D. B. Cooper - the only unsolved air-piracy in America

Passengers embarking via an air-stair of a Lufthansa B727

D. B. Cooper is a media epithet popularly used to refer to an unidentified man who hijacked a Boeing 727 aircraft in the airspace between Portland, Oregon, and Seattle, Washington, on November 24, 1971, extorted $200,000 in ransom (equivalent to $1,160,000 in 2014), and parachuted to an uncertain fate. Despite an extensive manhunt and an ongoing FBI investigation, the perpetrator has never been located or positively identified. The case remains the only unsolved air piracy in American aviation history.

The suspect purchased his airline ticket using the alias Dan Cooper, but due to a news media miscommunication he became known in popular lore as "D. B. Cooper". Hundreds of leads have been pursued in the ensuing years, but no conclusive evidence has ever surfaced regarding Cooper's true identity or whereabouts. Numerous theories of widely varying plausibility have been proposed by experts, reporters, and amateur enthusiasts. The discovery of a small cache of ransom bills in 1980 triggered renewed interest but ultimately only deepened the mystery, and the great majority of the ransom remains unrecovered.

While FBI investigators have stated from the beginning that Cooper probably did not survive his risky jump, the agency maintains an active case file - which has grown to more than 60 volumes - and continues to solicit creative ideas and new leads from the public. "Maybe a hydrologist can use the latest technology to trace the $5,800 in ransom money found in 1980 to where Cooper landed upstream," suggested Special Agent Larry Carr, leader of the investigation team since 2006. "Or maybe someone just remembers that odd uncle."

Hijacking

The incident began mid-afternoon on Thanksgiving eve, November 24, 1971, at Portland International Airport in Portland, Oregon. A man carrying a black attaché case approached the flight counter of Northwest Orient Airlines. He identified himself as "Dan Cooper" and purchased a one-way ticket on Flight 305, a 30-minute trip to Seattle, Washington.

FBI's wanted poster of Cooper

Cooper boarded the aircraft, a Boeing 727-100 (FAA registration N467US), and took seat 18C (18E by one account, 15D by another) in the rear of the passenger cabin. He lit a cigarette and ordered a bourbon and soda. Eyewitnesses on board recalled a man in his mid-forties, between 5 feet 10 inches (1.78 m) and 6 feet 0 inches (1.83 m) tall. He wore a black lightweight raincoat, loafers, a dark suit, a neatly pressed white collared shirt, a black necktie, and a mother of pearl tie pin.

Flight 305, approximately one-third full, took off on schedule at 2:50 pm, local time (PST). Cooper passed a note to Florence Schaffner, the flight attendant situated nearest to him in a jumpseat attached to the aft stair door. Schaffner, assuming the note contained a lonely businessman's phone number, dropped it unopened into her purse. Cooper leaned toward her and whispered, "Miss, you'd better look at that note. I have a bomb."

The note was printed in neat, all-capital letters with a felt pen. It read, approximately, "I have a bomb in my briefcase. I will use it if necessary. I want you to sit next to me. You are being hijacked." Schaffner did as requested, then quietly asked to see the bomb. Cooper cracked open his briefcase long enough for her to glimpse eight red cylinders ("four on top of four") attached to wires coated with red insulation, and a large cylindrical battery. After closing the briefcase, he dictated his demands: $200,000 in "negotiable American currency"; four parachutes (two primary and two reserve); and a fuel truck standing by in Seattle to refuel the aircraft upon arrival. Schaffner conveyed Cooper's instructions to the cockpit; when she returned, he was wearing dark sunglasses.

Cpt. Scott, F/O Rataczak, F/A Mucklow and S/O Anderson

The pilot, William Scott, contacted Seattle-Tacoma Airport air traffic control, which in turn informed local and federal authorities. The 36 other passengers were informed that their arrival in Seattle would be delayed because of a "minor mechanical difficulty". Northwest Orient's president, Donald Nyrop, authorized payment of the ransom and ordered all employees to cooperate fully with the hijacker. The aircraft circled Puget Sound for approximately two hours to allow Seattle police and the FBI time to assemble Cooper's parachutes and ransom money, and to mobilize emergency personnel.

