NavList:

Yesterday was very windy here in Southern California and has been all month it seems and I decided to try some CN observations of the Sun at the beach with the wind blowing about 30kts. using a sight tube and a graph of pre-calculated altitudes (Hp). Timing was done using splits on a stop watch which allowed for 10 observations in 10 minutes without rushing the shots. Determining the intercepts was done on the spot taking less than 5 minutes including the average intercept. All the results were within plus or minus 1 minute of arc (most acceptable considering the windy conditions). On my up coming sea trial on a small craft I am anticipating plus or minus 2 minutes of arc (not in 30 kts. of wind though).

I don't recommend anyone try using their sextant at the beach in wind over 20 kts. When wind gets above 20 kts. at the beach sand starts to lift getting into everything. It required blowing, brushing and rinsing to get the sextant free of sand when I got back to my boat dock. Sand will crunch horribly when it gets between the micrometer drum and arc. This in fact cut short my beach observation trial. If you do decide to practice in messy conditions I suggest using an already abused sextant. I happen to have a beat up sextant so no worries (Mid 80's Cassens & Plath). I was surprised that the index error held constant and checked out to the same number after a full wash down and cleaning.

Greg Rudzinski
----------------------------------------------------------------
NavList message boards and member settings: www.fer3.com/NavList
Members may optionally receive posts by email.
To cancel email delivery, send a message to NoMail[at]fer3.com
----------------------------------------------------------------