Boeing X-32 – So Ugly it Failed

Continuing the series about ugly aircraft, even the Military manage to get involved in trying to design ugly aircraft! To any fighter, or ex-pilot, anything with something that looks like it has a sharp nose, goes fast and makes a lot of noise is an outstanding aircraft! Of course, the chopper pilots would roll over in the corner and say it is a complete and utter waste of precious chopper fuel!

Unfortunately, Boeing got this one wrong after a fiercely fought competition with Lockheed.

The Boeing X-32 was an experimental aircraft that was developed by Boeing to compete in the Joint Strike Fighter (JSF) Program against Lockheed Martin’s X-35. Despite displaying some innovative features and fulfilling all the requirements of the United States Marine Corps, Air Force, and Navy, the X-32 fell short of Lockheed’s X-35s and never made it past the Joint Strike Fighter test programme. 15 years later, Lockheed’s aircraft test aircraft was announced as the winner and became known as the F-35 Lightning II. While X-32 was praised for being less complex, easier to manufacture and displayed exceptional performance, among the aircraft enthusiasts, it will be remembered for its chin-mounted air intake, which gave the aircraft a unique shape.

In 1993, the Defence Advanced Research Projects Agency (DARPA) launched the Common Affordable Lightweight Fighter project (CALF). The project's purpose was to develop a stealth-enabled design to replace all of the United States Department of Defence's lighter-weight fighter and attack aircraft, including the F-16 Fighting Falcon, McDonnell Douglas F/A-18 Hornet, and vertical/short takeoff / vertical landing (V/STOL) AV-8B Harrier II. On the other hand, a review from the Pentagon on fighter aircraft had led to the initiation of the Joint Advanced Strike Technology (JAST) program, which, among other objectives, aimed to include the US Navy in the Joint Strike Fighter Program. This program would develop aircraft, weapons, and relevant technology that would replace the US aircraft F-16, A-10, F/A-18A-D, AV-8B, and EA-6B, and the UK aircraft Harrier GR7, GR9s, and Tornado GR4.

In 1994, after much fighting, bickering and the like, the U.S. Congress ordered the two to be merged into one program under the JAST name. The merged program (CALF and JAST) would continue under the name JAST until the engineering, manufacturing, and development phase, when it was renamed the Joint Strike Fighter Program.

Numerous countries went on to participate in the project, with the UK contributing GBP200 million in November 1995 for the concept development phase (10% of the total value). The DoD received proposals from 4 companies for this program. Lockheed Martin, McDonnell Douglas, Northrop, and Boeing had all submitted their prototype STVOL proposals; however, the DoD awarded contracts only to Lockheed Martin and Boeing. One major departure from previous projects was the prohibition of the companies from using their own money to finance development. Each was awarded $750 million to produce their two aircraft – including avionics, software and hardware. This limitation was to primarily even the playing field and ensure new and innovative designing and developing of structures and concepts.

The contracts were awarded in November 1996, with each company required to develop two prototypes that would demonstrate the following functions:

1. Conventional takeoff and landing (CTOL) – primarily an Air Force requirement.

2. Short takeoff and vertical landing (STOVL) – primarily Marine Corps requirement.

3. Carrier takeoff and landing (CV version) – primarily Navy requirement.

Considering that the JSF program was the biggest program since the 60s and 70s Lightweight Fighter Program that resulted in F-16 and F/A-18, both Boeing and Lockheed were expected to throw everything into the bucket to win the competition.

Boeing's strategy for a competitive advantage was to offer substantially lower manufacturing and life-cycle costs by minimising variations between the different JSF versions. The X-32, therefore, was designed around a large one-piece fibre composite delta wing. The wing had a span of 9.15 meters, with a 55-degree leading edge sweep, and could hold up to 20,000 pounds (9,000 kg) of fuel. The purpose of the high sweep angle was to allow for a thick wing section to be used while still providing limited transonic aerodynamic drag, and to provide a good angle for wing-installed conformal antenna equipment. The wing would prove a challenge to fabricate.

