AINsight: Reducing the Mx Burden Could Help Aviation

There is no doubt that there is a growing shortage of aircraft maintenance technicians (AMTs) worldwide, and it’s going to get worse. Not only are a significant number of AMTs entering retirement age, but their knowledge and experience are soon going to be lost forever. Artificial intelligence and robotic technology may help in some arenas, but they will never replace the hands-on work that only humans can perform.

There is a partial solution available, one that could free up a lot of time spent on maintenance and thus ease the shortage to some extent. The other solution is more radical: pay AMTs on par with pilots. Why does it make sense that a captain in a new long-range business jet receives upwards of $300,000 a year, while the director of maintenance, who is responsible for the entire fleet, might make $150,000 or, rarely, $200,000 a year? There is so much competition for mechanically oriented workers that the only way to bring more people into aviation is by paying them more and treating them better. But that’s another story.

Here is where the rubber hits the road: I call it the maintenance burden.

When someone or a company acquires an aircraft, it comes with a maintenance burden. The burden is unavoidable and essential for safety. Inspections, parts replacements, and repairs must be done, or the aircraft not only becomes unsafe to fly, but its value can drop considerably. Most aircraft end up being retired or parted out when their maintenance burden becomes unsustainably expensive.

When developing a new aircraft, the OEM that makes it has to come up with a maintenance program, including inspections of various types at certain intervals, parts replacements at mandatory times, and recommendations on servicing that will keep the aircraft healthy and safe.

Now I understand that OEMs are aware of the maintenance burden that comes with their aircraft. I also know that many manufacturers of turbine aircraft participate in Maintenance Steering Group processes (the latest is MSG-3), which are used to establish the initial maintenance requirements for the aircraft and its components. MSG-3 is also used to modify those requirements, for example, extending an inspection interval based on data that shows it isn’t needed as often or vice versa.

Although there is a process, I do wonder whether something like MSG-3 or whatever the OEMs do internally works to ultimately reduce the maintenance burden. Any mechanic who has completed an inspection on an aircraft has asked themselves, why am I looking at this wing bolt or structure or whatever every however many hours when it never has shown a problem? Do the OEMs spend much effort on trying to reduce the maintenance burden? Or is this one of those tasks that no one wants to work on because it’s not as much fun as designing a new aircraft?

I have never worked on business jets or airliners, so I can’t comment from experience about their maintenance burdens. I have done hundreds, maybe thousands, of 100-hour and annual inspections on light aircraft, and it is clear that the OEMs of these aircraft have never gone back to figure out what really needs to be inspected or replaced and what can be left until a later inspection.

Just for fun, let’s look at the maintenance burden on the flight school fleet in the U.S. There are roughly 1,500 flight-training organizations and flying clubs in the U.S. and about 10,000 training airplanes, according to online sources.

Many schools aren’t aware that some OEMs offer fleet maintenance programs that are less burdensome than the 100-hour inspection, so to keep this simple, we’ll assume they’re all doing 100-hour inspections. If these airplanes fly 1,000 hours a year each, that’s 10 million flight hours. Divide by 100, and that’s 100,000 inspections every year. A 100-hour inspection on a simple airplane like a Cessna 172 takes at least 15 hours, and that’s without fixing any discrepancies. So that’s 1,500,000 person-hours per year. A full-time employee works about 2,080 hours a year, so to accomplish those inspections would take 721 AMTs.

Now, what if OEMs created a more reasonable inspection program that maintained the same level of safety without requiring redundant inspection items, such as checking the wing bolts on a Cessna 172 every 100 hours? Say the heavy inspection went to every 300 hours. Now the training fleet needs only 33,000 inspections per year, and that cuts the workload requirement by two-thirds, to 240 AMTs from 721.

This simple example shows that by reducing the maintenance burden, OEMs could help lower the pressing need for AMTs. Obviously, the need for 500 fewer AMTs isn’t going to make a huge difference, but what if every OEM made it a priority to examine its products’ maintenance burdens more closely? They would also have to work with vendors to examine their products’ maintenance burdens.

I suspect, although I can’t prove it, that many of the maintenance requirements that we must comply with came from historical data or even best guesses at what would be appropriate. After all, there is zero scientific basis for the 100-hour requirement. It was just someone at the FAA who thought it seemed like a good idea, as far as I’ve been able to determine.

The maintenance burden doesn’t just impose a resource requirement on the aviation industry; it also has a safety component. In February, researchers Daniele Paolo Scarpazza and Joseph Hutter published a paper in which they examined the effect of maintenance-induced failures on general aviation safety. They found through statistical analysis of NTSB data that in the first hour after maintenance, “hazard rates are 33.8% higher than baseline” and “in the 0- to 200-hour range of time in service after inspection, aircraft causes are responsible for a 23% average increase in accidents and serious incidents.”

It’s entirely possible that there isn’t much scope to reduce the maintenance burden a significant amount, and perhaps this is wishful thinking. I commend OEMs that work to reduce the maintenance burden and would enjoy learning more about how they accomplish this. The fact remains, however, that there is a shortage of AMTs, and something is going to have to be done before aircraft have to be grounded because no one is available to work on them.