Subject: Number Fifty-One in the Series--North American P-51 Mustang (4 of 10)

From: [email-masked]
Date: 11 Feb 93 17:17:27 GMT

>From [email-masked]

The next Army contract for Mustangs consisted of an order on August 
24, 1942 for 1200 NA-99 versions with the USAAF designation of P-51A.  
Unlike the A-36A, these aircraft from the start were meant to be 
fighters, not bombers.  The first P-51A flew on February 3, 1943, and 
the first deliveries began the next month.  In the event, only 310 
P-51As were actually built between March and May of 1943 before 
production was switched over to the Merlin-powered P-51B.  

These aircraft had the same external stores capability as the A-36A 
Invader, but had no dive brakes and no fuselage guns, the armament 
being limited to four 0.50-inch machine guns mounted in the wings.  
The inboard pair had 350 rpg and the outboard pair had 280 rpg.  An 
under wing load consisted of two 250 lb, 325, or 500-pound bombs.  
Maximum takeoff weight rose to 10,600 pounds, but maximum ferry range 
was increased to 2350 miles.  The P-51A had the Allison V-1710-81 
engine rated at 1200 hp for takeoff and 1125 hp at 18,000 feet, with 
significantly better high-altitude performance than the V-1710-39 of 
the P-51.  

Because of the thin wing cross section, the wing guns lay almost on 
their sides and the ammunition belt feeds had to be built with some 
rather sharp kinks in them in order to direct the bullets into the 
guns.  This awkward arrangement resulted in many gun jams, 
particularly after maneuvers in which high g-values were pulled.  

Three production blocks were built with the following serials: 

43-6003/6102 	P-51A-1-NA 
43-6103/6157 	P-51A-5-NA 
43-6158/6312 	P-51A-10-NA 

Of the 310 P-51As built, 35 of them were fitted with twin-K24 camera 
installations and had their guns removed.  These were redesignated 
F-6B.  

Another 50 examples went to the RAF, becoming Mustang IIs.  These 
planes replaced the NA-91s diverted from RAF Mustang IA orders for 
conversion as USAAAF F-6As.  The RAF serials of the Mustang IIs were 
FR890/FR939.  Deliveries were made late in 1942.  Mustang II FR901 was 
fitted with special deep-section fuel tanks beneath the wings for 
ultra-long-range flying.  

One P-51A was given to the US Navy for evaluation (BuAer #57987).  

Specifications of P-51A-10-NA: 

One 1200 hp Allison V-1710-81 twelve-cylinder Vee liquid cooled 
engine.  Maximum speed was 340 mph at 5000 feet, 360 mph at 10,000 
feet, 380 mph at 15,000 feet, and 390 mph at 20,000 feet.  Range on 
internal fuel was 750 miles at 300 mph at 10,000 feet.  Range with two 
125 Imp. gall. drop tanks was 2000 miles at 266 mph and 2350 miles 
at 228 mph.  An altitude of 5000 feet could be attained in 2.2 
minutes, 10,000 feet in 4.4 minutes, and 20,000 feet in 9.1 minutes.  
Service ceiling was 31,350 feet.  Weights were 6433 lbs empty, 8600 
lbs normal loaded, and 10,600 lbs maximum loaded.  Wingspan was 27 
feet 0 1/4 inches, length was 32 feet 2 1/2 inches, height was 8 feet 
8 inches, and wing area was 233 square feet.  

The first P-51A group was the 54th, which remained in Florida for 
replacement training.  Later, P-51As went to Asia with the 23rd, 311th, 
and 1st Air Commando Groups.  Almost all of the P-51As served in the 
China, Burma, India (CBI) theatre of operations.  On November 25, 
1943, the 530th Fighter-Bomber Squadron of the 311th Fighter Bomber 
Group flew the first of the Mustang's long-range escort missions, 
using drop tanks to escort B-24 Liberators in an attack on Rangoon, 
Burma, a round trip of nearly 900 miles.  

The F-6Bs, on the other hand, served in Europe, mainly with the 107th 
Tactical Reconnaissance Squadron based in England.  

Sources:

  American Combat Planes, Ray Wagner, Third Enlarged Edition, Doubleday, 
  1982.  

  The American Fighter, Enzo Angelucci and Peter Bowers, Orion Books, 
  1987.  

  War Planes of the Second World War, Fighters, Volume Four, William 
  Green, Doubleday 1964.  

  United States Military Aircraft since 1909, Gordon Swanborough and 
  Peter M. Bowers, Smithsonian, 1989.  

  Fighting Mustang: The Chronicle of the P-51, William N. Hess, 
  Doubleday, 1970.  

  Classic Warplanes: North American P-51 Mustang, Bill Gunston, Gallery 
  Books, 1990.  

  Famous Fighters of the Second World War, Volume I, William Green, 
  1967.  

  British Military Aircraft Serials, 1912-1969, Bruce Robertson, Ian 
  Allen, 1969.  

Joe Baugher       AT&T Bell Laboratories    2000 North Naperville Road 
		  Naperville, Illinois 60566-7033.   (708) 713-4548