Deuce 1 #26 December 3, 2002 That thing gives me a tingly feeling like I'm climbing a rope.If it could work as an all-metal, I would definitely work as a composite. Nice little Rotax....... Quote Share this post Link to post Share on other sites
quade 4 #27 December 3, 2002 QuoteNice little Rotax....... Well, according to the second site I quoted, the Wee Bee only had a 30 horse power engine. Interesting . . . The trickiest part of the Switchblade is probably the swing-wing.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
Deuce 1 #28 December 3, 2002 The swing wing is to accommodate getting launched powerless from a Skyvan or something. On a powered version the swing wouldn't be necessary, I don't think. Wow. A composite version would weigh at least half as much, and even a Rotax 912 has about 80 horsepower. Twice the power and half the weight? Should be pretty neato when it's developed. Quote Share this post Link to post Share on other sites
VivaHeadDown 0 #29 December 4, 2002 I haven't seen the movie yet, but the shots from the website and the shot from the trailer blip look like the same design. Maybe there's another shot from the movie that I have yet to see that resembles more of a Tomahawk shape. Either way, very cool. Makes me wish I had a few years of Aerospace Design under my belt so I could really jump into this kind of project. Quote Share this post Link to post Share on other sites
AggieDave 6 #30 December 4, 2002 heh-heh, "jump into this kind of project..." Ok, sorry, wrong forum for that, its late, my brain has been deepfried from school and I thought that was semi-humorous...--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
quade 4 #31 December 4, 2002 Quote . . . but the shots from the website and the shot from the trailer blip look like the same design. No. clearly not. I'll overlook the fuselage design and nose section changes, but look at the wingtips. In the movie version, the control surfaces just don't seem to exist. Further, the wings of the real life version seem to be in three sections, but the wings of the movie version seem to be one-piece swing-wings, almost exactly like a Tomahawk cruise missle.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
skybytch 273 #32 December 4, 2002 Oh wow. Those look like they'd be way too much fun. Wonder if they're landable??? Quote Share this post Link to post Share on other sites
kallend 2,106 #33 December 4, 2002 QuoteQuoteIf it had gear, do you think it would be landable? What is it's stall speed? Wait, I'm doing some research about this right now. I just remembered something I saw in a Museum once . . . something from the late 1950s or possibly early 1960s. Very similar in design, but without the variable geometry wings and with a piston prop. How about this one with a 7'2" wingspan www.nasm.edu/nasm/aero/aircraft/stitssa2.htm... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
kevin922 0 #34 December 4, 2002 QuoteQuoteQuoteIf it had gear, do you think it would be landable? What is it's stall speed? Wait, I'm doing some research about this right now. I just remembered something I saw in a Museum once . . . something from the late 1950s or possibly early 1960s. Very similar in design, but without the variable geometry wings and with a piston prop. How about this one with a 7'2" wingspan www.nasm.edu/nasm/aero/aircraft/stitssa2.htm Holy crap i'd love to see that fly I saw a budwiser minijet at an airshow once.. not as small as that but very tiny for a jet. Quote Share this post Link to post Share on other sites
quade 4 #35 December 4, 2002 I've seen that one before, but it's not the one I'm talking about. No, the one I'm talking about has the pilot actually laying on top of the fuselage. Well, lookie what I just found in my inbox from the San Diego Aerospace Museum! quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
AggieDave 6 #36 December 4, 2002 I've seen RC planes bigger then that! Wow, that is pretty cool, though. Turbulant winds have to be a bad experience on that thing, though.--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
billvon 3,070 #37 December 4, 2002 >Turbulant winds have to be a bad experience on that thing, though. Why? Generally, higher wingloadings on aircraft improve performance in turbulence. Quote Share this post Link to post Share on other sites
AggieDave 6 #38 December 4, 2002 High wingloadings do, but so does sheer bulk. More mass to move, the less winds will effect it.--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
quade 4 #39 December 4, 2002 QuoteHigh wingloadings do, but so does sheer bulk. In either case it's a matter of the ratio of mass v. surface area affected by the change in wind direction and velocity (or wingloading). Higer wingloadings also imply higher stall and landing speeds which mean the gust factors will tend to be a smaller percentage of those speeds and therefore have less effect.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
JackMcCornack 0 #40 March 26, 2005 Interesting discussion; sorry I'm two years late on discovering it. I'm kindsa new to the guilty pleasures of the Internet; did an ego-trip Google of my own name and this forum came up. Anyway, it was great to see such interest in the Switchblade, and if anybody interested, I'll be happy to give complete (as much as our contract with the Bond people allows) feedback to all the questions raised on this string. So...let me know. Jack "Stop me before I design again" McCornack"Danger is my middle name." --J. D. McCornack Quote Share this post Link to post Share on other sites
airtwardo 7 #41 March 26, 2005 Hello Jack...and WELCOME! When I saw your name as a new user yesterday... I wondered if it was THAT Jack McCornack! So tell us..what's up with the Switch Blade THESE days? ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
MWGemini 0 #42 March 27, 2005 The part that gets me (from their site) is this: Quotethe aircraft is dynamically stable in all three axes, and like a parachute, has no elevator, rudder, or aileron input. Instead, the pilot has brakes on each wingtip, which control direction and drag, much like the brakes on a ram-air parachute. Wow. I did some aeronautical engineering in high school, and our wind tunnels were pretty basic, but making something that large and shaped oddly such as it is aerodynamically stable, that's impressive. And very, very cool. On a military oriented note, however, if the pilot deploys and leaves the PHASST to its own devices (programming, AAD, etc), wouldn't that make it more detectable to the enemy? Seems like having a similar system to current military static line jumps might be better (having the rucksack on a line suspended from the jumper). It would definitely affect the flight characteristics of the canopy, but not the flare, since it would touch down before the pilot does, which would reduce the wingloading. I guess that would require a canopy with a pretty broad range of handling characteristics though, to handle a change in wingloading that great. So- what is the latest development news on this? Mike Quote Share this post Link to post Share on other sites
