Two men were responsible for a plane crash.

Nigeria Airways Flight 2120  was a chartered passenger flight from Jeddah, Saudi Arabia, to Sokoto, Nigeria on  July 11, 1991 which crashed shortly after takeoff from the King Abdulaziz International Airport, killing all 247 passengers and 14 crew members on board. The aircraft was a Douglas DC-8 operated by Nationair for Nigeria Airways. Flight 2120 is so far the deadliest accident involving a DC-8 and also remains the deadliest aviation disaster involving a Canadian owned airline.                                                        

The aircraft  was owned by the Canadian company Nolisair, and was usually operated by Nationair and  at the time of the accident, it was being leased to Nigeria Airways, which in turn sub-leased it to another company to transport Nigerian pilgrims to and from Mecca Saudi Arabia.

William Allan, the 47-year-old pilot in command was a former Canadian Air Force pilot and he had logged 10,700 flight hours and 1000 hours in DC8s. Kent Davidge, the 36-year-old first officer, had logged 8,000 flight hours, of which 550 hours  in the same kind of planes and the 46-year-old flight engineer  had logged 7,500 flight hours, of which 1000 hours were in DC-8s that was the primary aircraft type used by the airline.

When the aircraft was leaving the runway of the Jeddah International Airport bound for  Sokoto, problems were reported shortly after takeoff. There was something wrong with the hydraulics.  The hydraulic system is what makes moving the various parts of the wings easier.  

The crew attempted to return to the airport for an emergency landing, since the aircraft was also on fire. When the aircraft was about 18 kilometres (11 miles) from the airport and at an altitude of 671 metres (2,201 ft), a number of bodies fell from it, indicating that the fire by that time had consumed, at least partially, the cabin floor. As it neared the runway, it crashed in flames 2,875 metres (9,432 ft) short of runway 34L. All 261 occupants of the plane perished in the accident.

The cause of the accident

Prior to departure, the lead mechanic had noticed that the #2 and #4 tire pressures were below the minimum for flight.   He attempted to inflate them but no nitrogen gas was readily available and the project manager, unwilling to accept a delay, disregarded the problem and readied the aircraft for its forthcoming flight.  

As the aircraft was taxiing on the runway, the transfer of the load from the under-inflated No. 2 tire to the No. 1 tire on the same portside axle resulted in over deflection, over-heating and structural weakening of the No. 1 tire. The No. 1 tire failed very early on the take-off followed almost immediately by the No. 2. The latter stopped rotating for reasons not established and the subsequent friction of the wheel assembly scraping along the runway generated sufficient heat to start a self-sustaining fire in the wheel assembly which would then expand by the speeding air hitting it.

The crew realized there was a problem, but not the nature or seriousness of it. The aircraft was not equipped with fire or heat sensors in the wheel assembly. The first officer was recorded as having remarked, "We gotta flat tire.”

 According to Canadian Transportation Safety Board members interviewed for an episode of the TV show, Mayday  about the accident, said that standard procedures regarding tire failure during the takeoff of the DC-8, is to stop the plane. However in this incident, the captain did not then stop the takeoff for the tire or wheel failures and instead, he proceeded with the takeoff. By the time he was aware of the danger below him, it might have been too late for him to stop the plane while he was still on the runway.                          

When the landing gear was retracted, the burning rubber was brought into close proximity with hydraulic and electrical system components", causing the failure of both hydraulic and pressurization systems that led to structural damage and subsequently the loss of control of the aircraft.

 The Transportation Safety Board later concluded and correctly, that had the captain left the landing gear extended, the accident might have been averted since the flames wouldn’t have reached the vital systems above the burning tires.  

As a result of fire in the wheel assembly, the flames reached the centre fuel tank which then intensified the fire, which in turn eventually consumed the cabin floor. People began falling out of the aircraft when their seat harnesses burned through. "Despite the considerable destruction to the airframe, the aircraft appeared to have been controllable until just before the fiery crash.     

Aftermath

Soon after the accident, a group of Toronto-based Nationair flight attendants pooled funds to create a memorial plaque, inscribed with the names of the victims. The memorial, complete with a cherry tree planted to commemorate their colleagues who died in Jeddah, was given a permanent home at the head office of the Greater Toronto Airports Authority

The air crash, combined with Nationair's poor reputation for on-time service and mechanical problems, led to serious problems with public image and reliability among tour operators. These difficulties were compounded when Nationair locked out its unionised flight attendants and proceeded to replace them with strike breakers on November 19, 1991. The lock-out lasted 15 months and by the time it ended in early 1993, Nationair found itself in severe financial trouble. At the time, Nationair owed the Canadian government millions of dollars in unpaid landing fees.  Creditors began seizing aircraft and demanded cash up front for services. The company was declared bankrupt in May 1993, owing CDN$75 million.

