–256 Canadian Aviation Safety Board (CASB) CASB. Aviation Occurrence Report. Arrow Air.
–256 Planecrashinfo.com. “1985. Accident Details. Arrow Airways…Gander…Dec 12, 1985.”
Narrative Information
CASB Majority Report: Synopsis The aircraft was on an international charter flight from Cairo, Egypt to Fort Campbell, U.S.A., with planned stops at Cologne, Germany and Gander, Newfoundland. During take-off from Gander, the aircraft crashed and burned approximately one-half mile off the departure end of runway 22. All 256 passengers and crew sustained fatal injuries.
“The Canadian Aviation Safety Board was unable to determine the exact sequence of events which led to this accident. The Board believes, however, that the weight of evidence supports the conclusion that, shortly after lift-off, the aircraft experienced an increase in drag and reduction in lift which resulted in a stall at low altitude from which recovery was not possible. The most probable cause of the stall was determined to be ice contamination on the leading edge and upper surface of the wing. Other possible factors such as a loss of thrust from the number four engine and inappropriate take-off reference speeds may have compounded the effects of the contamination.
“History of the Flight On 11 December 1985, Arrow Air Flight MF1285R, a Douglas DC-8-63, U.S. registration N9SOJW, departed Cairo, Egypt on an international charter flight to Fort Campbell, Kentucky (Ky), U.S.A. via Cologne, Germany, and Gander, Newfoundland. On board were 8 crew members and 248 passengers. The flight was the return portion of the second in a series of three planned troop rotation flights originating at McChord Air Force Base (AFB), Washington, U.S.A. and terminating in Fort Campbell. The flight had been chartered by the Multinational Force and Observers (MFO) to transport troops, their personal effects, and some military equipment to and from peacekeeping duties in the Sinai Desert. All 248 passengers who departed Cairo on 11 December 1985 were members of 101st Airborne Division (United States Army), based in Fort Campbell….
“The flight arrived at Gander at 0904. Passengers were deplaned, the aircraft was refueled, trash and waste water were removed, and catering supplies were boarded. The flight engineer was observed to conduct an external inspection of portions of the aircraft. The passengers then reboarded. Following engine start-up, the aircraft was taxied via taxiway “D” and runway 13 to runway 22 for departure. Take-off on runway 22 was begun from the intersection of runway 13 at 1015. The aircraft was observed to proceed down the runway and rotate in the vicinity of taxiway “A”. Witnesses to the take-off reported that the aircraft gained little altitude after rotation and began to descend. Several witnesses, who were traveling on the Trans-Canada Highway approximately 900 feet beyond the departure end of runway 22, testified that the aircraft crossed the highway, which is at a lower elevation than the runway, at a very low altitude.
“Three described a yellow/orange glow emanating from the aircraft. Two of the witnesses testified that the glow was bright enough to illuminate the interior of the truck cabs they were driving. The third attributed the glow to the reflection of the runway approach lighting on the aircraft. Several witnesses observed the aircraft in a right bank as it crossed the Trans-Canada Highway. The pitch angle was also seen to increase, but the aircraft continued to descend until it struck downsloping terrain approximately 3,000 feet beyond the departure end of the runway…
“The aircraft was destroyed by impact forces and a severe fuel-fed fire. All 256 occupants on board sustained fatal injuries….
“Wreckage and Impact Information The aircraft struck downsloping terrain near the top of a wooded hillside, 2,975 feet beyond the departure end of runway 22, a distance of 720 feet to the right of the extended runway centre line. Initial impact with the terrain was a tree strike at an elevation of 279 feet asl. Ground elevation at this point is approximately 240 feet asl.
“From that point, the aircraft continued its descent into the trees; initial ground impact occurred 920 feet beyond the first tree contact.
“The wreckage trail was about 1,300 feet long and 130 feet wide. The trail was on a track of 240 degrees magnetic (M). The mean downslope of the terrain over which the wreckage was spread was seven degrees.
“Two separate and distinct swaths were cut by the aircraft as it initially descended into the tree canopy. Upon investigation, it was apparent that the lower of the two swaths, to the left when viewed in the direction of flight, was cut by the horizontal stabilizer and that the higher swath, to the right side, was cut by the right wing. The tree-swath pattern was consistent with a nosehigh, right-wing-low attitude at impact.
“As the aircraft descended lower into the trees, the different elevations of the two swaths evened out until there was no discernible difference at the point of ground impact.
