Why still no dive acceleration difference?

[mayshine]

Originally Posted by AndyJWest

rofl!

I am not native speaker, but i am trying to solve something

the point is to express

you'd better continue to wish I am baned

by the way

can you speak Chinese well?

[AndyJWest]

can you speak Chinese well?

No. But you are trying to communicate in English - and failing.

[mayshine]

Originally Posted by AndyJWest

No. But you are trying to communicate in English - and failing.

sounds u r happy to find this

instead of finding some truth

[JtD]

mayshine, I've recommended you to do this test:

Take a Fw 190A-9 and a Spitfire IX 25lb, start at 550 km/h at 1.5km altitude and dive them to a place 15 km away. Check their speeds.

Have you done it?

I can also assure you that the issue has been brought up again and again over the years and that il-2 is fairly accurate at typical combat speeds. The limitations will be reached only when you reach very high speeds, where the effects of near sonic flight are not as strong as they are in real life.

[mayshine]

Originally Posted by JtD

mayshine, I've recommended you to do this test:Have you done it?

I can also assure you that the issue has been brought up again and again over the years and that il-2 is fairly accurate at typical combat speeds. The limitations will be reached only when you reach very high speeds, where the effects of near sonic flight are not as strong as they are in real life.

I fairly know this, I start Il2 by 2004,

of cause spit will lag behind when it is closing to it's limit and start shaking

but

what I want to propose is fast and verticle dive

a intensive speed increasing dive, u sure they will perform in the same way?

obviously 15Km is not a steep dive

[mayshine]

by the way

even one man I knew who knows Oleg and now part of paticipation of the "world of Plane"

he doubt the steep dive in IL2

[JtD]

In terms of physics:

dive acceleration = earth gravitational constant + excess thrust / mass

It is easy to see that as long as excess thrust is larger than zero, mass will reduce the planes acceleration. Excess thrust will be less than zero when the plane is above level speed for that power setting. Also, in typical flying conditions, earth gravitational constant >> excess thrust / mass, so excess thrust / mass doesn't really matter.

If you don't care about physics, at least search for the TAIC test FC99 mentioned, read it, and adjust your expectations. That time would be a lot better spend than making another dozen posts on the issue here.

[mayshine]

Originally Posted by JtD

In terms of physics:

dive acceleration = earth gravitational constant + excess thrust / mass

It is easy to see that as long as excess thrust is larger than zero, mass will reduce the planes acceleration. Excess thrust will be less than zero when the plane is above level speed for that power setting. Also, in typical flying conditions, earth gravitational constant >> excess thrust / mass, so excess thrust / mass doesn't really matter.

If you don't care about physics, at least search for the TAIC test FC99 mentioned, read it, and adjust your expectations. That time would be a lot better spend than making another dozen posts on the issue here.

Good , finnally I found some one who pose the formular

but I want to correct u in some point

G actually the advantage to heavy planes

see my formular posed previously.

F= ma, a=(m*g - back force)/m

when the backward force become larger and larger

the mass * G will become more and more helpful to speed up the plane.

that means the plane will bigger mass and less back force will be faster

and the back force is complicate,

it is regarded to the strenght of the plane, air wave darg force, pro pitch
propeller tip speed, the shape of the wing, wing load and so on

I dare not to simplify all this in to a univeral A = 8.7m/s as I calculated
previously

Do you still think I do not know physics?

[mayshine]

to make it more obvious

set g=10, m = 10 , back force = 50

first plane mass = 2m
second plane mass = 1m

F=ma

a1: a2
= (2m*g-backforce)/2m : (m*g-backforce)/m
=150/20:50/10
=7.5:5

a1 is 50% faster

[FC99]

So in this extreme case plane have 2,5m/s advantage in acceleration. What will be the difference in distance after 12-13 seconds?

And in the end try with different values for drag for each plane like it is in most real life cases.