Short on cash and determined to prioritize new stealth warplanes, the U.S. Air Force is busily trying to rid itself of all 350 of its slow- and low-flying A-10 Warthog attack planes—this despite the heavily-armed twin-engine jet’s impressive combat record stretching back to the 1991 Gulf War.

But the flying branch still needs to support American troops on the ground—the Warthog’s raison d’etre. With that in mind, around 20 highly experienced A-10 pilots and engineers are working on unofficial specifications for a successor to the Warthog.

The group started off with using the original A-X program requirements that resulted in the Warthog starting nearly 50 years ago. Even though technology has advanced since the 1960s, the fundamentals of what is required for the close air support mission have not changed.

“There is a lot that can be made better than the A-10,” says Pierre Sprey, a former Pentagon official and aerospace engineer who originated the Warthog concept. “There is simply no question that we can make it better. The airplane was in a lot of ways a disappointment to me because of where it came out.”

That said, the A-10 is by far the most survivable aircraft for the low-altitude, low speed CAS mission. But almost every aspect of the A-10 can be vastly improved using modern materials and construction techniques, Sprey says.

But be careful! The key to producing a new warplane quickly, on time and to budget is to use the best existing tech rather than trying to invent entirely new hardware and software.

A-10 releasing decoy flares. Air Force photo

Matching the Warthog

The basic requirements for a “Warthog 2.0" are that it retains the Warthog’s current capabilities. “These are the things we hold as the minimum requirements going forward in kind of a follow-on CAS platform,” says one of the two A-10 pilots leading the group behind the prospective Warthog replacement project. “The slow speed and tight turn radius is what allows us to get below the weather and have a rapid rate of re-attack especially with the flexibility of the gun.”

As such, in a next-generation CAS aircraft, the pilot must have good visibility—which is why a round, expansive “bubble” canopy is crucial. “In an air-to-ground mode, being able to look out over your shoulder and behind you—not at threats, but the ground you just attacked or to keep an eye on the friendlies is a critical capability,” the A-10 pilot says.

Because CAS missions often take place at very low altitudes and low airspeeds—anywhere from 150 knots to 300 knots—the aircraft must be able to perform a two-G sustained turn at a rate of five degrees per second with a turn radius of no more than 2,000 feet.

The instantaneous turn rate—that is, how quickly a plane can wheel around in the first few seconds of a maneuver—would have to be better than 20 degrees per second while pulling six Gs. The aircraft must also be able to remain less than one mile from a target between attacks while pulling no more than two Gs—except for the roll-in to the attack and the time its leaving the area.

“The tight turn is important so that we can not only operate in a narrow valley if we need to, but lets says it’s reduced visibility, and we’re kinda poking our way through that visibility, the ability to do that slowly and being able to turn when you see a big hill coming is important,” the pilot says.

But one of the A-10’s major shortcomings is its anemic twin General Electric TF-34 turbofan engines. A follow-on aircraft must have a lot more thrust.

“The number-one problem with the A-10 is that we’re underpowered,” according to the pilot. “We need a way to get our airspeed back quicker and we need the ability to take-off at max gross weight at high-density altitudes.”

The A-10 cannot take off at its maximum weight in Afghanistan and must either off-load weapons or fuel. The next-generation aircraft must be able climb out of a runway at maximum gross weight at a rate of the 4,000 feet per minute at a density altitude of 20,000 feet.

Further, it must be able to operate out of a 3,000-foot runway at sea-level with a full fuel load and an internal gun. Ideally, it should be able to operate out of austere 1,500-foot runways.

A cruise speed of at least 360 knots is desirable, a pilot says. Initially, the group believed that it would be best for a next-gen aircraft to cruise at 480 knots with a dash speed of 540 knots. However, with Sprey’s input, the team came to the conclusion that such a requirement would be aerodynamically incompatible with a tight turn radius at low airspeed.

“What we need and don’t have is the capability to rapidly get airspeed back after an attack,” the pilot says. “Also, while airspeed can help response time, it’s loiter time that really makes response faster because it allows you to be at the battlefield, ready to attack.”

Thus, the prospective aircraft needs to have a minimum combat radius of 150 nautical miles with at least four hours on station time with internal fuel, the pilot explains.

An A-10 fires its gun. Air Force photo

Arming the new plane

The new aircraft would have to be able to make a minimum of 20 attacks on infantry targets or 11 attacks on tanks during a single sortie. With precision-guided rockets, the new aircraft could potentially increase those numbers by an order of magnitude.

Additionally, the Warthog 2.0 would also need to be able to track and kill moving targets from ranges greater than eight nautical miles while flying at altitudes above 20,000 feet.

To accomplish this the new aircraft would need to carry 15,000 pounds of weapons ranging from general purpose unguided bombs to cluster munitions, laser-guided bombs and GPS-guided Joint Direct Attack Munitions.

It would also have to be able to fire 2.75-inch rockets—ideally something like the laser-guided Advanced Precision Kill Weapons System—plus at least six anti-tank missiles similar to today’s Maverick.

The aircraft would also need to be able to carry both versions of the 250-pound Small Diameter Bomb and potentially the AIM-9X air-to-air missile for self-defense. Ideally, it could be fitted with the AIM-120 radar-guided air-to-air missile, as well—but that’s not necessarily crucial.

But it is imperative that the aircraft carry a gun similar to the General Electric GAU-8 30-millimeter cannon installed on the A-10.

In terms of avionics, a next-generation aircraft would have to have all of the capabilities found on the modernized A-10C. The upgraded Warthog already has advanced data-links including the Situation Awareness Data Link and Variable Message Format link. It also has a direction finder to zero in on and interrogate pilot survival radios.

The new aircraft should have better terrain avoidance systems and improved displays in the cockpit. It should also be equipped with a better targeting pod, such as a Litening Gen IV or another such system with a video data-link.

The new aircraft would also need to retain a helmet-mounted display capability similar or better than the Thales Genetex Scorpion that is currently mounted on the A-10.

In a perfect world, the Warthog 2.0 would also have a 360-degree infrared sensor capability and a terrain following radar. It would be fitted with a next-gen data-link, the pilot says.

In terms of survivability, any next-generation CAS aircraft must have two engines and multiple redundant systems that can take a number of hits, the pilot points out. The aircraft must be able to withstand impacts from small arms such as 7.62-millimeter and 14.5-millimeter machine guns and even 23-millimeter cannon fire.

It should also be able survive a hit from a man-portable air-defense missile like the SA-18.

The Warthog 2.0 should be equipped with advanced missile warning sensors and the latest digital radio frequency memory jammers to elude the larger and more capable surface-to-air missiles such as the SA-19. “We want to be able to defeat the latest, greatest, common SAMs we might encounter on the battlefield,” the pilot says.

The A-10 pilot cautions that many of the items on the wish list are placeholders. Some of the capabilities might not be compatible with an affordable and effective aircraft design—though the goal would be to field a plane with a unit price of less than $20 million and costing less than $15,000 per flight hour to operate.

Of course, instead of developing a new plane to succeed the A-10, the Air Force could simply keep the Warthogs it’s got.

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