Quote:
Originally Posted by Woke Up Dead
There's still merit in doing it "by hand" though, Horseback made a lot of useful observations about the difficulty of trimming some planes as they accelerate. I am curious about how much difference trim makes though, maybe someone familiar with that tool could set up a similar test for a couple of the planes that Horseback thought were hard to trim to see how much better the results are.
It's not about better results ( good pilot will do as good as AP), it's about consistency and ease of testing. And trimming issues are highly exaggerated, you can make good runs without messing with trim much, even in "hard to trim" planes. Just make a plane nose heavy before you start your run and you will not have any problem in making smooth run with minimal altitude deviation.
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The trimming issues are generally pretty specific to a given aircraft and seem to be not just a matter of adding nose down trim; certain aircraft will consistently raise or drop their noses
abruptly at certain speeds after an extended period of acceleration in level flight, even when you try it flying in the Wonder Woman view (which is the only view option that actually provides consistently accurate and timely climb/altitude and trim data). If you do your runs 'in the cockpit' as I do, shifts in AOA as speed changes make using outside reference points (like the horizon) impractical, and dishonest, inconsistent, illegible or slow Turn & Bank indicators, variometers, altitude indicators and artificial horizons make certain
specific aircraft extremely difficult to keep level, when added to their trimming problems. Certain other aircraft of similar performance seem to need much less adjustment and have either consistent or particularly accurate in-cockpit instrument displays, some of them in direct contradiction to reports of the period.
In my opinion, many of the 'hard to trim' class seem to be hypersensitive to minor stick inputs as speed increases; I use the same low stick sensitivities for all aircraft testing, as well as 50% filtering, and attempting to maintain level flight in the 'hard to trim' group with the stick and pedals is just as difficult as trying to add or subtract elevator and rudder trim with button or axis inputs, and sometimes worse.
Quote:
Originally Posted by horseback
The whole point of this exercise is to do it by hand; if the average player cannot duplicate the results of the tests without a ton of specialized controllers, or be able to overcome some of the problems inherent in flying a given aircraft without many, many hours of practice, meeting the 'book' numbers is meaningless.
"Book" numbers are not what average pilots could do, they are what highly trained test pilots could do.
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Test pilots of the 1930s and WWII era were largely self-taught; actual 'training' and schools for test piloting came much later. Military training required a higher standard of precision than general aviation because the military required a level of teamwork and predictability between aircraft un-needed in civilian aviation. Generally, military testing showed much less optimistic results than the manufacturers' in-house tests in the 1930s and early 1940s.
Regardless, the "Book" numbers are a basis of comparison for the average pilots; if plane a can accelerate from 270 to 450 kph in under 40 seconds and plane b takes almost a minute with the same pilot, their "book" numbers should be at least proportional. When other factors intrude
or are artificially injected, the proportional differences can get a little lopsided.
cheers
horseback