Archived posting to the Leica Users Group, 2002/03/06
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]LOL You're welcome Ernie. Figured what I can't answer Leica-wise, I might be able to make up for in a subject I should know something about:-) Best, Duncan I love it! I ask a definite OT ? and I get more than enough; a poor soul asks about R6.2 and gets bupkus - anyone know if it's a full moon out cause it sure feels like it. Once again Duncan thanks for the answer. ernie - -----Original Message----- From: owner-leica-users@mejac.palo-alto.ca.us [mailto:owner-leica-users@mejac.palo-alto.ca.us]On Behalf Of DUNCAN Sent: Wednesday, March 06, 2002 2:40 PM To: leica-users@mejac.palo-alto.ca.us Subject: [Leica] Flying Upside Down - Optical Question OT The trick is to get the air flowing faster over the wing's upper surface than the lower surface. Normally, a wing does this two ways. First, the upper surface of the wing is longer than the lower surface (we call this a "cambered" airfoil). Second, the wing is tilted leading edge up and trailing edge down (we call this "angle of attack") which helps to force the air going over the upper surface to travel farther and therefore faster. To fly upside down with lift still pointing upwards, you need to tilt the upside-down wing even farther (leading edge up even more) to get the air to still flow faster over the top. This means you now have to fight against effect of the camber. Planes designed to fly upside down, like stunt planes, sometimes have wings without camber. That is, their airfoil shape has the same upper and lower surface shape, so the wing can fly equally well right side up or upside down. So, not all planes can fly upside down, but.... Hope this helps, - -Duncan We make a living by what we get, we make a life by what we give. http://www.leica-gallery.net/ http://groups.yahoo.com/group/MUGers B.D. - great question. I think I know the answer but I'll wait with you to hear from people who are definitely going to know. After that the smart people can answer me why is that airplanes can fly upside down - if flying upright caused a vacuum just above the wing creating lift then flying upside down should cause the wing to move down. This has bothered me for near on 2 decades. I get bothered easily ernie - -----Original Message----- From: owner-leica-users@mejac.palo-alto.ca.us [mailto:owner-leica-users@mejac.palo-alto.ca.us]On Behalf Of B. D. Colen Sent: Wednesday, March 06, 2002 1:18 PM To: leica-users@mejac.palo-alto.ca.us Subject: [Leica] Optical Question Okay, all you Optigods, a question for you: If a + diopter is a magnifier, wouldn't a +1.25 diopter do the same thing that the new $229 Leica M 1.25 Viefinder magnifier does - for $73, without protruding from the back of the camera, and without the really cute little chain and carrying case? - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html