Capitol International Airways flight C2C3 / 26
| Capitol International Airways flight C2C3 / 26 | |
|---|---|
.jpg) An identical DC-8 from Capitol International Airways |
|
| Accident summary | |
| Accident type | Agreement from the runway after aborted take-off, brake failure |
| place |
Anchorage Airport , Alaska , United States
|
| date | November 27, 1970 |
| Fatalities | 47 |
| Survivors | 182 |
| Aircraft | |
| Aircraft type |
Douglas DC-8-63CF
|
| operator |
Capitol International Airways
|
| Mark |
N4909C
|
| Departure airport |
McChord Air Force Base , Washington , United States
|
| 1. Stopover |
Anchorage Airport , Alaska , United States
|
| 2. Stopover |
Yokota Air Base , Japan
|
| Destination airport |
Cam Ranh Bay , South Vietnam
|
| Passengers | 219 |
| crew | 10 |
| Lists of aviation accidents | |
On November 27, 1970, a Douglas DC-8-63CF of Capitol International Airways had an accident on Capitol International Airways flight C2C3 / 26 while taking off from Anchorage Airport . The machine was on a charter flight on behalf of the US Department of Defense and was supposed to transport soldiers to the Cam Ranh Bay military base in South Vietnam . 47 of the 229 people on board were killed in the accident.
background
At the time of the accident, 1970, the Vietnam War had been raging in East Asia, which had been going on since 1955 , in which South Vietnam fought against North Vietnam and the National Front for the Liberation of South Vietnam . While North Vietnam was supported by the Soviet Union and the People's Republic of China , South Vietnam was joined by a coalition led by the United States and supported by South Korea , Thailand , Australia , the Philippines , New Zealand, and the Republic of China .
The USA participated in the Vietnam War with a large number of troops; In January 1969, 543,400 US Army soldiers were stationed in South Vietnam. Commercial aircraft from civil airlines were used for regular exchanges between US troops. The United States Department of Defense awarded the charter contracts through public tenders. The airline Capitol International Airways won a contract to transport military personnel on behalf of the Military Airlift Command from McChord Air Force Base, south of Tacoma, Washington , to Cam Ranh Bay and to bring returning soldiers back to the United States.
Capitol International Airways planned to use a Douglas DC-8 to fulfill the order. For the flight to Cam Ranh Bay, stopovers for refueling in Anchorage and at Yokota Air Base had been planned. When taking off from Anchorage on the onward flight to Japan, the plane crashed.
plane
The machine that crashed was a one and a half year old Douglas DC-8-63, which was assembled at the Douglas plant in Long Beach , California and which was rolled out on May 27, 1969. The machine was acquired on July 2, 1969 by the leasing company CIT Corporation; On the same day, the machine was delivered to Capitol International Airways as the lessee of the machine. The DC-8 was certified with the aircraft registration N4909C . The aircraft had the factory number 46060; it was the 472nd Douglas DC-8 from ongoing production. The DC-8 was equipped with four Pratt & Whitney JT3D-7 engines. At the time of the accident, the machine had run 4,944 hours.
crew
There was a crew of ten on board. The cockpit crew consisted of a flight captain, a first officer, a flight engineer and a navigator.
- The 48-year-old flight captain William G. Reid had signed his employment contract with Capitol International Airways on January 1, 1955. Reid had type ratings for the Lockheed Constellation , Curtiss C-46 and Douglas DC-8 aircraft . The captain had 14,650 hours of flight experience, 5,740 hours of which with the DC-8.
- James A. Downs, 55, was hired by Capitol International Airways on May 28, 1962. He had type ratings for Douglas DC-3 , Douglas DC-4 and Lockheed Constellation aircraft . Downs had 13,500 hours of flight experience, 2,057 of which with the Douglas DC-8.
- The 41-year-old flight engineer Edward W. Fink flew for Capitol International Airways since May 12, 1964. He had 10,000 hours of flight experience, 2,000 of which with the Douglas DC-8.
- The 53-year-old navigator Robert D. Leonard worked for Capitol International Airways since February 28, 1966. He had over 14,000 hours of flight experience, 2,500 of which he had completed in the cockpit of the Douglas DC-8.
- The six flight attendants Marlene Faistauer, Alexandra Plommer, Barbara M. Ogden, Alice B. Mendez, Britta E. Thomsen and Birgitta I. Ekelund were cabin crew members on board.
Passengers
219 military personnel officially took the flight, six of whom were family members of military employees. The passengers had all boarded at McChord Air Force Base. The majority of the passengers were young, athletic male soldiers.
Flight history
The flight began when the aircraft took off from McChord Air Force Base at 12:04 p.m. on November 27. The first flight segment to Anchorage was routine; there were no noticeable incidents. At 3:32 p.m., the aircraft landed on runway 06L at Anchorage Airport. The captain stated that he braked moderately when the aircraft was coasting and actuated the thrust reverser in order to bring the heavy aircraft to a stop on the icy runway. The braking effect was weak to moderate. When rolling to the parking position, only slight braking maneuvers were made. After the machine was brought into parking position and connected to the gate, the parking brake was released.
During the stopover, a mechanic inspected the machine as part of a tour. In this context, he also inspected the tires and certified that they were in good condition, had the correct inflation pressure and did not reveal any abnormalities. The machine was then defrosted with ethylene glycol .
