SayethWhaaaa 245 Posted May 21, 2007 Have a butcher's at this Hind on display... http://www.spikedhumor.com/articles/106395...his_Flying.html Cool... huh? Share this post Link to post Share on other sites
+Rogue Vulcan 0 Posted May 21, 2007 I'm guessing this explanation is the correct one? "They are using jet turbines. This is a stunt used at air shows " All the other comments on that video seem to think that the RPM of the blades could be exactly the same as the FPM of the recording device, which just sounnd ridiculous. Still, that does look pretty cool! Share this post Link to post Share on other sites
BUFF 8 Posted May 21, 2007 I'm guessing this explanation is the correct one? "They are using jet turbines. This is a stunt used at air shows " of course they are - it's a turboshaft (2 Klimovs) powered chopper! without rotors turning though you would need vectored thrust a la Harrier & I don't see any nozzles in the video (plus it would have to be a 1 off special as I've seen a Hind in real life both in static & displaying & they don't have vectored thrust as standard). http://video.google.com/videoplay?docid=-7076349679064042453 typical chopper (don't know exact Mi-24 figure) main rotor RPM is 300-400 = ~5-6.67/s but there are 5 blades on a Hind which gives you 5 chances of a blade being in the same place per rotation for each frame so 25-33 chances/ second. typical camcorder fps ~29-30 so it's definitely in the right ball park nos. wise Share this post Link to post Share on other sites
FastCargo 412 Posted May 21, 2007 I don't understand why people keep getting perplexed by this one. I must have seen 3 separate threads on various boards about it. They matched the camera frame speed to the rotor speed. It isn't that hard. Hell, anyone remember the show Airwolf? You saw almost exactly the same thing when they went into 'turbo' mode. The camera frame speed was slowed down for recording then played back at normal speed to make the aircraft appear like it was going fast. It had the side effect of making the rotors appear to not rotate properly. Now, in Airwolf, each exposure was longer, so the blades looked like stationary wedges. In this Hind video, the same thing occurs, except the individual frames exposure is much shorter, so the rotors aren't blurred (you can see the tips are just ever so slightly blurry). FastCargo Share this post Link to post Share on other sites
+SkippyBing 8 Posted May 21, 2007 Exactly, the main rotor RPM is a multiple of the FPS of the video recorder. I've got some footage somewhere of our Lynx and it looks like the main rotor is going backwards very slowly, it's a bit un-nerving the first time you see it played back! Ultimately it's a pain in the ass if you're trying to make a video because everyone just goes 'Oh look the rotors have stopped', retards. Share this post Link to post Share on other sites
SayethWhaaaa 245 Posted May 22, 2007 cool vid, thanks :) Cool vid, huh? Yeah, it's a frame rate issues like BUFF said. I just thought it was cool. How often do you see a coinsidence like rotors and framerates syncing? Just so you know if you're confused, jet powered choppers are much louder and more jet sounding. And this one's got that sexy Hind sound... (no, that's not a fart joke ) Share this post Link to post Share on other sites
