Background: During an IMSA race pit stop, the quick-release refueling rig nozzle failed to detach from the race car as the driver was waived onto the track and attempted to leave the pits. As the car pulled away, the fueling hose ruptured, spilling gasoline onto the hot exhaust of the car and igniting a fiery conflagration in the car pit area that injured the pit crew member operating the rig.
What We Did: To analyze the accident, an exemplar fueling rig was purchased and modified. A Plexiglas car fitting (the so-called “plug”) was machined in the MARS shop to allow inspection of the connecting device of the rig while it was operating. The complexity of the fuel rig nozzle and its interlocking features made it difficult to explain the working features of the device to Jurors and other attorneys in ways that they could readily envision so the plexiglas part was used for visualization. Using the nozzle and plexiglass fixture made a straightforward demonstration understandable. The rig showed that there was a defect in the fuel nozzle, causing the sticking of the release mechanism and the accident. Photos at right show the complete model, plexiglas plub and fuel nozzle.