Spit/109 sea level speed comparisons in 1.08 beta patch

[IvanK]

Firstly if you think WWII fighter pilots were going to engage in modern energy theory concepts such as sustained optimum energy speed turn fights you are deluding yourselves. Concepts of Energy bleed Ps rates where not really in the the WWII fighter pilots thought process. Zoom and Boom or general turn fighting was. A spitfire pilots mindset was "I can outturn this 109'. The 109 pilots mindset was "I better be careful and not try to turn with this Spit"

The argument about the (debatable) slightly faster level speed of the 109 over the Spitfire means the 109 must have better sustained turn performance at these speeds is bogus imo. If you accept that for a given flight condition the 109 is faster so therefore has superior energy (Ps) than the Spit so therefore can transform this into turn performance advantage think about this. The superior energy (Ps) is only in 1G flight. As soon as you load the airframe up who has the lesser energy rate loss now ? .... i.e. energy bleed ? Ps at 1G and Ps at say 4G are totally different things ... JTD says it quite clearly and even provides some numbers :

"It's in the physics. If you look (very closely in well hidden places) at the turn calc spreadsheet I attached the other day, you can see that near each planes top speed, the 109 gains ~1.1 °/s turn rate for every m/s of speed given up, while the Spitfire gains about ~1.5 °/s turn rate for every m/s given up. This means in example, for a 9°/s turn rate the 109 loses ~29 km/h, while the Spitfire loses ~22 km/h and has thus narrowed the gap by ~7 km/h. It's a trend that continues until at low speeds the Spitfire becomes superior."

So once the G comes on the 109 is losing airspeed faster than the Spit..... and we know where the fight is going now don't we? 1G Ps and Ps under G are not the same thing.

Thats why JTD says (and is correct imo):

"It really sums up to that the 109's biggest advantage is in flying straight and level, it will remain competitive throughout the high & medium speed range, with the advantage always decreasing. All this, mind you, at sea level against a 6.25lb boosted Spitfire I, which is as good as it gets for the 109. "

Then we have this strange concept of the faster 109 being able to turn better than the Spit at say 400Kmh so therefore he can deny a Spit (at less than 400kmh) closing to a Guns shot ! Its an axiom of Defensive BFM that if you just keep turning a slower aircraft can simply arc inside your turn nose in lead and close to guns. Robbo puts it quite eloquently:

"But it is also possible to cut the corner of the 109 and shoot at it alright at lead curve, then ease up the turn and repeat. All depends on the trajectory, the planes will obviously turn on different circles etc. If you make a deal that the 109 won't climb or scissor, just turn, you will win. Because the Spitfire is much better TnB fighter than Emil. Emil is decent turner, too, very maneuvrable and agile, but as for the sustained turn competition in actual dogfight, Spitfire has got better qualities. "

Kurfurst
"Just explain how a plane with less or no excess thrust can pull a sustained turn better than a plane with more excess thrust, thank you"....

I'll have a go or comment at least We are talking about 2 aeroplanes one with marginally better 1G Ps at lets say 400kmh. As soon as the 109 starts to turn how much of this Ps superiority does he now have ? If his -Ve Ps under G is less than the Spit then fair enough but is it ? JTD's figure show the 109 -ve Ps under G to be worse than the Spit.

The RAE Fan charts (accepted that a couple of people here contest these) show this quite clearly.