Boeing went for the direct lift thrust vectoring system, which would suffice to complete the vertical landing and short takeoff requirements. This required the engine to be placed very close to the cockpit, shifting the centre of gravity towards the front of the aircraft to allow the aircraft to hover. The location of the engine was highly unusual for a fighter plane, as they would normally have the engine placed towards the rear part of the plane.

Nevertheless, Boeing made it work using a Pratt & Whitney F119-PW-614 engine that would produce thrust in excess of 42,000 pounds. The power plant would be a derivative of the F-22 Raptors' afterburning turbofan.

The aircraft would also have an air intake area in the front (chin) of the aircraft, which would feed sufficient air to enable the aircraft to hover. Using a chin air intake gave the aircraft a weird shape but would also make the aircraft famous through the nickname “Monica”, referring to a well-known White House intern, who at that stage was entertaining President Bill Clinton, with her not-so-well-known exploits under the Oval Office desk.

The US Navy would request Boeing to update the design of the aircraft, opting for a conventional tail, which would require changing the delta wing frame. The new design was prepared; however, it would not be incorporated into any of the aircraft as it would be hard to meet the deadline. To fulfil all the DoD’s requirements, Boeing decided to produce two aircraft, with X-32A to demonstrate CTOL and Carrier Trial, while the X-32B would demonstrate the STOVL.

The X-32A made its first flight on 18 September 2000, taking off from Palmdale Plant and heading to Edwards Air Force Base. The aircraft was piloted by Fred Knox. Even though the flight was considered a success as it completed 80% of the projected goals, the aircraft would experience some issues that would result in shortening the flight time from 40 to 20 minutes.

During this flight, the aircraft needed 670 meters (2200 ft) to become airborne at a speed of 280km/h (170mph). It was noted that during the initial phases of flight, the F/A-18s that served as chasing planes found it difficult to keep up with the X-32.

The X-32A would go on to complete 66 flights during a 4-month test phase. It would meet the Air Force’s requirements for CTOL and the Navy’s requirements for Carrier Takeoff. Following the X-32A, in March 2001, the X-32B would complete its initial flight and test the STOVL feature. Similar to X-32A, the X-32B would fly from Palmdale to Edwards Air Force Base. In contrast to the A version, this aircraft’s engine was a direct lift engine and had a butterfly valve to divert the gases of the engine to the thrust vectoring nozzles, which were located close to the aircraft’s centre of gravity. This mechanism would enable the aircraft to use engine gases and provide vertical thrust for short take-off and vertical landing.

The STOVL mechanism was very similar to the AV-8B Harrier II aircraft, which used the jet’s exhaust for thrust vectoring. A special mechanism would prevent the hot gas from recirculating, which could overheat the aircraft.

The X-32B would complete 78 flights during 4 months of testing. One of those flights was the transcontinental ferry flight from Edwards AFB to Naval Air Station Patuxent River. The X-32B managed to meet the Marine Corps STOVL requirements by shifting the thrust from the aircraft’s cruise nuzzles to the lift nuzzles.

The X-32B was also test flown by Phillip “Rowdy” Yates, a naval aviator, who would be given a 20-person maintenance detachment and 2 F/A-18s to serve as chase planes. Yates emphasised that during the X-32 test exercises, he observed that X-32 had no problems with general handling; however, it came short in demonstrating STOVL and supersonic flight using the same configuration. The X-32 would require the maintenance crew to make modifications before switching from one to the other.

Despite the genius design, the aircraft would often suffer from poor power output and engine overheating while in the STOVL mode due to hot air exhaust entering the engine. The testing would conclude in July 2001.

On 26 October 2001, the DoD announced that Lockheed Martin’s X-35 had won the competition. The victory of X-35 over X-32 was mainly attributed to X-35’s performance demonstration, more specifically, when it took off in less than 150m (500 ft), time to go supersonic, and landed vertically. Nevertheless, this program was considered to be a strategic investment by Boeing. Through this program, Boeing made a step closer to perfecting stealth technology and improving design and manufacturing methods.

Consequently, Boeing applied some of these advancements to other programs such as the F/A-18E/F Super Hornet and the X-45A Unmanned Combat Air Vehicle (UCAV). In 2005, the National Museum of the United States Air Force near Dayton, Ohio, became the X-32A’s permanent home.