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Old 02-22-2007
btrayfors btrayfors is offline
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Capt Hand,

Yeah, easy, but I believe confusing on several counts.

First, the friends boat (Vessel #1) is on a COURSE of 036T, not a BEARING. His speed is 5 knots. His distance from your boat (Vessel #2) is 84nm. The BEARING to/from the vessels is ambiguous, the way it was presented. Normally, bearings are taken FROM your vessel, but the wording in the original is ambiguous, as in your solution. Either way, the answers provided do not agree with the computed values. Your boatspeed is 7 knots.

Let's assume that the bearing of 096T was, indeed, from Vessel 1 to Vessel 2. The reciprocal bearing, from your vessel to your friend's vessel, is then 276T.

If we then set up the problem in a conventional way, it looks like this:

Vessel #1 (friends boat): Bearing 276T Distant 84nm Course 036T Speed 5 knots

Vessel #2 (your boat): speed 7 knots

Required: course, time, and distance to intercept

According to the calculator (both of the aforementioned calculators agree):

Course to intercept: 314.21 T
Time to intercept: 10 hours 30 mins
Distance to intercept: 73.5 nm


Last edited by btrayfors; 02-22-2007 at 10:55 AM.
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