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Leg 57 results, question
From: Paul Hirose
Date: 1999 Aug 16, 14:21 EDT
From: Paul Hirose
Date: 1999 Aug 16, 14:21 EDT
I'm still working Silicon Sea Leg 57. Got some results: 1. DR at time of first sight (Mar 24 2342 Z) = 5330 S 7504 W. 2. Celestial fix 2342 Z = 5400 S 7445 W. 3. Speed made good between fixes = 11.4 kt. Computed current (not asked) = 2.0 kt at 160 deg. Please confirm latitude 5604 S for Cape Horn. I already had it plotted from the previous leg at 5640 S. Suspect one of these had transposed digits. All plotting was done on a piece of typing paper at 3 mi/mm. Sight reduction via 1998 Almanac and HO 211, pencil and paper. Moon shot not reduced because I don't have this year's Almanac. (By the way, the selection of stars was peculiar - 3 LOPs almost on top of each other, and Peacock making a decent cut angle with the others.) Current computed with E-6B air navigation computer. I'm a student pilot and needed the practice! That E-6B is a mechanical analog computer dating from the 1940s. The front face is dominated by a round slide rule for solving time-speed-distance problems. It's marked so you can work in seconds, minutes, or hours. Of course you can also use it for ordinary multiplication and division. There are special scales for pilot stuff, but they don't get in the way. For entertainment you can figure out Silicon Sea's Mach number, adjusted for air temp. On the back is a wind computer which works equally well for current if you mentally scale the speeds. For example, divide by 20 so 200 knots becomes 10.0. I bought my E-6B from Celestaire several years ago. It's well-built of aluminum and plastic. EMP-proof and Y2K-compliant. Look in any student pilot book at a library if you want details.