XB-35 Flying Wing was a product of a long period of experimentation by the most renowned designers of the history of aviation community. It was the US’s first attempt of building an all-wing heavy bomber.

During World War II, when it appeared that Nazi Germany might defeat Great Britain and the Soviet Union, the US Army Air Forces felt the need for a large bomber with intercontinental range. They aimed to build such a plane that will cross the Atlantic and hit Germany with a large bomb load. Aviation pioneer John Northrop spent years developing the concept of such an all-wing aircraft, trading the weight and drag of a conventional fuselage and tail for greater speed and range. Northrop devoted his career in proving that the ‘all-wing concept’ can be used in a ‘practical’ aircraft. Such plane that does not need a traditional fuselage and tail assembly would generate less drag as it moved through the air. The air saved resistance therefore could be used in other areas such as higher speed and the ability to carry a greater load.

Jack Northrop’s XB-35 was a marvelous aircraft. With no need to impound the payload within a slender and heavily-stressed fuselage, that weight would be evenly circulated across most of the lifting surface. As a result, the overall structure of the plane became lighter and more efficient. Jack Northrop saw this formidable requirement as made-to-order for his flying wing concept. He realized that if the fling wing is freed from the weight and drag of a conventional fuselage and tail, it would fulfill the requirements.

In appearance, the XB-35 resembled a silver teardrop from the side and nearly disappeared if viewed directly from the front. Four Pratt & Whitney R-4360 engines of the plane mounted internally, remaining close to its leading edge. The XB-35 Flying Wing could carry a 10,000-pound bomb load a distance of 10,000 miles. With a wing span of 172 feet and a length of only 53 feet, XB-35 stood 20 feet off the ground. Its shape; same span and degree of sweepback of a B-2 bomber; made it a generation ahead from aircrafts of the 1930s and 1940s. Each of the engines drove a pair of ‘counter-rotating four-bladed propellers’. The propellers had a long extension shaft and a complex gearbox.

Only downfall the XB-35 had was the complicated drive train; to be precise, the propeller gear boxes. After several complains, the manufacturer soon replaced the dual propeller arrangement by a single propeller and the 3-blade propeller by a 4-blade type which also increased the overall performance of the plane.

Numerous equipment failures had already delayed the plane’s development by more than a year before XB-35 Flying Wing made its first appearance on June 25, 1946 from the run way of the Northrop Aircraft Co to Edwards AFB. The first flight proved to be a success, and test pilot Max Stanley said that he would never have known that he was piloting a flying wing if he hadn’t looked behind him. Unfortunately, this first flight was the only trouble-free flight the plane ever had. Chronic problems with the propellers and the complex gear boxes ruined the innovative bomber’s bright future.  

The US government acquired 15 B-35s; of them, two were experimental planes and 13 were service test versions. A further order of 200 B-35Bs was cancelled in June 1943 as the manufacturer could not deliver them on time. This left only three B-35s to be completed (two X-models and one Y-) but these three accumulated only a little number of hours in the sky. The YB-35 flight test program lasted only a few months in mid-1948. The single flying YB-35 was in cargo space for over a year before being totally scrapped in 1949.

In order to save the program, the US government ordered the remainder of the test models to be transformed into jet power. The US Air Force thereafter decided to authorize modification of two YB-35s by installing eight jet engines. These two planes were redesigned as YB-49. Another YB-35A was later tailored with installation of six jet engines and became the YRB-49A.

At the same time, the rival Consolidated Aircraft Corporation started working on its design, similar to Jack Northrop’s one - destined to become the Convair B-36. Though XB-35’s concept was innovative, it never a mass production. Its 172-foot wingspan, sweepback angle, and total wing surface area however were incorporated in the design of the B-2.