Hi Haa,
great to see you've completed another series of tests!
As in any experiments, the data points you've measured display a small random error, so I'd suggest to create an average graph eliminating these errors by averaging each data points v^2/n value and using it as the basis for the corrected graph.
It could look like the one I recently prepared:
Here's another graph from the same set of data, preseting the results in a way that's better suited for discussion:
As you can see, I've plotted maximum G rate over speed directly, using the average from your measurements. For sake of the illustration, I've assumed 9 G to be the structurally permissable maximum load.
Additionally, I've made up the term "orthogonal turn rate" for the turn rate that can be achieved without caring to keep the turn level, i. e. when pulling into a turn from a 90 degree bank, and to hell with gravity! ;-)
What does this graph tell us? Corner speed coincides with the lowest speed at which the maximum G rate can be achieved. No surprise here!
We also see that corner speed is very close to level maximum speed, which is one reason not to spend too much energy memorizing corner speeds. A high-performance turn at corner speed will eat up energy so quickly that speed will drop anyway, and since the turn rate slope is quite similar on both sides of corner speed, you'll simply want to go as fast as possible to get the best possible turn rate for the longest time.
Jets are so much faster that they can be very far beyond corner speed, suffering a serious manoeuvrability penalty, but in propeller fighters, this is usually not a concern.
Keep in mind that the speed is indicated airspeed, and the graphs are for low altitude. At greater altitudes, your top speed will be an even lower indicated airspeed, so that you'll be operating below corner in most cases anyway.
Another feature of our graphs is that the orthogonal turn rate grows linearly with speed (up to corner speed, of course). This may seem surprising at first, but with centripetal acceleration a ~ v^2 and turn radius r ~ v^2/a => r ~ a/a = const, we arrive at a constant turn radius regardless of speed. If you're going along a constant radius, any increase in speed will obviously result in a linear increase in turn rate, too.
If you know 1 G stall speed and the permissable maximum G rate of an aircraft, you have enough data to draw such a diagram for the aircraft in question. There's not that much to learn from it, since the aircraft with the lower 1 G stall speed will inevitably have a higher (or at least equal) turn rate anywhere in the diagram. Only if it suffers from a lower permissable maximum G rate it might fall off in the high-speed range, but I think the limits of all WW2 fighters were pretty similar.
Of course, if you add energy data, the diagram will become more interesting again :-)
Regards,
Henning (HoHun)
