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-   -   Spit/109 sea level speed comparisons in 1.08 beta patch (http://forum.fulqrumpublishing.com/showthread.php?t=34115)

NZtyphoon 09-22-2012 12:57 AM

There's some info on the 109 slats here http://109lair.hobbyvista.com/index1024.htm apparently the Fs still used the swing arm assembly of the E to actuate the slats, while the G series used a simplified roller track.

Crumpp 09-22-2012 02:38 AM

Quote:

Just further weight to the fact handley page style slats open with force under load.


If you pull hard they will open with a loud bang but you don't even feel it on the stick.

You feel it most when you slowly change angle of attack.

Dami55an 09-22-2012 03:26 AM

The graphs having different scales makes it very hard to compare
http://www.gqth.info/0.jpghttp://www.gqth.info/7.jpghttp://www.gqth.info/8.jpghttp://www.gqth.info/9.jpghttp://www.ymeu.info/test5.jpg

Crumpp 09-22-2012 04:57 AM

Which Graphs?

JtD 09-22-2012 07:44 AM

What is the input data for your calculation?
- clmax (or stall speeds used + source)
- cdo (or power output, boost, rpm and speed + source)
- weight (source)
- assumed wing efficiency
- assumed prop efficiency

I would think the relation is about OK, but both planes are turning too fast and I also think that the high speed relation is a bit off.

SlipBall 09-22-2012 07:49 AM

Crumpp..Nice barn! but too small:-P

Crumpp 09-22-2012 01:13 PM

Quote:

Slipball says
Crumpp..Nice barn! but too small
LOL, Yes it is and now I need a bigger one!

Quote:

NzTyphoon says:

they have everything to do with WW2 military aviation
I don't have everything to do with WWII Aviation Nztyphoon.

Never claimed too but I do sit on the Board of Directors for a warbird restoration company.

Try spending a month looking for a waffengeber for a month and see if you don't learn something.

Quote:

JtD says:
both planes are turning too fast and I also think that the high speed relation is a bit off.
The airplanes are at sea level. Of course they are turning too fast....

Density effects will increase velocity, widen the radius, and increase the rate of turn. The engine power will also change with supercharger characteristics.

As for the high speed relation, anytime the aircraft has more excess thrust it will have a better turn rate as it can sustain more angle of bank at velocity.

The relationship is correct.

SlipBall 09-22-2012 02:20 PM

Quote:

Originally Posted by Crumpp (Post 462942)
LOL, Yes it is and now I need a bigger one!


Considering the shape of the building and the powers of Google earth, it's for the best that you removed it.

JtD 09-22-2012 02:43 PM

Quote:

Originally Posted by Crumpp (Post 462942)
The airplanes are at sea level. Of course they are turning too fast....

Planes at sea level still turn as physics determine, not "of course too fast". If you posted your input data as requested, I could easily check if there's anything I'd disagree with.
Quote:

As for the high speed relation, anytime the aircraft has more excess thrust it will have a better turn rate as it can sustain more angle of bank at velocity.

The relationship is correct.
I could easily see that if you posted requested input data. The way it looks from here, you chose 285 mph for the Spitfire and 500 km/h for the 109 - which leaves me to wonder: Do you know of a lower sea level top speed for the Spitfire and do you know of a higher sea level top speed for the 109? Just asking, because I don't.

Crumpp 09-22-2012 03:21 PM

Quote:

Planes at sea level still turn as physics determine
Yes they do and the formula's are all standard BGS for calculating aircraft performance.

They are same ones found in Perkins & Hage, Aerodynamics for Naval Aviators, Flight Mechanics, and Flight Theory and Aerodynamics.

You can argue with the authors of these books....

http://www.amazon.com/Mechanics-Flig.../dp/0470539755

http://www.amazon.com/Flight-Theory-...d+aerodynamics

http://www.amazon.com/Airplane-Perfo...ty+and+control

http://www.amazon.com/Aerodynamics-N...naval+aviators

The formulas are correct and the performance agrees with generic turn performance charts used in aircraft flight planning.

Input the correct parameters for wing area, power, aspect ratio, CLmax, and the formulas produce the results.

It is that simple.


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