Static Fire Holddowns & Thrust Structure

As the ground structures team lead at the Yellow Jacket Space Program, it was my responsibility to design a hold-down system to keep the rocket on the ground during static fires. The project had to be completed from start to finish in three months. The initial design consisted of water-jetted plates, steel feet plates mounted to the ground with earth anchors, and pins holding the rocket down from its thrust structure. This design was optimal because the rocket's thrust was directly taken to the ground from the thrust structure, without adding stresses on the stringers, airframe, and fluid components. 

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At the last minute, after the hold-downs had been manufactured and assembled, a change to the vehicles quick disconnect location was made. This caused the launch rail to turn 30 degrees with respect to the gantry and static fire hold-downs. This change caused an interference problem with the hold-downs and the launch rail legs.

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I led the team to a quick turnaround solution and the hold-downs were redesigned, remanufactured, and reassembled within 10 days. In the new design, a welded steel structure attaches to the launch rail backbone and connects to the thrust structure. With the new design, I was able to place loadcells into the thrust structure to measure the rocket's thrust during static fire. The loadcells were placed between steel plates attached to four linear bearings. I conducted additional calculations to ensure that the launch rail's backbone was not significantly weakened by the interface holes.