Given the Russian threat, the United States Air Force should consider adopting some number of F-35B wings for the European theater.

The United States Air Force recently issued a request for proposals (RFP) for a program called the A-10 Thunderbolt Advanced-Wing Continuation Kit—or ATTACK—to fit new wings onto the venerable close air support jet.

(This first appeared in 2016.)

Once the Air Force selects a vendor, there would be a contracting period followed by five years of firm orders plus options for two more years of production. The Air Force intends to order the kit as an indefinite quantity contract—which the service defines as having contract minimum of the first article plus three Low Rate Initial Production articles. The maximum production number would be 112 each of wing sets and 15 kits. The winning bidder would not have to deliver the first low rate production kits until 2029.

The kits would not be sufficient to re-wing all of the so-called “thin wing” A-10s, but the order quantity and timing would be enough to keep enough Warthogs flying in six super-sized squadrons into the 2040s. That means that out of the roughly 280 A-10s in service, about 80 jets would be retired eventually. But the Air Force is only keeping the Warthog in service because of pressure from the U.S. Congress, which has refused to allow the service to retire the A-10. Instead, the Boeing F-15C Eagle is likely going to be on the chopping block.

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Retaining the A-10 will help the Air Force to preserve to preserve the Warthog community’s hard won close air support skills and expertise. However, the A-10 is only really survivable in a low to medium threat environment, thus it will likely be most valuable in counter-insurgency fights. Those types of wars are likely to be with us for decades to come—the United States will likely be in Afghanistan for at least another generation under the current policy. The A-10 could serve as a high-end complement to whatever aircraft is selected for the OA-X program (assuming that effort moves forward into a procurement program) for those types of missions.

That being said, the A-10 is not suitable for a high-end fight against a peer level threat such as Russia or China. In a military confrontation against the Kremlin in the European theatre, the A-10 would not be able to get close enough to a Russian Ground Forces’ motor rifle brigade (MRB)—the most common Russian mechanized unit—to engage because of their heavy organic air defenses. Indeed, such Russian MRBs are essentially mobile anti-access/area denial zones.

Each Russian motor rifle brigade consists of roughly 4,500 troops. In each brigade, there are three motor rifle battalions with roughly 510 soldiers and 43 MT-LBV, BMP-2 or BMP-3 armored personnel carriers and eight 2S12 120mm towed mortars. There is also an armor battalion consisting of 41 tanks and two self-propelled artillery battalions, each with 18 self-propelled guns such as the 2S19 Msta-S. Those are accompanied by a significant air defenses in the form of a battalion of Tor-M2 or Buk M2 or M3 air defenses and another battalion of shorter-range point air defenses including the Tunguska M1 missile and gun system. Those are backed by a support battalion, which includes formidable electronic warfare capabilities and BM-21 multiple launch rocket artillery systems, and another battalion of towed artillery. Essentially, each MRB is a self-contained battle group that can fight completely independently without air support.

The main threats to conventional non-stealth aircraft when dealing with a Russian motor rifle or tank brigade are the mobile Buk M2 and M3 surface-to-air missile batteries. The new Buk M3—which has a range greater than 70 kilometers or about 44 nautical miles—can hit targets flying as low as 50 feet or as high as 115,000ft. Moreover, the Russians claim that the missile system has a probability of kill of better than 0.95. Of course, the Buk-M3 only comes into play if the incoming aircraft survives area air defenses provided by the Russian Ground Forces’ 250 nautical mile range S-300V4 that cover those formations from a distance. Alexey Ramm, editor for military affairs at Russia’s Izvestia newspaper, says that the Buk M3 (and presumably the S-300V4) is able to engage even stealth aircraft such as the F-22 and F-35. However, that claim must be taken with a health dose of skepticism.

But the fact remains, approaching a Russian Ground Forces mechanized brigade from the air in a conventional aircraft such as the A-10 is likely to result in very heavy losses. Moreover, with Russia having mastered long-range precision strike capability with its sea-based Kalibr cruise missiles and air launched X-101 cruise missiles, the Kremlin would be able to target most bases such aircraft might launch from. Thus, NATO’s conventional military airfields might not be available during a full-up conflict.

A potential solution to the problem is the Lockheed Martin F-35B short takeoff vertical landing (STOVL) version of the Joint Strike Fighter, which is currently operated by the U.S. Marine Corps. The United States Air Force could revisit the idea of buying several wings of F-35B aircraft modified for its specific needs to replace some number of A-10 squadrons in order to provide close air support capability in a high-end fight in the European theatre. The STOVL F-35B could operate from partially destroyed runways or even highways converted into semi-prepared airstrips much as NATO planned to do during the closing stages of the Cold War in the mid-1980s. Further, the F-35B could penetrate into the mobile anti-access/area denial bubble that the Buk M3 (and S-300V4) represents—which is something the A-10 cannot do.

Based relatively close to the front line in dispersed makeshift bases (similar to the USMC distributed operations), the F-35B could generate rapid sorties carrying eight 250lbs Small Diameter Bomb IIs to strike at each invading Russian mechanized column. A single flight of four F-35Bs each carrying eight SDB IIs—which is a projected capability for the jet for 2022—would be able to destroy 32 enemy armored vehicles in a single sortie. One of the key performance parameters for the F-35B is to generate four sorties per day. Thus, assuming the F-35B is able to survive against Russian air defenses, four jets flying four sorties per day could potentially devastate a Russian armored brigade. If the number of aircraft were doubled to eight, the effect would be multiplied. Thus, given the Russian threat, the United States Air Force should consider adopting some number of F-35B wings for the European theater.

Dave Majumdar is the former defense editor for The National Interest.