The A-16 | Can a Viper turn into a Warthog?

If you were to choose an existing aircraft to be the basis for a heavy close air support platform, the F-16 would probably not be your first choice. Created with the explicit goal of being a lightweight dogfighter, the Fighting Falcon (more commonly referred to as the Viper) was small in comparison to aircraft such as the Warthog. However, the designers had different plans, and soon they were developing the F-16 into a powerful close air support platform to rival the Warthog, equipped with a massive 30mm cannon.

HISTORY

The story of this crazy Viper conversion program dates back to the 1980s. Both US defense forces and foreign militaries quickly adopted the F-16. Initially limited to short-range air-to-air tasking, newer blocks and models of the F-16 expanded its capabilities to include a variety of air-to-ground tasking.

While few think of the F-16 as a heavy lifter, on paper, the Viper can technically carry a significant payload on its two innermost wing pylons. High payloads could be equipped with advanced pylon mounting systems, like the old LAU-88 for triple mounting Mavericks and later the TER (or triple ejector rack) for Mark 82s and so forth. Today we rarely, if ever, see F-16s with such loadouts, especially in newer tape phases, but the capacity is there.

WARTHOG REPLACEMENT

In the mid-1980s, the Viper platform would come under serious consideration for a new conversion program. At the time, the primary close air support aircraft for the US Air Force was the A-10A. Far more archaic than the Warthog we know today, the A-10A was nevertheless a powerful platform.

As we have discussed in previous videos, the Warthog had several distinct advantages over previous multirole jets. Firstly, it was slower, allowing it to better interact with troops on the ground, observe the battle space, and keep turning and hitting targets again and again without ever losing them from visual range. Its outstanding low-speed performance also gave it the ability to field a huge variety of weapons at once. Even in its early form, the A-10 could linger on station for a long time, effectively spot and counter ground threats, and carry enough stores to do this over and over again far longer than other fixed-wing aircraft at the time. The only drawback was that the A-10, unlike the faster Russian Su-25, primarily relied on fighter cover to operate in controlled airspace.

Despite all of this, there was some hesitation about the Warthog design during the 1980s, primarily due to concerns about its slow speed and the risk of operating in a contested airspace, among other reasons. Many people supported the Warthog design, while many others believed it was already obsolete and dangerous. The latter group would be proven wrong after Operation Desert Storm in 1991, where the A-10 proved indispensable in its intended tasking; however, during the 1980s this tension was tangible, particularly in the Air Force.

While the Air Force seemed uncertain about the Warthog, the US Army pushed for the A-10As to be given to them instead. The Army rightly noted that the Warthog design would be highly effective in covering troops, and if the Air Force wasn’t interested in the aircraft, they would take it. However, the A-10 remained exclusive to the US Air Force, Air Force Reserve Command and the Air National Guard.

At the time, there were concerns about a possible large-scale land war with the Soviets in Europe. The consideration of how to provide a significant amount of close air support led to the approval of certain over-the-top aircraft loadouts for use in the event of an invasion. This included A-10s and F-16s being loaded up with absurd amounts of Mavericks, being mounted on pylons usually restricted, and in triple clusters. Such loadouts were not sustainable—for instance, using four triple cluster racks of Mavericks on the F-16 would quickly burn parts of the airframe after multiple launches, but the overall idea was that these aircraft were not going to last long anyway.

BUILDING THE A-16

In December 1986, after declaring the A-10 inadequate to meet the Army’s 1982 Air Land Battle concept, the Air Force greenlit the A-16 program. It would overhaul the F-16 airframe into a close air support platform, featuring a stronger airframe to support higher stores loads, a 30mm cannon, 7.62mm minigun pods, and presumably support for a wider variety of air-to-ground weapons.

However, resistance to the program began to grow. Many favored the Warthog, and contested the F-16’s suitability as an adequate replacement. Opponents of the so-called A-16 desired the Air Force to develop a follow-up aircraft, similar to the A-10, which they referred to as the mudfighter.

In 1989, the project received a new designation: A-16 Block 60. The project commissioned a variety of F-16s, including F-16A Block 15s and F-16C Block 25s, painted in the distinctive ‘European One’ camouflage.

Detractors noted that the design would still be limiting, albeit in other ways. The A-16 would still carry less than the Warthog, and while it would be faster, some critics argued that this wouldn’t necessarily make it a safer platform to operate over contested airspace, as the F-16 with high stores would be less agile than the Warthog and have a significantly shorter range.

