Monday, November 2, 2009

Shuttle Program managers outline mission priorities for STS-129

Monday, November 2, 2009
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With Space Shuttle Atlantis now officially targeting a launch on November 16, Space Shuttle Program (SSP) managers have – via Flight Readiness Review (FRR) documentation – reviewed and approved all flight plans and mission operations that will be undertaken during Atlantis’ 12-day flight to the International Space Station (ISS).

Mission Overview:

After nearly two years, Atlantis is finally set to make her return to International Space Station (ISS) duty with the STS-129 mission in two week’s time.

After last visiting the ISS in February 2008 during the STS-122 mission, Atlantis’ STS-129 flight will deliver over 29,458 lbs of external hardware and spares to the ISS via the Express Logistics Carriers (ELCs) 1 & 2.

The 11+1+2 day mission is expected to launch at 2:27:54p.m. on November 16 with a confirmed second attempt possible at 2:02:12p.m. on November 17.

Currently, those are the only two days available for NASA and Shuttle Atlantis because of an Eastern Range constraint relating to the expected launch of a Delta IV rocket carrying a WGS satellite on November 19 at 7:45p.m.

If, through negotiations with the Air Force and Department of Defense, NASA is able to secure additional launch days for Atlantis, the remaining options prior to the hard close of the window due to a Solar Beta Angle Cutout are: 1:39:40p.m. on November 18, 1:13:58p.m. on November 19, and (with the elimination of the +1 mission day) 12:51:27p.m. on November 20.

During countdown operations, Atlantis’ five Nitrogen tanks will be fully loaded (with Nitrogen transfer to the ISS beginning on FD-4) and her five Cryo tank sets will be fully loaded as well.

Based on vehicle performance and mission during needs, Atlantis will have 66-hours of pad hold time for her cryo consumables – with the limiting consumable being hydrogen.

This pad hold time is based on the GLACIER unit (that Atlantis will return to Earth from the ISS) being installed and powered up from FD-7 through End Of Mission and the fact that the “primary logics and drivers” will be powered from prelaunch through docking.

However, this pad hold time can be extended to as much as 96-hours by powering-down certain Orbiter systems after docking operations. The ability to extend the pad hold time limits may be necessary given the short duration of Atlantis’ launch window and the desire to have as many launch attempts as possible in the November window.

During the mission, Atlantis will spend six full days docked to the ISS, with three scheduled EVAs (spacewalks) staged from the Station’s Quest Airlock, 30-hours of Middeck transfer options from Atlantis to ISS, and the transfer of Nicole Stott from the ISS crew to the Shuttle crew.

Flying on Atlantis will be Commander Charlie “Scorch” Hobaugh, Pilot Barry “Butch” Wilmore, Mission Specialist-1(MS-1) Leland Melvin, MS-2/Flight Engineer Randy “Komrade” Bresnik, MS-3 Michael Foreman, and MS-4 Robert Satcher.

Atlantis’ crew will meet ISS Commander Frank DeWinne (from the European Space Agency), Flight Engineer-1 Maxim “Max” Suraev, Flight Engineer-2 Nicole Stott, Flight Engineer-3 Roman Romanenko, Flight Engineer-4 Robert Thirsk (from the Canadian Space Agency), and Flight Engineer-5 Jeffrey Williams.

For STS-129 (which carries an ISS mission designation of ULF-3), Atlantis will haul the ELC-1 and ELC-2 payload pallets to the ISS along with the S-band Antenna Support Assembly (SASA) and the MISSE (Materials for International Space Station Experiment) 7A and 7B payloads.

Attached to ELC-1 will be one Battery Charge/Discharge Unit, one Control Moment Gyro, one Nitrogen Tank Assembly, one Pump Module, one Ammonia Tank Assembly, one Plasma Contactor Unit, one Latching End Effector, and two empty payload PFRAMs for future payload use.

Riding uphill on ELC-2 will be one Control Moment Gyro, one Nitrogen Tank Assembly, one Pump Module, one High Pressure Gas Tank, on MT/TUS Reel Assembly, one Cargo Transport Container (carrying seven Type-V RPCMs, one Type-II RPCM, and one CRPCM), MISSE-7 Attach Hardware/Adapter Plates, one empty Orbital Replacement Unit PFRAM, and one empty payload PFRAM.

ELC-1 will be berthed to the P3 truss’ lower UCCAS and ELC-2 will be berthed to the S3 truss’ upper outboard PAS.

Mission Priorities:

As with all Space Shuttle missions, STS-129’s mission objectives have been divided into four categories based on their priority status – as outlined in FRR documentation available on L2.

In all, there are seven Category I objectives for the mission, including docking Atlantis to PMA-2 (Pressurized Mating Adaptor 2 and performing all mandatory safety briefings) and transferring Nicole Stott from the ISS to Atlantis.

Also included in the Category I objectives list are the completion of preparations and check-out tasks for the Soyuz capsule undocking at the beginning of December, the installation and activation of the ELC-1 and ELC-2 pallets, the transfer of water from Atlantis to ISS, and the transfer and stowage of critical ULF-3 items on the priority transfer list.

Additionally, there are six Category II objectives, including the transfer of the SASA to the Z1 truss location and the application of heaters and operational power to the device, the installation, activation, and checkout of the MISSE 7A and 7B Payload Experiment Carriers (PECS) onto ELC-2, and the removal of a Node-1 handrail and replacement of the NH3 line routing bracket.