Schaffner recalled that Cooper appeared familiar with the local terrain; at one point he remarked, "Looks like Tacoma down there," as the aircraft flew above it. He also mentioned, correctly, that McChord Air Force Base was only a 20-minute drive from Seattle-Tacoma Airport. Schaffner described him as calm, polite, and well-spoken, not at all consistent with the stereotypes (enraged, hardened criminals or "take-me-to-Cuba" political dissidents) popularly associated with air piracy at the time. Tina Mucklow, another flight attendant, agreed. "He wasn't nervous," she told investigators. "He seemed rather nice. He was never cruel or nasty. He was thoughtful and calm all the time." He ordered a second bourbon and water, paid his drink tab (and insisted Schaffner keep the change), and offered to request meals for the flight crew during the stop in Seattle.

FBI agents assembled the ransom money from several Seattle-area banks - 10,000 unmarked 20-dollar bills, many with serial numbers beginning with the letter "L" indicating issuance by the Federal Reserve Bank of San Francisco, most carrying a "Series 1969-C" designation - and made a microfilm photograph of each of them. Cooper rejected the military-issue parachutes initially offered by authorities, demanding instead civilian parachutes with manually operated ripcords. Seattle police obtained them from a local skydiving school.

Passengers released

N467US during refuelling at Seattle-Tacoma Airport

At 5:24 pm Cooper was informed that his demands had been met, and at 5:39 pm the aircraft landed at Seattle-Tacoma Airport. Cooper instructed Scott to taxi the jet to an isolated, brightly lit section of the tarmac and extinguish lights in the cabin to deter police snipers. Northwest Orient's Seattle operations manager, Al Lee, approached the aircraft in street clothes (to avoid the possibility that Cooper might mistake his airline uniform for that of a police officer) and delivered the cash-filled knapsack and parachutes to Mucklow via the aft stairs. Once the delivery was completed Cooper permitted all passengers, Schaffner, and senior flight attendant Alice Hancock to leave the plane.

During refueling Cooper outlined his flight plan to the cockpit crew: a southeast course toward Mexico City at the minimum airspeed possible without stalling the aircraft (approximately 100 knots (190 km/h; 120 mph)) at a maximum 10,000 foot (3,000 m) altitude. He further specified that the landing gear remain deployed in the takeoff/landing position, the wing flaps be lowered 15 degrees, and the cabin remain unpressurized. Copilot William Rataczak informed Cooper that the aircraft's range was limited to approximately 1,000 miles (1,600 km) under the specified flight configuration, which meant that a second refueling would be necessary before entering Mexico. Cooper and the crew discussed options and agreed on Reno, Nevada, as the refueling stop. Finally, Cooper directed that the plane take off with the rear exit door open and its staircase extended. Northwest's home office objected, on grounds that it was unsafe to take off with the aft staircase deployed. Cooper countered that it was indeed safe, but he would not argue the point; he would lower it himself once they were airborne.

An FAA official requested a face-to-face meeting with Cooper aboard the aircraft, which was denied. The refueling process was delayed due to a vapor lock in the fuel tanker truck's pumping mechanism, and Cooper became suspicious; but he allowed a replacement tanker truck to continue the refueling - and a third after the second ran dry.

Back in the air

At approximately 7:40 pm the 727 took off with only Cooper, pilot Scott, flight attendant Mucklow, copilot Rataczak, and flight engineer H. E. Anderson aboard. Two F-106 fighter aircraft scrambled from nearby McChord Air Force Base followed behind the airliner, one above it and one below, out of Cooper's view. A Lockheed T-33 trainer, diverted from an unrelated Air National Guard mission, also shadowed the 727 until it ran low on fuel and turned back near the Oregon-California border.

