L-23 Seminole

Infobox Aircraft
name= L-23/U-8 Seminole


caption= US Army U-8D Seminole liaison version
type= Utility aircraft
manufacturer= Beech Aircraft Corporation
designer=
first flight= 1949
introduced= 1952 (US Army)
retired= 1992 (US Army)
status= Active in general aviation
produced=1952-1961 (L-23A/E)
1958-1963 (L-23F/U-8F)
primary user= United States Army
more users=
number built= 288 (including 71 L-23F/U-8F)
unit cost=
developed from = Beechcraft Twin Bonanza
variants with their own articles= Beechcraft Queen Air

L-23 (later U-8) Seminole was the United States Armed Forces designation for the Beechcraft Twin Bonanza (Beechcraft's Model 50) and Queen Air (Beechcraft Model 65/70/80/88) airplanes in its inventory.

Design and development

In 1951 the United States Army evaluated a Twin Bonanza at Fort Bragg, North Carolina and subsequently ordered four 'off-the-shelf' Model 50s as YL-23s, these being delivered in early 1952. Further examples of the Model 50 were ordered under the designation L-23A and Model B50s were also ordered under the designation L-23B. These accounted for the majority of Twin Bonanza production during 1952 and 1953, the first L-23A being delivered in February 1953 and the last L-23B being delivered in April the following year., shortly before cessation of the Korean War.

In 1955 the United States Air Force ordered a single Model C50 Twin Bonanza under the designation XL-23C for evaluation; this was the only L-23 variant not delivered to the US Army as no further orders were placed by the Air Force. In 1956 deliveries of L-23s to the Army recommenced when Beechcraft delivered six Model D50s under the designation L-23E. In January 1957 the first example of the L-23D was delivered, based on the Model E50 Twin Bonanza. During 1958 the remaining L-23A and L-23B aircraft in service (a few had crashed) were returned to the Beechcraft factory, where they were remanufactured to a similar standard as new-build L-23Ds and then re-designated as such with new constructor's numbers and military serial numbers. [http://home.att.net/~jbaugher/1957.html USAF/US Army 1957 Serials list] retrieved 2007-12-17.] [http://home.att.net/~jbaugher/1958.html USAF/US Army 1958 Serials list] retrieved 2007-12-17.] In 1958 the Army also ordered eleven RL-23Ds with further examples being converted from L-23Ds. These aircraft featured belly-mounted radar, either AN/APD-1 in a large pod or APS-85 in a long narrow fairing mounted on brackets with a modified nose as well.Phillips, Edward H. "Beechcraft - Pursuit of Perfection, A History of Beechcraft Airplanes". Flying Books, Eagan, Minnesota 1992. ISBN 0-911139-11-7.]

Also in 1958 Beechcraft began to develop a variant with a larger cabin at the request of the US Army. The L-23F that emerged had the same wings and tail but up to ten people could now fit in the longer, wider and higher cabin compared to only five in earlier L-23s. Beechcraft gave the type the in-house designation of Model 65 and developed it as a civilian aircraft as well, christening it the "Queen Air". The first two Model 65s built were retained by Beechcraft as prototypes and the third was delivered to the Army in 1960, with a further 23 being delivered that year and in 1961.

Operational history

The first L-23As entered service in 1953 and the type served the US Army for almost forty years, the last U-8Fs being retired in 1992. When US military aircraft designations were revised in 1962, the remaining L-23D, RL-23D, L-23E and L-23F aircraft became U-8Ds, RU-8Ds, U-8Es and U-8Fs. A further 47 Model 65s were ordered in 1962 and 1963 as U-8Fs; one of these was delivered to the Pakistan Army, the only delivery outside the US military (although other nations bought Queen Airs as military aircraft). These were the final new-build aircraft in the series, however the unique Beechcraft Model 87 turboprop proof-of-concept aircraft used in developing the King Air was delivered to the Army as the NU-8F in 1964 (this was later re-designated the YU-21) and a few used Queen Airs were also taken by the Army. Many U-8Fs were modified during their service lives to a similar standard as civilian Excalibur Queen Airs. The most obvious modifications are more powerful Lycoming IO-720 eight-cylinder engines in place of the factory-fitted six-cylinder engines; and bulged main landing gear doors that fully enclose the wheels when the gear is retracted instead of the wheels partially protruding through the doors. Many L-23Ds/U-8Ds and U-8Fs have been registered as civilian aircraft since retirement from military service.

Variants

;YL-23: Four Model 50 Twin Bonanzas evaluated by the US Army as Serial Numbers 52-1800 to 52-1803; 52-1801 subsequently converted to L-23A standard. [http://home.att.net/~jbaugher/1952.html USAF/US Army 1952 Serials list] retrieved 2007-12-17.]

;L-23A: 55 delivered to the US Army as Serial Numbers 52-6162 to 52-6216; many subsequently converted to L-23D standard.

