damping. The term "phugoid" was coined by Frederick W. Lanchester, the British aerodynamicist who first characterized the phenomenon. He derived the word from the Greek words and to mean "flight-like" but recognized the diminished appropriateness of the derivation given that meant flight in the sense of "escape" (as in the word "fugitive") rather than vehicle flight. Aviation accidents In 1972, an Aero Transporti Italiani Fokker F-27 Friendship, en route from Rome Fiumicino to Foggia, climbing through 13,500 feet, entered an area of poor weather with local thunderstorm activity. At almost 15,000 feet the aircraft suddenly lost 1200 feet of altitude and its speed dropped. It developed phugoid oscillations from which the pilots could not recover. The aircraft struck the ground at a speed of 340 knots. Three crew and fifteen passengers on board were all killed. In the 1975 Tan Son Nhut C-5 accident, USAF C-5 68-0218 with flight controls damaged by failure of the rear cargo/pressure door, encountered phugoid oscillations while the crew was attempting a return to base, and crash-landed in a rice paddy adjacent to the airport. Of the 328 people on board, 153 died, making it the deadliest accident involving a US military aircraft. In 1985, Japan Airlines Flight 123 lost all hydraulic controls after its vertical stabiliser blew off due to an aft pressure bulkhead failure, and went into phugoid motion. While the crew were able to maintain near-level flight through the use of engine power, the plane lost height over a mountain range northwest of Tokyo before crashing into Mount Takamagahara. With 520 deaths, it remains the deadliest single-aircraft disaster in history. In 1989, United Airlines Flight 232 suffered an uncontained engine failure in the #2 (tail) engine, which caused total hydraulic system failure. The crew flew the aircraft with throttle only. Suppressing the phugoid tendency was particularly difficult. The pilots reached Sioux Gateway Airport but crashed during the landing attempt. All four cockpit crewmembers (one an assisting DC-10 captain on the flight as a passenger) and a majority of the passengers survived. Another aircraft that lost all hydraulics and experienced phugoid was a DHL operated Airbus A300B4 that was hit by a surface-to-air missile fired by the Iraqi resistance in the 2003 Baghdad DHL attempted shootdown incident. This was the first time that a crew landed an air transport aircraft safely by only adjusting engine thrust. The 2003 crash of the Helios solar-powered