Author Topic: the turn fight and why it kills  (Read 3815 times)

Offline boomerlu

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Re: the turn fight and why it kills
« Reply #60 on: February 04, 2010, 04:45:49 PM »
Probably the biggest point crutch missed is that these are WW2 fighter planes: they do not have enough power to sustain corner velocity turns, and definitely not enough power to increase IAS while turning max-G at corner velocity.

In the case of dueling over-powered jets who can still increase IAS while pulling a max-G turn, he would be right in the conclusion ASSUMING the increased power jet stays in the flat turn rather than using the energy to climb. Increasing power in this case would push IAS past corner velocity, reducing turn rate and increasing turn radius.
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Offline humble

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Re: the turn fight and why it kills
« Reply #61 on: February 04, 2010, 05:06:04 PM »
If I understand your second graph then this is true;

the 3G line intersects the Ps=0 line at about 270 or so.

If I reduce speed, all the way to stall speed at about 155, while holding 3 Gs, I have excess energy to work with.

this energy, I can use to increase speed, pull more Gs or gain altitude (mainly by using top rudder to point the nose above the horizon), is this correct?

also the formula, I posted at the beginning is within rounding errors of the Gs/Speed/radius points on the graphs.

since there is no altitude component to the graphs, speed is probably IAS instead of TAS.

I'm sorry but your making no sense here at all. If you reduce speed to 155 while holding 3G's you have no excess energy. That is the maximum sustainable G load. If you pull more G's you'll scrub E...you can relax your G's and gain speed  at the expense of a wider turning circle and less DPS. Recognize that the plane at cornering speed not only has a slightly smaller turning circle but a significant advantage in turn rate picking up roughly a 1/3 of a circle per turn. So even though the faster plane can't sustain its corner velocity in a level turn he can either use a low to high yoyo to maintain extended pressure or he can commit his E advantage in an attempt to pull lead.

One of the biggest mistakes I'd see as a trainer was a concept of linear pursuit where the pilot attempts to fly tighter by reducing speed instead of using out of plane manuvering to increase speed closer to corner velocity. So if your at 270 the best thing to do is to pull G's in a high yoyo scrubbing down closer to best corner speed. The yoyo will give you angular advantage vs a flat turn & store E for future use. As you close to corner velocity you can then establish a rate of decent that will allow you to maintain corner velocity a few seconds more without any net loss of altitude.

So if we are in a flat turn in a neutral position (cockpit to cockpit) and you throttle back looking for a 3G 155 turn and I maintain full power put pull a climbing 6 G turn I will gain angles on the deceleration since I have a 10+ DPS edge as well as a smaller turning circle a majority of the time. Once I hit my corner speed I have alt, E a sustainable (for a period of time) advantage in both turn rate and DPS. I'd catch you in a few revolutions if not sooner...

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Offline Sonicblu

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Re: the turn fight and why it kills
« Reply #62 on: February 04, 2010, 08:36:58 PM »
thnks I understand better now.

Does it make sense to chop throtle to get to that cornering speed then push the throtle forward and hit wep to maintain it as long as possible.

I'm just trying to clear up some missconseptions I have. I must not be understanding what im doing in a circle fight to win it. I do deploy flaps as my speed drops and that seems to help.


Offline humble

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Re: the turn fight and why it kills
« Reply #63 on: February 04, 2010, 09:45:56 PM »
I don't have the ACM nuts and bolts that Mace,WW,Murdr,TC or Badboy do (sure I'm leaving a few out) but I've always encouraged out of plane maneuvering vs a reduction in speed when possible. I know i'm guilty of chopping throttle a lot more then I should at times. Basically what it tends to do is give you unsustainable lead at best. You chop to "gain" angles but then fall into -E lag...sometimes even before you actually can pull enough lead for even a brief shot window. By using a high yoyo and heavy G loading your using the "bent paper plate" illustration you always see as well as reducing speed and storing E...so if you get a 500 ft "pop up" will cutting to corner speed...you then can sustain corner speed for almost 4 seconds going down hill before you get back to your original alt. If we view that vs a bogie that countered with a chopped throttle high G turn...you'd both be pulling 6 G's early but he would fall thru corner speed faster and continue toward the 3 G mark...so assuming you were even in the 1st few seconds...you'd then have 4+ seconds with an advantage of 10+ DPS or more...continuing with the now low yoyo you'd eat up another 40+ degree's of arc. Your sustained turning circle at corner is just under 11 seconds (at 34 DPS) while his is over 15 seconds (at 23DPS)...so in those 8 seconds you'd have covered roughly 3/4 of a circle and be traveling at roughly 215 mph. The Bogey would cover just over 1/2 circle and would be traveling at 155 MPH.

As always any or all of the above please correct me if i'm stating this wrong....but in the end your better to decrease to corner via a high yoyo and then cash back in the E at the appropriate rate of decent to maintain your best cornering speed....

"The beauty of the second amendment is that it will not be needed until they try to take it."-Pres. Thomas Jefferson