long wire antenna
in [Repair]
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From: AZ Nomad on 9 Mar 2010 09:50 On Tue, 9 Mar 2010 06:07:42 -0500, Leonard Caillouet <nospam(a)noway.com> wrote: >"AZ Nomad" <aznomad.3(a)PremoveOBthisOX.COM> wrote in message >news:slrnhpbef2.o0t.aznomad.3(a)ip70-176-155-130.ph.ph.cox.net... >> On Mon, 08 Mar 2010 21:47:35 -0500, Rich Webb <bbew.ar(a)mapson.nozirev.ten> >> wrote: >>>On Mon, 08 Mar 2010 20:29:02 -0600, AZ Nomad >>><aznomad.3(a)PremoveOBthisOX.COM> wrote: >> >>>>On Mon, 08 Mar 2010 21:12:26 -0500, Rich Webb >>>><bbew.ar(a)mapson.nozirev.ten> wrote: >>>>>On Tue, 9 Mar 2010 01:53:39 -0000, "Arfa Daily" >>>>><arfa.daily(a)ntlworld.com> wrote: >>>> >>>>>>I saw an interesting dissertation on this some time back, which put >>>>>>forward >>>>>>a much more complex but better believable theory as to how a wing >>>>>>flies. >>>> >>>>>It's not really that complex. Didn't you ever, as a kid, hold your arm >>>>>out the car window with your hand flat and "fly" it up and down as you >>>>>changed the angle of attack? That's really all that's necessary. An >>>>>airplane could fly (if not very efficiently) with wings made from flat >>>>>sheets of plywood. >>>> >>>>All you've got there is an inclined plane. You aren't creating lift. >>>> >>>>Try it without the car. >> >>>The saying goes something like: with enough power, you could fly a >>>brick. The lift comes from the angle of attack. >> >> Nope. You're just describing a fin. >> >> Lift comes from turbulance on the upper edge causing a vacuum. >> Without the airfoil, what you have is pre wright brothers technology >> which didn't fly. >> >Lift is still lift, whether it comes from the shape of the device or the >angle of attack. When you change the angle you increase the pressure on the >bottom. With a difference in pressure you have lift. As has been said >before, not very efficient, and not straight up, and therefore difficult to >create controlled flight. Go build an airplane using just a fin sometime. Video tape and it can be added to all the other hilarious video footage pre wright brothers flying machines.
From: Rich Webb on 9 Mar 2010 13:30 On Tue, 09 Mar 2010 08:50:36 -0600, AZ Nomad <aznomad.3(a)PremoveOBthisOX.COM> wrote: >On Tue, 9 Mar 2010 06:07:42 -0500, Leonard Caillouet <nospam(a)noway.com> wrote: >>"AZ Nomad" <aznomad.3(a)PremoveOBthisOX.COM> wrote in message >>news:slrnhpbef2.o0t.aznomad.3(a)ip70-176-155-130.ph.ph.cox.net... >>> On Mon, 08 Mar 2010 21:47:35 -0500, Rich Webb <bbew.ar(a)mapson.nozirev.ten> >>> wrote: >>>>On Mon, 08 Mar 2010 20:29:02 -0600, AZ Nomad >>>><aznomad.3(a)PremoveOBthisOX.COM> wrote: >>> >>>>>On Mon, 08 Mar 2010 21:12:26 -0500, Rich Webb >>>>><bbew.ar(a)mapson.nozirev.ten> wrote: >>>>>>On Tue, 9 Mar 2010 01:53:39 -0000, "Arfa Daily" >>>>>><arfa.daily(a)ntlworld.com> wrote: >>>>> >>>>>>>I saw an interesting dissertation on this some time back, which put >>>>>>>forward >>>>>>>a much more complex but better believable theory as to how a wing >>>>>>>flies. >>>>> >>>>>>It's not really that complex. Didn't you ever, as a kid, hold your arm >>>>>>out the car window with your hand flat and "fly" it up and down as you >>>>>>changed the angle of attack? That's really all that's necessary. An >>>>>>airplane could fly (if not very efficiently) with wings made from flat >>>>>>sheets of plywood. >>>>> >>>>>All you've got there is an inclined plane. You aren't creating lift. >>>>> >>>>>Try it without the car. >>> >>>>The saying goes something like: with enough power, you could fly a >>>>brick. The lift comes from the angle of attack. >>> >>> Nope. You're just describing a fin. >>> >>> Lift comes from turbulance on the upper edge causing a vacuum. >>> Without the airfoil, what you have is pre wright brothers technology >>> which didn't fly. >>> > > >>Lift is still lift, whether it comes from the shape of the device or the >>angle of attack. When you change the angle you increase the pressure on the >>bottom. With a difference in pressure you have lift. As has been said >>before, not very efficient, and not straight up, and therefore difficult to >>create controlled flight. > >Go build an airplane using just a fin sometime. Video tape and it can >be added to all the other hilarious video footage pre wright brothers >flying machines. Grab your video cameras, folks! http://www.hobbyplace.com/aircraft/toyplanes.php -- Rich Webb Norfolk, VA