After takeoff Cooper told Mucklow to join the rest of the crew in the cockpit and remain there with the door closed. As she complied, Mucklow observed Cooper tying something around his waist. At approximately 8:00 pm a warning light flashed in the cockpit, indicating that the aft airstair apparatus had been activated. The crew's offer of assistance via the aircraft's intercom system was curtly refused. The crew soon noticed a subjective change of air pressure, indicating that the aft door was open.

Animation showing how Cooper could have left the B727

At approximately 8:13 pm the aircraft's tail section sustained a sudden upward movement, significant enough to require trimming to bring the plane back to level flight. At approximately 10:15 pm Scott and Rataczak landed the 727, with the aft airstair still deployed, at Reno Airport. FBI agents, state troopers, sheriff's deputies, and Reno police surrounded the jet, as it had not yet been determined with certainty that Cooper was no longer aboard; but an armed search quickly confirmed that he was gone.

Theories and conjectures

Operation manual of a B727 air-stair

The FBI task force believes that Cooper was a careful and shrewd planner. He demanded four parachutes to force 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. He chose a 727-100 aircraft because it was ideal for a bail-out escape, due not only to its aft airstair, but also the high, aftward placement of all three engines, which allowed 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 that the Central Intelligence Agency had been using 727s to drop agents and supplies behind enemy lines during the Vietnam War.

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

Airport security

The Cooper hijacking marked the beginning of the end for unfettered and unscrutinized airline travel. Despite initiation of the federal Sky Marshal program the previous year, 31 hijackings were committed in U.S. airspace in 1972, 19 of them for the specific purpose of extorting money. (Most of the rest were attempts to reach Cuba.) In 15 of the extortion cases the hijackers also demanded parachutes. In early 1973 the FAA began requiring airlines to search all passengers and their bags. Amid multiple lawsuits charging that such searches violated Fourth Amendment protections against search and seizure, federal courts ruled that they were acceptable when applied universally, and when limited to searches for weapons and explosives. In contrast to the 31 hijackings in 1972, only two were attempted in 1973, both by psychiatric patients, one of whom intended to crash the airliner into the White House to kill President Nixon.

Aircraft modifications

Cooper vane

A Cooper vane (also sometimes called a "Dan Cooper switch" or "D.B. Cooper device") is a mechanical aerodynamic wedge that prevents the ventral airstair of an aircraft being lowered in flight. Following three hijackings in 1972, the Federal Aviation Administration ordered that Boeing 727 aircraft be fitted with Cooper vanes.The Cooper vane is a very simple device consisting of a spring-loaded paddle connected to a plate. When the aircraft is on the ramp, the spring keeps the paddle perpendicular to the fuselage, and the attached plate does not block the stairway. As the aircraft takes off, the airflow pushes the paddle parallel to the fuselage and the plate is moved underneath the stairway, preventing it being lowered. Once the airflow decreases on landing, the spring-loaded paddle returns to its initial position, thereby allowing the stairs to be lowered again. Although this device was intended to prevent hijackings aboard the 727 and other aircraft with a ventral airstair, many airlines sealed the airstair entirely, never to use it again.

A less-well-known modification mandated as a direct result of the hijacking was the installation of peepholes in all cockpit doors, making it possible for the cockpit crew to observe events in the passenger cabin with the cockpit door closed.

Subsequent history of N467US

In 1978 the hijacked 727-100 aircraft was sold by Northwest to Piedmont Airlines where it was reregistered N838N and continued in domestic carrier service. In 1984 it was purchased by the now-defunct charter company Key Airlines, reregistered N29KA, and incorporated into the Air Force's civilian charter fleet that shuttled workers between Nellis Air Force Base and the Tonopah Test Range during the top-secret F-117 Nighthawk development program. In 1996 the aircraft was scrapped for parts in a Memphis boneyard.

Source:
http://en.wikipedia.org/wiki/D._B._Cooper
http://en.wikipedia.org/wiki/Cooper_vane