The Beechcraft L-23 Seminole, subsequently known as the U-8, was the designation used by the United States Armed Forces for the Beechcraft Twin Bonanza and Queen Air aircraft within its fleet.
In 1951, the United States Army conducted an evaluation of the Model 50 Twin Bonanza at Fort Bragg, North Carolina, which led to the procurement of four Model 50s as YL-23s, delivered in early 1952.
Additional Model 50s were ordered as L-23As, and Model B50s were purchased under the L-23B designation.
These orders constituted the bulk of Twin Bonanza production in 1952 and 1953, with the first L-23A delivered in February 1953 and the final L-23B in April 1954, just before the Korean War concluded.
In 1955, the United States Air Force commissioned a single Model C50 Twin Bonanza for evaluation, designated as XL-23C; it was the sole L-23 variant not supplied to the US Army, as the Air Force did not place any subsequent orders.
The following year, the Army resumed receiving L-23s when Beechcraft delivered six Model D50s, designated as L-23E.
Then, in January 1957, the Army took delivery of the first L-23D, which was based on the Model E50 Twin Bonanza.
In 1958, the remaining L-23A and L-23B aircraft in service, with some having crashed, were sent back to the Beechcraft factory.
There, they were upgraded to the same standards as the newly built L-23Ds and were subsequently re-designated with new constructor’s numbers and military serial numbers.
Additionally, in 1958, the Army placed an order for 11 RL-23Ds and converted more from the existing L-23Ds.
These aircraft were equipped with belly-mounted radar, featuring either the AN/APS-85 in a large pod or the AN/APQ-86 in a long, narrow pod attached to brackets, along with a modified nose.
In 1958, Beechcraft initiated the development of a variant with an enlarged cabin at the behest of the US Army.
The resulting L-23F retained the same wings and tail but featured a cabin that was longer, wider, and higher, accommodating up to ten people, in contrast to the earlier L-23’s capacity of five.
Beechcraft assigned the internal designation Model 65 to this type and also pursued its development for civilian use, naming it the “Queen Air”.
The first two Model 65s were kept by Beechcraft as prototypes, and the third unit was delivered to the Army in 1960, followed by an additional 23 units over 1960 and 1961.
Specifications
(D50)
Crew
1
Capacity
5 passengers
Length
31 ft 6 in (9.60 m)
Wingspan
45 ft 3 in (13.79 m)
Height
11 ft 4 in (3.45 m)
Wing area
277 sq ft (25.7 m2)
Aspect ratio
7.51:1
Empty weight
3,981 lb (1,806 kg)
Gross weight
6,300 lb (2,858 kg)
Fuel capacity
180 US gal (150 imp gal; 680 L)
Powerplant
2 × Lycoming GO-480-C206,
Air-cooled flat-six,
295 hp (220 kW) each
Performance
Maximum speed
214 mph (344 km/h, 186 kn) at 2,500 ft (760 m)
Cruise speed
203 mph (327 km/h, 176 kn) at 7,000 ft (2,100 m) (70% power)
Range
1,650 mi (2,660 km, 1,430 nmi) at 10,000 ft (3,000 m) and 160 mph (140 kn; 260 km/h)
Service ceiling
20,000 ft (6,100 m)
Rate of climb
1,450 ft/min (7.4 m/s)
Take-off run to 50 ft (15 m)
410 yd (1,230 ft; 370 m)
Landing run from 50 ft (15 m)
458 yd (1,374 ft; 419 m)
Sources
Beech Aircraft and their Predecessors-Alain Pelletier.
