Solid Rocket Booster Processing Kennedy Space Center SRB Mechanical Engineering NE-M7

KSC – Solid Rocket Booster (SRB) Processing Areas Shuttle Processing and Launch Postflight Hardware Recovery and Evaluation

KSC – Solid Rocket Booster (SRB) Processing Areas Pad VAB RPSF

KSC – Solid Rocket Booster (SRB) Processing Flow Recovery Disassembly and Assessment Design Centers Element Refurbishment and Manufacturing Logistics and Shipping Delivery Offload and Inspect Aft Booster Build RPSF SRB RETRIEVAL SHIP SHUTTLE LANDING HANGAR AF ORBITER PROCESSING FACILITY SRB STACKING Field Joint Mate Leak Test Field Joint Protection System S&A Offload Buildup ET/SRB OPERATIONS INTEGRATED VEHICLE OPS/VAB ET STANDALONE LCC HORIZONTAL PAYLOAD INT PAYLOAD FACILITIES HYPERGOLIC FACILITY VERTICAL PAYLOAD INSTALLATION Launch Pad Ops

Forward Assembly and Aft Skirt arrive from SRB Element in the Assembly Refurbishment Facility (ARF) at KSC. Aft Skirt Parachutes ARF Frustum Forward Assembly Nose Cone Frustum Parachutes Forward Skirt Nose Cone

Segments arrive from ATK in Corrine, Utah in rail cars Segments arrive from ATK in Corrine, Utah in rail cars. The segments go to the Rotation, Processing and Surge Facility (RPSF) at KSC. RPSF

At the Rotation, Processing and Surge Facility (RPSF), the rail cover is removed, propellant grain & metal surfaces inspected, the segments are rotated to vertical, secured on a pallet and stored in the surge facilities. Break-over of the forward segment from horizontal to vertical

Build-up to Aft Booster Configuration (see following charts) At the RPSF, the aft booster is assembled and processed in the build-up stands. Other hardware processed in the RPSF includes: - Stiffener Rings Assembly and Closeouts - Thermal Curtains - External Tank Assembly (ETA) ring and hardware - Thermal Protection System (TPS) closeouts - Systems tunnel and cables installation and closeouts - Heater power cable installation - Nozzle severance cable connection AEC Mate AEC Breakover Aft Skirt Mate Aft Segment Breakover to Vertical Build-up to Aft Booster Configuration (see following charts) Aft Booster Build-up Stand

Pin Retainer Steel Strap Aft Booster Build Stand The aft skirt is placed in the build-up stand and the booster segment is mated. 177 pins are installed and secured with a steel pin retainer strap. The joint is closed out with cork and RT-455 ablative compound. Aft Skirt Mate Pin Retainer Steel Strap Cork Band Aft Booster Build Stand Aft Skirt Clevis

Aft exit cone is assembled to the forward exit cone at the RPSF. Phenolic mating surfaces are primed with DC1200 primer prior to assembly. Primary and secondary seals (O-rings) are installed. Exit cone is raised on an elevator and floated on an air bearing for mating. The joint is bolted with 96 fasteners. Leak test is performed at 83 and 30 psig with the mass flow meter prior to joint RTV backfill. The joint gap is backfilled (injected) with RTV silicone sealant as part of thermal barrier system. Primary Seal Secondary Seal Phenolic RTV Thermal Barrier AEC Mate Phenolic Aft Skirt Not Shown for Clarity Aft Exit Cone

Surge buildings protect hardware from elements (rain, wind, etc.) If needed, the aft booster will be put into surge for storage. The SRM transporter transfers the aft booster from the RPSF to the surge or the Vehicle Assembly Building (VAB) for the stacking operations. Surge buildings protect hardware from elements (rain, wind, etc.) Not climate controlled Segments have weather proof covers on top RPSF Surge VAB

The segment is connected to the beam and the 325-ton crane in the transfer isle of the VAB. Circularity measurements, tang preps, metal parts inspections, abrade J-leg, and assemble/connect curtain.

The aft booster segment is lifted from the transfer isle to the high bay of the VAB to be connected to the Mobile Launch Platform (MLP). The booster is bolted to the hold down post of the MLP with a frangible nut that separates at launch.

At KSC, the center and forward segments are stacked At KSC, the center and forward segments are stacked. When two segments are mated at KSC, this joint is called a field joint. The SRB forward assembly mated. Then, all field joints are all closed out in the VAB. SRB Forward Assembly Forward Segment Forward Field Joint Forward Center Segment Center Field Joint Aft Center Segment Aft Field Joint Aft Booster

All the field joints are configured with a tang and clevis design with a capture feature. The 3 O-rings and J-leg help prohibit a combustion gas leak at the joints. Field joint is a clevis and tang configuration with 177 pins Three alignment slots/pins ensure correct segment clocking Tang “capture feature” and insulation “j-leg” added during redesign Tang Tang capture feature “captures” inner clevis leg to limit seal surface movement (joint rotation) during motor pressurization Insulation j-leg prohibits combustion gas from reaching seals Capture Feature Field Joint Example Clevis Inner Clevis Leg Insulation J-leg

For a segment mate, the segment is lowered over the SRB stack For a segment mate, the segment is lowered over the SRB stack. The field joint assembly fixture (FJAF) acts as a “shoehorn” to align the tang/clevis and prevent flat-on-flat metal conditions. Leak test of the joint and the vent port plug are the final acceptance of a successful joint mate. Field joint mate with 3 feet between the segments. FJAF O-rings PSA Application Field joint mate with 1/8” between the segments. Segment mates require a controlled environment within the curtain room. Also, the controlled area requires personnel to wear flames, eyes-only hoods, gloves and meet maximum static levels.

Each field joint is closed out with the field joint protection system (FJPS). The FJPS provides thermal protection, weather protection and retains joint pins. Cork Joint Temperature Sensor Heater Retainer Strap and Thermal Barrier Joint Heater Field joint after mate, before FJPS RT-455 Ablative Cork Pin Retainer Band RT-455 Ablative Field joint with FJPS

The forward assembly is mated to the forward segment and also closed out with FJPS. Since no propellant is exposed in this mate, a controlled environment is not needed. Forward Skirt Cork Band Fwd Segment Forward Skirt JPS Pin Retainer Strap Forward Skirt Joint

The systems tunnel, cables, heater power cables, and linear shaped charge (LSC) are all assembled and closed out. In addition, TPS, cabling and closeouts are completed in other areas of the boosters. Forward and Center Field Joint Tunnel Closeout Tunnel Cover RT-455 Systems Tunnel Closeout LH side (fwd 3 segments) Heater Power Cables Cork

After the boosters are assembled, the external tank (ET) is then brought over from the ET check-out cell in the VAB for the ET/SRB mate.

Next, the orbiter is mated to the ET with the boosters supporting the weight of the whole shuttle.

The crawler transports the MLP and the shuttle to the pad where all processing is completed.

After launch, the boosters separate at around L+128 seconds After launch, the boosters separate at around L+128 seconds. The boosters continue to climb to around 42 miles high. Then, boosters tumble until the drogue shoot deploys at 1600 feet, which orientates the boosters upright. The main parachutes deploy at 6300 ft to slow down the boosters to impact the ocean at about 60 mph. Before impacting the ocean, the aft exit nozzle separates to prevent deformation on the reusable motor.

The Liberty Star and Freedom Star each retrieve a booster in the ocean to tow it back to Hanger AF at KSC.

The boosters are received at Hanger AF and evaluated for any off nominal conditions in the post-flight assessment.

Every aspect of the boosters is inspected and compared to past post-flight data. The segments are disassembled and sent back to ATK and USA.