ATK have won a $62.5 million award from the Lockheed Martin-owned Orion contract – awarded via subcontractor Orbital Sciences Corporation – to develop the main motor element of the Orion Launch Abort System (LAS).
The LAS – a tower which contains solid propellants – would be used to pull the Orion capsule away from a failing Ares I launch vehicle, either at the pad, or during ascent.
Huge amounts of VSE related insider news and presentations – THE most comprehensive place to follow Ares/Orion development – are available for download on L2. See list at the end of this article.
The primary role of the LAS is to save the crew during the ‘three stages’ of an abort, the first involving the firing of the Orion away from a failing vehicle on the launch pad to a safe distance, before deploying the parachutes on the Orion, for a landing in the Atlantic ocean within a 3450 ft radius due east of the launch pad.
The second stage of an abort is noted as ‘mid altitude’ – which has a different characteristic when compared to pad abort. This stage of abort works for up to 150,000 ft, involving the LAS remaining on the vehicle after firing the Orion safely away from the failing vehicle until the point of drogue chute deployment, which become necessary at that altitude.
The final stage of abort, which would still require the LAS, is at an altitude of between 150,000 ft and 300,000 ft – the latter being the point the LAS would be jettisoned on a nominal flight.
The Ares I pad will also have an option of another form of escape, via the Rollercoaster Emergency Egress System (EES).
The LAM (Launch Abort Motor) is not a conventional solid rocket motor; it is a reverse flow motor with four nozzles mounted on the forward end. Once ignited, the LAM produces over a half-million pounds of thrust, pulling the crew module away from the launch vehicle within milliseconds of notification.
ATK has conducted three sub-scale static tests of the reverse flow motor. Two additional sub-scale tests for Orbital are planned this summer.
Advanced technologies – such as the innovative reverseflow nozzle for the abort motor – is ‘a true departure from Apollo era designs,’ noted MSFC’s Stephen Gaddis, deputy manager of the LAS recently, speaking about how Orion’s LAS will be a less harrowing ride compared to Apollo. ‘The reverse-flow nozzle receives fuel injection from underneath, but exhaust gases are rotated 155 degrees to reverse their direction.
‘This prevents the abort motor from washing the capsule shield with flame as it fires. The reverse-flow nozzle also will cut the weight compared to the Apollo-era design.
Under the terms of the contract, ATK will design, develop, produce, test and deliver the launch abort motor (LAM), the largest of three propulsion units integrated into the LAS. The contract includes four full-scale static test units and eight deliverable motors to Orbital for pathfinders, test flights and program support. Orbital is subcontracted to Lockheed Martin who is the prime contractor for Orion.
‘The LAS is a critical system that allows the astronaut crew to safely separate from the launch vehicle in the event of an emergency during launch pad operations and ascent,’ said Mike Kahn, ATK vice president of Space Launch Systems. ‘We have the necessary skills and experience to support Orbital in the development of this vital capability.’
NASA engineers have been looking at three LAS systems, namely the Multiple External (x4) Service Module (SM) Abort Motor concept, the Crew Module Strap On Motors (x4) concept, and the In-Line Tandem Tractor (Tower) concept – with the latter currently baselined into Ares I/Orion design.
The favored Tandem Tractor (Tower) LAS design comprises of a Nose Cone, Attitude Control Motor (Eight Nozzles), Canard Section (Stowed Configuration), Jettison Motor (Four Aft, Scarfed Nozzles), Interstage, Abort Motor (Four Exposed, Reverse Flow Nozzles), Adapter Cone, and Boost Protective Cover (BPC). This is the system that is favored in the overall Ares I baseline.
This is still an on-going process, with the latest Orion – the new 606 design – retaining the larger LAS tower, although on-going weight problems with Ares I/Orion may see this evolve further.
A recent evaluation of the possibility of using the LAS to assist Orion’s ascent targets – touched upon in an expansive LAS presentation on L2 – has been withdrawn as unviable, as the vehicle would require structural strengthening, which would ultimately increase the weight past anything gained by the LAS firing.
Selection of L2 Resources For Ares I, V and Constellation: Updates Constellation launch schedule through to Orion 15. Orion Seat test photos. New ML Graphic and info. New Ares V graphic and baseline data. Large collection of hi res Orion paracute drop tests. SIX Part Series of Ares I Upper Stage Graphical Overviews. DAC-1C DDD Vast Slides on Vehicle Design. ATK First Stage Presentation. 39B Lightning Towers Slides. DAC-1C Departure points to DAC-2 Upper Stage Graphcs (Many Changes).
Orion/CEV Display Layout Presentation (40 pages). ATK figures on the 5-Seg Booster weight for CLV. Weather Shield (Rain Shield) for Orion on the pad. New Super hi-res images of Ares I. ATK Cutaway graphics of Ares I – perspective and axonometric – Feb 1. Ares I/Orion CxP 72031 Requirements Validation Matrix Information. CEV Paracute Assembly System (CPAS) Presentation.
Orion Launch Abort System (LAS) overview presentation. Major changes to Ares I Upper Stage – expansive details and data. Ares I/Orion CxP 72031 Requirements Validation Matrix Information. Saturn Twang Test Video for use with Ares I-1R. CLV Umbilical Trade Matrix XLS.
Vehicle interfaces for the DAC 1C version of Orion Ares – Jan 3. Ares I-1R Test Flight Plan (full outline) Presentation. Ares I-1 timeline and modification expanded info. Ares I troubleshooting latest. Ares I Reference Trajectory. Boeing’s STS to Ares – Lessons Learned Presentation. Latest Ares I and Ares V baseline Configuration image and data. CLV DAC-1C (Changes to CLV Upper Stage).
Ares I-1: Four Seg+Dummy ‘Tuna Can’ stage. Ascent Developmental Flight Test Presentation. CLV Pad 39B Handover Info and Latest. New images of CLV on top of new MLP and LUT. Lockheed Martin CEV/Orion Updates. Constellation news updates. ATK figures on the 5-Seg Booster weight for CLV.
90 Minute Video of Constellation all hands meeting. CLV TIM Meeting Information. CLV/CaLV Infrastructure, Timelines and Information. Escape System Trade Study Presentation.
CEV-CLV Design Analysis Cycle Review (DAC-2) Presentation. Constellation SRR updates. CLV Stick – Troubleshooting/Alternatives/Updates. New CEV Images (include abort mode). Flight Design and Dynamics Division CEV update. CLV Mono-propellant RCS system. CEV pressurisation system review. CLV/CEV Configuration Images. The 2×3 Seg SRB Crew Launch Vehicle Option Presentation…plus more.