Spit/109 sea level speed comparisons in 1.08 beta patch

[Crumpp]

First of all, 400kph is within the power stable region of the Bf-109's curves.

What does that mean? It requires ~350 hp to go from the stall point of 82 Knots to 215 Knots (400kph). That is a change of 133 Knots.

We are in a region that small power changes make for large changes in speed.

Compare that with the power required to go from 400 kph to Vmax in the Bf-109E3 is another ~545 hp to increase speed ~54 Knots.





How long will this take?

That too is easy to find out with some applied physics.


Acceleration = (Change in Velocity) divided by (Change in Time)

The average acceleration of the Bf-109E3 from 82 KEAS to 215 KEAS is ~9.6 fps^2.

We have to use the same units so our KEAS is converted to feet per second.

Rearranging our formula to solve for time:

Change in Time = Change in Velocity / Acceleration

delta t = (363fps - 138.4fps) / 9.6 fps^2

Feet cancel out as well as one of the second leaving us with the unit of seconds....

Change in Time = 23.3 seconds

Twenty three seconds from the stall point to the 215 Knots for the Bf-109E3.

Same conditions for the Spitfire:

Going from 82KEAS to 215KEAS, the Spitfire has an average acceleration of 8.4 fps.

delta t = (363fps - 138.4fps) / 8.4 fps^2

Change in time = 27 seconds

Now going from the stall point of 67 KEAS in the Spitfire, we see an average acceleration rate of 9.96 fps. This is because the Spitfire has more excess thrust at low velocity.

Considering that it would be a very stupid Bf-109E3 pilot to be slow flight in the vicinity of a Spitfire, the Bf-109E3 can maneuver quite well and dogfight the Spitfire.

The Bf-109 is pretty safe it if stays in its envelope and does not try to fly were it cannot.