With engineers working hard on processing Endeavour (STS-127) and Discovery (STS-128), while at the same time preparing for the arrival of Atlantis from the Dryden Flight Research Center sometime early next week, NASA mission managers are looking ahead on the Shuttle manifest – conducting the Launch Site Flow Requirements (LSFR) review for Endeavour’s early 2010 flight, STS-130/20A.
STS-130 Pre-launch Campaign:
The first of five scheduled missions in 2010, Endeavour’s STS-130/20A flight will see the delivery and installation of the final U.S. module to the International Space Station (ISS).
This module, the Node-3 and adjoining Cupola unit, is currently undergoing processing for flight in the Space Station Processing Facility (SSPF) at the Kennedy Space Center. Node-3, named “Tranquillity” following an online naming contest, arrived from the Thales Alenia Space Italia (TAS-I) in Italy last week and was lifted into its processing stand in the SSPF on Tuesday, May 26.
Node-3 will spend the next few weeks undergoing arrival checkouts in the SSPF before being loaded with ammonia in mid June. Currently, processing schedules indicate that Node-3 will be mated with Cupola for launch on July 16 before officially being turned over from ESA/TAS-I to NASA on October 30.
Node-3 hatch closure for flight is expected on December 7 with transfer into the Payload Transport Canister on January 9, 2010. Node-3 and Cupola are scheduled to be transported to Pad 39A on January 12 with installation into Endeavour’s payload bay on January 18.
Payload interface testing in Endeavour’s payload bay is scheduled for January 20 with payload bay door closure for flight on January 27 and a scheduled launch on February 4.
Additionally, Endeavour will undergo a unique processing flow for launch.
Assuming a nominal End-of-Mission for STS-127 on or around June 29, 2009, Endeavour will go through approximately 152 days of processing in OPF-2 (Orbiter Processing Facility 2) before rolling to the VAB for mating with External Tank (ET 134) on December 9.
Rollout to launch pad 39A is currently scheduled for December 16 with 28 pad processing days, 12 contingency days, and 11 holiday days assessed to launch on February 4.
STS-130 will be the 24th flight of Endeavour and the 130th overall flight of the Space Shuttle Program. Endeavour will use Solid Rocket Booster set BI-141 and Reusable Solid Rocket Motor set 109.
The launch vehicle will be stacked on MLP-2 in VAB High Bay 3. This mission is the third scheduled flight of the Operational Increment (OI) 34 Flight Software.
Endeavour’s six person crew will consist of Commander George Zamka, Pilot Terry Virts, MS1 Kay Hire, MS2/FE Stephen Robinson, MS3 Nicholas Patrick, and MS4 Robert Behnken.
Modifications for Endeavour:
During Endeavour’s OPF flow for STS-130, technicians and engineers will perform two major modifications to NASA youngest orbiter. The first of these modifications relates to the Inconel Thermal Barrier redesign of the Rudder Speed Brake (RSB) spring tabs.
“Installs redesigned Rudder Speed Brake inconel thermal barrier tabs to improve strength of the tab attachment,” notes the 90 page LSFR presentation available for download on L2.
This redesign comes after an inconel tab liberation event during Discovery’s STS-124 mission last June.
Furthermore, after Endeavour’s STS-126 flight last November, post-flight inspections of the Rudder Speed Brake revealed that seven inconel tabs were missing despite improved ground processing and inspection procedures prior to launch.
This new redesign effort will “reduce the moment arm and stress to the spot welds, and will provide a secondary mechanical attachment,” notes the LSFR.
The second modification to Endeavour pertains to O2 Crossover Valve Signal Talkback. The LSFR document noted that this procedure “modifies Orbiter electrical configuration for the O2 crossover valves to provide valve position indication.”
The nitrogen/oxygen (N2/O2) control panel supports O2 and N2 flow to the crew cabin and also provides oxygen to the crew Launch Escape Suits (LES).
The O2 crossover valves are also required to be in the open position to enable crew breathing through the Advanced Crew Escape Suit.
The presentation notes that “current Orbiter configuration provides only switch scan instrumentation which verifies power applied to valve but not position indication (of the valve).”
A failure of the valve in the closed position could result in a loss of oxygen to the LES.
The new valve position indication will be displayed to the Flight Crew on the N2/O2 control panel. This will provide a reliable method for verifying that the O2 crossover valve is in the open position.
To accomplish this modification, “Electrical modification (will require) repinning the connector at the N2/O2 control panel and reworking the MDM and signal conditioners in the avionics bay.”
This will also provide visibility of the valve position for ground monitoring, which is a Launch Commit Criteria requirement.
Payload Clearance Concerns:
As done with all shuttle flights, mission planners have identified a series of points (34 total) along the perimeter of Node-3 that have less than 1” dynamic clearance with the side of Endeavour’s payload bay.
All of these low clearance areas were identified as being greater than 0.5” expect of one, which was determined to have a “dynamic interference of 0.4-inches.” This area is located near the J6YY connector and MLI (Multi-layer Insulation) blanket to the Shuttle Remote Manipulator System arm.
All other areas of Node-3 were determined to have a static clearance of 2.15” or greater. Nevertheless, there is a fair amount of work remaining to complete official assessment of all clearance issues.
Foremost, the DPA (Data Processing Assembly) measurement of Node 3 at the end of May to measure the LTA connector with and without the MLI blanket is still required, as is an optical measurement of Endeavour in order to formalize the official CHIT document for STS-130.
The optical measurement of Endeavour’s payload bay cannot be completed until after her return from STS-127 at the end of June. Therefore a final assessment of dynamic clearance issues with Node-3 and the Payload Bay will not be completed until mid-September.
Furthermore, the LSFR document notes that no new Cargo Integration Hardware (CIH) is required for STS-130. Likewise, all CIH, bridges, and latches are available to support STS-128, STS-129, and STS-130 on their currently planned launch dates.
L2 members: Documentation – from which most of the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size