From: Leonard Caillouet on 9 Mar 2010 13:33 "AZ Nomad" <aznomad.3(a)PremoveOBthisOX.COM> wrote in message news:slrnhpco1s.8kk.aznomad.3(a)ip70-176-155-130.ph.ph.cox.net... > On Tue, 9 Mar 2010 06:07:42 -0500, Leonard Caillouet <nospam(a)noway.com> > wrote: >>"AZ Nomad" <aznomad.3(a)PremoveOBthisOX.COM> wrote in message >>news:slrnhpbef2.o0t.aznomad.3(a)ip70-176-155-130.ph.ph.cox.net... >>> On Mon, 08 Mar 2010 21:47:35 -0500, Rich Webb >>> <bbew.ar(a)mapson.nozirev.ten> >>> wrote: >>>>On Mon, 08 Mar 2010 20:29:02 -0600, AZ Nomad >>>><aznomad.3(a)PremoveOBthisOX.COM> wrote: >>> >>>>>On Mon, 08 Mar 2010 21:12:26 -0500, Rich Webb >>>>><bbew.ar(a)mapson.nozirev.ten> wrote: >>>>>>On Tue, 9 Mar 2010 01:53:39 -0000, "Arfa Daily" >>>>>><arfa.daily(a)ntlworld.com> wrote: >>>>> >>>>>>>I saw an interesting dissertation on this some time back, which put >>>>>>>forward >>>>>>>a much more complex but better believable theory as to how a wing >>>>>>>flies. >>>>> >>>>>>It's not really that complex. Didn't you ever, as a kid, hold your arm >>>>>>out the car window with your hand flat and "fly" it up and down as you >>>>>>changed the angle of attack? That's really all that's necessary. An >>>>>>airplane could fly (if not very efficiently) with wings made from flat >>>>>>sheets of plywood. >>>>> >>>>>All you've got there is an inclined plane. You aren't creating lift. >>>>> >>>>>Try it without the car. >>> >>>>The saying goes something like: with enough power, you could fly a >>>>brick. The lift comes from the angle of attack. >>> >>> Nope. You're just describing a fin. >>> >>> Lift comes from turbulance on the upper edge causing a vacuum. >>> Without the airfoil, what you have is pre wright brothers technology >>> which didn't fly. >>> > > >>Lift is still lift, whether it comes from the shape of the device or the >>angle of attack. When you change the angle you increase the pressure on >>the >>bottom. With a difference in pressure you have lift. As has been said >>before, not very efficient, and not straight up, and therefore difficult >>to >>create controlled flight. > > Go build an airplane using just a fin sometime. Video tape and it can > be added to all the other hilarious video footage pre wright brothers > flying machines. I never suggested doing so. I simply pointed out that lift is a differential in air pressure. It is often assumed to apply only to wing shaped objects, but this is just an assumption. I don't think anyone here seriously thinks that a straight fin in a good idea for an airplane wing. Don't try to make an argument were there is none. Leonard
From: AZ Nomad on 9 Mar 2010 14:12 On Tue, 9 Mar 2010 13:33:43 -0500, Leonard Caillouet <nospam(a)noway.com> wrote: >"AZ Nomad" <aznomad.3(a)PremoveOBthisOX.COM> wrote in message >news:slrnhpco1s.8kk.aznomad.3(a)ip70-176-155-130.ph.ph.cox.net... >> On Tue, 9 Mar 2010 06:07:42 -0500, Leonard Caillouet <nospam(a)noway.com> >> wrote: >>>"AZ Nomad" <aznomad.3(a)PremoveOBthisOX.COM> wrote in message >>>news:slrnhpbef2.o0t.aznomad.3(a)ip70-176-155-130.ph.ph.cox.net... >>>> On Mon, 08 Mar 2010 21:47:35 -0500, Rich Webb >>>> <bbew.ar(a)mapson.nozirev.ten> >>>> wrote: >>>>>On Mon, 08 Mar 2010 20:29:02 -0600, AZ Nomad >>>>><aznomad.3(a)PremoveOBthisOX.COM> wrote: >>>> >>>>>>On Mon, 08 Mar 2010 21:12:26 -0500, Rich Webb >>>>>><bbew.ar(a)mapson.nozirev.ten> wrote: >>>>>>>On Tue, 9 Mar 2010 01:53:39 -0000, "Arfa Daily" >>>>>>><arfa.daily(a)ntlworld.com> wrote: >>>>>> >>>>>>>>I saw an interesting dissertation on this some time back, which put >>>>>>>>forward >>>>>>>>a much more complex but better believable theory as to how a wing >>>>>>>>flies. >>>>>> >>>>>>>It's not really that complex. Didn't you ever, as a kid, hold your arm >>>>>>>out the car window with your hand flat and "fly" it