects the vent line to the tank will be mounted using different shim-like washers to help counteract the effects of the vent port misalignment.

In so doing, engineers hope to maintain a tight fit at the vent line interface despite the temperature-induced shrinkage and flexing that occurs when the tank is filled with propellants. The leak only shows up when the equipment is exposed to cryogenic conditions.

To save time and minimize the chance of introducing any variables that might affect the test, Program Manager John Shannon told the engineering team to forego adding any additional instrumentation for the upcoming fueling test. Instead, Endeavour's tank will be in normal flight configuration when it is loaded with a half-million gallons of liquid oxygen and hydrogen rocket fuel.

Two fueling test timelines are under consideration but managers favor a plan that calls for installing the new seal late this week and re-rigging the umbilical plate attachments Saturday. The fueling test itself would be expected between 7 a.m. and 10 a.m. on either June 30 or July 1.

Spaceflight Now Plus
Additional coverage for subscribers:
VIDEO: POST-SCRUB NEWS BRIEFING PLAY
VIDEO: FIRING ROOM UPDATE WITH LAUNCH DIRECTOR PLAY
VIDEO: SCRUB NO. 2 DECLARED DUE TO HYDROGEN LEAK PLAY

VIDEO: SUNDAY'S UPDATE FROM MISSION MANAGEMENT TEAM PLAY
VIDEO: LEAK POSTPONES SHUTTLE ENDEAVOUR LAUNCH PLAY

VIDEO: TIME-LAPSE OF SUN SETTING OVER PAD 39A PLAY
VIDEO: ANOTHER TIME-LAPSE OF GANTRY RETRACTION PLAY
VIDEO: TIME-LAPSE OF LAUNCH PAD TOWER ROLLBACK PLAY

VIDEO: PRE-LAUNCH INTERVIEW WITH MARK POLANSKY PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH DOUG HURLEY PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH CHRIS CASSIDY PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH JULIE PAYETTE PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH TOM MARSHBURN PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH DAVE WOLF PLAY

VIDEO: THE STS-127 MISSION PREVIEW MOVIE PLAY
VIDEO: THURSDAY'S PRE-LAUNCH NEWS CONFERENCE PLAY
VIDEO: JAPANESE SCIENCE FACILITIES ABOARD STATION PLAY
VIDEO: COUNTDOWN BEGINS TICKING FOR SATURDAY'S LAUNCH PLAY
VIDEO: LAUNCH COUNTDOWN PREVIEW BRIEFING PLAY
VIDEO: CREW ARRIVES JUST BEFORE MIDNIGHT PLAY | HI-DEF
VIDEO: GET TO KNOW ENDEAVOUR'S ASTRONAUTS PLAY

VIDEO: ASTRONAUTS PRACTICE EVACUATION OF SHUTTLE PLAY | HI-DEF
VIDEO: CREW BOARDS SHUTTLE FOR PRACTICE COUNT PLAY | HI-DEF
VIDEO: ASTRONAUTS SUIT UP FOR DRESS REHEARSAL PLAY | HI-DEF
VIDEO: CREW INSPECTS CARGO IN THE PAYLOAD BAY PLAY | HI-DEF
VIDEO: TRAINING SESSIONS AT LAUNCH PAD AND BUNKER PLAY | HI-DEF
VIDEO: INFORMAL CREW NEWS CONFERENCE AT LAUNCH PAD PLAY
VIDEO: ASTRONAUTS ARRIVE FOR PRACTICE COUNTDOWN PLAY

VIDEO: FLIGHT READINESS REVIEW SETS LAUNCH DATE PLAY

VIDEO: PAD 39A GANTRY ENCLOSES SHUTTLE PLAY | HI-DEF
VIDEO: ROLLAROUND MOVES ENDEAVOUR TO PAD 39A PLAY | HI-DEF
VIDEO: ENDEAVOUR IS HAULED OFF LAUNCH PAD 39B PLAY | HI-DEF
VIDEO: TIME-LAPSE OF SHUTTLE'S LAUNCH PAD SWITCH PLAY

VIDEO: SHUTTLE AND STATION PROGRAM UPDATE PLAY
VIDEO: THE STS-127 MISSION OVERVIEW BRIEFING PLAY
VIDEO: PREVIEW BRIEFING ON MISSION'S SPACEWALKS PLAY
VIDEO: THE ASTRONAUTS' PRE-FLIGHT NEWS BRIEFING PLAY

VIDEO: PAD 39B AND ITS LAST SPACE SHUTTLE PLAY | HI-DEF
VIDEO: ENDEAVOUR'S SUNRISE ARRIVAL AT PAD 39B PLAY | HI-DEF
VIDEO: MIDNIGHT ROLLOUT FROM ASSEMBLY BUILDING PLAY | HI-DEF
VIDEO: ENDEAVOUR HOISTED FOR ATTACHMENT TO TANK PLAY | HI-DEF
VIDEO: CRANE ROTATES ENDEAVOUR VERTICALLY PLAY | HI-DEF
VIDEO: ENDEAVOUR MOVES TO ASSEMBLY BUILDING PLAY | HI-DEF
VIDEO: ORION AND ARES ROCKET PROGRESS REPORT PLAY
SUBSCRIBE NOW

John Glenn Mission Patch

Free shipping to U.S. addresses!

The historic first orbital flight by an American is marked by this commemorative patch for John Glenn and Friendship 7.
 U.S. STORE
 WORLDWIDE STORE

Final Shuttle Mission Patch

Free shipping to U.S. addresses!

The crew emblem for the final space shuttle mission is available in our store. Get this piece of history!
 U.S. STORE
 WORLDWIDE STORE

Celebrate the shuttle program

Free shipping to U.S. addresses!

This special commemorative patch marks the retirement of NASA's Space Shuttle Program. Available in our store!
 U.S. STORE
 WORLDWIDE STORE

Anniversary Shuttle Patch

Free shipping to U.S. addresses!

This embroidered patch commemorates the 30th anniversary of the Space Shuttle Program. The design features the space shuttle Columbia's historic maiden flight of April 12, 1981.
 U.S. STORE
 WORLDWIDE STORE

Mercury anniversary

Free shipping to U.S. addresses!


Celebrate the 50th anniversary of Alan Shephard's historic Mercury mission with this collectors' item, the official commemorative embroidered patch.
 U.S. STORE
 WORLDWIDE STORE

Fallen Heroes Patch Collection
The official patches from Apollo 1, the shuttle Challenger and Columbia crews are available in the store.
 U.S. STORE
 WORLDWIDE STORE




INDEX | PLUS | NEWS ARCHIVE | LAUNCH SCHEDULE
ASTRONOMY NOW | STORE

ADVERTISE

© 2014 Spaceflight Now Inc.