Boeing XB-38 Flying Fortress: The Unfulfilled Potential

The Boeing XB-38 Flying Fortress was a unique and ambitious attempt to improve upon the iconic Boeing B-17 Flying Fortress during World War II. Designed to address some of the limitations of its predecessor, the XB-38 held great promise as a formidable bomber aircraft. However, despite its potential, the XB-38’s development faced numerous challenges and ultimately fell short of its intended purpose. This article explores the history and legacy of the Boeing XB-38 Flying Fortress.

During the early years of World War II, the B-17 Flying Fortress demonstrated its capabilities as a long-range heavy bomber. However, the US Army Air Forces identified certain areas where improvements were required. These included enhancing the aircraft’s speed, range, and altitude performance, as well as reducing its vulnerability to enemy attacks.
In response to the need for improvement, Boeing proposed a modified version of the B-17 Flying Fortress with increased engine power and improved aerodynamics. The result was the Boeing XB-38, which featured a radical change – it replaced the conventional piston-driven engines with Allison V-1710 liquid-cooled V12 engines, similar to those used on the Lockheed P-38 Lightning.

While the XB-38 showed promise on paper, the transition from radial engines to liquid-cooled engines proved to be a significant challenge. The modifications resulted in delays and cost overruns. Additionally, the V-1710 engines were in high demand for other aircraft, and their availability for the XB-38 program was limited.
The XB-38 underwent rigorous testing to evaluate its performance and viability as a bomber aircraft. The liquid-cooled engines did offer some improvements, including increased speed and altitude capabilities. However, the overall performance gains were not significant enough to justify the effort and resources invested in the project.

As the war continued and other aviation technologies advanced, the XB-38 project faced increasing criticism and doubts about its practicality. In 1943, the US Army Air Forces decided to abandon the XB-38 program due to its limited performance improvements and the need for more reliable and readily available engines.
Despite its failure, the XB-38 project contributed valuable insights to future aircraft development. It highlighted the challenges of transitioning from one engine type to another and emphasized the importance of maintaining production efficiency during wartime.

The Boeing XB-38 Flying Fortress remains a fascinating chapter in aviation history, representing an ambitious attempt to improve the already successful B-17 Flying Fortress. While the project did not achieve the intended results, it played a role in advancing aeronautical engineering knowledge and contributed to the development of subsequent aircraft designs. Today, the B-17 Flying Fortress stands as an enduring symbol of American airpower during World War II, while the XB-38 serves as a reminder of the challenges and risks inherent in pursuing innovation during wartime.