One of the Fastest Strangest Airplanes Ever Built

It was a plane that the US Army Air Forces didn't even order. How

ever

, the Douglas XB-42 Mixmaster was designed as a vision of the future and was such a bold departure from conventional bombers that it was impossible to ignore. As the embodiment of Douglas Aircraft Company's aggressive and forward-thinking approach, the XB-42 featured a radically aerodynamic design with a unique propeller configuration and inline engines. It was a strange aircraft with a very different appearance from its contemporaries. But these features were not merely aesthetic. Not only did the far behind enemy defenses. . While the plane's potential was limited by the rapid emergence of jet technology and the end of the war for which it was designed, its legacy endures as a fascinating chapter in the annals of aviation history: a symbol of what could have been and a reminder. of the ephemeral nature of progress in the face of relentless time.

During World War II, daytime precision bombing missions, designed to hit specific military and industrial targets and weaken Axis forces, relied heavily on the Boeing B-17 Flying Fortress and the Consolidated B-24 Liberator. The B-17 could carry up to 4,800 pounds of bombs, while the B-24, with its more efficient wing design and higher-powered engines, could carry up to 8,000 pounds, allowing them to inflict substantial damage on their targets. Both aircraft were equipped with multiple defensive positions, providing them with protection from enemy fighters. How

ever

, as the war progressed, the need arose for a bomber with a longer range that would allow the United States Army Air Force to expand the range of bombing missions, perhaps even eliminating the use of forward bases. , which were often difficult to secure. and keep.

With this in mind, Boeing followed up the B-17 with the B-29 Superfortress, which had an impressive maximum range of 3,250 miles compared to 2,000 miles for its predecessor. However, not only was this B-29 enormous, with a length of 99 feet and a wingspan of 141 feet, but the project also cost a staggering $3 billion, making it the most expensive of throughout the war, which severely limited the aircraft's viability. At the same time, it had become apparent that many bombers were extremely vulnerable to interception by faster and more agile enemy fighter aircraft. While the top speeds of the B-17 and B-24 were 287 and 290 mph, respectively, the German Messerschmitt Bf 109 topped out at 390 mph, and the Focke-Wulf Fw 190 reached 408 mph.

This vulnerability not only threatened the success of bombing missions but also caused significant losses of aircraft and crews. If the Allies could develop faster bombers, it would reduce the window of time during which enemy fighters could intercept and attack them. Additionally, it was believed that higher speeds allowed bombers to operate without the need for fighter escorts, which was particularly important during the early years of the war when most fighters had limited range and therefore , they could not accompany bombers on missions in deep areas. enemy territory. In 1943, Douglas Aircraft Company, which, along with Vega, had been part of the consortium that had assisted Boeing with the production of the B-17, recognized this demand for a bomber that had the greater range of the B-29, but that had the greater range of the B-29.

It would be smaller and more profitable. What's more, by exploring ways to minimize aerodynamic drag and improve propulsion efficiency, they believed it would be possible to create a medium bomber that could reach a top speed of 400 mph, significantly faster than current Allied options in this category. and with a much better chance of evading enemy combatants. Taking the lead, Douglas began developing an aircraft that they believed would meet these criteria despite the lack of a formal request from the military. Rather than modify an existing design, Burton and his team planned an entirely new aircraft from scratch, creating a bomber that would represent a significant break from everything that had come before.

The design they ultimately chose, initially known as the Model 459 but soon given the name XB-42, had a wingspan of 70 feet 6 inches, 53 feet 8 inches long, and a number of unconventional features intended to optimize efficiency. aerodynamics and performance. The most distinctive aspect of the aircraft was its propulsion system. Instead of traditional wing-mounted engines, it used a pair of liquid-cooled Allison V-1710 inline twelve-cylinder engines, known from their use in aircraft such as the Lockheed P-38 Lightning, mounted in the fuselage. Each engine was cooled by intakes on the leading edge of the wings, with the radiators located in the fuselage, and came equipped with a variable speed supercharger.

