With Space Shuttle Endeavour now well into her OPF (Orbiter Processing Facility) flow for her triple duty requirements as LON (Launch On Need) vehicle for STS-119 and STS-125 and her primary mission on STS-127, the Program Requirements Control Board (PRCB) has completed the Delta Launch Site Requirements Review (DLSRR) for STS-127, a critical step toward the mission’s eventual launch.
While STS-127’s launch date currently remains in a fluid state until the STS-125/HST SM4’s launch date is finalized in the coming weeks, technicians around the United States are preserving all options regarding the mission’s launch, which could occur anytime between May 15 to mid July.
Current milestone charts indicate that Endeavour’s turnaround flow will end on April 14 when she will be mated to her External Tank.
In the unlikely event that Discovery became disabled during STS-119, Endeavour’s LON mission would launch on May 13 with a four person subset of her primary seven member crew: Commander Mark Polansky, Pilot Doug Hurley, Flight Engineer Julie Payette, and mission specialists Chris Cassidy, Dave Wolf, Thomas Marshburn, and Timothy Kopra.
Also, according to the January 8 Milestone Interface Chart, Endeavour’s tank – ET-131 – will arrive on dock at KSC on March 1, and is undergoing no processing issues – according to reports from the Michoud Assembly Facility (MAF) in New Orleans.
The 15+1+2 day mission to the International Space Station (ISS) will see Endeavour launch off of Mobile Launch Platform #3 with a full set of Cryo, GN2 (gaseous nitrogen), Aft RCS (Reaction Control System), and OMS (Orbital Maneuvering System) tanks.
STS-127 will be the 23rd flight of Endeavour and the fourth and final scheduled flight of the OI-33 operating software – which first debuted on Endeavour’s STS-126 mission last November.
Also proposed during the DLSRR are the three SSMEs (Space Shuttle Main Engines) that will power Endeavour to orbit. The engines, in numerical order, are engines 2045, 2060, and 2054. Engine 2045 last flew aboard STS-118 in August 2007 while engine 2054 flew with Endeavour on her last mission, STS-126 in November 2008.
For STS-127, Endeavour’s primary payload will be the 2J/A payload package for the ISS. The 2J/A package includes the Japanese Experiment Module – Exposed Facility (JEM-EF) and the Japanese Experiment Logistics Module – Exposed Section (ELM-ES) as well as the Integrated Cargo Carrier – Vertical Light Deployable (ICC-VLD).
Attached to the ICC-VLD will be six P6 truss batteries (which will be part of the P6 battery R&R activities during one of the mission’s EVAs), a Linear Drive Unit, Pump Module #2, and a Space to Ground Antennae – all of which will be transferred to ESP-3 (External Stowage Platform-3) during an EVA.
In addition to these primary payloads, Endeavour will fly with DRAGONSAT (Dual RF Autonomous GPS On-Orbit Navigator Satellite), MAUI (Maui Analysis of Upper-Atmospheric Injections), ANDE-2 (Atmospheric Neutral Density Experiment-2), SEITE (Shuttle Engine Ion Turbulence Experiment), and SIMPLEX (Shuttle Ionospheric Modification with Pulsed Local Exhaust).
With this information in hand, mission planners have determined that Endeavour’s Ascent Performance Margin will be 1,190lbs assessed for launch on May 15.
Endeavour’s OPF Flow:
As part of Endeavour’s turnaround flow in OPF-2, one mandatory modification and one mandatory update the mission kit will be worked prior to OV-105’s rollover to the VAB. The mandatory modification relates to a Fastener Removal Verification.
“Verification of Fastener Removal from Overhead Luminous Ceiling Panel required,” notes the 96 page PRCB presentation, available for download on L2.
The fastener removal is a necessary modification based on the requirement to fly Multiple Headset Adapters on future missions.
In addition to this modification, technicians will also revise Airlock Upper Hatch decals and reconfigure some external Trajectory Control System (TCS) blankets, install middeck partition lexan covers, and complete the fleet wide APU GN2 Quick Disconnect Heater modifications on OV-105.
Moreover, the update to the mission kit is in regard to the Bay 4 Longeron bridges for the JEM-EF.
“Bay 4 longeron bridges V073-340103-001 and -002 are required for JEM-EF on STS-127. The only flight pair is manifested to support the forward end of Super Lightweight Integrated Carrier (SLIC) currently installed on (Atlantis for) STS-125,” notes the DLSRR presentation.
The delay to STS-125 is directly effecting the installation of the Bay 4 bridges into Endeavour.
“Second ‘original build’ pair (of Bay 4 bridges) was flown on and recovered after STS-107 but has been deemed unusable.”
The Orbiter Project Office (OPO) has currently set into motion two options to mitigate this issue. The first is to modify a set of Bay 3 Longeron Bridges made from Titanium. The second is to build a new set of Bay 4 bridges from Aluminum.
The first option has an estimated completion date of January 30 while the second has an estimated completion date of January 16.
Further updates the mission kit include “expanding PL retention active latch control capability, installation of the DragonEye Detailed Test Objective (DTO) box with flash LIDAR and data acquisition unit on the ODS truss, and reconfiguring external airlock ducting.”
DragonEye (DE) – for SpaceX’s Dragon capsule – will be installed onto Endeavour’s Orbiter Docking System (ODS).
“SpaceX DE is one of two leading candidates for investigation of a flash Light Intensification Detection and Ranging (LIDAR) relative navigation sensor for the SpaceX Dragon vehicle,” notes the PRCB presentation.
The DragonEye DTO will be mounted to the Trajectory Control System-1 (TCS-1) carrier assembly on Endeavour’s ODS starboard location. TCS-2 is mounted to the port location.
Moreover, technicians will install a refurbished MO10W Panel which will replace the MO10W panel flown on STS-126 which contained a faulty N2/O2 crossover valve. The updated MO10W panel contains new design flow meters.
Furthermore, technicians will be replacing several hardware items including: Windows 1 and 6, Fuel Cell #2, the right hand ET door Power Distribution Unit, the Main Propulsion System GH2 (gaseous hydrogen) Flow Control Valves (FCV) and 2-inch line, the Main Landing Gear environmental seals, and the -Y star tracker.
Several time cycle components will also be replaced during Endeavour’s flow. These include Payload Bay Vent Door filters, Payload Bay Vent Liner filters, and GPS batteries.
For Endeavour’s Thermal Protection System (TPS), 36 cavities were identified at the time the DLSRR was conducted; however, the presentation estimates that a total of 107 TPS removals will be necessary during the orbiter’s flow.
Currently, OPF workers are tracking two potential concerns: the delivery of three good Flow Control Valves (FCVs) for Endeavour (expected to be delivered within a month’s time) and the delivery date of ANDE-2.
The PRCB DLSRR presentation goes on to note that if Endeavour should be required for LON operations for STS-119, “the STS-127 Reconfiguration Engineering Products will be updated by the Engineering Order To Follow (EOTF) process.”
For STS-400, “a Program Configuration Waiver will be submitted in March 2009 to document the differences between STS-400 and STS-127 and allow the launch of STS-400 without a MECSLSI update.”
Lastly, Endeavour will be configured for STS-400 at the time of OPF rollout; however, since STS-400 will not carry any mission specific payload, Endeavour’s Payload Bay will be configured to accept the STS-127 payload as soon as Endeavour is officially released from STS-400 operations.
L2 members: All documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.