;L-23B: 40 delivered to the US Army as Serial Numbers 53-6153 TO 53-6192; many subsequently converted to L-23D standard. [ [http://home.att.net/~jbaugher/1953.html USAF/US Army 1953 Serials list] retrieved 2007-12-17.]

;XL-23C: One aircraft for evaluation by the US Air Force, Serial Number 55-3465. [http://home.att.net/~jbaugher/1955.html USAF/US Army 1955 Serials list] retrieved 2007-12-17.]

;L-23D: 100 delivered new to the US Army plus 93 L-23As and Bs rebuilt to L-23D standard. New-build aircraft Serial Numbers 56-3695 to 56-3718, 57-3084 to 57-3101, 57-6077 to 57-6094, 58-1329 to 58-1353 and 59-2535 to 59-2543; converted aircraft Serial Numbers 57-6029 to 57-6076 and 58-3048 to 58-3092. [http://home.att.net/~jbaugher/1956.html USAF/US Army 1956 Serials list] retrieved 2007-12-17.]

;RL-23D: variant with belly-mounted radar. Eleven new-build aircraft delivered to the US Army as Serial Numbers 58-1357 to 58-1364 and 59-4990 to 59-4992, plus 29 converted from L-23Ds. [http://home.att.net/~jbaugher/1959.html USAF/US Army 1959 Serials list] retrieved 2007-12-17.]

;L-23E: Six delivered to the United States Army as Serial Numbers 56-4039 to 56-4044.

;L-23F: 24 aircraft based on the Beechcraft Queen Air delivered to the US Army as Serial Numbers 58-1354 to 58-1356, 60-3453 to 60-3463, 60-5386 to 60-5390 and 61-2426 to 61-2430. [http://home.att.net/~jbaugher/1960.html USAF/US Army 1960 Serials list] retrieved 2007-12-17.] [http://home.att.net/~jbaugher/1961.html USAF/US Army 1961 Serials list] retrieved 2007-12-17.]

;U-8D: L-23D redesignated in 1962.

;RU-8D: RL-23D redesignated in 1962, plus fifteen U-8Ds converted after 1962.

;U-8E: L-23E redesignated in 1962.

;U-8F: L-23F redesignated in 1962 and 46 new-build aircraft delivered to the US Army as Serial Numbers 62-3832 to 62-3875, 63-13636 and 63-13637, plus single Beechcraft Model 87 delivered used as NU-8F in 1964 (Serial 63-12902) [ [http://home.att.net/~jbaugher/1962.html USAF/US Army 1962 Serials list] retrieved 2007-12-17.] [http://home.att.net/~jbaugher/1963.html USAF/US Army 1963 Serials list] retrieved 2007-12-17.] and one Queen Air purchased second-hand in 1966 (Serial 66-15365). [ [http://home.att.net/~jbaugher/1966.html USAF/US Army 1966 Serials list] retrieved 2007-12-17.] In addition, one U-8F (Serial 63-7975) was delivered to the Pakistan Army instead of the US Army and two Queen Airs confiscated from drug runners were added to the US Army inventory in 1981 as U-8Fs (Serials 81-13658 and 81-13659). [ [http://home.att.net/~jbaugher/1981.html USAF/US Army 1981 Serials list] retrieved 2007-12-17.]

;U-8G: XL-23C, seven U-8Ds and four U-8Es modified with more powerful engines and enlarged cabin for six passengers.

Military operators

*PAK
*USA

pecifications (L-23D)

[Some information taken from the [http://rgl.faa.gov/Regulatory_and_Guidance_Library%5CrgMakeModel.nsf/0/A59D08A9956B3D778625738C005A2DCD/$FILE/5a4.pdf Beechcraft Model 50 Type Certificate] retrieved 2007-12-19.] aircraft specifications
plane or copter?=plane
jet or prop?=prop
crew=1-2 pilots
capacity=5 passengers
length main=31 ft 6 in
length alt=9.61 m
span main=45 ft 3 in
span alt=13.78 m
height main=11 ft 6 in
height alt=3.51 m
area main=277 ft²
area alt=25.7 m²
empty weight main=5,010 lb
empty weight alt=2,270 kg
loaded weight main=
loaded weight alt=
max takeoff weight main=7000 lb
max takeoff weight alt=3175 kg
engine (prop)=
type of prop=Lycoming GSO-480-A1A6 (Military designation O-480-1)
number of props=2
power main=340 hp
power alt=253 kW
max speed main=270 mph
max speed alt=235 knots, 432 km/h
range main=1,000 mi
range alt=870 nm, 1,600 km
ceiling main=30,000 ft
ceiling alt=9144 m
climb rate main=1,614 ft/min
climb rate alt=8.2 m/s

References

ee also

aircontent
related=
* Beechcraft Twin Bonanza
similar aircraft=
lists=
see also=