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KenobiOrder

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  1. No it does not. I am looking at it right now in two separate documents. It specifically states that maintaining datalink has no affect on missile Pk after the missile goes Pitbull UNLESS the missile loses track.
  2. That is not correct. The manuals all state the the data link improves Pk in situations where the missile loses track. Reference the HAF-34 for the F-16 for example.
  3. Wing rock is a stall condition. It generally occurs because one wing stalls first, then the other, and then oscillates. In any case the US manual mentions no wing rock whatsoever until you get below something like 250kph, at which point it reports +-50 degree wing rock. The only pre-stall condition reported is buffet, which itself only occurs in certain conditions. As can be clearly see in the stall diagram, on both Russian and American documents, the only warning is for buffet. There is no wing rock warning on the chart, and no mention of it at higher speeds in the expanded description that I could find. What can also be seen in that the 28 and 33 degree limits are NOT the stall limits, unlike in DCS Mig-21. The instructions call the 33 degee limit the stall limit, but thats contradictory to the chart....except at high mach numbers. I sort of get the impression that the 33 degree limit is placarded as a safety limit because the stall AoA appears to decrease substantially with mach number. nullnullnullnullnullnull
  4. Yes that's for the airfoil, not the entire wing. If you reference the chart from the U.S manual it shows the actual stall at a much higher aoa than 33 indicated. There is no mention of wing rock except at speeds at 250kph and below, making me wonder if the dcs mig 21 is modeled backwards by accident.
  5. The original main point was simply that the explanation given by the developer was not correct, as F2 view does not show pitch angle. It shows true AoA. The reason that the stalling AoA of 15-16 is wrong is because a delta of the Mig's type does not stall anywhere close to this. It simply does not. The issue with the landing AoA being off assumes either 1:1 or that the error relationship should be linear. The error of the wing mounted gauge in the test was not linear. Landing angles of attack vs read out on the UUA could be much smaller. Although it isnt obvious to me why one would land at critical angle of attack. In fact what might be wrong here is that the relationship in the game does in fact seem linear, as it appears to be two to one at all angles of attack.
  6. Except its not by a factor of two. Not sure why you bothered pointing out that they are different planes, since I already stated that. But since you want to use the Mig-23 error equations as an example, I am simply continuing that example. And they do not show the AoA being off by a factor of two. Those error equations yield errors of about 40%. If you plug them into the Mig-21, you get stall angles of attack of around 20 degrees. And no, the planes stalls when it hits 33 degrees in game, except at very very very low speeds. The stall wing rock is clearly some kind of scripted behavior. It also doesn't make sense that the critical AoA changes based on speed, because that is not how wings work.
  7. Except the issue at hand isn't whether there is an error. It's how big the error is. The current in game error is greater than twice the true aoa. None of the evidence provided suggests that this is accurate. Both the paper you linked and the comparison to the mig23 yield much lower discrepancies than we have in game. The mig23 isn't the same plane, but continuing your comparison, that error equation only suggests that the amount of error in the sim is excessive. Using the indicated stall of 33 degrees, it would give a true aoa of between 19-and 21.25. Which would be a much more reasonable stall aoa for a delta swept at 57 degrees.
  8. It is a wild assumption that the discrepancy between the indicator and the true angle of attack is a factor of two. And it flies in the face of what is known about delta wings of the type fitted to the mig. And that is what it matters. Because as far as the flight model acccuracy is concerned, it does not matter at what reading the indicator is at when the jet stalls. What matters is what true angle of attack the indicator corresponds to when it reads "33 degrees"
  9. This doesn't matter at all if that relationship is wrong. Which it is. The actual AoA of the wing is half what the UUA is showing. Let me put this very simply: Delta Wings of the Mig-21 type do not stall at 15 degrees. You can talk all day about what you think the developer meant by local AoA. It doesnt matter. The thing that matters is that the UUA's relationship with the real AoA is wrong, because it cannot be right if it is reaching the 33 degree position in tandem with the wing hitting the true AoA at 15 degrees.
  10. This presumes that the UUA is off by a factor of two, and also that the game models this. I see no reason to make that assumption. The actual stall angle of attack should correspond to the AoA in the F2 view, and right now that is about 15 degrees. Delta wings do not stall at 15 degrees. 15 degrees critical AoA is what you would expect from a tapered straight wing, like on a P-51. Delta wings have a much lower slope of Cl/AoA, and they have lower max CL generally, but they dont critically stall at 15 degees. In any case, this is not what the developer stated is happening. They stated that the reason the UUA is different is because they claimed the F2 view is NOT the actual AoA, but is actually pitch angle. Which is why I posted the image at the beginning so everyone would at least theoretically be on the same page as to what that means. AoA is the angle between the flight path and the chord line, and the pitch angle is something else entirely that has nothing to do with fuselage airflow instrumentation errors.
  11. Right except what Frederf said sort of made zero sense. The chart shows a Cl increase from 1-1.4 depending on Mach number. And the claims that there would be no CL increase also seems to assume the 28 degree line and not the 33 degree line, which shows a larger and sooner increase, and is incidentally the number we car about because 33 degrees is where the chart says wing rock starts. In any case its not just the Cl increase that is important here. Its the ability to maneuver generally. The current jet hits a wall at about half the AoA it should, and this means flying it is a very bad experience where you cannot pull AoA as needed to fight.
  12. Right so you have no idea where I am coming from. I am pretty sure you think I have read that bull<profanity> paper regarding the supposed magical agility of the Mig-21 written by two guys whose names I cannot pronounce or remember. Except I am not. I don't think the jet should turn with modern planes, far from it. The 21 cannot even turn with the IRL F4, much less a F-16. Not sure where you got that from either aside from making wild irrational assumptions about my goal here. Making the jet stall at the correct critical AoA would not result in a magical turn fighter. It would only mean that we wouldn't get artificially stuck faffing about at 15 degrees of AoA when doing an unsustained turn. The Mig-21 doesnt have the thrust necessary, so while we would get to the proper AoA the sustained turn performance would still be worse than the current in game max sustained turn performance which is about 12-14 degrees a second. In game right now if you get below 400kph the wing rock magically goes away for some reason, and you can pull over 30 degrees of AoA as per the F2 view. But even with Emergency Burner, you are not going anywhere. Your stuck waffling about at 300kph, which is fine. The problem is we cannot generate reasonable levels of instantaneous turn performance due to the incorrect amount of AoA we pull. The mig-21 we have in game right now is stalling in a manner that is consistent with straight winged world war two prop planes, not a Delta wing.
  13. He referred to it that way because he was making a distinction between the pitch angle and the AoA, as per the image in my first post. He also states that the UUA readout is the local AoA and that is what is implemented in the FM code. The discrepancy is that he thinks the F2 view and tacview arent showing AoA, but pitch angle, which is not correct. Whatever angle he has coded is erroneous and is resulting in us stalling at about half the approximate value we should be. Regardless of what the Mig-21 base their angle on, deltas do not stall out at 15-16 degrees angle of attack like it is in game right now. Deltas have a lower slope than say a straight wing like a ww2 plane, but they generate a slightly lower Cl Max at a much higher max AoA. Whatever the true value of the AoA, our current stall is far too shallow.
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