Tuesday, August 23, 2016

The Curtiss H 75, a very overestimated fighter, but used by exceptional pilots



The bad management of the French aeronautical industry by the French government 



Since the meeting of Zürich during the Summer of 1937, a total panic invaded all the French deciders, at both military and politic level. 

They discovered the Morane-Saulnier 406, the fighter they have chosen, was already outclassed by the Messerschmitt 109 B as, also, by the Dornier 17 bomber. 


Worst, with the politics of generalized nationalizations in the French aeronautical industries, the direction staffs were disbanded and the aircraft design teams were beheaded. 

At the same moment, several strikes were hampering the perfecting and the production of the more recent fighters and bombers.

That explains perfectly why none of the 16 Morane 405 pre-series fighters ordered in November 1936 have flown at the very beginning of 1938! 


The French Air Force deciders tried to save the Bloch 150 fighter (successfully but six months too late). 

They accepted, at last, the project issued from Emile Dewoitine of the future D 520 (one full year too late...).



The very expensive ordering of a rather outdated fighter



Fortunately (?), at that time, French deciders discovered a New Savior: Franklin D. Roosevelt, the US president. 

It was suggested to the French deciders that the President will favor a deal to reinforce the French Aviation. 

A famous French test pilot, Capt. Rozanoff, had flown that plane with evident satisfaction. 

{The narrative on this flight test was very interesting, telling that the US Air Force generals were absolutely opposed to any sharing of any information with the French! 

Nevertheless, at this precise moment, the French fighter technology was much ahead of the US one (even it was not the case for the several kinds of aeronautic equipment).}


Indeed, the panicked French government accepted to purchase the Curtiss fighters, as, also, to invest a lot of money for building of the plant needed to build them! 

For an American point of view, that was a multi-dimensional very good deal:

i) Roosevelt don’t like nazis at all. 

ii) Selling fighters to France was very good to absorb the actual unemployment. 

iii) It was a good deal from a financial point of view, the price of the Curtiss H 75 (P 36) being 2,350,000 FF (the Spitfire Mk I was proposed for 2,600,000 FF).

At this very time, French plants working for the French aerial defense had no sufficient money to fulfill their own orders ! 

Indeed, France helped the USA to become a true military power, they were not, actually...



Obviously, a mediatic frenzy was triggered in France by the arrival of the first Curtiss. 

Among the fairy tales published in 1939, it was said by French newspapers that the Curtiss fighter had reached a dive speed of 925 kph (575 mph !). 

Knowing that the VNE of the Curtiss H 75 was only 550 kph, the service ceiling being just under 10,000 m and taking into account her relatively poor aerodynamic layout, such a speed was totally unlikely.


Curtiss H 75 - A rather easy fighter but too much drag...


The Curtiss H 75 was a very maneuverable and reliable fighter in her A1, A2 and A3 subtypes.

The A4 variant, as delivered to France, was unsuccessful, because her Wright R 1820 engine was was not dedicated to fly in fighter planes and could not resist to combat maneuvers: This story giving a very negative view about the proficiency of the French deciders who ordered this engine!  

However, all-round, she was only a moderate fighter

The armament of four 0.3 machine guns was poor, inducing the need to approach too close to their target. 



The top speed were (following the French pilots handbook http://www.gc2-4.com/NMACcpm.htm) :

  • 415 kph  at sea level,
  • 424 kph    at  1,000 m
  • 451 kph    at  2,000 m
  • 469 kph    at  3,000 m
  • 486 kph    at  4,000 m
  • 480 kph    at  5,000 m
  • 472 kph    at  6,000 m
  • 460 kph    at  7,000 m
  • 449 kph    at  7,500 m. 
{The contemporary German Messerschmitt 109 B, C or D, flew 20 kph slower, but in 1939, the Emil was 70 kph faster.}

The climbing times of the Curtiss H 75 were:
  • 1,000 m  in   0' 49"                  
  • 2,000 m  in   1' 47"       (last  1,000 m in 0' 58")
  • 3,000 m  in   2' 58"       (last  1,000 m in 1' 01"   =  61")
  • 4,000 m  in   4' 29"       (last  1,000 m in 1' 31"       91")
  • 5,000 m  in   6' 18"       (last  1,000 m in 1' 49"     109")
  • 6,000 m  in   8' 24"       (last  1,000 m in 2' 06"     126")
  • 7,000 m  in 11' 07"       (last  1,000 m in 2' 43"     163")
  • 8,000 m  in 14' 57"       (last  1,000 m in 3' 50"     230")
  • 9,000 m  in 21' 53"       (last  1,000 m in 6' 56"     416").


If the 4,000 m altitude needed only 4' 30", the following 4,000 m needed 10' 30" to climb to 8,000 m: The Curtiss H 75 was totally unable to intercept spy planes, except if she was already at medium altitude when the warning was given.


However, her 1 600 km autonomy was, really, excellent. 


The handling and maneuverability were excellent (the wing loading of the A1 variant ranging from 122 kg/m² to 130 kg/m², following the kind of mission).

Michel Détroyat gave the following time values for a 360° turn (Source : Curtiss Hawk H 75, J. Cuny & G. Beauchamp, Docavia #22:
  • 12" for the Curtiss H 75,
  • 15" for  the Dewoitine 520
  • 18" for  the Morane 406.

The Pratt & Whitney was very reliable for the first 3 standards(A1, A2 et A3) in French service. {The last engine (Wright 1820) - fitted in the A4 version - more powerful (1 200 hp) was a total failure for a fighter.} 


This last discrepancy of the Curtiss fighter was the consequence of her engine which offered 1065 Hp for only 5 minutes before being limited to 950 Hp. 

With this later power, her top speed dropped to 460 km/h... 

This may explain these planes have been given only to very experienced pilots.



Given to the better French pilots


Obviously, these fighters were affected to the Groupe de Chasse I/5 in which the elite of the French pilots were gathered. 

Among them, Jean-Marie Accart and Edmond Marin La Meslée were the most famous with respectively 15 and 20 victories from September 3, 1939 to June 15, 1940. 

All were very well trained and have a perfect awareness of their forces as also of their weakness. 


This group was the top scorer of French Groupes de Chasse during that period.
Very often, I wonder what if, in place of their Curtiss fighter, the Groupe de Chasse I/5 used Dewoitine 520... or Nieuport 161.


Given to normal pilots, the Curtiss H 75 will be completely forgotten, as she was in other countries...

Nevertheless, the December 7, 1941, during the Pearl Harbor Japanese attack, this fighter was the first to down a Mitsubishi A6M2 Zero, a very good job... 


No comments:

Post a Comment