airtwardo 7 #43 March 27, 2005 On the static line thought... Have it line connected to the operator, so that when he begins to deploy...the line pulls out the magic pin holding the whole thing together so it falls apart into small pieces that would be harder to detect and impossible to reconstruct... It's the military! use 'em once and toss 'em! ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
MWGemini 0 #44 March 27, 2005 Well, that's another possibility, but if a team is trying to insert somewhere covertly, as the design implies, you don't want to be raining composite glider materials over a few square mile area. Makes people look up. The cost is not really an issue, since spec ops teams pretty much have a blank check with which to play (at least in my experience), but having the option to re-use them would be very cool. I'm not talking in training, I mean during actual combat use. I'm picturing a team with a high altitude exit, flying over their target, ditching the sled, and letting it fly itself back over international waters for recovery by a sub. That might negate the advantages of extended glide, however, since they would have to ditch the gliders that much higher to allow for return flight. From a technical standpoint, it is a very cool item. From a tactical standpoint, it seems like there are other issues that need to be resolved. Especially if they use a powered version, in which case increased noise would be an extra factor to consider. Mike Quote Share this post Link to post Share on other sites
airtwardo 7 #45 March 27, 2005 but if a team is trying to insert somewhere covertly, as the design implies, you don't want to be raining composite glider materials over a few square mile area. Makes people look up. Quote Hummm...good point. I know!! LAND 'EM!! ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
billvon 3,070 #46 March 27, 2005 >the aircraft is dynamically stable in all three axes . . . I'd believe pitch, since aircraft can be designed with longitudinal stability that comes from changes in airspeed due to pitching moments. Roll is a bit tougher, but things like dihedral and washout can help you return to zero roll after an upset. Yaw is _very_ tough. Most aircraft will not return to their original heading after an upset without an active system like an autopilot. But I would definitely believe that they can be made as stable as any other aircraft (which they are.) >Instead, the pilot has brakes on each wingtip, which control direction >and drag, much like the brakes on a ram-air parachute. Larger aircraft (especially fly by wire) do this as well. Watch the wing on an A320 when it's turning. You'll see the speedbrakes deploy on the low wing when the plane is in a steep bank. This is primarily to reduce adverse yaw, but also (in effect) turns the plane using drag. Quote Share this post Link to post Share on other sites
kallend 2,106 #47 March 27, 2005 Quote>the aircraft is dynamically stable in all three axes . . . I'd believe pitch, since aircraft can be designed with longitudinal stability that comes from changes in airspeed due to pitching moments. Roll is a bit tougher, but things like dihedral and washout can help you return to zero roll after an upset. Yaw is _very_ tough. Most aircraft will not return to their original heading after an upset without an active system like an autopilot. But I would definitely believe that they can be made as stable as any other aircraft (which they are.) >Instead, the pilot has brakes on each wingtip, which control direction >and drag, much like the brakes on a ram-air parachute. Larger aircraft (especially fly by wire) do this as well. Watch the wing on an A320 when it's turning. You'll see the speedbrakes deploy on the low wing when the plane is in a steep bank. This is primarily to reduce adverse yaw, but also (in effect) turns the plane using drag. For a mere $80 I bought a "heading hold" piezo gyro for my latest R/C helicopter.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
JackMcCornack 0 #48 March 28, 2005 Re yaw stability: your deduction is correct; as test flown and as delivered to EON they will return to a heading after they've been disturbed from it, but from a technical/operational standpoint it's trivial--a small rudder with an RC servo and a GPS driver. If we were going to provide these for covert insertions (instead of playing let's-pretend for the movie folks) we probably wouldn't bother switching the heading holder off. The tip draggers are lots more powerful than the rudder, if the pilot needs to maneuver, just do it; when done, let go of the brakes and it'll find its way back on track. Re stability in general: thanks for the complement regarding the difficulty. This was the first aircraft I ever designed (or built) where I wasn't qualified to do the test flying, and we had one big question that only test flying would answer: when the pilot left the Switchblade, and the wing loading dropped by 75%, would it pitch up and smite him? So we made the test mule rock steady and stable in stall as well as flight, to let Alan have the best shot at getting free of it. Frankly, making it fly was never a concern (for me it wasn't, though the film folks had every right to wonder). The concern was; how good a jump platform can we make a 70 pound airplane the size of a sportbike? Jack"Danger is my middle name." --J. D. McCornack Quote Share this post Link to post Share on other sites
quade 4 #49 March 28, 2005 Jack -- Can you tell us (ok me) how much was practical footage and how much was CGI or bluescreen? As I stated earlier in the thread, much of the movie footage looked pretty unrealistic as far as the launch and separation shots were concerned.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
Praetorian 1 #50 March 28, 2005 Mind giving some specs? Stall speed glide ratio etc.. I know all of these are dependent on the weight/drag of the pilot ... but ball park numbers? Good Judgment comes from experience...a lot of experience comes from bad judgment. Quote Share this post Link to post Share on other sites