In 1997, Robert Obadia, owner of Nationair and its parent company Nolisair, pleaded guilty to eight counts of fraud in relation to the company's activities. Obadia had paid himself lavish dividends and salary, and taken low interest loans from the company. Obadia was ordered by a Quebec court in 1993 to repay investors and creditors $234,000. Obadia never served any time in prison despite pleading to 8 counts of fraud.

Controversy also surrounded Nationair with reports and allegations of sub-standard safety practices. Media reports revealed that the carrier regularly flew aircraft that were not airworthy. This controversy was further exacerbated by media reports that Transport Canada was aware of these practices but did nothing about it. The Canadian federal government declared after an investigation, in 1998, that there were deficiencies in a number of operational and management areas at Nationair, especially in maintenance work. Twenty years after the Nationair aviation disaster, further reports of sub-standard aircraft maintenance emerged with Lina Colacci (whose 23-year-old sister Dolores Colacci, a flight attendant, died in the disaster) stating in a CTV News interview in July 2011 that her sister "had kept a journal, and she had written how she was scared that the safety of Nationair was lacking." In the same 2011  CTV News interview Lina Colacci recounted her deceased sister's journal entries that described Nationair's "staff implementing makeshift repairs, such as plugging up holes in the bathroom with rags"

Some of the surviving family members launched a wrongful death class-action lawsuit against Obadia's Nationair. But their efforts were fruitless in recouping any damages as Obadia declared his company bankrupt in 1993, leaving the surviving families with no legal recourse.

As to who were responsible for the deaths, it was the project manager who permitted the plane to fly with an under-flated tire and the captain who raised the wheel assembly were the two men who caused the plane to crash and kill everyone on board.

This particular incident with respect to landing gears was not the first of its kind.

Swissair Flight SR306, a Sud Aviation SE-210 Caravelle III,  that was named  Schaffhausen, was a scheduled international flight  that was from Zürich to Rome, via Geneva. It crashed near Dürrenäsch, Aargau, on September 4, 1963, shortly after take-off, killing all 80 people on board.

The aircraft's brakes overheated due to the application of full engine power during taxiing along the runway. This caused the magnesium wheels to burst on the runway prior to lift off.  Upon retraction of the landing gear, the hydraulic lines in the gear bay were damaged. This was caused either by the wheels that had exploded, or the bursting of the other wheel rims during the climb. Subsequently, spilled hydraulic fluid ignited when it came in contact with the overheated landing gear rims. The fire damaged the gear bay, followed by the wing. Finally losing its hydraulic pressure, the aircraft became impossible to control. The cabin and the cockpit were filled with smoke, adding to the predicament of the crew. Control of the aircraft was lost totally at around 06:18, and the ensuing final dive and impact destroyed the aircraft.  As a result of this accident, all Caravelles were modified to use non-flammable hydraulic fluids.

Air France Flight 4590 was a scheduled international flight from Paris, France, to New York City, on the Aérospatiale-BAC Concorde. On  July 25, 2000, at time 16:43 CET, the aircraft serving the flight, registration F-BTSC, ran over debris on the runway during takeoff, blowing a tire and puncturing a fuel tank, leading to fire and engine failure. All 100 passengers and nine crew members aboard the Concorde died when it crashed into a hotel in nearby Gonesse. On the ground, four people were killed and one was critically injured.

These incidents are evidence that the fuel tanks have to be much harder to puncture and the hydraulic lines in the area of the wheel assemblies  have to be better protected. 

The fatal incident rate has declined steadily ever since  1997 when the the number of fatal air accidents has been no more than 1 for every 2,000,000,000 person-miles flown (e.g., 100 people flying a plane for 1,000 miles (1,600 km) counts as 100,000 person-miles, making it comparable with methods of transportation with different numbers of passengers, such as one person driving an automobile for 100,000 miles (160,000 km), which is also 100,000 person-miles), and thus one of the safest modes of transportation when measured by distance traveled.

However, people do make mistakes and that is why passenger planes on occasions do crash. I have travelled all over the world in passenger planes and I began to feel that the chances of me being in a plane crash were very, very unlikely.  That was a stupid conclusion. 

Several years ago, I was in a passenger plane in which the back end of the plane in which the engine was in place, hit the tarmac very hard during the plane’s landing. The engine caught fire so the pilot quickly taxied the plane to the terminal and ordered everyone to move quickly out of the plane. Alas because of a previous broken arm, I couldn’t reach the safety harness buckle to unbuckle it.  I was alone in the plane as the smoke and fire approached me. I was lucky that my wife was with me on that trip. She told the crew that I was still in the plane. A stewardess ran into the plane, unbuckled my safety harness and dragged me out of the plane to safety.