Mission capable rates across most Air Force fleets declined in fiscal 2023, continuing a broad downward trend, according to information provided by the service. Readiness fell predictably in high-demand, hard-used assets and some systems approaching retirement, but the availability of some vintage aircraft continues to hold up well.
Mission capable rates measure the percentage of time an aircraft is able to perform at least one of its core missions, while “full mission capable” rates refer to an aircraft being able to do all its assigned missions. For example, an F-16’s missions include dogfighting, ground attack, suppressing enemy air defenses, etc. Full mission capable rates were not provided. The service has said the way it measures mission capability rates has changed in recent years, with more focus on readiness of aircraft either already deployed or about to deploy and less on stateside aircraft.
The service has said it aims for an mission capable rate average of 75-80 percent. The unweighted average of all fleets in 2023 was 69.92 percent, down from 71.24 percent in fiscal 2022. The rates are not weighted by numbers of aircraft in a particular fleet, and the numbers also include aircraft that were fully divested by the end of fiscal 2023, such as the KC-10 tanker.
Of 64 aircraft types that carried over from 2022 to 2024, 44 saw a decline in mission capable rate—more than two-thirds. Those in decline included most of the service’s biggest, most active fleets.
The F-15C—which is flight restricted due to structural issues and is now about ten years past its planned retirement date—posted the lowest MC rate among fleets with at least a dozen aircraft, at 33 percent. That means that typically, two of three aircraft were not available for action.
Other types available less than half the time included the B-1B bomber, C-5M strategic airlifter, CV-22 tiltrotor, E-3B AWACS, C-130H, and RQ-4B Global Hawk drone.
The B-1B’s rate fell from 54.8 percent to 47 percent, even though the Air Force reduced the size of the fleet two years ago by 17 airplanes but preserved the manpower and maintenance funding associated with the bomber in order to boost its availability. The C-5M’s rate fell from 52.6 percent to 46 percent, despite a decade-long, $10 billion re-engining, avionics, and structural upgrade intended to jumpstart the Galaxy’s flagging availability rates.
In fiscal 2022, the Air Force had:
- No airplane types reporting MC rates below 25 percent
- Five between 26 and 50 percent
- 38 between 51 and 75 percent
- 26 between 76 and 100 percent
In fiscal 2023, those numbers fell to
- One type below 25 percent (the MC-130H, with a zero percent MC rate)
- Nine between 25 and 50 percent
- 26 between 51 and 75 percent
- 28 between 76 and 100 percent
The bulk of those aircraft performing best were in the small and medium cargo/utility categories—notably C-12 variants, with an MC rate of 99 or 100 percent—as well as intelligence, surveillance, and reconnaissance types such as the MQ-9 drone, which specifically turned in an MC rate of 86 percent.
The bomber fleet all performed at less than 60 percent mission capable, with the B-1 at 47 percent, the B-2 at 56 percent and the B-52 at 54 percent. Those figures include a monthslong grounding of the B-2, called a “safety pause” by the Air Force. The previous year’s rates for those three aircraft were 55, 53 and 59 percent, respectively.
Fighters generally checked in between 52 percent—the stealthy F-22’s rate—and 69 percent, the rate for the F-16C, although the brand-new, two-airplane fleet of F-15EXs logged a MC rate of 86 percent. A third F-15EX has since joined the force, and 96 more are coming in the next few years. The venerable A-10C, which the Air Force will divest by the end of the decade, had an MC rate of 67 percent.
The Air Force did not provide an MC rate for its F-35As. However, the Government Accountability Office reported in April that the Air Force’s F-35A mission capable rate as 51.9 percent in fiscal 2023, down from 56 in 2022.
The new KC-46A tanker turned in an MC rate of 65 percent, down from last year’s rate of just under 70 percent. The KC-135, which it will replace, came in at 69 percent.
The T-38 supersonic trainer fleet—overdue for replacement by the T-7A Red Hawk—managed rates between 58 and 70 percent. The oldest T-38As had an MC rate of 63 percent, but the upgraded T-38C only managed 58 percent, while the AT-38B lead-in fighter trainer hit 70 percent.
The E-8C Joint STARS, which has been divested, turned in a final MC rate of 64 percent.
While the Air Force has pointed to low MC rates, obsolescence, and vanishing vendor issues as the reason for divesting or retiring C-135 series types such as AWACS and JSTARS, other C-135 variants—used for signals intelligence, reconnaissance, weather, etc.‚are doing well, between 76 and 87 percent mission capable.
The Air Force said it generally prioritized modernization over readiness in the fiscal 2025 budget request which went to Congress in March. But it included readiness asks in its Unfunded Priorities List, which Chief of Staff Gen. David W. Allvin said were “targeted” to specific fixes and parts that could produce disproportionately large gains in readiness.
AIRCRAFT TYPE 2023 MC% 2022 MC% A-10C 67% 69.70% AC-130J 76% 80.80% AT-38B 70% 74.20% B-1B 47% 54.80% B-2A 56% 52.80% B-52H 54% 59.30% C-12C 99% 98.70% C-12D 100% 100.00% C-12F 99% 95.60% C-12J 100% 100.00% C-130H 44% 68.40% C-130J 72% 74.90% C-17A 76% 77.50% C-21A 100% 100.00% C-32A 88% 88.40% C-37A 93% 94.50% C-37B 91% 91.20% C-40B 88% 89.90% C-40C 91% 90.10% C-5M 46% 52.60% CV-22B 46% 51.90% E-3B 47% 40.20% E-3G 60% 63.90% E-4B 61% 55.40% E-8C 63% 49.20% EC-130H 33% 68.90% EC-130J 63% 67.20% F-15C 33% 45.70% F-15D 55% 58.50% F-15E 55% 51.60% F-15X 85% 84.60% F-16C 69% 70.70% F-16D 65% 68.90% F-22A 52% 57.40% F-35A 51% 65.40% HC-130J 72% 76.40% HH-60G 67% 68.90% HH-60W 67% 60.80% KC-10A 79% 80.40% KC-135R 69% 72.00% KC-135T 67% 69.60% KC-46A 65% 69.90% LC-130H 48% 54.70% MC-12W 100% 100.00% MC-130H 0% 68.50% MC-130J 76% 79.40% MQ-9A 86% 89.90% RC-135S 73% 80.60% RC-135U 85% 79.50% RC-135V 71% 70.00% RC-135W 77% 67.70% RQ-4B 50% 70.80% T-1A 78% 76.30% T-38A 63% 69.50% T-38C 58% 57.20% T-6A 62% 71.40% TC-135W 82% 76.10% TE-8A 79% 83.00% TH-1H 60% 71.70% U-2S 76% 73.50% TU-2S 81% 69.60% UH-1N 78% 81.80% UV-18B 100% N/A WC-130J 68% 64.10% WC-135R 87% 73.30%