PDA

View Full Version : MiG critical speed changes for different alt(?)



NorrisMcWhirter
03-12-2004, 06:35 AM
Hi,

Took the MiG3(shvak) up to 9k to follow a 109, the other day.

In a dive, the MiG3 managed about 800kmh without breaking up.

Did the same below 3000 (knowing it wouldn't take more than about 650) and it broke up at...er...as you guessed it..650.

Which one does this fall into?
a. Critical speed affected by alt in real life?
b. FB physics engine/FMs not [so] applicable above certain alts?

Cheers,
Norris


================================================== ==========

: Chris Morris - Blue Jam : http://cabinessence.cream.org/

More irreverence:
http://www.tvgohome.com/

NorrisMcWhirter
03-12-2004, 06:35 AM
Hi,

Took the MiG3(shvak) up to 9k to follow a 109, the other day.

In a dive, the MiG3 managed about 800kmh without breaking up.

Did the same below 3000 (knowing it wouldn't take more than about 650) and it broke up at...er...as you guessed it..650.

Which one does this fall into?
a. Critical speed affected by alt in real life?
b. FB physics engine/FMs not [so] applicable above certain alts?

Cheers,
Norris


================================================== ==========

: Chris Morris - Blue Jam : http://cabinessence.cream.org/

More irreverence:
http://www.tvgohome.com/

IAFS_Painter
03-12-2004, 07:05 AM
How were you measuring speed?

True air speed at altitude can be significantly greater than indicated air speed.

I stand to be corrected - but I'd expect the MiG to break up at the same IAS over most of it's height range ...

... BUT that true air speed will be higher at higher altitudes.

http://www.robert-stuart.me.uk/il2/signature/paint_sig_003.jpg
il2airracing.com (http://www.il2airracing.com) Painter's Pages (http://www.robert-stuart.me.uk/il2)
I've given up correcting my own spelling
Unless I've corrected it here

Maple_Tiger
03-12-2004, 08:23 AM
Think about it this way or picture a swimmer swimming along nisely.

What would happen to the swimmer's performance if the densidy of the water changed?

If the water became thinner then would not the swimmer lose some performnce?

Capt. 361stMapleTiger.

http://www.imagestation.com/picture/sraid78/pd6c878f0006c224805da6c9645408b41/fb291d3e.jpg

Proud member of the FBAA and Nutty Philosohpy Club.