The impact of ageing aircraft on aviation safety

Each time there is a plane crash, what readily comes to mind is the issue of how old the ill-fated plane is. This has dominated discourse in Nigeria’s aviation industry for a long time with divergent opinions on what constitute old or geriatric airplanes.

In Nigeria, the age of aircraft became an issue following the crash of EAS in Gwarmaja, near Kano, on May 4, 2002, killing 64 passengers and seven crew members. In a bid to ‘prevent future occurrence,’ the Nigerian government decided to impose restrictions on the age of aircraft being registered in the country. The crash of Dana’s MD- 83, described as the worst accident in the history of plane crashes in Nigeria, brought to the fore again the issue of age.

This group equally linked other accidents to their ages. But reports of previous accidents did not in any way attribute the crashes to their age, but mainly to human error. It is on record that over 70 per cent of air crashes are caused by human error or human factor. Can Nigerian airlines acquire newer airplanes? The answer is no. Apart from Arik Air which bought newer airplanes about seven years ago, no other airline in Nigeria has accomplished that feat. Arik, expectedly, used that to gain a wider edge against its competitors to gain huge traffic as many Nigerians predicated safety on the operation of ‘tear- rubber’ aircraft.

The crash of Dana in 2012 shook the very foundation of aviation safety in Nigeria. Coupled with advertisement by Arik during that time that it operated ‘tear rubber’ planes raised the adrenalin of travellers and made other carriers to look like killers. It also made the NCAA to look as if it was incapable of regulating the aviation, safety wise. Globally, aircraft of over four years is no longer considered new. Mega carriers like Etihad, Emirates, Lufthansa, and some American and European carriers retire some of their long-haul planes every four or five years. Operating a younger fleet is not a guarantee to safe operations in itself, as other parameters are just as important.

The two Boeing VC-25As – specifically configured, highly customised Boeing 747-200B series aircraft, currently used as Air Force One by President Barrack Obama, were manufactured in 1990 (same year as Dana’s crashed MD83 aircraft). Crashes of new aircraft also occur. Examples vary from the Kenya Airways five-month Boeing 737 aircraft to Air France Airbus 330 that was 4.4 years and Japan Airways Boeing 747 that was 4.5 years old at point of loss. Simply put, a new aircraft that is badly maintained is more dangerous than a 20-year-old aircraft that has been well maintained.

Aircraft’s age is difficult to define. It is often referred to as simply the chronological age of aircraft. However, this excludes many important factors. In fact, aircraft age is a combination of the chronological age, the number of flight cycles and the number of flight hours. Determining an aircraft age is even made more complex by the fact that individual aircraft components will age at different rates. Chronolgical age is particularly relevant for corrosion, as the effects of corrosion increase over time. Flight cycles will cause fatigue in aircraft wings according to experts. The number of flight hours also cause fatigue and so is another important measure of an aircraft age.

President, Aviation Round Table (ART), Capt. Dele Ore, said the biggest issue with aging aircraft is that things do wear out. The repair and replacement of parts increase the cost of owning and operating the aircraft. He explained that a 20-year old aircraft has about 50-60 per cent higher maintenance costs than a new aircraft just out of warranty – excluding the engines, adding that these costs continue to climb two per cent to three per cent per year.

According to him, “older aircraft can be productive for many years. They do require more maintenance and at some point their cost and declining availability make them less useful to many. “When to replace an aircraft is not an easy formula. It does require monitoring and tracking of costs and availability, and a willingness to say goodbye to an old friend.” The biggest issue with aging aircraft is that the repair and replacement of parts increase the cost of owning and operating the aircraft. This hurts in two ways. One is the increased costs, which are obvious.

Speaking in the same vein, an aircraft engineer who preferred anonymity, said that the early years when the aircraft are young and warranties are in effect show very low maintenance costs – less than half of what they are at year five. “However, when the aircraft is 30 years old and wear and tear is taking its toll, the maintenance costs are typically more than double what they were at year five. As with any mechanical device, this makes sense.