up and down as you >>>>>>>changed the angle of attack? That's really all that's necessary. An >>>>>>>airplane could fly (if not very efficiently) with wings made from flat >>>>>>>sheets of plywood. >>>>>> >>>>>>All you've got there is an inclined plane. You aren't creating lift. >>>>>> >>>>>>Try it without the car. >>>> >>>>>The saying goes something like: with enough power, you could fly a >>>>>brick. The lift comes from the angle of attack. >>>> >>>> Nope. You're just describing a fin. >>>> >>>> Lift comes from turbulance on the upper edge causing a vacuum. >>>> Without the airfoil, what you have is pre wright brothers technology >>>> which didn't fly. >>>> >> >> >>>Lift is still lift, whether it comes from the shape of the device or the >>>angle of attack. When you change the angle you increase the pressure on >>>the >>>bottom. With a difference in pressure you have lift. As has been said >>>before, not very efficient, and not straight up, and therefore difficult >>>to >>>create controlled flight. >> >> Go build an airplane using just a fin sometime. Video tape and it can >> be added to all the other hilarious video footage pre wright brothers >> flying machines. >I never suggested doing so. I simply pointed out that lift is a >differential in air pressure. It is often assumed to apply only to wing >shaped objects, but this is just an assumption. I don't think anyone here >seriously thinks that a straight fin in a good idea for an airplane wing. >Don't try to make an argument were there is none. I wasn't the idiot who suggested that waving your hand around from a car window was an example of lift.
From: Phil Hobbs on 9 Mar 2010 19:59
On 3/8/2010 8:53 PM, Arfa Daily wrote: > "Phil Allison"<phil_a(a)tpg.com.au> wrote in message > news:7vj3h1F7nuU1(a)mid.individual.net... >> >> "Arfa Daily" >> >>>> It's not unlike a wing. Almost any surface flat on the bottom and curved >>>> on the top can produce lift. >>>> >>> >>> So how come a symmetrical wing, such as might be found on a stunt plane, >>> still flies, and most asymmetric wings fly quite happily upside down ? >>> :-) >>> >> >> >> ** I ask people who *think* they know how a plane flys that same Q. >> >> Stumps them all the time. >> >> Goes to show how simple explanations are often highly flawed. >> >> >> >> ..... Phil >> >> > > I saw an interesting dissertation on this some time back, which put forward > a much more complex but better believable theory as to how a wing flies. I > don't really remember the details, but it relied heavily on the wing's angle > of attack into the air, to produce the pressure differential, and hence > lift. I seem to recall that it was the opposite way round from the > 'conventional' teaching of increased speed of the air over the top of the > wing reducing the pressure, and that this theory had the attack angle > causing compression under the wing, thereby increasing the pressure to > produce lift. I do, however, remember it saying that air has no > 'intelligence', and just because two previously adjacent molecules became > divided above and below the wing, there was nothing to say that they had to > form back up in the same way as they left the back edge of the wing, which > would require the air to move faster over the longer upper surface. I > believe it did say that the air actually does travel faster over the curved > face of the wing, and that the fact that it does, does produce a reduction > in pressure. However, this reduction is small, and only contributes a very > limited amount of lift, compared to the main mechanism that's at work. > > Arfa > > The Bernoulli principle (the one about the faster air flow corresponding to lower pressure) is sort of like the second law of thermodynamics (the one about heat never spontaneously flowing from cold to hot). It's a shortcut way to get the right answer, but doesn't have the satisfying feel of a real physical derivation. BTW by symmetry, symmetric wings require an angle of attack to generate lift. Otherwise how do they know which way to push? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net |