The decision by many airlines to spread their limited flying among more planes than usual to be ready for a sharp increase in demand could also drive more maintenance spending as manufacturers consider requiring some work to be done regardless of flight hours.
Although the airline industry does not expect passenger traffic to rebound to 2019 levels until 2024, the forecasts for spending on airframe maintenance is, that it will recover to 2019 levels by 2022.
For example, most of the tasks related to the air conditioning system need to be done every 2,000 flight hours, normally about six months. But if the plane only flies 400 hours in six months, the check might be moved up to 1,600 hours to account for the longer passage of time.
Airlines with planes “siting on the ground” due to pandemic are cutting costs by delaying some maintenance tasks like changing life vests, testing oxygen bottles and etc. This allows airlines to stop the clock on a category of parts that would otherwise need checks. But this, also means that it will take longer to reactivate planes.
In the highly regulated world of airplane maintenance, the frequency of many tasks is determined by the number of take-offs and landings or flight hours. But others, such as life vests and portable oxygen bottles, have a fixed schedule for replacement.
The mass return to service of grounded aircraft expected over the next two years and this could create a maintenance-demand “bubble”.