A History of BAC-111 Aircraft Accidents

The British Aircraft Corporation BAC-111, of which 233 were produced between 1963 and 1982 in the UK, was a low-capacity, short-range twin-jet in the Sud-Aviation SE.210 Caravelle, Tupolev Tu-134, and McDonnell-Douglas DC-9 class, powered by two aft fuselage-mounted Rolls Royce RB. 163 Spey turbofans. It was built with two fuselage lengths-the 89-passenger, short-body BAC-111-200, -300, -400, and -475, and the 119-passenger long-body BAC-111-500. Nine of the later, designated Rombac 1-11-560s, were also license-manufactured in Romania.

This study looks at the type's accident history.

During the 14-year period from 1965, when the twin-jet first entered scheduled service, to 1978, there were ten fatality-producing accidents resulting in 246 deaths, although two of these only involved a single death each. Six years were entirely accident-free: 1965, 1968, 1972, 1974, 1976, and 1978.

An important, but nonfatal incident that would echo a KLM DC-8 one as it made its approach to Tokyo on April 7, 1966, occurred two months earlier, on February 25, when the captain of a Braniff International Airways BAC-111-200 with 54 passengers on board touched down at Chicago-O'Hare and abruptly turned to the first officer, yelling, "You've got it!

The first officer, failing to understand the sudden changeover, watched the captain as he collapsed with a heart attack in the left seat and requested that an ambulance be available at the arrival gate. But as the aircraft moved into position there, the captain had already succumbed to death and was so pronounced after his rush to the hospital. The incident remains one of only a handful in which the pilot-in-command died as a result of natural causes while flying an airplane.

The first fatality-resulting BAC-111 accident, which took place later that year on August 6, was, perhaps, the most important one, because it questioned the reliability of t-tailed designs, as such shedding suspected light on other, similarly configured aircraft, including the Caravelle, the DC-9, and the Fokker F.28 Fellowship.

In command of Braniff International Flight 250, a BAC-111-200 operating a multi-sector service from New Orleans to Minneapolis, with intermediate stops in Shreveport, Fort Smith, Tulsa, Kansas City, and Omaha, was Captain Donald G. Pauly, 47, who had logged more than 20,000 hours and 549 of them in type in the past 14 months, and First Officer James A. Hilliker, 39, who himself had logged 685 hours in the British twin-jet. Two flight attendants served the 37 passengers in the cabin.

The first four legs proceeded routinely. But prior to its departure from Kansas City Municipal Airport, it faced significant enroute weather, with the National Weather Bureau predicting severe thunderstorms as high as 50,000 feet.

Taking off at 2250, the Braniff aircraft was instructed to climb and maintain 5,000 feet before being further cleared to 20,000 feet. So severe was the solid line of thunderstorm activity, as indicated by its cockpit weather radar, however, that the captain requested clearance to re-descend from his present 6,000 feet to 5,000.

Realizing that a solid line of such thunderstorms now lay ahead as far as Des Moines, he initially considered diverting, but subsequently only requested a course deviation so that he could navigate through the holes in the clouds, as indicated by his cockpit instrumentation.

Yet, at 2311, without choice, the BAC-111 was forced to penetrate the storm, doing so at the 270-knot recommended turbulence penetration speed. It was now five miles from the line of thunderstorm cells, where the greatest amount of turbulence would be generated.

Seventeen seconds later, four cockpit stall warning alarms sounded and, at 2311:28, the twin-jet, wrenched by a severe updraft, lost its vertical fin and right horizontal stabilizer, disappearing from the radar scope. Gravity-induced into an earthward plunge, it dove.

Reduced to nothing stronger than balsa wood in the midst of the force, the starboard wing was separated from the fuselage, leaving the remaining structure to conflagrate as a result of the 9,000 gallons of now spilling fuel.