They were connected to three-bladed counter-rotating coaxial Curtiss Electric propellers located in the tail via long shafts, similar to the two-section shafts found on the Bell P-39 Airacobra, leading to a reduction gearbox. Douglas intended the propellers to have independent, automatic control, along with reversible pitch to reduce landing distances and control dive speeds. These propellers gave the XB-42 its unofficial but widely used nickname Mixmaster, after the popular kitchen mixer, which some said the propellers resembled. To avoid risks to crew members who needed to jump, particularly the danger of being thrown into the rear propellers, the design included an explosive mechanism to separate the propellers from the tail cone during emergencies, improving safety during egress.

The XB-42's unconventional propeller configuration, combined with the clean, unobstructed wing design, helped reduce aerodynamic drag to just 70 percent of that of a conventional twin-engine bomber with tractor propellers. He also put the plane's expected top speed at sea level at 344 mph, with a projected top speed of 410 mph at 23,800 feet. Its operational range at 10,000 feet was approximately 1,840 miles, which could be extended to 5,400 miles by reducing the bomb load and carrying additional fuel, making it well suited for missions that went well beyond enemy lines. Additionally, the Mixmaster featured a tricycle landing gear arrangement, which was becoming more common in military aircraft designs of the time due to the improved forward visibility and handling characteristics it offered on the ground.

The aircraft's all-metal construction and laminar flow wings were also indicative of the advanced design principles applied to the development of new aircraft during the period. Its full four-surface cruciform tail featured a lower fin and rudder assembly to ensure that the aircraft's coaxial propellers did not contact the ground. Unlike most USAAF bombers of the era, which often had crews of up to ten, the XB-42 was required to be manned by only three people: a pilot, a co-pilot/gunner, and a bomber. They were located in non-pressure compartments, with the pilot and co-pilot/gunner seated side by side under distinctive bubble canopies, offering excellent visibility, while the bomber was parked in a glass section at the front of the aircraft, behind of a transparent nose made of plexiglass.

The co-pilot's seat could rotate 180 degrees to allow operation of the weapon control system. Internally, the Meanwhile, defensive armament was minimal, avoiding the heavy armed turrets often found on contemporary bombers. There were a pair of 0.50 inch or 12.7 mm machine guns on each side, integrated into the trailing edge of the wing, with the option to retract into the wings when not required. Its aiming was controlled by the co-pilot using a special observation station in the rear of his cockpit. The range of motion of these weapons was restricted to 25 degrees to each side and could be elevated between +20 and -15 degrees, providing a limited coverage area to the rear only;

Given the aircraft's impressive speed, it was anticipated that enemy fighters would be less likely to attack from other positions. However, the XB-42 was also designed with provisions for two additional forward-facing guns. With the design complete in May 1943, Douglas presented his innovative aircraft concept to the USAAF, which responded with great enthusiasm. This led to the decision, on June 25, 1943, to order two prototype models along with a static test fuselage. With the first prototype ready less than a year later, the . co-pilot. Throughout 32 test flights, the aircraft was carefully studied for improvements. The second prototype, which made its maiden flight on August 1, 1944 from Santa Monica Airfield, also in California, had several differences.

The experimental single bubble canopies were changed to a more traditional single canopy design with the aim of improving communication between crew members, and the nose was covered with plywood after it was shown that plexiglass was prone to cracking. . In an attempt to lighten the aircraft and increase its speed, it was fitted with hollow propeller blades, but these aggravated existing vibration problems, especially when the bomb bay doors were open or the gears and flaps were deployed. The tail was also enlarged in an attempt to counteract the original prototype's tendency to "Dutch roll", a combination of uncontrolled yaw and roll, and the inlets on the wing's leading edges were also made larger to improve airflow. air, helping to keep engines cool. .

