Quote:
Originally Posted by majorfailure
I'll ask again, how else do you think the wing can generate the same lift at a higher speed (e. g. plane stays level), else than decreasing AoA?
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First of all, I meant it as a matter of degree; there has to be a reasonable limit of movement down as a result of the direction of thrust and limiting action of the elevator. I don't buy into the notion of an aircraft like the Thunderbolt wallowing with its nose up in the air at the speeds it travels when it enters the landing circuit or in economy cruise. It is simply exaggerated, and again, appears to be limited to that same group of fighters that there is the greatest amount of data and modern pilot reports about. We are talking about relatively straight, high lift wings across a fairly limited (by modern standards) range of speeds. We aren't talking about swept-wing jets here.
The Soviet aircraft all have a 'drop' of around a quarter of the WW gunsight circle's diameter, and it generally takes place between 370 to 400 kph ias, varying somewhat from Yak to LaGG to La. It also appears that the drop is not as great when the aircraft is in a constant speed compared to when it accelerates and that some aircraft have little or no 'drop' with acceleration or greater speed in general.
My impression so far is that aircraft like the Lightning, Corsair, Hellcat and P-47 have much greater 'drops' and that at certain speeds the nose will suddenly rise again somewhat at higher speeds. I haven't fully quantified it yet (as I have said, it takes about 45 minutes to actually make a 4 run track and at least the same amount of time to replay it and transcribe the raw data) but I think that these aircraft's noses raise and lower (and sometimes raise again) by nearly the full diameter of the WW gunsight circle, possibly more. At 100m, that puts the 'pipper' well below the horizon, while the Soviet fighters' gunsight center is just a bit above it (and at considerably higher speeds in many cases).
I contend that it is way too much variation, and plan to create a separate thread about it, but only once I have my ducks in a row. Right now I'm struggling to maintain level flight and have noticed that my key visual references are either unreliable in the case of my cockpit instrument displays or are changing on me in the case of the view of the horizon, which I could normally 'set' at a certain point in my cockpit framing to keep level. I need to (a) fly a reasonably level course while accelerating through the speed range and (b) take a series of screen shots from the track after doing so to confirm what are so far just impressions.
If I'm wrong I will say so; it won't be the first time.
cheers
horseback