In 1989, Air Force Chief of Staff General Larry D. Welch made it clear in several interviews at an Air Force symposium that he believed the A-16 was the best CAS design available and that no one else had offered an alternative, which is why the project was proceeding. In response to pushback, he said, “I don’t give a damn how you slice that data. I don’t give a damn if you turn it upside down. I don’t care how you look at it. The data does not say mudfighter. The data says A-16.”

Then, Lt. Gen. Michael J. Dugan, deputy chief of staff for plans and operations, said the A-16 “may not be the perfect solution, but it’s damn close. It’s proven, it’s lethal, it’s affordable, it’s supported, and we have in-place infrastructure.” He also went on to say that “the A-10 doesn’t meet evolving requirements and can’t be modified to meet them. It does just what we designed it to do but is no longer adequate. The Air Force doesn’t want the grandson of the A-1, nor is it looking for the son of the A-10.”

At the same time, NATONATO (North Atlantic Treaty Organization) – A collective defense alliance established by the North Atlantic Treaty signed on April 4, 1949, initially ... More commander General John R. Galvin exerted pressure on the air force to make a decision, expressing a preference for the A-16. Galvin said that mudfighter proponents only have a “blurred picture,” assuring that “the issue has been studied enough,” and believed the A-10 had no future in a high-intensity conflict.

The general belief at the time seems to have favoured the idea of F-16s and Tornados working together as the ideal form of close air support, using rocket pods and fast passes on targets.

Nevertheless, budget cuts were forcing the Air Force to accept that they were not going to be retiring A-10s and replacing them with A-16s. On November 26, 1990, a congressional directive to the USAF mandated that they retain a certain number of A-10s, and with this the A-16 concept technically came to an end. While some in the air force wanted the program to continue or at least revive it when the budget allowed, things didn’t look hopeful for the A-16.

However, the desire for a dedicated CAS F-16 remained, and the air force made plans to upgrade Block 30 F-16s to perform CAS and battlefield air interdiction (BAI) missions. This concept would be known as the F/A-16.

This variant would include several early improvements considered advanced at the time, including GPSGPS (Global Positioning System): A satellite-based navigation system that provides precise location, velocity, and timing information to military airc... More support, digital terrain mapping, a modular mission computer, and an automatic target handoff system for data exchange between different pilots and ground units.

The concept was first tested on a special F-16C based at Shaw Air Force Base. Despite being a Charlie model, the F-16 was equipped with an Alpha model HUDHUD (Head-Up Display): A transparent display system that presents critical information directly in a user's line of sight, eliminating the need to loo... More and tail base, and underwent various modifications.

The 174th Tactical Fighter Wing of the New York Air National Guard converted twenty-four F-16A Block 10s in 1991, equipping them with a 30mm gun. Similar to the seven-barrelled GAU-8/A cannon used on the A-10, these F-16s would receive a slightly miniaturized version, called the GAU-13/A, which had four barrels.

This cannon would be fit into the GE GPU-5/A Pave Claw gun pod, which would be attached to the centreline pylon, complete with 350 rounds of ammunition.

At that time, the plan included upgrading new F-16Cs to the same standard and equipping them with the AN/AAS-35V Pave Penny for laser tracking, a feature already present on the A-10. Seven F-16Cs were fitted with these modifications as a test, as well as a single F-16B, which, on top of everything, also received the Falcon Eye FLIRForward-Looking Infrared (FLIR) is an airborne or vehicle-mounted thermal imaging system that detects infrared radiation (heat) emitted by objects and... More system on the nose.

Finally, these new aircraft would have slight armour improvements. A light metallic matrix would support a Kevlar laminate surrounding the crew compartment, flight controls, and compressor.

In addition to these retrofitting endeavours, the F-16 AFTI program was also underway. Supposedly, some A-16 technology was tested on the AFTI for a period, although nothing eventuated from this.

TESTING

Test flights were done with the cannon installed, without any major drawbacks on takeoff, landing, or cruising. However, things were not so smooth once live fire testing began.

Cannon testing quickly revealed what should have been obvious at the start. Especially given that the large and robust Warthog could struggle with firing the huge 30mm cannon.

When testing the 30mm gun pod on the F-16, the entire aircraft shook harshly during each burst. As expected, the vibrations were a serious issue—much more so than on the Warthog. Immediately, pilots reported that the vibrations were so intense that it not only made aiming extremely difficult, it even affected the aircraft’s ability to fly properly, due to the sheer force pushing back from the recoil and combustion of gunpowder.