The repositioning of the LAN connectors and Micro-Meteoroid Orbiting Debris shield tie downs on the Functional Cargo Block, the mating of a Node-3 channel primary power connector to the S0 truss, and the installation of Port bulkhead feed throughs and intra-module ventilation mod kit on Node-1 round out the Cat II objectives.

The Category III objectives – 14 in all – include transferring Nitrogen from Atlantis to ISS, replacing the Airlock Battery Charge Modules, transferring and installing spare High Pressure Gas Tanks from ELC-2 to the ISS Airlock, relocating Floating Potential Measurement Unit and a Video Stanchion Support Assembly from Camera Port 2 (CP-2) to CP-6, deploying the S3 truss Lower Outboard PAS, and installing a Node-1 avionics kit.

A reboost of the ISS if Atlantis’ consumables allow and a photographic survey of the exterior of the ISS during undocking and fly-around are also included on the Category III objectives list.

Rounding out the Mission Priority list are the Category IV objectives. Consisting mainly of get ahead tasks or “would be nice” activities, the 11 objectives include ISS structural life validation and extension DTO (Detailed Test Objective) during ELC-1 and ELC-2 installation, ISS reboost operations, and Atlantis/ISS undocking operations. Performing payloads of opportunity and approved EVA get-ahead tasks are also included on the Cat IV objectives list.

Mission Profile:

Under nominal mission conditions, Atlantis’ launch, power insertion, SRMS (Shuttle Remote Manipulator System) power up and checkout, NC-1 burn, and FD-1 downlinks/downloads (i.e. the ET umbilical well photos, hand-held ET video, and Wing Leading Edge System data) will all be accomplished on FD-1.

Flight Day-2 will include the now-normal Thermal Protection System inspection, rendezvous preparations, the NC-2 and NC-3 burns, and the grapple of the ELC-1 with the SRMS.

FD-3 will see Atlantis’ crew perform their rendezvous and docking with Space Station Alpha, Nicole Stott’s transfer from ISS to Atlantis, ELC-1 unberth, handoff to the SSRMS (Space Station RMS), and installation to the PAS, and EVA-1 campout operations.

EVA-1 (including SASA transfer and installation, SGANT cable routing, POA lube, and Japanese Experiment Module RMS lube), internal transfer operations from Atlantis to ISS, and the installation of the Node-1 mod Kit will all be accomplished on FD-4.

If needed, the Focused Inspection of Atlantis’ TPS will be performed on FD-5, as will internal transfer operations and EVA-2 campout/preparations.

On FD-6, ELC-2 will be installed onto the ISS, the AIS/ARISS antennas will be installed, the FPMU relocated, and the S3 Truss Nadir Outboard PAS deployed on EVA-2.

FD-7 will be dominated by an Off-Duty period for the crew, internal transfer operations, and EVA-3 preparations. The HPGT transfer to the Station’s Airlock, the MISSE PECs transfer to ELC-2, and S3 truss Upper Inboard PAS deployment will all be accomplished on FD-8, as will internal transfer operations.

FD-9 will be a partial Off-Duty day for the crew, followed by final transfer operations to Orbiter Atlantis, and Hatch Closure between the two vehicles. Undocking of Atlantis, ISS fly-around, and TPS late inspections are all on tap for FD-10.

FD-11 (Thanksgiving Day in the U.S. based on a November 16 launch) will be spent preparing Atlantis for reentry and landing operations, with the first landing opportunity of the mission coming on FD-12 – with a deorbit burn on orbit 171.

While the above is based on a nominal mission timeline, the possibility always exists that a technical problem with one of Atlantis’ systems could force mission controllers to invoke a Minimum Duration Flight.

If that should occur early in the mission, the STS-129 flight would play out as such.

Flight Days-1, -2, and -3 would proceed per the nominal mission timeline.

FD-4 would see the transfer of mandatory critical items per the ULF-3 Transfer List and EVA-1 would be altered to the following: SASA transfer and installation, SGANT cable routing, and the retrieval of both TSAs and the MISSE PECs contents and their relocation inside the Airlock for stowage.

FD-5 would still contain the Focused Inspection (if required) and the continuation of the transfer of mandatory critical items per the ULF-3 Transfer List.

FD-6 would see the unberth, hand-off, and installation of the ELC-2, the completion of the transfer of mandatory and critical items per ULF-3 Transfer List, and Hatch Closure between Atlantis and ISS.

Undocking, fly-around, TPS late inspection, OBSS (Orbiter Boom Sensor System) berth/stow and SRMS power down would occur on FD-7, with Cabin stow and reentry preparations on FD-8 and landing on FD-9.

Nevertheless, the possibility also exists that Atlantis’ mission could be extended by utilizing the +1 day in the 11+1+2 day mission.

“The following will be considered in utilizing the ‘+1′ docked day that is available,” notes the MOD presentation to the SSP FRR.

“In the event of a FD-4 Rendezvous, the +1 day will be used and a normal mission timeline executed.”

Also, should a Focused Inspection be required — and that Focused Inspection last longer than the allotted 3-hours – the +1 day may be used to maximize the mission objectives.

Additionally, the +1 day could be used to add a “contingency EVA” in order to complete all Category I objectives or to add a docked day to complete all Intra-Vehicular Activity Category II objectives.

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