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#11
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On Sun, 20 Jul 2003 14:43:58 GMT, Dave Hyde wrote:
Roger Halstead wrote: I guess you'd need some sort of plastic overlay for the airspeed indicator to remind you of the new critial speeds. They don't change all that much. You leave them set for the shorter wing. ... I think someone else said this too, and I find it confusing. If they don't change that much, why have the extensions? Just for more fuel? They can be used for additional fuel and they create a higher aspect ratio for greater speed at altitude than the short wing.. They also offer a bit more climb, and a bit slower landing. OTOH although the landing is slower, fowler flaps and the extended wing only lower the landing speed a few MPH The airpseed indicator could certainly be marked that way and inspectors may approve it, but it seems like the long-wing version would be more critical for safety numbers. Vne would likely be lower It's not. That depends more on other factors for the long wing(*), and maneuvering speed will be lower as well, It is by a little assuming the extensions add any lift at all. They do. Stall speed for *both* wings is important. Stall with the longer wing is only a couple MPH slower. (*) Assuming it's flutter that sets Vne, which is a big assumption. Kinda, sorta...flutter is one. Various portions of the structure are another. As Roger Halstead (K8RI EN73 & ARRL Life Member) www.rogerhalstead.com N833R World's oldest Debonair? (S# CD-2) Dave 'corner speed' Hyde |
#12
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#13
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#15
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Funny you should bring this up. I've been considering a series of very
narrow (high aspect) winglets which would pivot at their roots and be attached to the end of the wing. These could be arranged to work together as a very high lift arrangement and be foldable on-the-fly. A lot like the wingtip feathers of large raptors. Aft winglets might be shorter than fwd ones, and each "feather" might be only 2-3" in chord. Jay wrote: Seems like it might be useful to have removable wing extensions for an experimental. There are times when you want a fast airplane for cross country and you can stand a long runway for the high TO/landing speeds and then there are other times you want the low speed handling for short field, etc. Flaps do this to some degree depending on how exotic you want to get and have the advantage of being adjustable in flight but the wing extensions would appear to extend the flight envelope (on separate flights) beyond what can be done with typical flap configurations. A solid composite structure, perhaps 2 feet on each side that plugs into the main spar(s) would do nicely to allow you to have both a high speed clipped wing plane (when removed) and a long wing high lift plane, of course not at the same time. The further out you go on the wing the less the loads are so these wouldn't have to be built up as strong as other parts. They could be made with no control surfaces or other moving parts. You could even select a different airfoil for that section if you wanted. No problem plugging composite extensions into an aluminum main wing. Of course the main short wing would have to be built to allow access to the main spar(s). A hollow rectangular cross section spar could accept an insert to mate with removable extensions. I guess you'd need some sort of plastic overlay for the airspeed indicator to remind you of the new critial speeds. Anyone seen anything like this? |
#16
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Dave Hyde wrote: Roger Halstead wrote: The airpseed indicator could certainly be marked that way and inspectors may approve it, but it seems like the long-wing version would be more critical for safety numbers. Vne would likely be lower for the long wing(*), and maneuvering speed will be lower as well, assuming the extensions add any lift at all. Stall speed for *both* wings is important. Forget "stall speeds." A given airfoil stalls at a given AOA. Period. Loading, airspeed, aspect ratio have nothing to do with it. Get an AOA indicator and fly that. |
#17
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On 24 Jul 2003 08:20 PM, Grieg Pedersen, Information Systems Engineer
posted the following: Jim Phoenix wrote: (Bob Kuykendall) wrote in message Are there any powered aircraft out there with negative flap positions for faster cruising/lower drag? Several. the Seawind comes to mind as one that uses a "reflex" position for cruise. Initial reports indicate that the Barrows Bearhawk can get a lot of benefit from reflexing the flaps slightly at cruise. ---------------------------------------------------- Del Rawlins- Remove _kills_spammers_ to reply via email. Unofficial Bearhawk FAQ website: http://www.rawlinsbrothers.org/bhfaq/ |
#18
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Bob, Bob, Bob,
You can make a AOA indicator for $50 and a little bit of time to machine a dual purpose pitot - AOA pylon for the end of your wing. I do agree that many gauges on the dashes of many kitbuilts are worth a great deal less than the asking price, but a stall warning system is worth its weight in gold!!! Just ask the gentleman that "made it" to Oshkosh in a Glasair got stuck behind a cub on final, did "s" turns until he fell out of the sky 400 ft short of the runway. DEAD. Another Information System Engineer, but without a gold lined wallet. -- Bart D. Hull Tempe, Arizona Check http://www.inficad.com/~bdhull/engine.html for my Subaru Engine Conversion Check http://www.inficad.com/~bdhull/fuselage.html for Tango II I'm building. Barnyard BOb -- wrote: "Grieg Pedersen, Information Systems Engineer" wrote: The airpseed indicator could certainly be marked that way and inspectors may approve it, but it seems like the long-wing version would be more critical for safety numbers. Vne would likely be lower for the long wing(*), and maneuvering speed will be lower as well, assuming the extensions add any lift at all. Stall speed for *both* wings is important. Forget "stall speeds." A given airfoil stalls at a given AOA. Period. Loading, airspeed, aspect ratio have nothing to do with it. Get an AOA indicator and fly that. +++++++++++++++++++++++++++ A rather amusing, although assinine approach.... Killing a bug with an extravagant $ledge hammer. Is this what pompous information system injun-eers are good at? Barnyard BOb -- limited resources |
