Brown mentiones this in his book Wings of the Navy; he didn't rate the AU-1 very highly.
"The speed for maximum climb rate was 125 knots (232 km/h) from sea level up to 21,000 ft (6,400 m)..."
Climb was certainly impressive, with that immense 13 ft 4 in (4.06 m) diameter Hamilton Standard propeller pulling the aircraft up like a high speed lift, 10,000 ft (3,050 m) being passed in 4 - 6 minutes and 20,000 ft (6,095 m)in 9.6 minutes. Above 21,000 ft (6,400 m) climb speed was reduced three kts per 2,000 ft, but the two-stage two-speed supercharger ensured good climbing capability well above 30,000 ft (9,145 m).
This is certainly contrary to the perception that he wasn't impressed by its climb rate.
Here's what he had to say in short about the Corsair in general:
"There can be no doubt the Corsair was one of the fastest naval aircraft of WW2 and few of its pilots criticised it from a performance standpoint. It had a good range, adequate firepower, an extremely reliable engine and it could absorb a lot of punishment. However, in my view it left much to be desired as a fighter from the viewpoint of manoeuvrability and this same shortcoming was apparent in the dive bombing role in which it saw widespread use. Finally it had a very dreary track record as a deck-landing aircraft; many were the pilots that lauded its high speed performance but decried its lack of affinity with a carrier deck."
Brown explained that his role in assessing the Corsair during the war was during diving trials, where Marine Corps pilots had experiences where fabric was tearing from the elevators during high speed dives. Never a good thing.
Here's his introduction to the Corsair chapter:
"Undeniably unique in appearance among singe-seat fighters of its era, with its reverse-gulled wing, mighty Double Wasp engine and immense windmill of a propeller combining to impart an impression of brute strength, Chance Vought's F4U Corsair was not a comely aeroplane by any yardstick. It was anathema to some pilots and shear ambrosia to others. There were those pilots that acclaimed it as the best single-seat fighter of any nation to emerge from WW2; there were pilots that pronounced it a vicious killer equally dispassionate towards killing its pilot as his opponent. Indeed, few fighters were capable of arounsing within those that flew them such extremes of passion as was the Corsair. Of course, in any shortlist drawn up of the most famous - as distinct from the most efficacious - fighters of WW2, this odd looking warplane will inevitably rank among the classics near the top. Yet, to my mind, the Corsair achieved such a level of distinction despite itself, but then I was never to be numbered among its more ardent admirers;
those that apparently assessed the Corsair solely on the basis of its more glamorous attributes and disregarded the penalties that these invoked."
I think you need to read the book before making such an assumption. He's pretty clear about its faults and although he does admit he wasn't a fan, he wasn't for good reason. It doesn't appear that he flew later models of the fighter variant before the AU-1, but the faults of deck handling and poor stall characteristics were generic to the breed, not just the early ones, so his assessment is not inaccurate in this regard. This after testing the AU-1:
"It was the handling of the AU-1 that served to heighten my distaste for the Corsair, however, for if its ancetor had proffered some unendearing characteristics, they had been multiplied in the descendant. The AU-1 had developed some highly undesirable directional stability and control characteristics, such as requiring almost full right rudder on a deck-landing approach, thus rendering baulked landing the most hazardous of operations. It also displayed a directional oscillation in diving wiht external stores, thus setting up wing rocking and seriously affecting the aiming accuracy."
View attachment 468981Corsair iii by
Grant Newman, on Flickr
Good information, thank you.
But as I wrote above, I generally agree with his opinion on the drawback of Corsairs which he flew.
Perhaps someone who does not agree with it is rare.
My assumption is from the comparison in "Duels in the Sky", and it is for air combat performance.
Brown simply asserted that Fw 190 A-4 could not be bested by Corsair II just due to it's lighter weight. there is no other explanation. but interestingly, in the next section, Hellcat - which had heavier weight than Corsair, is rated to be equivalent to Fw 190 A-4.
In fact, the Fw 190 A-4 was lighter than the Corsair, but the wings were much smaller, so wing loading was much higher than Corsair.
So in the USN test, the Corsair easily beat the Fw 190 in dogfight.
in that test, even with a early type propeller blade which had poor efficiency at high air speed, Corsair showed much faster at low altitude, equivalent at medium altitude and slightly slower at high altitude. in 2 minutes all-out runs.
Fw 190 showed faster optimal speed for sustained climb, but zoom climb of both models were the same after dive.
Considering the performances of both models, it seems difficult to assert something.
However, Brown simply asserted Fw 190 is clear winner just by it's light weight, it lacks explanation.
And he stated that he had limited visibility and control due to his small body which was not suitable for Corsair's cockpit design.
In such a situation, it seems difficult to show the best performance in the air combat.
Besides, I have never seen any information that he actually had a mock dogfight with Corsair against Fw 190 A-4 as USN test. or had any combat sorties with Corsair.
Perhaps it seems to be one of the reasons for the difference in conclusions with USN reports or some other Corsair pilots.
So I think, his opinion on Corsair's performances for air combat seems can be doubtable.
Or FAA Corsair's clipped wingtip provided something actually lower performance.
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for case of AU-1, it was stated in USN document as day ground support attack airplane and used by marines, high maneuverability and handling chracteristic for carrier operation was not required for this variant.
It had x10 bomb racks of each 500 lbs capacity on the wings and additional armor plates on front fuselage bottom, so approx 1000 lbs heavier than World War 2 variants and CG position moved forward.
Of course, directional stability much weaker and stick force higher.
for example, according to USN report, It has been stated that the directional stability of the F4U-1 was much weaker with approx 1000 lbs extra weight on front fuselage bottom, AU-1 was always in that state.
And NACA report showed that forwarding CG position brings higher stick force.
I agree with Brown's opinion on AU-1, but it was not a suitable aircraft to evaluate Corsair's flight performance.
So this is why I was wondering about his evaluation for other later variants of Corsair.
During in World War II, Corsair's production inspection trials report stated both stalling and landing chracteristics were considered satisfactory with stall strip for late production models.
It's regrettable that there is no Brown's evaluation of that.