Like every mechanical or electrical device fashioned and operated by human beings, the aeroplane can sometimes be susceptible to faults in the course of its operations.
Such faults could occur either while the aircraft is on ground, taxing for take-off or during landing, or while it has attained normal cruising altitude and heading for its final destination.
Often times, one notices passengers who remain restless throughout the course of a flight because of the fear of an imminent catastrophe on the aircraft. To such passengers, a change in the engine sound, a turbulence that shakes the aircraft, a sudden drop in altitude, and the decision to hold the aircraft for some minutes longer than the estimated arrival time, is enough to trigger in them the conviction of an imminent air crash.
However, it must be stated that unlike any other man-made machine, air travellers must bear in mind that the aeroplane is a specially built equipment that is made to operate and be maintained under very high and strict regulations such as is never seen in any other industry.
Aviation instructor, Musa Nehemiah describes the aircraft as an equipment that is built and operated under the best safety, security processes and procedural manuals that man can ever conceptualise.
Every aircraft that flies must carry a certificate of airworthiness from the Civil Aviation Authority (CAA) of the country of ownership or that which it operates validating its capability to engage in safe flight operation. The operational manual of the aircraft also clearly states when (even the minutest) component of the aeroplane should be serviced or replaced. The cockpit is a state-of-the art equipment (like a sophisticated car dashboard) that gives the two pilots manning the plane detailed idea of state of the aircraft once they ignites the engine.
The aeroplane therefore remains the safest mode of transportation on earth, says Nehemiah who teaches at the Nigerian College of Aviation Technology, Zaria.
Advancements in technology have outfitted modern planes with highly effective safety features that prevent catastrophic failures mid-flight. But no matter how fit the vessel, or how advanced the technology, there is one element that is impossible to control: the human element. People, even highly trained professionals, often make mistakes. Though major pilot error happens rarely, the results can be truly devastating.
“Whenever things go wrong, it usually has more to do with those who operate the aircraft, and little or nothing to do with the aircraft itself,” said Nehemiah.
It is therefore not surprising that in most of the accident investigations carried out on an aircraft, the root cause of such crashes is often traced to pilot errors.
Take the case of a pilot who took off from the Uyo airport to Lagos airport with a fuel tank cover that was not properly covered while refuelling. He switches on the engine, takes off and few minutes into the flight he notices a massive drop in the volume of his fuel and decides to abort the flight mid-way by force landing at an alternate airport in Port Harcourt. Investigators who rush down to ascertain what went wrong with the aircraft were shocked to note that the fuel cover was not properly shut thus leading to fuel leakages. In this instance, the error can only be attributed to the sheer negligence of the pilot who acted in a clear breach of the civil aviation regulations that requires that he goes round his aircraft and confirms that all openings are properly shut before flying the aircraft. The luck that the aircraft mentioned above enjoyed was that it was a local flight not one over flying a large expanse land or the Atlantic Ocean that offered him no alternate airport to land and fix the fault otherwise a crash was most inevitable.
Without doubt, when the fuel on board an aircraft is considered exhausted or insufficient to enable it land safely at its destination, it is a clear signal of imminent danger for the aircraft is bound to stall and crash like a log of wood or a heavy stone on the earth. The chances of survival of both crew and passengers on board such a flight is often decided by fate. And this is just one example of how a pilot error can lead to the crash of an aircraft.
Analyst, Simon Bennett, also lists four other most common reasons for airliner disasters
Equipment failures still account for around 20 per cent of aircraft losses, despite improvements in design and manufacturing quality. While engines are significantly more reliable today than they were half a century ago, they still occasionally suffer catastrophic failures.
In 1989, a disintegrating fan blade caused the number one (left-hand) engine of a Belfast-bound British Midland Boeing 737-400 aircraft to lose power. Hard-to-read instrumentation contributed to the pilots’ misreading of which engine was losing power.
Confused, the pilots shut off the number two (right-hand) engine. With no power, the aircraft crashed short of East Midlands Airport’s Runway 27, killing 47 and injuring many, including the Captain and his co-pilot.
Bad weather accounts for around 10 per cent of aircraft accidents. Despite a plethora of electronic aids like gyroscopic compasses, satellite navigation and weather data uplinks, aircraft still founder in storms, snow and fog.
One of the most notorious bad-weather incidents occurred in February 1958 when a British European Airways twin-engined passenger aircraft crashed while attempting to take off from Munich-Riem Airport. Many of the 23 killed on the aircraft played for Manchester United Football Club. Investigators established that the aircraft had been slowed to such a degree by slush (known to pilots as “runway contamination”), that it failed to achieve take-off speed. Surprisingly, perhaps, lightning is not the threat that many passengers believe (or fear) it to be.
About 10 per cent of aircraft losses are caused by sabotage. As with lightning strikes, the risk posed by sabotage is much less than many people seem to believe. Nevertheless, there have been numerous spectacular and shocking attacks by saboteurs.
Other forms of error
The remaining losses are attributed to other types of human error, like mistakes made by air traffic controllers, dispatchers, loaders, fuellers or maintenance engineers. Poor communication between air traffic controllers and pilots as well as sudden failure of navigational aids to guide pilots also can create problems. Sometimes required to work long shifts, maintenance engineers can make potentially catastrophic mistakes.
In 1990, a windscreen blowout on a British Airways flight nearly cost the life of the aircraft’s captain. According to the Air Accidents Investigation Branch, almost all of the windscreen’s 90 securing bolts “were of smaller than specified diameter”. Rather than attributing the mis-match between bolts and countersunk holes to his selection of the wrong-sized bolts, the maintenance engineer responsible for fitting the new windscreen blamed oversized countersinks. The engineer had not been sleeping well and did the windscreen replacement work during the period when his body clock wanted him to sleep, a time when reasoning and judgement easily falter.