#19
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Bob, Bob, Bob, You can make a AOA indicator for $50 and a little bit of time to machine a dual purpose pitot - AOA pylon for the end of your wing. I do agree that many gauges on the dashes of many kitbuilts are worth a great deal less than the asking price, but a stall warning system is worth its weight in gold!!! Just ask the gentleman that "made it" to Oshkosh in a Glasair got stuck behind a cub on final, did "s" turns until he fell out of the sky 400 ft short of the runway. DEAD. Another Information System Engineer, but without a gold lined wallet. -- Bart D. Hull +++++++++++++++++++++++++++++++++++++++++++ Jezus... Just admit you know not how to fly small GA aircraft. You sound like one of the typical dumb**** cable infomercials. Gimmee a break and quit insulting my meager intelligence. Glasairs and Cubs will never mix and starring at a homebrew AOA on a wingtip instead of where one is going while attempting to navigate the world's busiest airport at rush hour is... extremely poor form in my 50 year old book of competent piloting. You can X, Y, Z or S 'til hell freezes over, but .... Not even a $5000 AOA indicator can substitute for good judgment and save your dumb ass when you should be on final at 100 mph instead of attempting to match wits with a 40 mph Cub.... if what you say has even a grain of truth in it. I've successfully flown thousands of hours on the ragged edge of stall crop dusting and I attribute that more to being competent at stall recognition than some $50 huckster claim of a life saving device for dummies. FWIW.. I've been hearing and reading about cheapy AOA indicators for the better part of 50 years. If they were worth a hoot, you or somebody would be selling them for $100 and getting rich.... or getting your ass sued into oblivion. P.S. Have you installed the $50 AOA on your, yet to fly, Tango? BE HONEST or you will crash and burn behind a Piper Cub. P.S.S. What is it with you Information System Engineers that make you brag about your credentials in a pilot oriented community? From what I have seen in the last 24 hours.... It's hardly an asset when garbage in = garbage out. Barnyard BOb - please don't 'ax' me to talk to dead men |
#20
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Since there seems to be a thought that we all need an AOA indicator, I have
missed something. Are there planes that give no indication of an impending stall? Isn't a large part of flight training concentrated on recognizing that impending stall? The people with whom I have flown who regularly fly the ragged edge of the bottom end of the airspeed ignore the stall warning horn and just fly the plane. That isn't flying by the seat of one's pants, its understanding the what the normally present indicators are telling you. I will have to agree that no one survives all those years crop dusting by looking at some kind of gauge. It is flying skill and knowledge. On a much smaller scale it's like getting to the point as a student when you realize you are flying approach and discovering you're not having to watch the airspeed indicator gauge...and you're squeaking it on. Bruce A. Frank "Barnyard BOb --" wrote in message ... Bob, Bob, Bob, You can make a AOA indicator for $50 and a little bit of time to machine a dual purpose pitot - AOA pylon for the end of your wing. I do agree that many gauges on the dashes of many kitbuilts are worth a great deal less than the asking price, but a stall warning system is worth its weight in gold!!! Just ask the gentleman that "made it" to Oshkosh in a Glasair got stuck behind a cub on final, did "s" turns until he fell out of the sky 400 ft short of the runway. DEAD. Another Information System Engineer, but without a gold lined wallet. -- Bart D. Hull +++++++++++++++++++++++++++++++++++++++++++ Jezus... Just admit you know not how to fly small GA aircraft. You sound like one of the typical dumb**** cable infomercials. Gimmee a break and quit insulting my meager intelligence. Glasairs and Cubs will never mix and starring at a homebrew AOA on a wingtip instead of where one is going while attempting to navigate the world's busiest airport at rush hour is... extremely poor form in my 50 year old book of competent piloting. You can X, Y, Z or S 'til hell freezes over, but .... Not even a $5000 AOA indicator can substitute for good judgment and save your dumb ass when you should be on final at 100 mph instead of attempting to match wits with a 40 mph Cub.... if what you say has even a grain of truth in it. I've successfully flown thousands of hours on the ragged edge of stall crop dusting and I attribute that more to being competent at stall recognition than some $50 huckster claim of a life saving device for dummies. FWIW.. I've been hearing and reading about cheapy AOA indicators for the better part of 50 years. If they were worth a hoot, you or somebody would be selling them for $100 and getting rich.... or getting your ass sued into oblivion. P.S. Have you installed the $50 AOA on your, yet to fly, Tango? BE HONEST or you will crash and burn behind a Piper Cub. P.S.S. What is it with you Information System Engineers that make you brag about your credentials in a pilot oriented community? From what I have seen in the last 24 hours.... It's hardly an asset when garbage in = garbage out. Barnyard BOb - please don't 'ax' me to talk to dead men |
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