Acceleration comparisons

[horseback]

The document above states: "Rudder trim effectiveness was not sufficient to trim in the high power climb." If I get this correctly it means though FULL rudder trim was applied in a high power climb the plane still deviated from flying straight. So at least early F6F-3s were trim hogs in rudder when climbing with full power - and I doubt that later model F6F behaved much different - even if a larger trim tab or different rudder were added, changing from clevel flight to climb would still require lots of trim change in rudder.

If you read my post containing the trim sections from America's Hundred Thousand, you'll recognize the passage below:

"There were nose up trim changes with gear and flap retraction, though they were minimal, and the same was true of initial acceleration into climb. In general, there were substantial both directionally and laterally with speed and power changes, but tab action allowed trimming out control forces to zero except for the rudder. At low speed and high power rudder pedal force could not be trimmed out fully. Most pilots thought trimmability was generally good, though some made the following comments ‘Lack of trimmability”, Excess rudder trim change”, and “Aircraft requires excessive trim” (three pilots). It was noted that in a dive control forces could not be trimmed out quickly enough."

Trim adjustment was a relatively new practice in military aviation in the early 1940s, and most American fighters appear to have had some points in their performance where full trim input did not completely wash out the need for a bit of rudder input, or where it couldn't be input as quickly as the demand increased. The extra amount of right rudder needed didn't result in the unbalanced muscular deformities claimed by long-time P-40 or Bf 109 drivers, so it wasn't a severe problem, but it was something that wasn't supposed to be there, according to either the original request for proposal or the resulting contract language for the F6F-1.

The phraseology used sounds like a standardized bullet point in the test documentation to my long time government contracting ears; I would expect that that phrase, or some minor variation of it is found in almost every Hellcat acceptance test document. Without it in there, a battalion of government bureaucrats would have had a near fatal case of the vapors, and the US war effort might have ground to a complete halt.

As I pointed out, the FW 190A and Bf 109 lacked any in-flight trimming capability for their rudders, even though rudder had to be added or subtracted as attitudes and speeds changed; does that mean that they were 'trim-hogs' in the rudder department too? I know that US pilots doing comparison tests of German aircraft were quick to criticize that particular feature of those aircraft, but that it didn't seem to limit their combat effectiveness.

So it was with the Hellcat.

I'll try using the second stage of supercharger with the Hellcats and Corsairs as you suggested; if the results are significantly better with the initial test runs, I'll revise the charts.

cheers

horseback