Question Pre-dive Setting my Compass

[DiveLvr]

I have a hypothetical question. Diving on a wreck I’ve never been on I ask the DM what compass heading the ship is laying at. The DM says the wreck is laying with the bow pointing at 197 degrees. I plan to go down the anchor line secures to the wreck and work my way down one side of the wreck and then back the same way I came. How should I adjust my compass before I jump into the water?

Doug

 

[happy-diver]

Reciprocal, the way back to not being reliant on scuba gear, heading

 

[Still Kicking]

I have a hypothetical question. Diving on a wreck I’ve never been on I ask the DM what compass heading the ship is laying at. The DM says the wreck is laying with the bow pointing at 197 degrees. I plan to go down the anchor line secures to the wreck and work my way down one side of the wreck and then back the same way I came. How should I adjust my compass before I jump into the water?

Doug

Depends where you tie into wreck. Set your compass on the bottom when you start your outbound swim so you know your reciprocal for the way back. But wrecks, being linear, should make the reciprocal course somewhat obvious.

Be aware close proximity to wreck may affect your compass.

 

[34109411]

I have a hypothetical question. Diving on a wreck I’ve never been on I ask the DM what compass heading the ship is laying at. The DM says the wreck is laying with the bow pointing at 197 degrees. I plan to go down the anchor line secures to the wreck and work my way down one side of the wreck and then back the same way I came. How should I adjust my compass before I jump into the water?

Doug

17 to come back home !!!!

 

[DiveLvr]

Depends where you tie into wreck. Set your compass on the bottom when you start your outbound swim so you know your reciprocal for the way back. But wrecks, being linear, should make the reciprocal course somewhat obvious.

Be aware close proximity to wreck may affect your compass.

I was on the Vandenburg, A huge wreck, that had terrible viz that day. Viz was so bad you could barely see radar! Anyway so assume I’m at the stern, as best as possible align the lubber line and body in the direction/heading of the wreck and with the bezel bracket in the N or 0, correct? That’s my heading and the return or reciprocal course is (-) 180.

Oh, thanks for the response.

 

[Divin'Papaw]

I rarely use a compass on a wreck. I use the wreck itself as a guide and use natural navigation. One potential issue with steel wrecks is they can throw off your compass, so keep that in mind if you plan to use a compass on a steel wreck.

377 to come back home

377? There are only 360 degrees on a compass. I assume you mean a 17 degree heading (377-360) coming back, which is what I would calculate.

 

[34109411]

I rarely use a compass on a wreck. I use the wreck itself as a guide and use natural navigation. One potential issue with steel wrecks is they can throw off your compass, so keep that in mind if you plan to use a compass on a steel wreck.



377? There are only 360 degrees on a compass. I assume you mean a 17 degree heading (377-360) coming back, which is what I would calculate.

lol my coffee was not strong enough this should be 17.

 

[The Chairman]

I rarely use a compass on a wreck.

Bingo, Yahtzee, Winner Winner Chicken Dinner! I can't ever remember using a compass on a wreck.

I always mark my downline in some way. Think of using a bit of orange perimeter tape, a spool with a cookie, whatever you find handy.

 

[Still Kicking]

One fun bit of natural navigation on wrecks .... if you drop in the sand, can't see the wreck and you're not sure which way to head, look for a fish. Swim toward the fish. When they run for cover, they will ALWAYS lead you to the wreck.

 

[The Chairman]

Swim toward the fish.

I was diving a wreck out of Pensacola, and it was hard to see the wreck for all the fish. In fact, one couple complained that they couldn't even find the wreck. So yes, fish love structure and a wreck provides them with beaucoup cover.