The
F-15C may still have an undefeated aerial combat record, but the 38-year-old aircraft could be slated for retirement if the U.S. Air Force decides not to fund a major structural life-extension program.
Air Combat Command (ACC) chief Gen. Mike Holmes says it could cost $30-40 million per aircraft to keep the Eagle soaring beyond the late 2020s, including rebuilding the center fuselage section, among other refurbishments. “We’re probably not going to do that,” he tells Aviation Week.
The better answer, he says, is to rapidly begin buying more fighter aircraft, at least 100 per year. That includes ramping up
Lockheed Martin F-35A Lightning II output once the low-observable fifth-generation aircraft matures, but also successive purchases of air superiority jets under the service’s new Penetrating Counter-Air (PCA) program.
WANTED: F-15C SUCCESSOR
F-15C role could initially be assumed by AESA-equipped F-16
Penetrating Counter-Air would free up F-22 to do F-15C’s job
Air Force mulls “Century Series”-like fighter procurement
OA-X is trailblazer for PCA/F-X acquisition
Service wants to buy 100 fighters per year
The F-15C is operated primarily by the Air National Guard (ANG) in support of the homeland defense mission, capable of intercepting and shooting down adversary fighters, bombers and cruise missiles. ANG Director Lt. Gen. Scott Rice sent shockwaves through the F-15 community on March 22 when he admitted to Congress that plans are being hatched to retire the 235-aircraft single-seat F-15C fleet and the twin-seat D-model trainers in favor of Lockheed Martin F-16s upgraded with active, electronically scanned array (AESA) radars.
In December, the Air Force put
Raytheon on contract to replace the mission computers in its F-16 fleet, providing “near-fifth-generation aircraft computing power” with twice the processing output and 40 times more memory. This upgrade is the bedrock on which future Fighting Falcon improvements will be based, including the radar upgrade. The
Northrop Grumman APG-83 Scalable Agile Beam Radar and Raytheon Advanced Combat Radar could compete for that work.
The ANG has an urgent operational need to install AESA radars on 72 of its F-16s, delivered in batches of 24 and 48 units depending on acquisition authority and funding beginning in fiscal 2018.
That plan has been talked about for some time, but Rice’s comments before Congress suggest these upgraded F-16s could, without serious capability gaps, fulfill the role now performed by the Eagle. But the F-15C carries eight
Raytheon AIM-120 Advanced Medium-Range Air-to-Air Missiles compared to the F-16’s six, along with two heat-seeking AIM-9Xs as backup. The Eagle’s wider radar aperture offers longer-range target detection, tracking and engagement of threats. It flies at twice the speed of sound and is more maneuverable than the F-16.
The service says the F-15 retirement proposal is just one of many being considered as part of its “planning choices” process for fiscal 2019 that began last fall.
Holmes says the F-15 remains capable, but the cost of rebuilding the center fuselage section will likely be too great.
The proposal to retire the F-15C Eagle puts Boeing’s proposed “2040C” upgrade plans in doubt. Credit: Boeing
The F-15 program office at Wright-Patterson AFB, Ohio, which supports the F-15C/D and F-15E Strike Eagle fleets, has been working to keep the type flying through 2045 via capability and structural upgrades, including a wing replacement effort in 2022-28.
Last August,
Boeing received a five-year contract valued at up to $254.2 million for fatigue testing of the F-15C and F-15E models. Two test articles—FTA7 (F-15C) and FTA7 (F-15C)—are undergoing accelerated structural life testing at Boeing’s fighter facility in St. Louis to figure out how long the F-15s can fly and which components fail first. Then the Air Force will know the true life-extension cost.
Raytheon began upgrading the Eagle’s radar to the APG-63(V)3 AESA configuration in 2010. Last November,
BAE Systems began full-scale development of a next-generation electronic-warfare suite for the Eagle and Strike Eagle under contract to Boeing. That F-15 Eagle Passive/Active Warning and Survivability System replaces the obsolete Tactical Electronic Warfare System, which has been the aircraft’s primary self-defense suite since delivery in the 1970s. The prospect of retiring the Eagle puts all these upgrades, collectively worth billions of dollars, at risk. It also dashes Boeing’s hopes for the “F-15 2040C.” Some of the capabilities being considered are fourth-to-fifth-generation communications, conformal fuel tanks, an infrared search-and-track sensor and quad-pack air-to-air missile racks.
Boeing points out that no formal decision has been taken, and it continues to promote “cost-effective” capability upgrades to the service, but there are capacity concerns, since too few F-22s were purchased before the line was shut down in 2012.
