Experts in the nation’s aviation industry have called on regulators and operators in the industry to urgently conduct integrity checks on aircraft tyres following the recent near crashes involving two aircraft caused by burst tyres.
According to the experts, the aircraft operating in the country’s airspace were parked for several months during the COVID-19 induced lockdown, which could have compromised the integrity of their tyres.
Recall that 66 passengers and six crew members onboard escaped death last weekend as an aircraft in the fleet of Air Peace got its tyre bursted shortly after landing at the Ilorin International Airport.
This is even as another major accident was also averted in the month of February, in Lagos , when a Boeing 737 Azman Air flight, coming from Abuja landed and bursted one of its tyres at the 18L runway of the Murtala Mohammed International Airport (MMIA), Lagos.
Although, no casualty was recorded among the over 100 passengers on board the flight as they were quickly evacuated, the incident involved a Boeing 737-500 with registration number 5N-SYS, and flight number ZQ2325, named Sani Yunusa Sarina.
Speaking on the issue, a member of the Aviation Round Table, Olumide Ohunayo, blamed the recent worrisome development on prolonged parking during the nationwide lockdown occasioned by COVID-19.
Ohunayo explained that temperature, debris on the runway can also lead to burst of aircraft tyres, calling on regulators to urgently investigate the incidents.
Another cause of tyre failure, according to him is tyre retread, which he said had remained a source of worry in the industry. He added that it involves the remoulding or refurbishment of old aircraft tyres.
Tire retreading, also known as remold or recap, is the process of remanufacturing tires to replace the tread or rubber on worn tires,” according to market researchfuture.com.
Asked if retread tyres used by aircraft is not the same as fairly used tyres, Ohunayo said, “I don’t subscribe to the word fairly used tyres but what I think is that we have a period where aircraft were grounded for a long time and that might have contributed to the spate of tyre bursts.
“Again, it may be an issue of whether the runways are being cleaned regularly or not? Do they have debris on it? It requires investigation though it is an incident, but we shouldn’t allow the incidents to go without having investigation into what happened.”
He further stated that, “The long time the aircraft spends on ground, the runway or even the temperature at certain airports compared to the temperature in the tyres can contribute to the burst.
He advised regulators to investigate the reasons behind the increase in incidents caused by burst tyres.
According to him, “Fairly used tyres are not accepted in the industry and it’s not what we can toy with in the industry because everyone knows the cost of an accident.
“We shouldn’t get ourselves involved in that because commercial operators know the implication of an accident though, maybe private operators can do that but certainly not commercial operators.”
Meanwhile, a pilot who pleaded not to be named told LEADERSHHIP Sunday that Airplane tires rapidly go through temperature cycles (in-flight: -50 ºC, and on touchdown they rapidly heat up to several hundred ºC.
The aviation source further explained that airplane tyres are kept at much higher pressures, so if there’s a failure it’s more likely to be catastrophic. He stressed that aside carrying for running at high speeds (300 km/h and more), they also carry a lot of weight which explains why they need such high pressures.
The source further explained that It really isn’t that common in the big scheme of things, but there may be a factor that makes them more common than they might otherwise be. He said, “A lot of airlines retread their tires because they go through them so fast (try the life of a tire, going from 0 to 140 in half a second, then having to deal with producing extreme braking friction, 6 times a day, and see how long you last lol).
He said, “You can recap airline tires indefinitley as long as the basic carcass is within certain serviceability limits. An airline will send their worn tires to Goodyear or Michelin to have them basically remanufactured and they are theoretically as good as a new one, but in reality probably not quite (but good enough).
He said If an airline uses new tires all the time, they might expect to have fewer tire disintegrations, but the costs would be astronomical and I would say the majority of operators recap them until the carcass has to be scrapped.
However, according to TRIB, a United States of America-based tire retread and repair information bureau, “a retreaded tire generally sells for between 30 and 50 per cent less than comparable new tires.”
The bureau’s website additionally said, “retreaded tyres may actually have a few advantages over new tyre.”
But further checks by LEADERSHIP Sunday showed that retread tyres continue to cause air crashes despite the clean bill operators give the practice.
In its aviation safety investigations and reports, following the failure of the landing gear tyre of a Boeing B737-86N aircraft VH-VOH, the Australian Transport Safety Bureau, said: “On December 19, 2004, a Boeing Company 737-86N aircraft, registered VH-VOH, was being operated on a scheduled passenger flight from Melbourne, Victoria to Canberra, ACT.”
The bureau added: “At about 1655 Eastern Daylight-saving Time, while landing on runway 35, the right inboard main landing gear tyre failed.
“In December 2004, the Australian Transport Safety Bureau (ATSB) noted an increase in the rate of tyre failures on Boeing 737 aircraft in Australia.
“It was noted that all of the failed tyres were at retread level (the number of times it had been retreaded) 4 and 5. The ATSB investigated the VH-VOH tyre failure in conjunction with these other recent failures.
“Examination by the ATSB and the tyre manufacturer found that all the tyres had failed due to fatigue in the sidewall. That fatigue was a result of cyclic flexing of the sidewall and was possibly present to some degree, but not detected, at the last retread.
He said,“Aircraft tyres of this type had several operational measures to prevent premature failure. Those included non-destructive inspection during the retread process, inflation pressure maintenance, and aircraft weight and speed limitations.
“The ATSB found that changes could be made by the aircraft operator and retread facility to improve the pressure maintenance and inspections during retread.
“As a result of this investigation, safety improvements have been made by the aircraft manufacturer, aircraft operator and tyre retread facility to improve the life and reliability of the retreaded tyres.He concluded.”
The United States Federal Aviation Administration is reviewing the certification requirements for the tyres and retread packages to include improved reliability programmes.”
Speaking to LEADERSHIP Sunday on the issue, chief executive officer, 7Star Global Hangar, Isaac Balami, said there is nothing like fairly used tyres in the aviation sector but retreaded tyres.
According to him, retreaded tyres are prevalent and globally accepted as foreign airlines also retread their tyres.
He said, “I don’t think the issue of fairly used tyres is the reason we are having tyre bursts. They are not fairly used tyres but rather retreaded tyres.
“Retreaded tyre is when a tyre is used to a particular layer, you put more canvass on it and manufacturers authorise it even in the United States of America.”
He stated further, “British Airways, Lufthansa everyone uses it. So, that’s not the issue but, so many other factors can cause aircraft tyre burst which I believe should be left for the Accident Investigation Bureau (AIB) and the Nigerian Civil Aviation Authority (NCAA), to verify.
On his part, the chief operating officer, Tropical Arctic Logistics Limited, Engr. Femi Adeniji demised the use of fairly used tyres by any airline operator due to its consequences.
Adeniji said insisted that the ugly incident may not be unconnected with the fact that affected aircrafts have been idle for a long time.
He said, “No operator will make use of fairly used tyres in the aviation industry. But, most of these airlines sat down for too long on a spot and by maintenance practice, they are supposed to be rotated and if not, change the tyres. Cutting corners might come in but, I won’t say it’s cutting corners but rather, not following the regular maintenance procedures,” he stressed.
The general manager, Nigerian Civil Aviation Authority (NCAA), Sam Adurogboye, said aircraft in the nation’s airspace are checked regularly.
“NCAA inspectors are at the various Airports conducting regular checks on them. Planes are not parked in hidden places. Maintenance too, is not done in a place not known to us.”