Today, the AH-64 Apache attack helicopter is world renown as one of the most capable combat rotorcraft ever to take to the sky, but years before the first Apache flew, one defense firm proposed meeting America’s attack chopper needs with a flying tank of sorts, in the Model 49.
In the early 1960s, the U.S. Army was eager to capitalize on lessons learned from the Bell UH-1 Iroquois, better known as the Huey, in Vietnam. The Huey had proven that helicopters were a viable and effective means of moving troops around the battlefield, but that lesson came at a heavy price. A total of 7,013 UH-1 helicopters flew at different points during the Vietnam War, and an astonishing 3,305 of them were shot down, killing more than a thousand pilots and more than 1,100 other crew members.
With the war ongoing, the Army knew they needed to shift their approach to rotorcraft, and simultaneously began looking for a new, more resilient platform that could be used for rapid troop movements and another more heavily armed platform that could be relied upon for close air support. While the U.S. Air Force could provide support to troops on the ground, their fast-moving jets were just too quick and too vulnerable to hang out low-and-slow over a gunfight. The legendary Fairchild Republic A-10 Thunderbolt II, better known as the Warthog, would eventually become a troop favorite for this role, but it was still more than a decade away from entering service at the time.
So the Army decided to take it upon themselves to build a new air support platform that could take off without a runway, hover over a firefight, absorb lots of punishment, and most important of all, deliver holy hell to enemy fighters below.
The troop transport helicopter effort would eventually result in the development of the Sikorski H-60 Blackhawk series of rotorcraft that have gone on to become ubiquitous throughout the U.S. military. The close air support effort, on the other hand, would eventually mature into the Advanced Aerial Fire Support System (AAFSS) competition, which was won out by the now-defunct Lockheed AH-56 Cheyenne. And while the Cheyenne would itself ultimately be canceled, that wasn’t before beating out the likes of Convair’s own Army air support proposal: a tail-sitting aircraft that wasn’t quite a helicopter, wasn’t quite an airplane, and carried a whole lot of firepower.
The Convair Model 49
Convair was no stranger to offering up unique solutions to military problems by the mid-1960s. A decade prior, Convair had been the firm responsible for developing and testing the NB-36 Crusader, which was a B-36 Peacemaker converted to fly using nuclear propulsion. During that same window of time, Convair was also testing their unusual tail-sitting, vertical launch fighter that also blurred the lines between traditional airplanes and rotorcraft in the XFY Pogo.
Today, some of these concepts may seem impractical or even silly, but in the 1950s and 1960s, the Cold War’s insatiable hunger for new military technology and seemingly unending budget allowances conspired with the already rapidly advancing engineering breakthroughs of the day to create a perfect storm for aviation programs that thought, flew, and fought outside of the proverbial box. Some of these efforts would yield incredible successes, like the high-flying speed demon SR-71 Blackbird or the stealth revolution with a cockpit we call the F-22. Others, however, weren’t quite as successful in practice, even if they seemed incredibly promising in theory. Such was the Convair Model 49.
Like the XFY Pogo, Convair envisioned their Model 49 as a tail-sitting aircraft that featured a two-man cockpit positioned above a huge, circular “wing” of sorts. That circular wing, also called an annular, would house two large ducted fan propellers and have four external pylons that would house fuel, avionics, and weapon control systems.
Like a modern V-22 Osprey, these huge propellers would provide both lift and forward propulsion, but unlike the Ospey, Convair intended to re-orient the cockpit, rather than the props, as it transitioned from hovering to forward flight. The cockpit itself was mounted on a pivoting joint that could move a full 90 degrees, orienting itself perpendicular to the direction of airflow during landing, take-off, and hovering, and then straightening out with the platform itself as it pressed forward through the air.
Heavy weapons and plenty of armor
Learning from the hard lessons of Vietnam, the Model 49 would leverage armor throughout its design that would hold up to all the punishment small arms could dish out. However, the substantial platform still had to be light enough to fly, meaning the armor likely wouldn’t have been heavy enough to hold up to large caliber weapons, rocket-propelled grenades, or surface-to-air missiles.
But sometimes the best defense is a good offense, and that’s where the Model 49 would deliver. Convair’s design called for one XM140 30mm automatic cannon with a mission payload of 1,000 rounds. A cannon of similar size can be found today on AC-130 gunships and Stryker armored fighting vehicles, and this weapon itself would find a home aboard the AH-1 Cobra. In place of the 30mm cannon, the Model 49 design could also utilize a WASP rocket launcher.
Other mounting points would allow for either a pair of remote-controlled XM-134 7.62-mm machine guns or XM-75 40-mm grenade launchers. The machine guns would carry 12,000 rounds of ammunition, with 500 40-mm grenades occupying that space when alternatively equipped. Importantly, each of the weapon turrets could rotate and elevate, making it possible to use them at just about any point in the Model 49’s operations, whether on the ground, hovering in the air, or flying straight forward. Mechanical stops would prevent any of the weapons from being able to shoot the aircraft itself as it adjusted positioning in the air.
Additional ordnance would be carried into the fight on four hardpoints on the bulbous wing, which would allow for additional fuel tanks as well as BGM-71 TOW or other missiles. These hardpoints could also be used to carry massive M40A1C 106-mm recoilless rifles on each side with 18 rounds of ammunition. These weapons had an effective range of better than 10,000 yards and would make short work of armored vehicles and even tanks. The Model 49 did not mess around.
Although prototypes were built, simpler designs won the day
The Model 49 promised to give the Army a platform that could quickly dash between fights, carry lots of firepower, and take off and land without the need for an airstrip, but all of that capability came at the expense of simplicity. The Army saw potential in the Model 49 concept and ordered a series of full-size models for aerodynamic testing, but ultimately, it may have simply been too far out of the box for the Pentagon brass. The AH-56 Cheyenne was also a forward-reaching design, but it borrowed more heavily from established rotorcraft programs with proven performance. Convair’s Model 49 may have seemed viable, but there were simply more question marks to account for with the concept, and question marks tend to increase costs in the best of times, and casualties in the worst.
Ultimately, not even the Cheyenne would find its way into the fight, giving way instead to the AH-64 Apache gunship we’ve all come to know and love. But you can’t help but wonder how different military aviation might look today if the Army had instead opted for a flying barrel covered in guns for its air support needs.