Historic Aircraft - A Most Versatile Aircraft

The Beech Aircraft Corporation’s commercial Model 18, or “Twin Beech,” may have flown with more U.S. military designations and names than any other aircraft. Beginning in 1940, almost 6,000 of these planes were procured for the U.S. military services, with 2,034 going to the Navy, Marine Corps, and Coast Guard.¹

The original Beech 18—designed by a team led by chief engineer Ted Wells—was built in response to a 1935 request from the Bureau of Air Commerce. The aircraft made its maiden flight on 15 January 1937, and was a success. Civil orders followed. Among the first military variants of the Model 18 were two civilian aircraft in the Philippines that were taken over by the U.S. Far East Air Force in December 1941 (and quickly destroyed on the ground by Japanese air attacks) and six M18R light bomber/training aircraft built for Nationalist China. At least one of the latter was flown by the American Volunteer Group—the “Flying Tigers.”

As early as August 1938 a Beech 18S was test-flown by the Navy, and in June 1940 the Navy placed an initial order for five drone-control aircraft. A total of 11 of these were procured, similar to the C-45 being built for the Army. The Navy planes were distinguished by a windowed cupola above the cockpit for use as drone-control aircraft, providing all-around visibility for the radio-control pilot and radio operator. Two 30-inch radio-antenna masts extended from the top of the cupola. These aircraft were designated JRB-1 in the confusing Navy classification scheme of the time—the “J” for utility, the “R” for transport, and the “B” for Beech.

The JRB-1s were followed by a Navy order for 15 JRB-2 six-seat staff transports, given the name “Voyager.” More JRBs followed with the Navy name “Expeditor” soon being applied to the more than 300 JRBs being procured. The names were rarely used, just the designations. These Navy aircraft reached the designation JRB-4. The Coast Guard acquired seven JRB-4s and JRB-5s between 1943 and 1947; several remained in service until 1956.

Next came the SNB-1 navigation-bombardier-gunnery training aircraft—the “SN” indicating training and, of course, “B” for Beech. The names “Kansan” and “Navigator” were applied to the various training models. Acquired from 1942 on, the SNB-1 was the equivalent of the Army’s AT-11 advanced trainer. For the training role the SNB-1s had a clear “bombardier’s nose” and a dorsal turret mounting twin .30-caliber machine guns.² Under-wing racks could carry ten 100-pound bombs for target practice. The SNB-2 series that followed (initially the equivalent of the Army’s AT-7) included the SNB-2H aerial ambulance and SNB-2P photo variant. The later SNB-3Q was a trainer for electronic-countermeasures personnel.

Used in a variety of roles, these planes were especially valued as short-range cargo and passenger “hacks”—taxis to the uninitiated—and a few flew as VIP aircraft, carrying senior admirals and Marine Corps generals. These aircraft reached the series designation SNB-5. They were so popular that most still were on the Navy’s aircraft lists during the Korean War.

The U.S. Army Air Corps and (from 1941) Army Air Forces acquired 3,839 variants of the Beech 18. After the U.S. Air Force was established as a separate military service in 1947, the C-45 was one of the few fixed-wing aircraft that the Army continued to fly (also using the name “Expeditor”). It flew the aircraft—some ex-Navy as well as ex-Army Air Forces—in a number of roles. The post-1947 Army air service “winterized” several C-45s and fitted several with twin skis for Arctic operations.

Some of these aircraft served in multiple services; for example, the Army’s post-1947 C-45J “Expeditor” No. 89493 originated as an Army Air Forces C-45F transport, was acquired by the Navy as a JRB-4, later modified to SNB-5 standards, and then transferred to the Army. These aircraft served in the U.S. Navy into the late 1960s.

During World War II, 411 Beech Model 18s—likewise called “Expeditors”—were provided to the Royal Air Force under Lend-Lease. Most were used by British forces in Southeast Asia. After the war ex-U.S. military “Twin Beech” aircraft were sold or given to almost 40 other nations for military service. And, of course, many soon were found in civil use.

The basic JRB/SNB was a twin-engine aircraft with the large, radial engines mounted relatively far forward on the low wing. A “tail sitter,” the aircraft could be easily identified by the twin oval, vertical stabilizers with the horizontal tail surface faired into the top of the fuselage. The Army Air Forces flew several C-45s with twin floats. At least three aircraft flown by the Army with the designation UC-45J were fitted with tricycle landing gear; these aircraft had a markedly extended nose. (There also were civil Beech 18 aircraft with floats and nose wheels.)

Beech 18 production finally ended in 1970, the last a Model H18 going to Japan Airlines. This set a record for the longest continuous production of a piston-engine aircraft—32 years with 8,980 civil and military aircraft being built.³ Some are still flying.

1. The most comprehensive account of the Beech 18 is the massive volume by Robert K. Parmerter, Beech 18: A Civil & Military History (Tullahoma, TN: Staggerwing Museum Foundation, 2004). See also see Gordon Swanborough and Peter M. Bowers, United States Military Aircraft since 1909 (Washington, DC: Smithsonian Institution Press, 1989); Swanborough and Bowers, United States Navy Aircraft since 1911 (Annapolis, MD: Naval Institute Press, 1968); and Stephen Harding, U.S. Army Aircraft since 1947 (Shrewsbury, UK: Airlife, 1990).

2. Some Army Air Forces aircraft had dorsal turrets with twin .50-caliber machine guns, and a “tunnel” machine gun could be fitted.

3. Beech Aircraft, later renamed Beechcraft, became a subsidiary of the Raytheon Corporation in 1980. Raytheon merged the firm with another of its product lines in 1990. In 2007 Hawker Beechcraft bought out the Raytheon division and began operating as its own company.

Beech JRB-2 Characteristics

Type: utility/training/passenger aircraft

Crew: 2 + 6 passengers

Gross weight: 7,850 pounds

Length: 34 feet, 3 inches

Wingspan: 47 feet, 8 inches

Wing area: 349 square feet

Height: 9 feet, 4 inches

Engines: 2 Pratt & Whitney R-985-50, 450 horsepower each

Max. speed: 225 mph 

Ceiling: 24,900 feet

Armament: guns, bombs in SNB-1 (see text)