Diving at a near-vertical angle, the flaming, dismembered BAC-111 barreled out of low-altitude clouds and torpedoed into a muddy soybean field 7.5 miles northeast of Falls City, Nebraska, only 15 minutes short of what would have been a touchdown at Omaha's Eppley Field, exploding a second time and instantaneously killing all on board. The wing came to rest a half mile from the impact site and the tail 2,752 feet further than that.

The ensuing investigation focused on four aspects: the weather, the discrepancy in its predication by that of the National Weather Bureau and Braniff's own meteorological department, the captain's decision to take off based upon both, and the aircraft's structural integrity.

Although the cockpit voice recorder had ceased functioning at 2311:28 when the aircraft had disappeared from the radar scope, the throttles indicated that they had been at the turbulence penetration speed setting. It was also evident that the captain had been unable to determine the presence of squall lines as he bored through the cloud breaks, since this phenomenon was not measurable by his existing cockpit instrumentation. Experience had demonstrated that it usually occurred several miles ahead of a thunderstorm and was associated with ground-originating and -rising winds that collided with those that descended from thunderstorm cells, creating wind shear. The National Weather Bureau detected this on the aircraft's flight path.

The BAC-111's t-tail configuration and the type's structural ability to withstand such a phenomenon came sharply into focus. While the aircraft had been rigorously flight-tested before certification and had demonstrated its reliability during US carrier operation with Mohawk and Braniff, it was important to determine if such a tail assembly had been more vulnerable to wind forces than conventional ones were.

Toward this end, the British Aircraft Corporation, the Department of Transportation Safety Board, and NASA conducted exhaustive tests, including those in wind tunnels, leaving the FAA to issue a report, which in part read, "It is concluded that the BAC-111 is constructed and has been tested with the latest state-of-the-art. The testing of structure, loads, and fatigue have been very intense and beyond the normal requirements. Environmental testing, with its exception of icing testing, has been more extensive than those required by like United States aircraft. It is believed that adequate corrective and preventive action has been taken in the design and systems to preclude similar problems as occurred during the developmental accident" (with reference made to the installation of the type's automatic stick pusher and stall prevention system).

With the design thus exonerated, it was determined that the aircraft had been subjected to wind shear too excessive for its design limits at a time when cockpit instrumentation was insufficiently advanced to detect the phenomenon.

The National Transportation Safety Board, however, criticized both the National Weather Bureau's and Braniff International's differing weather predictions, determining that the latter's had been incorrect and inadequate. Toward this end, it stated that Flight 250 had flown into "an area of avoidable hazardous weather," referring to the 30-mile-long squall line in its flight path. It concluded by stating that "… the intensity of the weather system which crossed the intended route appears to have been underrated by airline personnel responsible for forecasting the weather and dispatching the aircraft."

Nevertheless, the accident disclosed a significant amount of information concerning weather, turbulence, and wind shear affects on current pure-jet airliners.

The second BAC-111 accident, which occurred on June 23, 1967, differed from the Braniff incident, but nevertheless re-questioned the integrity of the British design.

Piloted by Captain Charles Bullock and First Officer Troy Bungert, Mohawk Airlines Flight 40, another BAC-111-200, was executing a tri-sector flight from Utica to Washington with intermediate stops in Syracuse and Elmira with 30 passengers and two flight attendants aboard.

Rotating at 1439:40 from Runway 24 at Elmira, now 29 minutes behind schedule, the aircraft was given clearance to climb and maintain 16,000 feet at the start of its instrument flight rules (IFR) flight plan to Washington-National Airport. Storm clouds, littering the sky, made it impossible for the cockpit crew to determine their attitude in relation to the ground, as evidenced by the captain's comment, which was "I can't see a thing out there, Troy."

So difficult did control become as the aircraft penetrated the dark storm cell, that it could not comply with New York Center's clearance to climb to 16,000 feet. Cockpit conversation confirmed this.

"Ah, feel… it's not doing that exactly… It's hard to tell just what it is," commented the first officer at 1444:33.

