The Keystone LB-5 (originally ordered under the Huff-Daland name) was a bomber aircraft produced in the United States in the late 1920s. Its manufacturer nicknamed it the Pirate, but this name was not officially adopted by the

United States Army Air Corps The United States Army Air Corps (USAAC) was the aerial warfare service component of the United States Army between 1926 and 1941. After World War I, as early aviation became an increasingly important part of modern warfare, a philosophical ri ...

(USAAC).

Design and development

The LB-5 was a member of the family of closely related bomber designs that had debuted with the XLB-1 in 1923, and as such, was a large, single-bay, conventional biplane. Like most of the family, it was a twin-engine machine, with engines mounted in

nacelle A nacelle ( ) is a streamlined container for aircraft parts such as Aircraft engine, engines, fuel or equipment. When attached entirely outside the airframe, it is sometimes called a pod, in which case it is attached with a Hardpoint#Pylon, pylo ...

s on the lower wing. The prototype XLB-5 had a single tail fin like the XLB-1, the 10 LB-5 production machines were designed with a triple-finned tail under the Huff-Daland name, but the final batch of 25 was redesigned with twin tails and designated LB-5A.

Operational history

Its

Liberty L-12 The Liberty L-12 is an American Water_cooling#Internal_combustion_engines, water-cooled 45° V12 engine, V-12 engine, displacing and making , designed for a high power-to-weight ratio and ease of mass production. It was designed principally as ...

engines featured

duralumin Duralumin (also called duraluminum, duraluminium, duralum, dural(l)ium, or dural) is a trade name for one of the earliest types of age hardening, age-hardenable aluminium–copper alloys. The term is a combination of ''Düren'' and ''aluminium'' ...

adjustable-pitch propellers built by the Standard Steel Propeller Company of

Pittsburgh, Pennsylvania Pittsburgh ( ) is a city in Allegheny County, Pennsylvania, United States, and its county seat. It is the List of municipalities in Pennsylvania#Municipalities, second-most populous city in Pennsylvania (after Philadelphia) and the List of Un ...

, (forerunner of the

Hamilton Standard Hamilton Standard was an American aircraft propeller (aircraft), propeller parts supplier. It was formed in 1929 when United Aircraft and Transport Corporation consolidated Hamilton Aero Manufacturing and Standard Steel Propeller into the Hamilto ...

Propeller Company). At least nine tests of

tensile strength Ultimate tensile strength (also called UTS, tensile strength, TS, ultimate strength or F_\text in notation) is the maximum stress that a material can withstand while being stretched or pulled before breaking. In brittle materials, the ultimate ...

were made of its propeller blades between 1925 and 1927, one of which reported failure after 34 hours of flying time and 10 hours of testing.Miller, Dr. Roger G. "Four 'Caterpillars' and a funeral documents on the crash of the Huff-Daland XLB-5." ''Air Power History,'' Fall 2002. On 28 May 1927, while at altitude near

Reynoldsburg, Ohio Reynoldsburg is a city in Fairfield County, Ohio, Fairfield, Franklin County, Ohio, Franklin, and Licking County, Ohio, Licking counties in the U.S. state of Ohio. It is a suburban community in the Columbus, Ohio metropolitan area. The population ...

, the XLB-5 prototype (AC serial 26-208) experienced catastrophic failure of its right engine when a blade separated from the hub with explosive power, tearing the engine apart. Shrapnel sprayed the five-man crew, which included 2nd Bombardment Group commander Major Lewis H. Brereton, flying co-pilot, and all except the nosegunner immediately parachuted. The nosegunner died in the crash, and the gasoline-soaked wreckage subsequently exploded and burned on the ground.

Variants

Keystone LB-5 rear right quarter 060417-F-1234P-004

;XLB-5 :Prototype (1 built from LB-1) with single tail fin ; LB-5 :first production batch with triple tail fins (10 built) ; LB-5A: second production batch with twin tails (25 built)

Operators

; *

Specifications (LB-5)

References

Notes

Bibliography

* Taylor, Michael J. H. ''Jane's Encyclopedia of Aviation''. London: Studio Editions, 1989, p. 559. * ''World Aircraft Information Files''. London: Bright Star Publishing, File 899 Sheet 09.

External links

National Museum of the USAF XLB-5 fact sheet

National Museum of the USAF LB-5 fact sheet

National Museum of the USAF LB-5A fact sheet

{{USAF bomber aircraft LB-5 Light bombers Keystone LB-5