SilkAir Flight 185

Aircraft The aircraft involved was a Boeing 737-36N with serial number 28556, registered as 9V-TRF, and powered by two CFM56-3B2 engines. Having completed its maiden flight on 27 January 1997, the aircraft was delivered to SilkAir on 14 February, 10 months before the crash. At the time of the accident, it was the newest aircraft in SilkAir's fleet and had accumulated more than 2,200 flight hours in 1,300 cycles. This was the first and only fatal hull loss for SilkAir in the airline's history. Among those killed in the crash was Singaporean model and author Bonny Hicks. == Flight ==

Carrying 97 passengers and a crew of seven, the Boeing 737 departed Jakarta's Soekarno–Hatta International Airport's runway 25R at 15:37 local time (08:37 UTC) for an 80-minute flight to Singapore's Changi Airport. At the controls were Captain Tsu Way Ming (41) of Singapore, a former A-4 Skyhawk pilot, and First Officer Duncan Ward (23) of New Zealand. Generally fair weather was expected for the route, except for some thunderstorms near Singkep Island, south of Singapore. At 15:53, the crew reported reaching the cruise altitude of FL350 and was cleared to proceed directly to PARDI, and to report abeam Palembang. The cockpit voice recorder (CVR) ceased recording at 16:05. At 16:10, air traffic controllers informed the flight that it was abeam Palembang and instructed the aircraft to maintain FL350 and to contact Singapore Control upon reaching PARDI. First Officer Ward acknowledged this call. At 16:11, nearly 6 minutes after the CVR ceased recording, the flight data recorder (FDR) also stopped recording. Flight 185 remained level at FL350 until it started a rapid and nearly vertical dive around 16:12. While descending through , parts of the aircraft, including a great extent of the tail section, started to separate from the aircraft's fuselage due to high forces arising from the nearly supersonic dive. ==Investigation and final report==

The accident was investigated by the Indonesian NTSC, which was assisted by expert groups from the US, Singapore, and Australia. Around 73% of the wreckage (by weight) was recovered, partially reconstructed, and examined. Both of the aircraft recorders, the CVR and the FDR, were retrieved from the river and their data were extracted and analyzed. The investigators tested 20 different simulations for various equipment-failure scenarios, and found that the only scenario that matched the actual radar trajectory of the descent and crash of the flight was a high-speed steep dive commanded by one of the pilots. Furthermore, the investigators had found the trim jackscrew for the horizontal stabilizer, which revealed that flight inputs from one of the pilots had moved the stabilizer from level flight to a full nose-down descent. The American NTSB, which also participated in the investigation, concluded that the evidence was consistent with a deliberate manipulation of the flight controls, most likely by the captain. In a letter to the NTSC dated 11 December 2000, the NTSB wrote: Geoffrey Thomas of The Sydney Morning Herald said, "a secret report confirmed that the Indonesian authorities would not issue a public verdict because they feared it would make their own people too frightened to fly." Santoso Sayogo, an NTSC investigator who worked on the SilkAir 185 case, said that the Indonesian investigators submitted a report which was similar to that of the NTSB's conclusion but were overruled by their boss. (his share-trading showed trading of more than one million shares and his securities-trading privileges had been suspended 10 days before the accident due to nonpayment), Investigations later revealed that his total assets were greater than his liabilities, although his liquid assets could not cover his immediate debts; his monthly income was less than his family's monthly expenditure; and he had some outstanding credit card debts. Tsu was formerly a Republic of Singapore Air Force pilot, and had over 20 years of flying experience in the older T/A-4S Skyhawks, as well as the newer T/A-4SU Super Skyhawks. His last appointment was instructor pilot of a Skyhawk squadron. CVR and FDR deactivation The CVR and FDR stopped recording minutes before the abrupt descent, but not at the same time. On 8 September 1994, USAir Flight 427, a 737-300, crashed near Pittsburgh, Pennsylvania, killing 132 people. Four more incidents occurred where a 737 rudder PCU malfunction was suspected. The Seattle Times devoted a series of 37 articles to Boeing 737 loss-of-control malfunctions. The accident occurred in the middle of a controversy over the NTSB's role in accidents caused by the rudder control unit. During the investigation of Flight 427, the NTSB had discovered that the PCU's dual servo valve could jam, as well, and deflect the rudder in the opposite direction of the pilots' input, due to thermal shock, caused when cold PCUs are injected with hot hydraulic fluid. As a result of this finding, the FAA ordered the servo valves to be replaced and new training protocol for pilots to handle unexpected movement of flight controls to be developed. The FAA ordered an upgrade of all Boeing 737 rudder control systems by 12 November 2002. ==Aftermath==

'' the day after the crash Lawsuits SilkAir paid USD$10,000 compensation to each victim's family, the maximum under the Warsaw Convention. Boeing also paid an undisclosed amount of compensation. In July 2001 six families began court proceedings against SilkAir for damages, based on the allegation that the crash was caused by the pilot, after each had rejected a compensation offer of $200,000 (£143,000). In October 2001 the claims were turned down by a Singapore High Court judge who ruled that "the onus of proving that flight MI185 was intentionally crashed has not been discharged." The findings of the private investigation were then taken to the Los Angeles Superior Court in 2004 where the jury, which was not allowed to hear or consider the NTSB's conclusions about the accident, found that the crash was caused by a defective servo valve in the plane's rudder. Parker-Hannifin spokesperson Lorrie Paul Crum stated that a federal law disallowed them from using the NTSB final report as evidence in the company's favor during the lawsuit. The lawyer representing the plaintiffs, Walter Lack, stated that the law only disallowed using the NTSB report's conclusion and suggestions, while statements of fact are admissible. USC §1154 (Discovery and use of cockpit and surface vehicle recordings and transcripts) states: "No part of a report of the Board, related to an accident or an investigation of an accident, may be admitted into evidence or used in a civil action for damages resulting from a matter mentioned in the report." Memorials A memorial for the victims was erected at the burial site, which is located within the Botanical Gardens near Palembang. Another memorial is located at Choa Chu Kang Cemetery in Singapore. Dramatisation The Discovery Channel Canada / National Geographic TV series Mayday (also called Air Crash Investigation or Air Disasters) dramatised the accident in a 2012 episode titled Pushed to the Limit (broadcast in some countries as Pilot Under Pressure). The episode argues Captain Tsu may have taken the opportunity of leaving the cockpit for tripping the CVR circuit breaker to turn off the CVR. The documentary claimed that the accident aircraft's FDR had failed to record 60 out of the 296 parameters for periods lasting between 10 seconds and 10 minutes in the 25 hours preceding the crash. as a close friend of the artist, Xu Chue Fern, was killed on the flight. == See also ==