Subject: Number Fifty-One in the Series--North American P-51 Mustang (3 of 10)

From: [email-masked]
Date: 10 Feb 93 17:31:50 GMT

>From [email-masked]

In 1940, the US Army had given its permission for the initial British 
Mustang delivery to proceed, with the proviso that two of the NA-73s 
destined for England be made available to the Army for tests free of 
charge.  In a separate contract dated September 20, 1940, the two 
aircraft delivered to the Army were to be the fourth and tenth 
production NA-73s, and the planes were to be designated XP-51.  

The fourth and tenth NA-73s were duly delivered to the US Army in May 
of 1941 for testing at Wright Field, Ohio.  They bore the designation 
XP-51 and were assigned the serial numbers 41-038 and 41-039.  They 
were initially unpainted except for national insignia and the black 
antiglare panel over the forward fuselage ahead of the pilot.  The 
Army painted the serials 1038 and 1039 on the fin and on each side of 
the nose, together with the WRIGHT arrowhead emblem on the rear 
fuselage.  Much later, they were both painted olive drab overall.  

The testing of the two Wright Field XP-51s was rather slow at first, 
almost as if the Army didn't really want to bother with these 
airplanes and that they were some sort of nuisance that the Army 
wished would just go away.  Some authors have suggested that there 
were dark and evil motives behind the Army's reluctance to test the 
XP-51s.  However, the slow pace of the testing of the XP-51s can 
probably be blamed more on bureaucratic inertia than on anything all 
that sinister.  At that time, the Army was overloaded with other test 
programs, the Lockheed P-38 Lightning, Bell P-39 Airacobra, and 
Republic P-47 Thunderbolt being thought to meet all the Army's 
requirements for fighter aircraft.  Furthermore, the Mustang was a 
"foreign" type not built to any American specification, and was 
therefore way down on the Army's list of priorities.  

Nevertheless, the testing of the XP-51s did eventually get underway at 
Wright Field, and the Army's test pilots reported very favorably on 
the performance of these planes.  Inexplicably, no Army orders were 
forthcoming.  Much later, the Senate Special Committee to Investigate 
the National Defense Program (better known as the "Truman Committee", 
after its chairman Sen. Harry S Truman of Missouri) was given the 
task of investigating the system under which military production 
contracts were awarded during wartime conditions.  They looked 
specifically into the reason why the Army had sat on its hands for so 
long before ordering any examples of the Mustang, an airplane which 
had such demonstrably superior performance.  Some insiders claim that 
NAA President "Dutch" Kindelberger had been asked to pay bribes in 
exchange for a production contract, but that he had refused all such 
demands in no uncertain terms.  The primary cause of the long delay in 
Army acquisition of the Mustang may be somewhat less sinister.  The 
Mustang may have been the victim of the "Not Invented Here" (NIH) 
syndrome, in which the Army looked askance at an upstart aircraft 
which had not been designed in response to any of its official 
requirements.  

Only after Pearl Harbor did the US Army finally agree to order the 
Mustang for its own use.  General H. H. "Hap" Arnold, Chief of Staff 
of the USAAF, was instrumental in breaking up the bureaucratic log-jam 
and getting the Army to relent and order the Mustang for its own use.  
On April 16, 1942, the Army finally ordered 500 NA-97s.  The NA-97 was 
a ground attack version and was designated A-36A (in the attack series 
rather than the fighter series) and was assigned the name *Invader*.  
Serial numbers were 42-83663/84162.  

The A-36A differed from previous Mustang versions in having a set of 
hydraulically-operated perforated door-type dive brakes mounted at 
approximately mid-chord on both the upper and lower wing surfaces 
outboard of the wing guns.  Underwing racks were fitted for two 
500-pound bombs.  A built-in armament of six 0.50-inch machine guns 
(two in lower fuselage, four in the wings) was fitted.  The engine was 
the Allison V-1710-87, rated at 1325 hp at 3000 feet.  Normal and 
maximum loaded weights rose to 8370 pounds and 10,700 pounds, and the 
maximum speed in clean condition fell to 356 mph at 5000 feet and 310 
mph with the two 500-lb bombs fitted.  With the bombs, range and 
service ceiling were 550 miles and 25,100 feet respectively.  

The first A-36A flew on September 21, 1942.  Deliveries of the Invader 
were completed by the following March.  The Invader equipped the 27th 
and 86th Fighter Bomber Groups based in Sicily and in Italy.  They 
initially were painted in olive-drab and light-gray finish and were 
painted with yellow wing bands and yellow circles around the national 
insignia.  Both of these Groups arrived in North Africa just after the 
end of the Tunisian campaign.  They saw their first action during 
aerial attacks on the island of Pantelleria.  The A-36A was involved 
in the taking of Monte Cassino, and participated in the sinking of the 
Italian liner *Conte di Savoia*.  

Several sources list the Invader as not being particularly effective 
during combat.  It seems that this is not strictly correct.  Although 
losses during low-level attacks were rather high, the A-36 was 
actually a good dive bomber and it was a stable and effective ground 
strafer.  The engine was very quiet, and it was often possible for an 
A-36 to get nearly on top of an enemy before he realized that an 
attack was imminent.  Dive bombing was usually initiated from an 
altitude of 10,000 feet to 12,000 feet, with bombing speed held to 
around 300 mph by the dive brakes.  The bombs were dropped at an 
altitude of 3000 feet, and pullout was at approximately 1500 feet.  
The Invader was fairly rugged and easy to maintain in the field.  The 
A-36A was able to take a considerable amount of battle damage and 
still return to base.  

The A-36s did not see very much air-to-air combat, since it was 
generally believed that it was no match for the Bf 109 at high 
altitudes and that it was therefore best for A-36 pilots to avoid such 
encounters if at all possible.  If air-to-air combat was unavoidable, 
it was thought best to force the battle down to altitudes below 8000 
feet, where maximum advantage could be taken of the A-36A's excellent 
low-altitude performance.  Although it was not a fighter, the Invader 
claimed 101 enemy aircraft destroyed in air-to-air combat.  

A sort of urban legend has sprung up about the A-36A's dive brakes.  
According to some stories, the dive brakes of the A-36A were next to 
useless and were deliberately wired shut at the manufacturers so that 
they could not be used.  This story is totally incorrect.  On the 
contrary, the dive brakes proved to be quite effective in combat.  The 
origin of this legend seems to have been in the United States, at a 
time before the Invaders first went overseas.  It seems that A-36A 
pilots were told by their officers in the USA that their dive brakes 
would be all but useless in combat and it would be best if they simply 
wired them shut.  This turned out to be incorrect, and the dive brakes 
were used to great effect throughout the Sicilian campaign and the 
Italian invasion.  

One A-36A was supplied to the RAF in March of 1943 for experimental 
purposes.  Its RAF serial number was EW998.  

A-36A Ser No 42-83665 is on display at the WPAFB Museum in Dayton, 
Ohio.  This may be the sole surviving Invader.  

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