Huff-Daland produced a series of aircraft for American agricultural and military service that began with the HD-1B and ended with the experimental XLB-3 triplane bomber of 1930. While succeeded by the Keystone Aircraft Corporation (itself eventually falling under the Curtiss-Wright brand label), it nonetheless left its legacy with a line of early bombers in service to the United States Army Air Service (USAAS) during the 1920s. During World War 1 (1914-1918), United States Airmen mainly cut their teeth on bomber types of foreign origin and, in the post-war years, there stood a need for an indigenous light bomber platform to which Huff-Daland developed its "XLB-1" prototype.
To this point, the USAAS had committed to the Martin MB-2 (NBS-1) bombers but the service liked what it saw in the Huff-Daland prototype and commissioned for ten as the "LB-1" (the designation stemming from the words "Light Bomber" which reflected the aircraft's primary service category). For testing, a sole aircraft with a crew of three and powered by single a Packard 1A-2500 engine of 800 horsepower (in the nose driving a two-bladed propeller) was used and this example proved the design sound. Construction incorporated a steel tube frame covered over with fabric skin while the biplane wing arrangement remained typical for this period of aviation featuring parallel struts and a single bay configuration. The undercarriage ("tail dragger" type) was wheeled at the main legs and fixed in place. In testing, the aircraft outperformed the current MB-2s - certainly faster than the competing type.
The overall design showcased a maximum speed of 120 miles per hour with a cruising speed of 105 mph, a range out to 430 miles, and a service ceiling of 11,150 feet. Rate-of-climb reached 530 feet per minute. In comparison, the MB-2 reached a maximum speed of 99 mph, a cruise speed of 92 mph, a range out to 400 miles, a service ceiling up to 7,700 feet, and a rate-of-climb of 390 feet per minute.
In its finalized form as the LB-1, the bomber was given a Packard 2A-2500 engine of 800 horsepower. The crew was also increased from three to four and the bombload peaked at 2,750 lb. Defensive armament was a network of 5 x .303 Lewis machine guns on trainable mounts.
Despite the performance jump, Army authorities were not convinced of the merits of operating a single engine bomber over long distances and over enemy terrain. This terminated the LB-1's chances at seeing widespread production and service for attention then shifted to a twin-engined form - the XLB-3 of 1927. However, only one of this model was built as attention shifted once more to a more promising mark - the XLB-5 - which saw 36 of its kind manufactured under the Keystone name.