Don’t be fooled by the DoD’s readiness figures

When the DoD talks about the readiness of its aircraft it usually cites mission capable rates. But is that what DoD analysts actually use when looking at the problem? Here are excerpts from Ritschel, Ritschel, and York’s 2019 paper, “Providing a Piece of the Puzzle: Insights into the Aircraft Availability Conundrum.”

While mission capable (MC) rates remain the predominant metric used to assess availability at the unit level, aircraft availability (AA) has become the preferred statistic in the USAF for fleet assessment of operational readiness.

The public cares about the readiness of the fleet, not of particular air wings. The DoD should also be reporting AA, because the services can pull aircraft off the line to keep MC rates up. (Should AA be classified? I don’t think so…)

Here’s more on that:

MC rates are calculated by capturing only the readiness of aircraft that are currently possessed at the unit level (e.g. aircraft awaiting maintenance at a depot are not included in MC calculations). In contrast, the AA statistic accounts for all aircraft in the fleet. In its simplest form, AA is the percentage of time aircraft are available to accomplish mission requirements. It answers the basic question: How many aircraft are ready to fly? The AA rate is calculated using equation 1:

AA is considered a key element of air force readiness. As a result, negative changes in AA rates are concerning to senior leaders. Figure 1 shows the AA rate has declined from a high of approximately 75 per cent in the early 1990s to a current low of about 62 per cent.

So when the DoD talks about readiness of aircraft, they’re almost never talking about the more wholesome and meaningful AA rate, but rather the MC rate. In the GAO’s recent report on aircraft readiness, they collected the AA metric from the Air Force but did not show it.

The authors also found that non-available aircraft hours due to maintenance was growing as a proportion of total cost. I’ll leave you with this:

… The aircraft inventory has decreased by approximately 31 per cent over the past 25 years. At the same time, the age of the air force fleet is also increasing. The average age has increased by approximately 61 per cent, from 17 years in 1991 to 27.4 years in 2017.