“Significant portions of the horizontal stabilizer and elevators had separated from the aircraft and were found between the initial tree strike and the point of ground impact. Portions of the right wing tip were also found between these two points. Damage patterns found on the leading edge of the wing tip, stabilizer, and elevator were consistent with a nose-up attitude and slight yaw to the right at impact.
“At ground impact, the right wing sustained extensive damage. Both the number three and number four engines were tom from their pylons. A fuel-fed fire commenced at the impact point of the number four engine and spread down and across the wreckage trail in a diagonal manner toward the left side of the aircraft. The aircraft then began to yaw further to the right, and the empennage separated at the rear pressure bulkhead.
“The remainder of the aircraft continued down the sloping terrain where it struck two rock outcrops, breaking off a substantial portion of the rear fuselage aft of the wings. By this point, the aircraft had yawed approximately 60 degrees to the right. The forward and centre sections of the fuselage then crossed a gravel access road where the left wing, remaining portions of the right wing, and cockpit section separated.
“The centre section of the fuselage continued down the slope for a short distance where it came to rest in a shallow ravine. The lower portion of the wreckage trail was subjected to a severe fuel-fed fire which consumed a substantial portion of the wreckage.
“
“A thorough search of the runway and the area between the runway end and initial impact point was conducted with the assistance of personnel from Canadian Forces Base Gander. No components or debris was located that could have come from the aircraft. There was no evidence that the aircraft tail had touched the runway during the take-off….
“Fire An intense fuel-fed post-crash fire developed. Substantial portions of the aircraft were consumed in the fire. As a result, it was impossible to account for and examine all the aircraft. The most intense area of the fire occurred in the lower half of the wreckage trail. The upper portions of the wreckage trail were also subjected to the post-crash fire but to a lesser extent.
“Airport Crash Fire Fighting Rescue (CFR) vehicles arrived at the site approximately 10 minutes after the accident. Fire suppression activities commenced immediately using dry chemical and foam. Additional fire vehicles and personnel were dispatched from the town of Gander. With the exception of a few stubborn spot fires the fire was extinguished within 45 minutes of the arrival of rescue vehicles. These spot fires were extinguished within four hours, except for one which continued to burn for 23 hours.
“CFR personnel reported that there were a number of explosions seen and heard throughout the burning wreckage area. Some were strong enough to lift mounds of rubble several feet into the air….
“Several…other witnesses observed portions of the take-off roll and brief flight which followed. None described observations consistent with a glow or fire. One of these witnesses was the air traffic controller on duty in the control tower. He observed the take-off of the aircraft until it descended below trees beyond the departure end of the runway. He did not observe any sign of fire or glow other than appropriate aircraft lighting. A second witness observed the take-off of the aircraft from a vantage point on the airport ramp, south of the main terminal building. He also observed the take-off until the aircraft descended below trees beyond the departure end of the runway and reported seeing no fir or anything else unusual other than the aircraft’s failure to continue to climb….
“Analysis. Analysis of all available information from the FDR, witness observations, and radar data indicates that, following an apparently normal ground roll, the aircraft failed to achieve a normal rate of climb. Within a few seconds of rotation, the airspeed began to decrease, and, at an altitude of no more than 125 feet above the runway, the aircraft stalled. A rapid descent ensued, and, about 20 seconds after lift-off, the aircraft struck trees on downsloping terrain about 2,900 feet beyond the departure end of the runway. Aircraft pitch attitude and the flight path angle at impact were indicative of an angle of attack of 21 degrees, well beyond the normal stall angle of attack….
“There was considerable speculation that the accident occurred as a result of the detonation, either accidental or through sabotage, of some explosive device. This speculation was fuelled by the fact that military personnel and equipment were aboard the flight and by the increasing worldwide incidence of terrorist activity. Also contributing to this speculation were a reported claim of responsibility by a terrorist group, the point of origin of the flight, and the reports by three witnesses of a yellow/orange glow emanating from the lower surface of the aircraft. The observations of the yellow/orange glow also raised the possibility of a pre-impact fire.
“Detailed examination of the wreckage with the assistance of forensic experts of the RCMP, including examinations at the RCMP Central Forensic Laboratory, revealed no evidence of an explosion or pre-impact fire. All damage to the aircraft and its components was considered to be the result of impact with terrain and the post-crash fire.