After these initial tests, it was determined that the severe vibrations were not only due to the aircraft’s small size but also the fact that (unlike the A-10’s strong internal mountings) the cannon mounted in a pod was far less stable, transferring the force through a single pylon to the airframe. The fast speed of the F-16 also made aiming even harder. Furthermore, due to the unavailability of the CCIP system in this configuration, pilots were forced to rely on outdated ‘run-in’ methods to determine the impact points of bullets. After just a few days of testing, pilots were complaining that they couldn’t even control their aircraft when firing the gun, and the best they could do was spray the cannon as an ‘area effect weapon’ at the test range.

Another issue was potential long-term damage, given the heat and gases from the gun were singeing the right-hand side of the fuselage. This was the year 1991, and at the end of the day, the setup was unacceptable—the pods were unbolted and removed.

If there was anything worthwhile about the project, it was the Falcon Eye FLIRForward-Looking Infrared (FLIR) is an airborne or vehicle-mounted thermal imaging system that detects infrared radiation (heat) emitted by objects and... More system. According to one testimony from an M-60 tank driver, several tanks participated in a simulated battle with the F-16D test aircraft. At night, the tanks were to find a place to hide. The F-16 and the tank would then engage in a race to locate each other, with the F-16 utilising FLIRForward-Looking Infrared (FLIR) is an airborne or vehicle-mounted thermal imaging system that detects infrared radiation (heat) emitted by objects and... More and the tank employing its thermal sight. According to the testimony, the F-16’s Falcon Eye consistently located the tank first, with the tank only catching sight of the plane during its attack run.

The F/A-16 was dropped in January 1992 in favour of equipping Block 40 F-16Ds with the Low Altitude Navigation and Targeting Infrared for Night system (or Lantirn).

In a September 1991 issue of the IEEE Spectrum, Pentagon engineer Pierre Spey—who had worked on both the F-16 and A-10 programs—noted that despite Air Force brass looking down on the so-called low-tech A-10, during Desert Storm the Warthog had accounted for two-thirds of the tank kills and nine-tenths of the artillery kills during the campaign while making up only one-twelfth of the aerial force.

COMPETITION

The primary argument in favour of the A-16 was somewhat contradictory. It was claimed that while the A-10 was physically stronger against ground threats, it was vulnerable due to its low operating altitude. Yet at the same time, the A-16 was explicitly designed to negate the F-16’s standard high-altitude strike capabilities in favour of the very same low-level tactics, albeit without the same strength and triple redundancy systems of the Warthog.

What’s more, the general argument against the A-10 as a close air support platform stemmed from a different interpretation of such tasking. Brass wanted close air support to primarily consist of precision strike missions using guided munitions. The A-10’s ability to fly below cloud cover and visual obstruction, its ability to visually pinpoint threats, and its ability to provide continuous suppression through sustained attack runs—as demonstrated in Afghanistan—allow troops to change positions, advance, or retreat, a feat that a single precision strike package cannot achieve unless all enemy targets are neutralized. Essentially, disagreements stem from different understandings of what comprises close air support in general, although the fact that the Soviets themselves adopted a similar design to the A-10—the SU-25 Rook—seems to point to a general belief that lingering air support—while being under higher direct threat—was worth the tradeoff to ensure continual troop support.

CONCLUSION

The A-16 design was on paper an interesting proposal, but in practice it is highly unlikely that it would have outdone the Warthog. The Warthog’s design is uniquely suited for close air support, able to both carry huge stores of weapons and linger on station for long periods of time at low speeds. From Desert Storm onwards, we have seen the Warthog prove itself highly effective, so much so that it has become more popular amongst civilians and soldiers than any other modern close-air support aircraft.

The A-16 likely would have suffered the same issues that the F-4 did in Vietnam when doing close air support tasks, namely, burning through fuel quickly (limiting time on station), having poor visibility or losing track of the target due to high speeds, and being limited in terms of agility due to performance constraints. Just like the F-4, the A-16 would have still been under threat from infrared missiles close to the deck, and unlike the A-10, it wouldn’t have had triple redundancy systems and strong armour to defend against such threats. The A-10 was a result of the close air support situation in Vietnam; therefore, its design was based on experience rather than pure conceptualization.

Nevertheless, the F-16 design is a versatile one, with potential beyond its initial conception. But in this case, turning a Viper into a Warthog is probably a bridge too far.