In 1984, NASA Dryden Flight Research 

Center and the Federal Aviation Administration teamed up in a unique flight 

experiment called the Controlled Impact 

Demonstration to test a promising fuel 

additive for retarding or suppressing fire 

in a real-world aircraft crash-landing scenario. When blended with standard Jet-A 

fuel, the FM-9 additive, a high-molecularweight, long-chain polymer, had demonstrated the capability to inhibit ignition 

and flame propagation of the released 

fuel in simulated impact tests.

An obsolete Boeing 720 four-engine 

airliner was obtained from the FAA for 

the project, which would conclude with 

an intentional crash-landing of the remotely piloted aircraft into several steel 

structures set up on Rogers Dry Lake at 

Edwards Air Force Base to rip open wing 

fuel tanks. 

This anti-misting kerosene with the 

FM-9 additive could not be introduced 

directly into a gas turbine engine due 

to several potential problems, such as 

clogging of filters. The modified fuel had 

to be restored to nearly Jet-A standard 

before being introduced into the engine 

for burning. This restoration was accomplished on the Boeing 720 using a device 

called a degrader that was installed on 

each of the aircraft’s four Pratt & Whitney 

JT3C-7 engines.

In addition to the fuels research, NASA 

Langley Research Center was involved in 

a structural loads measurement experiment that included having instrumented 

dummies occupy seats in the passenger 

cabin. The plane was also instrumented 

for a variety of other impact-survivability 

experiments, including new seat designs, flight data recorders, galley and 

stowage-bin attachments, cabin fireproof 

materials, and burn-resistant windows. 

Before the final flight on Dec. 1, 1984, 

more than four years of effort were required to set up final impact conditions 

considered survivable by the FAA. NASA 

Controlled Impact Demonstration

EC84-31806
National Aeronautics and Space Administration

Dryden Flight Research Center

P.O. Box 273

Edwards, CA 93523-0273

Voice 661-276-3449 FAX 661-276-3566

NASA Facts

FS-2009-02-003-DFRC

Dryden developed the remote piloting techniques 

necessary for the Boeing 720 to be flown with no 

flight crew on board; General Electric installed and 

tested the degraders for each engine; and the FAA 

refined the fuel with the FM-9 anti-misting additive. 

A series of 14 preliminary flights was made to introduce the modified fuel incrementally into some of 

the fuel tanks and engines while engine performance was monitored. During the 14 flights made 

with safety pilots on board, the Boeing 720 was 

controlled remotely by a pilot in a ground-based 

console for 16 hours and 22 minutes, including 10 

takeoffs, 69 controlled landing approaches, and 13 

landings on the abort runway.

On the morning of Dec. 1, 1984, the remotely controlled Boeing 720 transport took off from Edwards 

on the 15th and final flight in the program. The fuel 

tanks were filled with 76,000 pounds of the modified Jet-A fuel and all engines ran normally from 

start-up to impact during the nine-minute flight. 

Flown by NASA research pilot Fitzhugh Fulton from 

the NASA Dryden Remotely Controlled Vehicle 

Facility, the airliner made a left-hand departure and 

climbed to an altitude of 2,300 feet. The flight plan 

called for the aircraft to touch down wheels-up on 

a specially prepared runway on the east side of the 

dry lakebed with its wings level and exactly on the 

center line, allowing the fuselage to remain intact 

as the wings were sliced open by eight steel posts 

cemented into the lakebed.

The Boeing 720 began a descent to landing with 

its landing gear retracted, with final approach along 

a roughly 3.8-degree glide slope. As the jetliner 

descended through the decision height of 150 feet 

above ground level, the aircraft was slightly to the 

right of the desired path, but appeared to have 

enough altitude for the remote pilot to maneuver it 

back to the center line of the runway. Data acquisition systems had been activated, and the aircraft 

was committed to impact. 

As the Boeing 720 neared the lakebed, its left wing 

dropped and contacted the ground first, short 

of the wing cutters. This caused the nose of the 

airliner to swing to the left as it skidded on the 

lakebed surface at about a 45-degree angle. As a 

result, one wing cutter struck the inboard engine 

on the right wing, destroying the engine and causing a massive fuel leak that immediately burst into 

flame. The airliner continued to yaw to the left until 

it was nearly sideways, causing the damaged right 

wing to break off and fold over and the fuselage to 

be engulfed in a massive fuel-fed fireball. The fire 

took more than an hour to fully extinguish. 

The Controlled Impact Demonstration marked the 

end of FAA attempts to order airlines to use the 

anti-misting additive in airliner fuel. Although proponents argued that the modified fuel prevented a 

hotter, more catastrophic fire during the test, FAA 

requirements for the additive were cancelled. 

The demonstration underscored an often-overlooked aspect of aeronautical research. Although 

small-scale ground tests had indicated that the 

anti-misting additive would be effective in reducing post-crash fires, the full-scale demonstration 

in a real-world flight environment showed that the 

modified anti-misting fuel was ineffective in reducing the propagation or intensity of fire. 

Despite this result, much useful safety-related 

data was obtained during the Controlled Impact 

Demonstration. Cameras inside the airliner showed 

crash dummies being shaken and small panels 

falling during the crash-landing, although the seats 

remained attached to the floor. The new seat designs, flight data recorders, galley and stowage-bin 

attachments, fireproof materials and windows were 

tested under real-world conditions. Research data 

from the project in these areas yielded new data on 

impact survivability that helped the FAA establish 

new rules regarding fire prevention and fire-retardant materials.