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The 5-amp circuit breaker was replaced with a 7-amp circuit breaker to prevent excessive tripping. 

The event diagram in Figures 6-4 and  6-5  maps the hazards, risk assessment, and attempts to mitigate this accident. 

As this accident demonstrates, for the pilot of an experimental aircraft, assessing risk goes beyond the self-assessment illustrated in the IMSAFE method. Hazard identification, risk assessment, and its mitigation starts much earlier. The construction method of manufacture and the materials used impose a certain inherent risk that may not be apparent until an adverse event occurs. Unfortunately, hindsight is of limited value to the aircraft passengers and pilot, but do provide others a better understanding of risk and its insidious nature. 

The risk assessment matrix in Figure 6-6  can provide lessons from this accident. The vertical scale relates to the likelihood of something happening, while the horizontal scale indicates impact upon safety of the flight. 

While impact damage precluded the National Transportation Safety Board (NTSB) from determining the cause of the fire for the aircraft involved in this accident, the final report discusses the possibility that one of the motors to the seat overheated and ignited the seat cushion. They attributed this possibility to the circuit breaker issue as well as the past instance of the circuit breaker tripping when a large occupant sat in the seat. 

It is probable that the installation of the replacement seat started a chain of events diagramed above that led to a fatal accident. The three hazards associated with the seat are discussed more fully below: 

1. Effect of weight on the aircraft weight and balance and its downstream performance—a seat with three motors adds significant weight on one side to the aircraft. Even with weight allowances, aircraft performance would be affected. 