“The Board believes there is sufficient evidence to conclude that two side panels were missing in the number three cargo pit. The absence of these panels would compromise the integrity of the Class D classification of this compartment. A Class D cargo or baggage compartment is one in which: a fire occurring in it will be completely confined without endangering the safety of the airplane or occupants; there are means to exclude hazardous quantities of smoke, flames, or other noxious gases from any compartment occupied by the crew or passengers; and ventilation and drafts are controlled within each compartment so that any fire likely to occur in the compartment will not progress beyond safe limits. Thus, although the Board found no evidence to suggest that a fire had occurred in the number three cargo pit, the missing side panels would permit ventilation of the compartment and. in turn, possible propagation of a fire, if one had originated in this compartment.
“Examination of the engine fire extinguishing agent containers indicated that it was possible that agent had been released into the number three engine as a result of crew actions; the explosive charge had fired while agent was still in the container. This and witness observations of the yellow-orange glow raised the possibility of a pre-impact fire in the number three engine. However, other evidence indicates that this did not occur. Intentional discharge of the fire extinguishing agent into an engine through operation of the fire extinguishing agent discharge switches first requires movement of the appropriate engine fire shut-off lever. One of the functions of this lever is to close the fuel shut-off valve, thereby shutting down the engine. The number three engine was determined to be operating and at high rpm at ground impact. This indicates that the engine had not been shut down prior to ground impact The evidence also indicates that the Master Fire Warning light was not illuminated at impact. Activation of the fire extinguisher would also be contrary to Arrow Air published emergency procedures and training which specify that, in the event of an emergency during take-off, flight crews are to wait until a safe altitude (1,000 feet AFE) is attained before dealing with specific problems.
“Discussions with the manufacturer of the fire extinguishing agent containers indicated that it is possible for the explosive cartridge in the container to activate as a result of exposure to the high temperatures associated with a post-crash fire or through energizing of the actuating circuit during aircraft breakup. In consideration of all of the available evidence, the Board concludes that the discharge of the fire extinguishing agent was the result of either impact or the post-crash fire and not the result of an intentional action on the part of the flight crew.
“Despite an extensive search of the area between the departure end of the runway and the initial impact point, no components or debris was found that originated from the aircraft evidence that the aircraft was intact until initial impact with the terrain.
“There was no evidence found of any ammunition or military ordnance in the wreckage. A thorough inspection of personal baggage loaded on board the aircraft had been carried out prior to departure from Cairo. No explosive materials or otherwise hazardous items were discovered. The Board noted no significant difference between the weapons recovered and those reported to have been on board.
“Several small post-impact explosions occurred in the burning wreckage. Although some of these explosions were reportedly large enough to cause mounds of rubble to lift several feet into the air, none were considered of sufficient magnitude to be the result of detonation of explosive devices. The Board attributes these explosions to the normal bursting of pressure vessels (accumulators, fire extinguishers, aerosol cans, etc.) due to the heat of the fire. It is also likely that some of the reported explosions may have been firing of up to ten .45 caliber small arms rounds reported to have been carried on the aircraft by the Battalion Commander and the CID inspector.
“The occurrence of a pre-impact fire or explosion was also not supported by the autopsy evidence and the blood carboxyhemoglobin levels of the aircraft occupants.
“No evidence was found of shrapnel wounds and/or the identifiable portions of an explosive device, nor were injury patterns deemed to be characteristic of a pre-impact explosion.
“All of the pathologists involved in the assessment of the pathological/toxicological evidence agreed that pathological examinations and toxicological analyses yielded no evidence of pre-impact inhalation of the products of combustion and that, when these findings were combined with evidence from the accident site, injury patterns and mechanisms and timings of death, pre-impact inhalation of products of combustion could be excluded beyond any reasonable doubt.
“Although there was some level of HCN detected in the remains of the majority of aircraft occupants, it was the conclusion of all pathologists involved in the assessment of the pathological and toxicological findings that the HCN values were unreliable as an indicator of pre-impact fire and, at best, only indicative of exposure to fire. A high correlation with exposed chest cavities and hemothorax was noted in the cases with very high HCN concentration. In the 20 cases with the highest HCN concentration, 17 cases had exposed chest cavities and 16 had either documented hemothorax or multiple rib fractures which was accepted as evidence of hemothorax. This represented a highly significant correlation between high HCN levels and hemothorax. Almost all the blood samples were retrieved from the body cavities, and, thus, it was the agreement of all pathologists involved that much of the HCN in the blood was the result of post-mortem exposure to fire. The effects of neo-formation on the HCN levels, if any, could not be identified.
