D. B. Cooper - Theories and Conjectures

Theories and Conjectures

In the years since the hijacking the FBI has periodically made public some of its working hypotheses and tentative conclusions about the case, drawn from witness testimony and the scarce physical evidence.

The official physical description remains unchanged and is considered reliable. Flight attendants Schaffner and Mucklow, who spent the most time with Cooper, were interviewed on the same night in separate cities, and gave nearly identical descriptions: 5 feet 10 inches (1.78 m) to 6 feet 0 inches (1.83 m) tall, 170 to 180 pounds (77 to 82 kg), mid-40s, with close-set piercing brown eyes. Passengers and other eyewitnesses gave very similar descriptions.

Agents believe that Cooper was familiar with the Seattle area and may have been an Air Force veteran, based on testimony that he recognized the city of Tacoma from the air as the jet circled Puget Sound, and his accurate comment to Mucklow that McChord Air Force Base was approximately 20 minutes' driving time from the Seattle-Tacoma Airport—a detail most civilians would not know, or comment upon. His financial situation was very likely desperate: Extortionists and other criminals who steal large amounts of money nearly always do so, according to experts, because they need it urgently; otherwise, the crime is not worth the considerable risk. (A minority opinion is that Cooper was "a thrill seeker" who made the jump "just to prove it could be done.")

Agents theorize that he took his alias from a popular Belgian comic book series of the 1970s featuring the fictional hero Dan Cooper, a Royal Canadian Air Force test pilot who took part in numerous heroic adventures, including parachuting. (One cover from the series, reproduced on the FBI web site, depicts test pilot Cooper skydiving in full paratrooper regalia.) Because the Dan Cooper comics were never translated into English nor imported to the US, they speculate that he may have encountered them during a tour of duty in Europe. Tom Kaye's Cooper Research Team (see Ongoing investigation) has suggested the alternative possibility that Cooper was Canadian, and found the comics in Canada, where they were also sold. They note his specific demand for "negotiable American currency", a phrase seldom if ever used by American citizens; since witnesses stated that Cooper had no distinguishable accent, Canada would be his most likely country of origin if he were not an American.

The FBI task force believes that Cooper was a careful and shrewd planner: He asked for four parachutes to encourage the assumption that he might compel one or more hostages to jump with him, thus ensuring he would not be deliberately supplied with sabotaged equipment. The amount and form of the ransom (if sources are correct that he specified 20-dollar bills) appear also to have been carefully calculated in advance: 50- or 100-dollar bills would have drawn attention and been too difficult to pass, and a larger quantity of 20-dollar bills would have been too heavy and bulky for his jump.

Cooper was apparently quite familiar with the 727-100 aircraft: It was the ideal choice at the time, not only for its aft airstair, but also the high, aftward placement of all three engines, allowing a reasonably safe jump without risk of immediate incineration by jet exhaust. It had "single-point fueling" capability, a recent innovation which allowed all tanks to be refueled rapidly through a single fuel port. It also had the ability (unusual for a commercial jet airliner) to remain in slow, low-altitude flight without stalling; and Cooper knew how to control its air speed and altitude without entering the cockpit, where he could have been overpowered by the three pilots. In addition, Cooper was familiar with important details, such as the appropriate flap setting of 15 degrees (which was unique to that aircraft), and the typical refueling time. He knew that the aft airstair could be lowered during flight—a fact never disclosed to civilian flight crews since there was no situation on a passenger flight that would make it necessary—and that its operation, by a single switch in the rear of the cabin, could not be overridden from the cockpit. He may even have known, particularly if he served in Vietnam or had friends who did, that the Central Intelligence Agency had been using 727s to drop agents and supplies behind enemy lines in Vietnam.

The Bureau feels strongly that he lacked crucial skydiving skills and experience. "We originally thought Cooper was an experienced jumper, perhaps even a paratrooper," said Special Agent Carr, the current chief investigator. "We concluded after a few years this was simply not true. No experienced parachutist would have jumped in the pitch-black night, in the rain, with a 200-mile-an-hour wind in his face, wearing loafers and a trench coat. It was simply too risky. He also missed that his reserve 'chute was only for training, and had been sewn shut—something a skilled skydiver would have checked." He also failed to bring or request a helmet, chose to jump with the older and technically inferior of the two primary parachutes supplied to him, and jumped into a minus-70-degree (F) wind chill.

Assuming Cooper was not a paratrooper, and was an Air Force veteran, Carr believes he could have been an aircraft cargo loader. Such an assignment would have given him knowledge and experience in the aviation industry; and because Air Force loaders throw cargo out of flying aircraft, they wear emergency parachutes in case they accidentally fall out. The rudimentary jump training loaders receive would have given Cooper a working knowledge of parachutes—but "not necessarily sufficient knowledge to survive the jump he made."

The Bureau has argued from the beginning that Cooper did not survive his jump. "Diving into the wilderness without a plan, without the right equipment, in such terrible conditions, he probably never even got his 'chute open," said Carr. Even if he did land safely, agents contend, survival in the mountainous terrain would have been all but impossible without an accomplice at a predetermined landing point, which would have required a precisely timed jump, necessitating, in turn, cooperation from the flight crew. There is no evidence that Cooper had any such help from the crew, nor any clear idea where he was when he jumped into the overcast darkness.