Quote:
Originally Posted by gaunt1
Made another chart in Excel.
The P-40 and the FW-190 accelerates very poorly, is this realistic? Even more interesting, that the F4U-1A and the 109G2 have almost exactly the same acceleration!
I added some missing data from the earliest tests, like 350-400 or 400-450, its just guesswork, but it fits nicely. You can see the added numbers if you drag the chart away, I highlighted them in red.
|
The Focke-Wulf's acceleration is a problem for me too, but it may just be the altitude being too near the supercharger's shift point; the first one I tested was the A-5 (1.62 ata) version, and it's
supposed to be optimized for fighter use (probably at a higher altitude band). I just finished testing a 'plain vanilla' A-5 without WEP, and the numbers for it were somewhat better, to the point that it achieved between 480 and 490 kph IAS in level flight, or not quite 600 kph TAS at 3050-3130m.
I've started to notice that most of these aircraft have a range of speeds where they accelerate best, where the engine has overcome the initial weight and inertia to the point that a climb of 30 meters (that's over 60 feet, or the height of a four or five story building) seems not to affect the pace of acceleration much, if at all. Of course these are generally periods of six seconds or less, but if you or I were sitting in the cockpit of the real thing, we're going to
feel that, and it's going to be like a really good roller coaster (or a really bad one, if your harness isn't snug). In any case, it's kind of hard to extrapolate or predict those bands. Some are at lower speeds and some are a good bit higher. I will try to highlight these later.
With the exception of the water-injected Corsair, though, radial powered aircraft are usually more sluggish in the initial lower ranges.
As they reach the upper ends of the acceleration tests where the drag has built up and the engine is starting to overheat, the slightest incline or decline is critical. Here the test is to see if it can maintain a speed in level flight for several seconds; if it can't, I will not count it.
The P-40 is a big, heavy and relatively draggy airplane; if you build scale models, it becomes readily apparent when you place the US fighters of WWII next to German, Soviet or early Japanese fighters of the same scale. The P-40 is gigantic next to a FW 190A, and it just looks
lumpy. Next to a P-51A, it's the same size, but it seems even more lumpy and crude, and the P-51A outperformed it at every height and measurement, from climb to acceleration to top speed; everyone agrees that the P-40 could turn a tighter circle, but any version of the real life P-51 was much less work for the pilot and easier to keep under control. Therefore if the pilot of the P-51 is as skilled as the P-40's pilot there would be no doubt about the outcome of a dogfight. It took a supremely skilled pilot to beat a merely good pilot in a P-51 or P-51A, and it took a supremely good and
lucky P-40 pilot to beat an experienced Merlin P-51 driver.
Which brings me to something that has become a critical factor in these tests: trim response and the accuracy/clarity of the instrument panel. Some aircraft I have tested are like driving a very well made car on a smooth road; you push the throttle and Prop Pitch forward and just go. There may be a little twist as the increased torque kicks in, but this is easily corrected, and you can compensate with rudder and hold the stick forward while you add trim, but it's all very smooth. The wings don't wobble back and forth like you're balancing on the head of a pin, the climb indicator doesn't bounce back and forth, the needle and ball are quick and accurate, the artificial horizon is easily interpreted for maintaining level flight, and they are all easy to see.
The Ki-61 is an excellent example of what I'm describing here; the panel is well-laid out and the instruments are clear at my preferred Wide View setting and they are accurate. At the same time, the aircraft's FM itself is very predictable and smooth--it's not blazingly fast, but it is easier to keep straight and level at all speeds than the Macchi C.202 or the Bf 109E, and it gives better test results in part because of this quality. I never varied more than 12m from one interval from the next, which is vastly better than even much slower aircraft I have tested. It just responds beautifully to your commands, and I would expect it to be easier to keep on target because you're not fighting your stick and rudder all the time. The Ki-43 is similar, as is the P-38 (although the Lightning's instruments are on the tiny & fuzzy side in Wide View--you have to go with Normal View to see what's going on there).
By contrast, the much faster FW is a pain to test because the instruments are literally out of focus in Wide View, they are still hard to read in Normal view, and the climb indicator is simply
deceptive; a tiny (one division, which should mean something like 100m per minute) deflection up or down can result in a climb of 150m in less than 5 seconds. The combination Turn & bank/Artificial Horizon is next to useless because the little 'airplane' disappears into the horizon line, unless you're in Gunsight view, the needle barely moves (ever!) and the ball is again, out of focus in Wide View, and really not much better in Normal View. Add to that the tendency for the FW to outrun its elevator trim, which has you shoving the stick three quarters of the way forward, while you simultaneously struggle with the head-of-a-pin wing leveling exercise...and finally, once you do get trimmed for almost level flight, the aircraft will consistently swoop upwards or downwards without warning as it reaches certain specific speeds.
When you're watching the track in Wonder Woman view, trying to concentrate on the speed changes, it looks like you are constantly jerking up and down, left and then right; a real-life pilot would be bruised and sore everywhere his harness touched him after only a couple of runs.
To be fair, the FW's cockpit animation dates back to the original Il-2 Sturmovik game that I bought in March of 2002, so it is quite dated, and the original equipment may actually have been that vague, because the pilot had a full range of vision, his inner ear and the pressure on the seat of his pants to augment what the instruments told him. This was the heyday of Visual Flight Rules, the era when IFR usually meant "I Follow Railroads", so yeah, I get that reasoning. However, in a flight simulation that doesn't provide 180 degree fields of vision or attitude changes to the virtual pilot's chair, uniform clarity and accuracy for all aircraft's instruments would seem a desirable thing.
Still distilling the data from my last series of tests. CW-21B, A6M2, Ki-61, Macchi C.202, plain FW 190A-5 and reruns of the 1A Corsair and the F6F-3 to my current data standards.
cheers
horseback