“The F-15C was specifically designed for the air superiority mission,” Boeing says. “It has an undefeated, combat-proven record and has enough service life to continue flying for years to come.”
ACC says it is developing a 30-year aviation plan that extends into the mid-2030s, and these types of force structure proposals are being considered as part of that road map. Holmes says since Operation Desert Storm 25 years ago, the Air Force has been buying too few aircraft, approximately 20 per year, mainly the Lockheed Martin F-22 and F-35, which took painfully long to deliver and cost too much. The average age of the fighter force is now 27-28 years. The F-22 buy was truncated at 187, compared to the original Cold War request of 750, and the F-35 still is not mature.
The majority of the F-15Cs are flown by the Air National Guard for homeland defense. Credit: U.S. Air Force
Holmes says a minimum of 100 new fighters are needed per year to reverse this situation and begin rejuvenating the force. He wants to expand the F-35A build rate to 60 per year, but only after it completes development, to avoid upgrade costs.
Air Force Assistant Vice Chief of Staff Gen. Stayce D. Harris tells Congress that the service cannot afford to drop below the minimum operational requirement of 55 fighter squadrons, and would rather grow to 60, about 2,100 aircraft. But it would prefer a healthy force of 55 fighter squadrons with enough pilots and maintainers to support operations than a stressed and undermanned force of 60 units.
ACC says it must retire some fleets to unlock money and personnel to transition to the F-35 and future PCA platform, while still modernizing the F-16 and F-22 fleets. The F-16 and F-15E Strike Eagle are relatively young, with plenty of service life left. The Air Force tried and failed to retire the Fairchild Republic A-10 Warthog, so the F-15C is the next obvious cut.
“We’re trying to work out that mix,” Holmes says. “One of those options is, what year does the F-15C go away?”
He says money being spent on F-22 upgrades will maintain its advantage over its Russia and China adversaries. “If the F-15s go away, eventually those F-22s will move into that role, so we need to get to Penetrating Counter-Air [for the high end],” he says.
PCA was born of the Air Force’s one-year Air Superiority 2030 study, which wrapped up last year. A follow-on 18-month analysis of alternatives will deliver its recommendations to ACC in 2018. Holmes says the Air Force is discussing various acquisition strategies and authorities with Congress to shorten or avoid the typically lengthy engineering and manufacturing development phase if the proposed aircraft is mature enough.
After the PCA study, the service hopes to move quickly into the prototyping and flyoff phase. The OA-X light-attack aircraft program is seen as a trailblazer for the next fighter buy.
Holmes wants to take advantage of the three-stream adaptive cycle engines being developed by
General Electric and Pratt & Whitney under the Air Force Research Laboratory. However, the service could decide to field an initial batch of fighters sooner, powered by an existing engine, perhaps the F-22’s Pratt & Whitney
F119 supercruise propulsion system, he says.
He compared this type of acquisition plan to the Century Series during the Cold War, in which six distinct aircraft models were fielded in rapid succession—a mix of fighter-bombers and interceptors—each bringing improved capabilities.
John Venable, a former airman and defense policy analyst at The Heritage Foundation, does not believe the F-16 is a viable alternative to the F-15C, and it will take many years to complete the F-16 AESA radar upgrade anyway. He says radar size matters due to physics, and the F-15’s dish is significantly larger. There are not enough F-22As to fully assume the F-15’s role right away, and there is little hope of Lockheed restarting the production line, due to cost and dated technology. He doubts the Air Force can develop and field another aircraft in the time line needed before critical F-15C life-extension and force structure decisions must be made.
“The F-15C is still a great airplane,” Venable says. “It doesn’t have the maneuverability of the latest Russian aircraft or French
Dassault Rafale, but the biggest thing it has going for it is tactics. What happens with those squadrons?”
The proposed retirement is a serious issue for the ANG, which is run by the states. Sen. Elizabeth Warren (D-Mass.), whose state is home to the 104th Fighter Wing, an F-15C unit, raised the issue with Air Force leaders during a congressional hearing. They stressed it was predecisional, and the ANG’s adjutant generals are being consulted as studies continue.
John Goheen, a spokesman for the National Guard Association of the U.S., says the ANG would prefer to see these aircraft modernized, not retired. He acknowledges that the F-15C fleet presents a large bill at a time of constrained budgets and competing priorities, but the units in question are highly skilled in the air superiority mission, an Air Force core competency. “They provide the bulk of the defense of the nation’s air sovereignty and also deploy overseas,” he says. “These are busy aircraft and our preference would be for them to be modernized.”
The service says it is still studying the proposal, and cannot say how much it would save by retiring the fleet. The total operating cost of the F-15C/D fleet was $1.3 billion in fiscal 2016.