Sunday, 11 August 2013

The compass deviation card, 24th June 1981

The subject came up on our local marina yesterday, a skipper preparing his yacht to go offshore asked what they looked like and how to make one?  The guy had an idea he could make one up while still on his marina berth, I suggested he could not and needed to be out in the bay so as to swing the compass and in a 360 turn.

I have this old card, dated back 32 years ago, done by Captain Robert (bob) Deacon and a past friend of mine, Bob would take you and your boat out early morning from the RCYC in Cape Town, even while going down the Duncan Dock, Bob  was taking bearings and making notes.

Click on the image for a larger view.

A quick trip into the bay, turn around and head back to moorings and it was all done. Of course Bob never told you what his marks were but for sure some tall buildings and spires must have been some of them. By the time we were tied up Bob had filled in the standard deviation card and for the charge of R65 as the service fee would hand you your card, thanks Bob!

I have suggested the skipper needs to make his own card, then take his boat into the bay, Hout Bay is a bit tight, so rather Chapmans Bay further outside, then as we now have GPS and using his handheld GPS he can swing his compass and make notes the the compass card against the GPS heading.

How easy is that!