"Ah, let's see," replied the captain. "Pull back on your speed."

"Wait a minute," the first officer countered. "I'm doing it. Hey, there's something screwy here."

That some malfunction had occurred was obvious. That the crew was not aware of what it was, was equally apparent by the last statement. But whatever the cause was, the twin-jet was unable to climb to its assigned altitude and requested clearance to return to Elmira, a remedy which, in the event, quickly proved unachievable.

At 1445:16, the captain reported to the first officer, "We lost all control! We don't have anything!"

Despite a manual control attempt, it failed to respond, as evidenced by the captain's statement, "Yeah, but I can't do anything."

After a brief period of attempted reclimb, he said, "Pull back! Pull back! Keep workin'. We're making it. Pull back straight now. Climb now. That's it. Easy now. Now, cut the gun, cut the gun. We're in now."

The resultant erratic maneuver, which appeared as a suddenly moving blip on the radar screen, was emphasized by the first officer's comment, which could have referenced an unexpected roller coaster ride.

"Oooh-weee! I don't like that," he said.

Recognition that something was amiss with the tailplane came at 1446:37 when the captain asked, "What have we done to that damn tail surface. Ya have any idea?"

The first officer did not. Nevertheless, a last-ditch effort was made at 1446:47 when the captain clutched the yoke with both hands.

"Both hands, back! Both hands!" he instructed. "Pull back!" But only 16 seconds later, he pronounced, "I've gone out of control."

The radar blip representing the flight disappeared from the scope. Exploding and encased in flame, the BAC-111 plunged earthward and plowed into a forest near Blossburg, Pennsylvania, cutting a 500-year-long swath as it sliced through birch and maple trees before exploding a second time. The tail was thrown 1,000 feet from the main wreckage, which itself had been reduced to flaming litter. It was 1447:17. All 34 on board died on impact, which had produced a 20-foot-wide by six-foot-deep hole in Barney's Hill 30 miles north of Elmira. It was the second accident in Mohawk's 21-year history.

Because of the crash site's inaccessibility, several coal miners, who had witnessed the impact, first had to clear two 1.5-mile paths with 31-ton bulldozers to it before it could be reached. Witnesses later reported that they had seen the tail and pieces of the left wing dislodge themselves from the main structure while the aircraft was still flying, claiming to have detected flame. These observations prompted Robert E. Peach, Mohawk's president, to send a telegram to J. Edgar Hoover of the FBI, stating, "Evidence has developed in the course of notification of next-of-kin of crash victims which leads to strong suggestion of sabotage. Mohawk Airlines formally demands that the FBI investigate the possibility of sabotage."

Although the ensuing investigation eventually disclosed inflight structural failure, its originally suspected, sabotage-related cause was discounted, because a bomb-created explosion would have left silver powder residue, none of which, despite an exhaustive search, was ever uncovered. Weather was also ruled out as the cause.

But eyewitness accounts of fire and structural failure led to the investigation's focus, revealing that an inflight fire in the aircraft's pitch control system had rendered the BAC-111 uncontrollable.

In a statement issued by the National Transportation Safety Board, Edward E. Slattery, Jr. said, "It has now been determined, both from structural examination and corroboration by witnesses on the ground, that the plane had a fire in the tail area during flight."

Turbulence proved the culprit of two deaths on a BAC-111 flight operated by LACSA of Costa Rica enroute to Miami with an intermediate stop in Grand Cayman on October 9, 1967. Piloted by Captain George Paris, the aircraft, with 16 passengers, routinely cruised abreast of the Nicaraguan coast at 29,000 feet when a turbulent area was detected and the fasten seatbelt sign was illuminated.

