That Time we Intentionally Crashed a Boeing 720 Into the Desert
CID (Controlled Impact Demonstration) was a venture undertaken by NASA and the FAA to obtain data from an intentionally crashed Boeing 720.
One of the experiment’s main goals was the testing of fire-suppressing fuel additive FM-9 (picture above illustrates how well that went). When FM-9 is combined with jet-fuel, it creates antimisting kerosene — known to deter ignition and spreading of flames.
The experiment also counted on crash test dummies, which are full-scale anthropomorphic test devices (ATDs); basically, they simulate human bodies (accurate to height, weight, and dimensions) during controlled traffic collisions.
It took NASA and the FAA 4 years to prepare for the crash test. The aircraft went through 14 test flights, during which:
- Engine performance (running on antimisting kerosene) was tested.
- Remote piloting techniques were perfected. Throughout the 14 flights, the aircraft was controlled remotely by a pilot on the ground, though there were also safety pilots onboard.
- The blend of antimisting kerosene was tested and enhanced.
The crash site included eight cemented cutters (nicknamed Rhinos) to slice the wings open without harming the fuselage.
The day of the test finally came about on December 1, 1984. The 720 took off from Edwards Air Force Base in California and headed for the crash site.
Moments before the crash, the aircraft had steered slightly to the right of the desired path. The remote pilot tried correcting its course, but it was too late.
Data acquisition systems were on; the aircraft was committed to the impact.
The wings were meant to be level at impact, but the left-wing was low, thus making the first contact with the ground.
When the aircraft smashed into the ground, one of the Rhinos sliced through the right-wing, cut through the fuselage, and into engine number 3. The engine kept running for 1/3 of a rotation, providing a heat source and igniting a massive fire.
The fire completely undermined efforts to test the antimisting kerosene and took over an hour to put out.
Despite the failure in testing FM-9, NASA considered the test a success due to the crash data that was collected.
It has been estimated that 23–25% of the 720’s capacity of 113 people could have survived the crash.
The test also made flying safer as the FAA changed two requirements based on the results. They implemented new flammability standards for seat cushions, and required mechanic fastening for floor proximity lightning as the adhesive ones used in the test appeared to have been detached.