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View Full Version : Nice Spitfire videos!

Richardsen
06-24-2007, 03:58 PM

look 02:20 into the video. That turn looks quite tight...

Ray Hanna in MH434

Flying Legends 2006

Spitfire PR XI

BBMF MK II One of the nicest handling Spitfire flying today!

Taylortony
06-24-2007, 04:52 PM
Cool, thank you

GBrutus
06-24-2007, 05:06 PM
Great vids, thanks! PL965 is my favourite Spitfire, such a beautiful aeroplane. http://forums.ubi.com/images/smilies/inlove.gif

skarden
06-25-2007, 05:51 AM
damm that IS tight http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif http://forums.ubi.com/images/smilies/59.gif

cool vids cheers http://forums.ubi.com/images/smilies/25.gif

Viper2005_
06-25-2007, 07:17 AM
damm that IS tight

Well, let's perform some calculations. It's not quite a Ps=0 level turn, but probably close enough for government work since the turn finishes in pretty much the same place that it started, and at what looks like the same speed.

It takes 20 seconds to go through 360º.

The bank angle is nearly constant. I took a screen capture & measured it at 73º.

Now, using the level flight assumption, that means that the aircraft is pulling 3.42 g.

Therefore the horizontal force component is 3.28 g.

Via some sneaky manipulation of the variables*, I have it that:

t*a^0.5/2pi = r^0.5

thus

r = (t*a^0.5/2pi)^2

This is where the SI is so wonderful!

3.28 g ~ 32.2 m/s^2.

therefore r = 326 m (0 dp).

Since v = (ar)^0.5,

v = 102.42 m/s which is:

368 km/h
229 mph
199 knots

This is of course just back of an envelope stuff. But it seems reasonable enough.

Indeed, it is extremely satisfying to note the excellent agreement between these calculations and the latest version of IL2C, which gives a turn time of just over 20 seconds at 1 km and 370 km/h for the LFIXc (full wing).

* I used a = v^2/r and t = 2pi*r/v as my starting point and then substituted. It all looks rather nasty, but is saved at the last minute by the fact that r/r^0.5 simplifies to r^0.5.

mauld
06-25-2007, 10:58 AM
I have one of the Mk IIa here