“CO values were considered to be a reliable indicator of the inhalation of the products of combustion. In this regard, all cases of elevated CO levels were considered to be the result of postimpact inhalation of the products of combustion.
“In summary, it was concluded that all aircraft occupants died as a direct result of impact and/or the post-crash fire. Some of the victims sustained injuries compatible with short-term survival and died as a result of inhalation of the products of combustion, either primarily or in combination with severe injuries sustained during impact. No evidence of any pre-impact fire or explosion was found as a result of the pathological examinations and toxicological testing.
“Finally, the performance of the aircraft was not consistent with a sudden and catastrophic event such as an explosion.
“Considerable interest was generated by the yellow/orange glow reported by some witnesses. However, in the absence of corroborating physical evidence, the Board was unable to determine the source of the illumination described by these witnesses. In assessing the significance of this evidence, the Board took into account that each saw the aircraft for only a brief period of time, and, since all were driving vehicles when they made their observations, they could not fully direct their attention to the aircraft. As a result, none was able to precisely describe the phenomenon, nor fix its position on the aircraft. Although at least one of these witnesses thought that the glow might have been a fire, he was not certain. Experience has shown that, when an accident is followed by a post-impact fire. witnesses often tend to associate fire with pre-impact observations.
“The Board also noted that other witnesses who observed the aircraft during its brief flight did not report observing this glow or any other observation consistent with a fire. Two of these witnesses observed the take-off of the aircraft until after it began to descend below trees beyond the departure end of the runway.
“It is possible that the glow observed by some witnesses was the illumination from normal light sources on the aircraft such as landing lights. One of these witnesses attributed the phenomenon to the reflection, on the bottom of the aircraft, of approach lights for runway 04 located on the extended centre line of runway 22. It could not be determined if the approach lights to runway 04 were illuminated at the time of the accident. It is also possible that the phenomenon observed by these witnesses was caused by compressor surging of one or more engines, resulting from disruptions in intake airflow. Compressor surges accompanied by flame emanating from the engine have been observed in other DC-8 accidents where angles of attack at or beyond the stall were achieved….
Findings
- During the approach to land at Gander, the existing meteorological conditions were conductive to ice accretion on the leading edge of the wing.
- While on the ground at Gander, the aircraft was exposed to freezing and frozen precipitation capable of producing roughening on the wing upper surface.
- While the aircraft was on the ground at Gander, the difference between the wing surface temperature and the outside temperature was conducive to the formation of frost on the surface of the wing.
- The aircraft was not de-iced prior to take-off.
- The aircraft stalled at a higher than normal airspeed after leaving ground effect.
- There was insufficient altitude available to effect a recovery from the stall.
- The performance of the aircraft after lift-off was below that expected and was consistent with the reduced aerodynamic efficiency and resultant high drag associated with wing ice contamination. It was also consistent with the effects of wing ice contamination combined with a partial loss in engine thrust.
- The ground impact rpm of the number four engine was lower than that of the other three engines.
- No evidence was found of a pre-impact mechanical failure of the number four engine.
- It could not be determined if the lower ground impact rpm of the number four engine was the result of an in-flight power loss, either before or after the stall, or was the result of tree fragment ingestion prior to ground impact.
- The integrity of a Class D cargo compartment was compromised because flight was undertaken with two missing side panels in the number three cargo pit.
- The take-off weight at Gander calculated by the crew was about 14,000 pounds less than the actual take-off weight of the aircraft.
- The take-off reference speeds believed to have been used by the crew during the accident take-off were applicable to a take-off weight at least 14,000 pounds less than the actual takeoff weight and may have been applicable to a take-off weight as much as 35,000 pounds less than the actual take-off weight.
- Although the use of actual passenger weights was required by the Arrow Air Operations Manual, the crew used a standard average weight to calculate the weight of passengers. This average passenger weight did not accurately reflect the actual weight of the passengers carried on the flight.
- Guidance material available to Arrow Air flight crew did not include direction concerning the requirement or method to determine total passenger weight using actual passenger weights when calculating weight and centre of gravity.
- Accurate weight and centre of gravity calculations were not being performed by Arrow Air flight crew for every flight.
