Have I done my maths correctly?? 54 inch pitch X 4,000 rpm = 216000 inches travelled per minute 216000 inches X 60 min = 12960000 inches travelled per hour Divide by 63360 inches in a mile = 204.5 mph
10 % prop slip should be a possible 184.05 mph 58 inch X 3400 X 60 ~ 63360 = 186.74 mph 10% prop slip should be a possible 168.06 mph Phil Matheson SAAA Ch. 20 http://www.saaa20.org/ VH-PKR Australia EMAIL: phillipmathe...@bigpond.com KR Web Page: www.philskr2.50megs.com ------------------------------------------- Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html ----- Original Message ----- From: "Mark Langford" <n5...@hiwaay.net> To: "KRnet" <kr...@mylist.net> Sent: Sunday, May 17, 2009 1:19 AM Subject: KR> 193 mph! NetHeads, I finally got to fly again yesterday. Is seems the weather goes crappy as soon as I return, and then turns sunny and mild when I depart. But I squeezed in two hours yesterday while dodging rain showers, except I deliberately spent about five minutes in a downpour getting the wing leading edges and canopy cleaned with zero effort. I found myself over Lake Guntersville, and running wide open. I was playing fighter pilot and spotted two boats blasting along side by side, and split them down the middle from the other direction. I then hauled up and left on the stick, came back around at 90 degrees to them, and by pure coincidence, my shadow hit the first boat and then the second, with perfect timing. I guess that's as close as I'll get to strafing anything, but it was a lot of fun. I then did two wide open runs down the lake at 180 degree directions, comparing GPS numbers to IAS numbers. The end result was a straight-and-level average of 193 mph true airspeed! Things are supposed to be pretty nice next week, so I should be able to get in a few more hours (and a little sun) for a change. Life is good... Mark Langford N56ML "at" hiwaay.net website at http://www.N56ML.com -------------------------------------------------------- _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html
