We were told that the plane was at 745 knots, which at sea level is .9999 the speed of sound. Had that area of compression slid off the rear of the aircraft there would have been a sonic boom. :-) As a kid at air shows they were occasionally heard but the restrictions are very strict now. One of the Blue Angels made a VERY low pass at about the same speed, not 20 feet off the water. There was a wake and small rooster tail behind the jet that was visible for the entire 3 mile pass! Unfortunately I didn't have the camera ready and missed it except for seeing the last 100 yards, about a tenth of a second!
Walt On Sat, Nov 8, 2008 at 10:56 PM, Joseph McAllister <[EMAIL PROTECTED]> wrote: > > On Nov 8, 2008, at 19:42 , Rick Womer wrote: > >> Excellent, Walt. >> >> In #9, why is the back 1/3 of the plane blurred? Water vapor on a humid >> day? > > A plane's wings passing through the air by it's airfoil nature compresses > that air, then allows it to decompress after it passes. This sudden > decompression forces any moisture out of the air, causing those vapor > clouds. As a plane approaches the speed of sound, that cloud will work it's > way towards the nose of the plane when the shock wave the plane produces > becomes almost a solid that, once passed, again, is releasing the pressure > of the compressed air mass and forming a "cloud". > > Search the web for jets sound barrier for images of the phenomenon. > > Joseph McAllister > Pentaxian > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