Weather
By the time the machine began to be processed at the gate, darkness had already fallen, as the days in the winter months in Alaska are very short. At the same time, a light sleet set in. There was a light wind with visibility of five miles (about eight kilometers); the cloud cover was 1,600 feet (488 meters) above the ground. The runway was covered with a thin layer of ice.
the accident
Shortly before 5 p.m. local time, the machine rolled to runway 06R. The machine had almost its maximum take-off weight, but with the 10,000-foot runway (approx. 3,048 meters) there was enough distance available to accelerate to the required take-off speed of 153 knots (approx. 283 km / h). First Officer Downs was supposed to steer the engine as it lifted off, while Captain Reid was supposed to release the brakes and operate the thrust levers. After the take-off clearance, Reid held the brakes on until he had increased the engine power to eighty percent. He then released the brakes and gave full thrust while Downs kept the machine aligned along the runway during takeoff. The machine appeared to be accelerating normally, but the decision speed was reached a little later than usual. The machine then accelerated more slowly, but the take-off speed was reached 1500 feet (approx. 457 meters) before the end of the runway. Downs then rotated the aircraft's nose , but for some reason the machine did not take off. Six seconds later the plane rolled over the end of the runway with the nose still raised above the runway. Reid took the thrust back and tried to stop the machine, but it plowed its way through navigational equipment behind the runway and skidded over a drainage channel, causing the DC-8 to break apart. The kerosene from both wing tanks ignited as the machine skidded until it came to a stop 3,000 feet past the end of the runway.
Rescue operation
Reid, uninjured in the accident, left the aircraft through the cockpit window and hurried to the passengers' aid. When he found that the door to the passenger cabin was blocked, he ran back to the cockpit and pulled Downs, Fink and Leonard outside.
Victim
Despite the quick reaction of the flight crew, 46 passengers and the flight attendant Birgitta I. Ekelund were killed in the flames.
Accident investigation
The accident was investigated by the National Transportation Safety Board (NTSB). Upon inspection of the runway, investigators found that there were unusually large amounts of tire debris and pieces of tire along the length of the runway. On the other hand, no noticeable tire tracks were found along the route from the parking position to the runway. From the starting point, there were clear tire tracks along the entire runway, with the first worn tire parts already being found 500 feet (approx. 152 meters) from the starting point. After an acceleration distance of 4000 feet (approx. 1219 meters), all the landing gear tires on the port side had burst, after 8000 feet (approx. 2438 meters) all of the starboard side tires too . Passengers said they heard several loud explosions during the take-off run and suspected that the landing gear tires had burst one after the other at this point. No explosions could be heard on the recordings and no vibrations could be heard, but the findings of tire parts on the runway and their condition supported the statements of the passengers. When inspecting the tires that had not burst, it was found that they had a flat brake , which indicated that the wheels were locked at the start and had not turned. The brakes appeared to be fine and the parking brake was in the released position. No evidence could be found that there was a malfunction in the braking system.
The NTSB turned to NASA with the request to research the running properties of aircraft tires as part of a series of tests. The investigators feared that the tires could generate such a low coefficient of friction on icy ground that the wheels would not turn even after the parking brake was released. The series of experiments refuted the fears; the wheels turned normally during the tests. However, the tests produced an interesting finding. The original tests were carried out with viable tires on ice surfaces and a significant coefficient of friction could be measured. However, the blocked tires of the DC-8 were so heated by the forces acting on them during take-off that they immediately melted any ice under them. The machine therefore skidded over water. This in turn reduced the coefficient of friction to such an extent that a take-off run must have felt quite routine in the initial phase. Thanks to this special form of aquaplaning , the machine was initially able to accelerate normally with only a slight delay, even with locked wheels. Analyzes of the flight data recorder showed that the acceleration behavior up to a speed of about 100 knots (approx. 185 km / h) was almost normal. Then the friction coefficient increased due to the dissolution of the tires, which had a negative effect on the acceleration values. The maximum speed that the machine reached was one knot (about 1.85 km / h) below the take-off speed.
The investigators were of the opinion that the wheels should have started to turn at some point, despite all the circumstances, unless the parking brake was activated. However, no evidence of activation of the parking brake could be found and both pilots were certain that the brake had been released before the take-off run. The investigators came to the conclusion that the accident had been caused by an unspecified misalignment in the hydraulic system, which contributed to the fact that all the wheels were blocked. It could not be determined what the origin of this misalignment was. The hydraulic system itself could not be examined for this because it was destroyed in the fire. Although the flight data recorder reported values that indicated a significant decrease in acceleration performance after reaching a speed of 100 knots (approx. 185 km / h), the behavior of the crew was not assessed as being decisive for the accident. Due to the gradual occurrence of the acceleration problem, they could not have been aware of the real cause.
context
It can be assumed that the failed start of the machine prevented an even more serious accident. If the plane had taken off, the burning tires could have led to fires in all landing gear shafts after being drawn in and thus to a similar accident as on Nigeria Airways flight 2120 .
See also
Individual evidence
- ↑ a b c d e f g h i j k l m n AIRCRAFT ACCIDENT REPORT / CAPITOL INTERNATIONAL AIRWAYS, INC. DC-8-63F, N4909C Anchorage, Alaska November 27, 1970 , National Transportation Safety Board , March 29, 1972.
- ↑ a b c d Accident report in the Aviation Safety Network
- ↑ a b c d e f g h i j k l m Civil Aviation Disasters - Capitol N4909C , Pilotfriend
- ↑ Operating history of the machine on planespotters.net
Coordinates: 61 ° 10 '4.4 " N , 149 ° 56' 12.6" W.