However, just two weeks after the second prototype took off for the first time, the Japanese officially surrendered, ending World War II. Now that the urgency for its completion had been significantly reduced, the XB-42 project was put aside. The USAAF began to focus its attention on the development of bombers with the latest jet technology, such as the North American B-45 Tornado. However, Douglas test pilots accumulated 70 hours in the air with the second Mixmaster prototype before officially delivering it to the USAAF in October 1945, where Lieutenant Colonel Fred J. Ascani and Captain Glen W. Edwards took the helm. , adding another 48 hours of flight. flight time.

Most of his flights took place at Muroc Army Airfield in California, which would later be renamed in honor of Edwards following his tragic death in the Northrop YB-49 crash. Although the aircraft did not reach the expected performance marks, nor did it reach the maximum designed speed and range, it did meet the expected rate of climb to sea level, achieved the service ceiling with two engines, and completed takeoff. and landing distance requirements when clearing a 50-foot obstacle. It also showed promise in its overall stability, maneuverability and stall characteristics, and Ascani noted that it was noticeably quieter than many other aircraft due to the location of the propellers at the rear of the aircraft.

On December 8, 1945, Edwards and Warden achieved a new milestone on the second XB-42 prototype by completing a record coast-to-coast flight across the United States, taking off from Long Beach, California, and landing at Bolling Field. in Washington, D.C., about 2,300 miles in just over 5 hours and 15 minutes. The USAAF proudly announced that the plane maintained an impressive average speed of 433 mph during this trip. However, it was not revealed that this speed was significantly aided by the strong tailwinds encountered along the route, and the aircraft's actual speed was closer to 375 mph, although still considered fast for a bomber. Unfortunately, just eight days later, tragedy occurred.

On December 16, it was Ascani's turn to pilot the plane, this time accompanied by Major Hayduck and Lieutenant Colonel Haney. The flight worsened from the beginning, as Ascani was forced to use the emergency system to retract the landing gear after takeoff from Bolling. Approximately 40 minutes into the flight, the cabin began to fill with smoke and the readingsThe instruments indicated that the engines were overheating. Then, in a worrying sequence, both engines failed one after the other. Ascani ordered the other two men to evacuate the plane using their parachutes, which they did safely: Hayduck at 1,200 feet and Haney at 800 feet.

Just as Ascani was preparing to get out of trouble, he realized that he had not ejected the propellers, a necessary step to prevent his companions from colliding with them. He quickly activated the mechanism to separate the propellers and heavy gearbox, which drastically altered the plane's balance and sent it into a tailspin. Ascani managed to exit the plane at 400 feet, barely high enough for his parachute to open properly. He landed at Oxon Hill, Maryland, near where XB-42 eventually crashed. Incredibly, all three men survived, but the Mixmaster was completely destroyed. Subsequent investigation identified a malfunction in the hydraulic system as the culprit for the landing gear problem.

The exact cause of the engine failures remained a mystery, although the fuel shortage was suspected to be due to malfunctioning right engine. The investigation cleared Ascani of any responsibility for the incident. Meanwhile, the first and now only surviving XB-42 prototype underwent a transformation with the installation of two Westinghouse J30 jet engines mounted in pods under its wings, evolving into the XB-42A. This modification increased its speed, allowing it to reach a top speed of 480 mph. However, this still did not match the speeds of emerging aircraft designs, including the XB-43 Jetmaster designed by Douglas themselves. Consequently, the XB-42 project was cancelled.

In 1949, the last remaining unit was finally retired by the US Air Force and delivered to the National Air and Space Museum in Washington, D.C. In 2010, the plane's fuselage found a new home at the National Museum of the United States Air Force in Dayton, Ohio, where it awaits restoration and the opportunity to be displayed in the museum's Experimental Aircraft Hangar as a bold testament. of the groundbreaking World War. 2 aviation technology that wasn't afraid to take risks.