Marc Zeitlin Posted July 14, 2009 Share Posted July 14, 2009 yes ..... i do. I just expected better performance. I would imagine that is an airframe limitatio, yes? I would assume so. We know what happens when one assumes... I was just thinking in comparison to the Berkut 540 with a Vne of 250kts (if I remember correctly.)A LE jet can cruise at 25,000 ft., with a TAS of 315 kts and still be just at the Vne of 210 kts (Ignoring all the other issues that occur at those TAS's). You can't do that with the Berkut 540 - you might get up that high, but you won't be anywhere near your Vne of 250 kts. At 8k ft, where you'll get your best TAS at 75% power, you'll be at 290 kts. TAS, but I guarantee you that you won't get an IAS of 250 kts in level flight at that altitude, so that'll only happen in a dive. So the jet is clearly faster in level flight, but at a WAY higher fuel burn. Jets, however, make no sense whatsoever in non-pressurized aircraft - the only reason to do it is because you have more $$$ than you know what to do with and think it's really cool. Which it might be. Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
TMann Posted July 14, 2009 Share Posted July 14, 2009 Agreed on all counts but one. In terms of the airframe, a Vne of 210 will remain constant whether you are running a jet or a prop. I just was surprised that the airframe wasn't rated higher than that. (Disclaimer:) I'm not an engineer which is why I turn to you, Marc when I get into the guestion of modifications. That said, based on my limited knowledge on the subject, if you strapped that jet on a Berkut airframe, I would assume (yeah ... I know) that with the higher Vne, you could have greater capabilities. Granted, in a cross country race, the prop would be the likely winner with fewer pit stops. I don't know ........ I;m just thinking out loud. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
Marc Zeitlin Posted July 14, 2009 Share Posted July 14, 2009 ... based on my limited knowledge on the subject, if you strapped that jet on a Berkut airframe, I would assume (yeah ... I know) that with the higher Vne, you could have greater capabilities.Agreed. _IF_ it's based on airframe limitations. If based on flutter, then higher altitudes and higher TAS's will be an issue. The Vne's of these aircraft were set with the assumption that they'd be flown relatively low - 15K ft. or below, 99.99% of the time, and with normally aspirated engines, so no one paid attention to Mach effects or TAS effects when setting Vne. All bets are off when going high, due to these effects. So a provisional "agreed". Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
lancehooley Posted July 28, 2009 Share Posted July 28, 2009 This is the "classified" airframe mentioned in previous posts....the one in Florida. Different winglets. Quote Link to comment Share on other sites More sharing options...
Arbiter Posted July 28, 2009 Share Posted July 28, 2009 That's pretty sweet looking . I like the inlets! Don't forget the boudary layer diverters .... -Chris Quote Chris Zupp ~Aircraft Designer~ Preliminary Design Sequence I: Project Endeavour Aeronautical/Mechanical Engineer Private Pilot Link to comment Share on other sites More sharing options...
Lifessamsara Posted July 29, 2009 Share Posted July 29, 2009 No roll over protection? And if fitted, how would one get into the back seat with that canopy? Bruce. Quote Link to comment Share on other sites More sharing options...
TMann Posted July 29, 2009 Share Posted July 29, 2009 Bruce ....... what? Are you trying to be practical? I think that went out the window when they put a jet on it. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
Lifessamsara Posted July 29, 2009 Share Posted July 29, 2009 What ever was I thinking Tom? Ok then, it does take 'snarky' to the next level I must confess. I hope it has a very good canopy latching system, but at least if it departs in flight, it wont go through the prop! It may however interfere with the passengers back of head as it does a flip, but Im sure both pilot and passenger would be wearing 'bone domes' fighter style. Bruce Quote Link to comment Share on other sites More sharing options...
Spodman Posted July 29, 2009 Share Posted July 29, 2009 but Im sure both pilot and passenger would be wearing 'bone domes' fighter style....which will keep their heads looking nice for the relatives when they get scraped off... Does look nice though. Quote Mark Spedding - SpodmanDarraweit Guim - AustraliaCozy IV #1331 - Chapter 09www.mykitlog.com/Spodmanwww.sites.google.com/site/thespodplane/the-spodplane Link to comment Share on other sites More sharing options...
schmeddz Posted July 30, 2009 Share Posted July 30, 2009 This is the "classified" airframe mentioned in previous posts....the one in Florida. Different winglets. Lance, You make that jerky recipe I sentcha? V says you didn't yet. Get on it! LadyMare likes the gun I gave her. She didn't get the Glock 27 though. I'm too cheep. These guys are all gonna be sooooooo JEALous when you fly yer jet!!!! They already are, you can tell with all the naysayin'. I've already got my GEntex Bone bucket colors all picked out!!! I also got my O2 mask ready since I know we be crusin' at 25k plus... yeehaw! Quote Link to comment Share on other sites More sharing options...
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