Ten minutes later, the twin-jet encountered three downdrafts that were so severe, that they caused it to plunge 10,000 feet before recovering, during which time the cabin was reduced to chaos as all unfastened items torpedoed through it. Two passengers, Ricardo Castro Beeche, a San Jose newspaper publisher, and Claudio J. Loria, an American, both of whom had failed to fasten their seatbelts, were catapulted to the ceiling where they remained pinned until the g-forces had sufficiently subsided to permit them to re-fall to the cabin floor. But they had already succumbed to their injuries, while another six passengers sustained survivable ones.

Granted immediate landing clearance, the aircraft touched down in Grand Cayman where five of the six were treated and released. The remaining passenger, Beeche's daughter, sustained rib fractures.

Despite the excessive forces exerted on it, the aircraft itself suffered no damage, but remained grounded until it could be subjected to closer inspection. Two other LACSA airplanes were flown to Grand Cayman to either transport passengers to Miami or back to San Jose.

The incident demonstrated the undetectability and the severity of certain types of turbulence.

Forty-five passengers were killed two years later, on September 12, 1969, when a Philippine Airlines BAC-111 attempted to conduct an automatic direction finder (ADF) approach to Manila International Airport through cloud and fog when its power failed and the ADF signals could no longer be received.

Trying to determine his position, the captain radioed that he was at 3,000 feet, but, in reality, he was only 700 feet above the ground. The twin-jet impacted 15 miles east of Manila, exploding. Two of the 47 aboard were saved when they were ejected from the wreckage.

Another PAL BAC-111 accident took place the following year, on April 21, 1970, when a hand grenade-induced explosion ripped off the tail section while the aircraft cruised at its assigned altitude, causing it to hurdle to the ground 75 miles north of Manila in the province of Nueva Ecija. All 36 aboard were killed.

The cause was attributed to two theories: 1). A passenger had endeavored to commit suicide, or 2). Someone had been trying to kill Colonel Fileman Logman, a constabulary of the province of Isabela who was on board and who had been attempting to cease illegal logging and mining.

A Pan International BAC-111-500, piloted by Captain Reinhold Huls and conducting a charter flight from Fuhlsbuttel, Germany, to Malaga on September 6, 1971, was responsible for life loss after the captain detected an engine malfunction and made an emergency landing on the Kiel-Hamburg autobahn. Although the touchdown was smooth, the aircraft's wing hit a bridge and ruptured the fuel tank, which caused kerosene to spew out and feed the ensuing fire. Trapped and succumbing to smoke inhalation, 22 of the 120 on board perished.

1972, 1973, and 1974 passed before another BAC-111 fatality occurred. On June 3, 1975, a Philippine Airlines flight destined for Manila was subjected to an infight bomb detonation at 20,000 feet, resulting, miraculously, in the death of only a single who was blasted out of the aft lavatory, but the injury of 45 others. Despite its incapacitation and explosive decompression, the aircraft was able to execute an emergency landing.

Two years later, on November 21, 1977, an Austral BAC-111, registered LV-JGY and carrying 74 passengers and five crew members, crashed at the end of its 1,000-mile sector between Buenos Aires and San Carolos de Bariloche. Departing its origin at night, it encountered strong winds and subzero temperatures, but shortly before it was scheduled to arrive, it slid off the radar scope.

The wreckage, located 20 miles from its destination, was discovered the following morning. Forty-five of the 79 on board had perished.

The cause, the result of an improper and premature descent, which was below safety limits, was traced to a procedural error by the crew during the final approach. Abandoning the prescribed ILS procedure, which was the result of VOR signal interruption, the twin-jet failed to clear ground obstacles.

The final BAC-111 crash occurred in August of 1978 when a bomb exploded in a lavatory of a Philippine Airlines example operating a domestic flight between Cebu City and Manila at 24,000 feet with six crew members and 78 passengers on board. Although three were injured during the dive to 12,000 feet, the aircraft made a successful landing at its intended destination. Only after it had was it discovered that a passenger had been sucked out during the rapid decompression.


Source by Robert Waldvogel

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