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XyZspineZyX
07-09-2003, 01:23 AM
I know the last spitfire marks were using contra rotating propellors. Sum pics.

http://www.vflintham.demon.co.uk/aircraft/spit/seaf9.jpg


http://www.vflintham.demon.co.uk/aircraft/spit/seaf8.jpg


Site said these were the seafire equlivants to the mk.24 and mk.22, mk.22 equlivant is the bottom pic, and i know the F.21 was tested with them just what are the advantages of contra rotating propellors.

http://www.vflintham.demon.co.uk/aircraft/spit/seafire.htm

planes r like mk45 46.

http://lamppost.mine.nu/ahclan/files/sigs/spitwhiners1.jpg


Message Edited on 07/09/03 01:24PM by HellToupee

Message Edited on 07/09/0301:26PM by HellToupee

XyZspineZyX
07-09-2003, 01:23 AM
I know the last spitfire marks were using contra rotating propellors. Sum pics.

http://www.vflintham.demon.co.uk/aircraft/spit/seaf9.jpg


http://www.vflintham.demon.co.uk/aircraft/spit/seaf8.jpg


Site said these were the seafire equlivants to the mk.24 and mk.22, mk.22 equlivant is the bottom pic, and i know the F.21 was tested with them just what are the advantages of contra rotating propellors.

http://www.vflintham.demon.co.uk/aircraft/spit/seafire.htm

planes r like mk45 46.

http://lamppost.mine.nu/ahclan/files/sigs/spitwhiners1.jpg


Message Edited on 07/09/03 01:24PM by HellToupee

Message Edited on 07/09/0301:26PM by HellToupee

XyZspineZyX
07-09-2003, 01:38 AM
Assuming we're talking about two propellors mounted on a single engine and rotating in opposite directions (rather than simply a counter-clockwise rotating propellor /i/smilies/16x16_smiley-wink.gif ), the main advantage would be elimination of yaw induced by helical propwash. P-factor and torque induced roll would also be reduced or eliminated.

XyZspineZyX
07-09-2003, 01:42 AM
all that .. plu si assume more power from a smaller prop diameter

XyZspineZyX
07-09-2003, 03:38 AM
And those are tri-blad props, unlike standar spitfir 5 bladers.

So, smaller diameter for the extra blade, probably better acceleration, but i think its mainly to eliminate prop torue.

Remember, the soviets (US, too?) had an attack chopper with couter rotationg blades, no need for a tail rotor.

XyZspineZyX
07-09-2003, 05:06 AM
yes i belive one of the reasons was to help with tourqe, probly could open her up on take off with out worring about havint to counter with the rudder.

http://lamppost.mine.nu/ahclan/files/sigs/spitwhiners1.jpg