Higher Speed Sustained Turn Performance Testing

[Stoney]

Anyone have an in-game data for sustained turns at higher than min radius?  For example, what's the tightest turning aircraft at 300 mph IAS sustained?  Or, is this type of data to complex to accurately test?

[MOSQ]

At 300 mph you would constrained by the 6G blackout, not the turn ability of the aircraft. I think all our fighters can pull 6 G's at 300 mph.

[Stoney]

At 300 mph you would constrained by the 6G blackout, not the turn ability of the aircraft. I think all our fighters can pull 6 G's at 300 mph.

No plane in the game is going to sustain 6G at 300 mph, or am I wrong?

[MOSQ]

Correct. I'd have to go thru a bunch of Badboy's Energy Diagrams, but I'm pretty sure next to no planes here can maintain more than 3.5G's sustained at 300mph.

The question is, does it really matter? If you are in front of me and pulling 3g's sustained at 300MPH, I will just pull 4G's and pull inside you. I will lose some speed, but if I'm in firing range I will shoot you. If I'm not in firing range and slower than you, you don't need to turn. If I'm not in firing range and faster than you, I will pull the same 3Gs, catch up, pull 4 gs, and shoot you down.

So as you see me turning inside you with a firing solution, you pull harder, I pull harder, until we reach 6 g's blackout. 

[bozon]

Correct. I'd have to go thru a bunch of Badboy's Energy Diagrams, but I'm pretty sure next to no planes here can maintain more than 3.5G's sustained at 300mph.

The question is, does it really matter? If you are in front of me and pulling 3g's sustained at 300MPH, I will just pull 4G's and pull inside you. I will lose some speed, but if I'm in firing range I will shoot you. If I'm not in firing range and slower than you, you don't need to turn. If I'm not in firing range and faster than you, I will pull the same 3Gs, catch up, pull 4 gs, and shoot you down.

So as you see me turning inside you with a firing solution, you pull harder, I pull harder, until we reach 6 g's blackout. 

If you are in front of me and start a 3G turn, I pull the same 3G turn and still get a lead shot at you.

[Badboy]

If you are in front of me and start a 3G turn, I pull the same 3G turn and still get a lead shot at you.

Yep, and you can still get enough lead for a shot with even less G.

I have a tool that I use to analyze pursuit curves (originally used to study missile evasive maneuvers in another life) and here is an example of a target aircraft doing a 6g (max) break turn and it shows the attacking aircraft tracking a shot and pulling more lead than required with only half as much G.



The down side, of course, is the inevitable flight path overshoot and subsequent reversal.

Badboy

[Badboy]

Anyone have an in-game data for sustained turns at higher than min radius?  For example, what's the tightest turning aircraft at 300 mph IAS sustained?  Or, is this type of data to complex to accurately test?

You can get the information you want from EM diagrams like the ones shown above that have a Ps=0 curves, because that curve shows you the sustained turn over the entire envelope from the stall to the top speed. You will notice in the example above that both aircraft have almost identical sustained turning ability at about 305mph where they can both sustain a turn at about 11 degrees per second.

Because the sustained G at top speed must drop to 1G, the sustained turning ability must drop off very rapidly at high speeds, as you can see above.

Hope that helps.

Badboy

[Stoney]

I wasn't necessarily asking with respect to ACM.  There have been numerous threads or posts in threads that discussed high-speed turning abilities of aircraft that were based on anecdotal evidence.  Widewings infamous graphic that shows the P-51 second only to the Spitfire being the most oft-used, if misunderstood example.

There may be some mechanics I'm missing here, but I suppose I'm asking about 1G, sustained turn performance, and I don't think that relates to the energy diagrams.  I guess the next question is why would it matter, and I'm not sure to be honest.  It was simply a theory that I have but don't necessarily have either data or the expertise to follow it through to QED.

[Widewing]

I wasn't necessarily asking with respect to ACM.  There have been numerous threads or posts in threads that discussed high-speed turning abilities of aircraft that were based on anecdotal evidence.  Widewings infamous graphic that shows the P-51 second only to the Spitfire being the most oft-used, if misunderstood example.

There may be some mechanics I'm missing here, but I suppose I'm asking about 1G, sustained turn performance, and I don't think that relates to the energy diagrams.  I guess the next question is why would it matter, and I'm not sure to be honest.  It was simply a theory that I have but don't necessarily have either data or the expertise to follow it through to QED.

It's not my graphic. It comes from a piece written by former O.C. Flying at the Air Fighter Development Unit, Sqdn. Ldr. T.S. Wade. I assume the gentleman was in position to judge.




My regards,

Widewing

[Badboy]

There may be some mechanics I'm missing here, but I suppose I'm asking about 1G, sustained turn performance, and I don't think that relates to the energy diagrams.

You can't sustain a level turn at all at 1G, you would just fly in a straight line. However, 1G is shown on those EM diagrams, it is the base line, where you can read off the 1g stall speed, and the top speed.

Hope that helps.

Badboy

[Stoney]

It's not my graphic. It comes from a piece written by former O.C. Flying at the Air Fighter Development Unit, Sqdn. Ldr. T.S. Wade. I assume the gentleman was in position to judge.

Sorry, didn't mean to imply you created it.  You were the original poster AFAIK.  Also, didn't mean to disparage the graphic...Merely stating that some on these forums have used it out of context.

[Stoney]

You can't sustain a level turn at all at 1G, you would just fly in a straight line. However, 1G is shown on those EM diagrams, it is the base line, where you can read off the 1g stall speed, and the top speed.

Ahhh, yes  .  Told ya I was missing something   Perhaps I should have used "low-G" or "less than 2G" as the qualifier.

[bozon]

I think it is important to note that the smallest sustained turning circle is not achieved with a very low speed, but almost at the same speed of best sustained turn rate. The spits minimum-radius velocity is slightly higher than 150 and is about 160 for the yak, at almost 3G (~70 degree bank angle).

Wallowing at 100 mph may seem like the smallest circle, but it isn't.