The US Air Force has a problem. While it bets its future on the stealth of the F-22 and F-35 fighters, that stealth has come at a cost: reduced weapon loads. To be stealthy, the aircraft both have to carry all of their weapons in internal bays, significantly limiting how many bombs and missiles they can carry to strike at targets on the surface and defend themselves from other fighters.

Without mounting weapons on external hard points on its wings—and creating a much bigger radar target as a consequence—the F-22 can carry just two air-to-air missiles and two JDAM bombs—though the new, smaller Small Diameter Bomb II (SDB II) allows it to carry eight bombs and two air-to-air missiles in the same space. The Air Force's F-35A fighters delivered so far aren't cleared for combat, and the first wave of F-35s being delivered to the Marine Corps (Block 2B) are restricted to two bombs and two air-to-air missiles because the software for more weapons hasn't been finished.

So, what are these multimillion-dollar aircraft supposed to do once they've emptied their weapon bays? That is where the Air Force's research and development plans, detailed in the 2017 Defense Department budget request being sent to Congress this month, come in: the Air Force wants to develop an arsenal plane. Defense Secretary Ashton Carter described the arsenal plane as "a flying launch pad for all sorts of different conventional payloads. In practice, the arsenal plane will function as a very large airborne magazine, networked to 5th-generation aircraft that act as forward sensor and targeting nodes.”

In other words, the arsenal plane will be a networked bomb and missile server, flying high and possibly far away from the target zone, launching weapons in response to targeting requests by the stealthy fighter aircraft as they get in close to the targets. But here's perhaps the most intriguing part of the whole arsenal plane concept: they will be created from some of the oldest aircraft already in the Air Force's inventory, "essentially combining different systems already in our inventory to create wholly new capabilities,” Carter said.

It's an idea the Air Force essentially stole and dusted off from the Navy. In the 1990s, the Navy was considering "arsenal ships" to carry mixes of missiles—big ships with relatively small crews and lots and lots of vertical launch cells that would be fed target data from aircraft and other ships. The Navy ended up repurposing Ohio-class ballistic missile subs into a version of this, converting their 22 launch tubes to carry seven Tomahawk cruise missiles each—for a total of 154. But it set the larger concept aside because of the cost—and the expense of some of the Navy's other ship programs.

Ironically, it's the cost of the Air Force's other aircraft programs that is driving them to convert existing airplanes into arsenal planes. So, which of the Air Force's old dogs will be trained to shoot where the fighters point?



















One of the leading candidates for the job is the B-52. Capable of carrying about 70,000 pounds of weapons, the Stratofortress has already played the arsenal ship role, to a degree, over Afghanistan, where it has dropped GPS-guided bombs in a sort of virtual close-air support mission. And in January, Boeing started delivering a system that will dramatically improve the B-52's performance in that role, innocuously called the 1760 Internal Weapons Bay Upgrade.

Up until now, the B-52, widely known in the service as the "BUFF" (for Big Ugly Fat F**ker), could only deploy "smart" weapons (GPS and laser-guided bombs, guided stand-off missiles, and the like) from external weapons pylons. But the 1760 upgrade basically turns the B-52's internal rotary bomb bay adapter (the Common Strategic Rotary Launcher, used for air-launched cruise missiles) into a "dial-a-bomb" system for conventional guided weapons, letting networked targeting data be passed to a selected weapon before it is rotated into position and launched.

This will let the B-52 carry up to eight additional JDAM bombs (up to 2,000 pounds each)—bringing the aircraft's total possible JDAM load to 20. But the same rotary system can (and will soon) accommodate the Joint Air-to-Surface Standoff Missile-Extended Range (JASSM-ER)—a conventional guided attack missile with a range of more than 575 miles. And it will also carry the Raytheon-built Miniature Air Launched Decoy-Jammer (MALD-J) "missile"—a turbojet-powered drone decoy and jammer with a range of more than 550 miles that can be remotely programmed to appear to be any sort of aircraft to enemy radar and electronic surveillance, and it can actively jam the radar of air defense systems.

It's conceivable that the rotary weapons bay could be adapted to other weapons that can get guidance from other aircraft—including the AIM-120 Advanced Medium Range Air-to-Air Missile used by fighter aircraft, anti-radiation missiles to take out radars, and even the SDB II. Those weapons could also be carried on the weapons nodes on the B-52's wings or in arsenal plane-specific launch pods designed to reduce the drag on the aircraft.

But the B-52 isn't the only old dog potentially in this show. The 1980s-era B-1 bomber has a number of advantages over the older BUFF. The B-1B Lancer can currently carry more conventional ordnance than the B-52: 50,000 pounds on external hard points and up to 75,000 pounds (as much as the B-52 can currently carry overall) in its internal bomb bays. It already has rotary weapons racks that could deploy up to 48 JDAM bombs or 24 JASSM missiles. And while not yet deployed with them, the B-1B could conceivably carry up to 144 SDB II bombs.

The B-1B has another major advantage: speed. Capable of supersonic flight, the B-1B could be better at keeping up with F-22 and F-35 formations, even if it was operating well behind them.

Bombers are not necessarily the only option. The Air Force could also choose to convert older cargo aircraft into the arsenal plane role. The C-130 Hercules and C-17 Globemaster III have been tested as launch platforms for the MALD-J, and transport airplanes have been pressed into service as bombers in the past.

Variants of the C-130 have been used as a bomber in the past—in Vietnam, it was used to drop 15,000-pound BLU-82B "Daisy Cutter" bombs to create landing zones for helicopters. It has also been used to drop the Massive Ordnance Air Blast (MOAB) bomb—the biggest non-nuclear bomb in the military's inventory. But those have been basically pushed out the back door.

The C-17 has also been used as a bomb dropper. It has a number of advantages as an arsenal plane over the C-130, with more than double the payload capacity, higher speed, and greater range. Its operating ceiling is nearly double the altitude of the C-130, at 45,000 feet.

For now, the arsenal plane concept remains just that: a concept. No program has yet been launched, as the idea is still in development. And given the delays facing the F-35 program, it might be a while before there can be any significant integration work done to test the arsenal plane concept anywhere but the drawing board. It would also require a wholly new sort of air combat doctrine to be developed to put the arsenal plane into use.