- Inconsistencies existed in the load-planning material that was available to Arrow Air personnel, MFO personnel, and U.S. Army personnel.
- The quantity and accuracy of documentation regarding the number and weight of passengers and weight of cargo carried on the MFO rotation flights were inadequate.
- The maximum design zero fuel weight of the aircraft was exceeded on each of the MFO rotation flights conducted in December 1985.
- Arrow Air’s contractual obligations with respect to allowable payload exceeded the authorized payload capability (maximum design zero fuel weight) of the aircraft being used.
- Arrow Air flight crews were not recording all aircraft unserviceabilities in the aircraft journey log and on occasion were accepting for flight aircraft with known defects.
- A life-limited repair resulting from a previous occurrence had not been replaced in accordance with the recommendations of the aircraft manufacturer.
- The potential of the flight crew’s December flight schedule to produce fatigue was high.
- There are no flight-time and crew-rest limitations for United States FAR Part 121 air carrier operations conducted under FAR Part 91.
- The accident investigation into the causes and factors that led to this occurrence was severely hampered by the lack of information that a serviceable cockpit voice recorder and enhanced-capability digital flight data recorder could have provided.
- The United States Federal Aviation Administration Master Minimum Equipment List for aircraft such as the DC-8 allowed aircraft to be released for flight with an unserviceable cockpit voice recorder and flight data recorder.
- Routine FAA surveillance of Arrow Air did not identify existing deficiencies with respect to Arrow Air’s ability to comply with applicable FARs and FAA approved procedures. These deficiencies were identified in a special inspection conducted in January 1986, one month after the accident.
- The balance of evidence did not support the occurrence of a pre-impact fire or explosion either accidental or as a result of sabotage.
- The evidence did not support the occurrence of an uncommanded deployment of a thrust reverser.
- The flight crew was certified and qualified for the flight in accordance with existing regulations.
- The aircraft was certified in accordance with existing regulations.
- The take-off weight and centre of gravity position were within prescribed limits.
“Causes The Canadian Aviation Safety Board was unable to determine the exact sequence of events which led to this accident. The Board believes, however, that the weight of evidence supports the conclusion that, shortly after lift-off, the aircraft experienced an increase in drag and reduction in lift which resulted in a stall at low altitude from which recovery was not possible. The most probable cause of the stall was determined to be ice contamination on the leading edge and upper surface of the wing. Other possible fact…such as a loss of thrust from the number four engine and inappropriate take-off reference speeds may have compounded the effects of the contamination.” (Canadian Aviation Safety Board. Aviation Occurrence Report. Arrow Air Inc.)
CASB Dissenting Opinion: “Introduction/Summary. In our judgement, the wings of the Arrow Air DC-8 were not contaminated by ice – certainly not enough for ice contamination to be a factor in this accident. The aircraft’s trajectory and performance differed markedly from that which could plausibly result from ice contamination. The aircraft did not stall. Accordingly, we cannot agree – indeed, we categorically disagree – with the majority findings.
“The available evidence convincingly shows that the right outboard engine was producing little power before it contacted trees. The investigation of the other engines was inconclusive with regard to pre-impact status. We believe it possible that these engines were also operating at reduced power. All four thrust reversers may have been deployed.
“The evidence shows that the Arrow Air DC-8 suffered an on-board fire and a massive loss of power before it crashed. But, we could not establish a direct link between the fire and the loss of power. The line may have been associated with an in-flight detonation from an explosive or incendiary device. Consequential damage to various systems precipitated the crash.” (CASB Dissenting Opinion. Introduction/Summary. 11-14-1988.)
Sources
Canadian Aviation Safety Board. Aviation Occurrence Report. Arrow Air Inc. Douglas DC-8-63, N950JW, Gander International Airport, Newfoundland, 12 December 1985 (Report Number 85-H50902.) Accessed 1-23-2017 at: http://www.sandford.org/gandercrash/investigations/majority_report/html/_i.shtml
Canadian Aviation Safety Board. Arrow Air Inc….Dissenting Opinion. 11-14-1988. Accessed 1-23-2017 at: http://www.sandford.org/gandercrash/investigations/minority_report/html/_1.shtml
Planecrashinfo.com. “1985. Accident Details. Arrow Airways…Gander…Dec 12, 1985.” Accessed at: http://www.planecrashinfo.com/1985/1985-72.htm
