Recovering Lost Rudder

[cbelg]

I will be attempting to recover a rudder that fell out of the boat while anchoring (long story) in the Hudson River just south of the Tappan Zee Bridge on the west bank. I was able to mark the location so I have an approx idea of where it is. Have setup a dive plan, but was wondering if anyone here has done any recovery in the hudson before and what the bottom will be like along with currents. Its only in about 12-15ft of water, and have a feeling will be 1' vis down there. The idea will be to try and time it for about an hour of down time and hit the site at slack tide. Going to try the little Nokta PulseDive metal detector to help find it. Any thoughts or advice welcomed.

 

[Gone for diving]

I was able to mark the location so I have an approx idea of where it is

Never done the Hudson,

Aprox position... how aprox,
Someone verbally telling you, is usually a waste of time, because they don't tell you right,

They have to be there to show you physically, like in a canoe or something.

But it sounds like you lost it?
You have a GPS mark?

It can be a huge haystack, especially if you are in a current.

If its shallow I have used a dry bag with hand held GPS to line me up drifting to the mark,

In a current a weight with a float to give surface visual reference can be handy,
Also have dropped an anchor with a rope in high current to be be able to move around and do some basic searching.....

1ft vis you will need it in front of your face to find it...

 

[cbelg]

Never done the Hudson,

Aprox position... how aprox,
Someone verbally telling you, is usually a waste of time, because they don't tell you right,

They have to be there to show you physically, like in a canoe or something.

But it sounds like you lost it?
You have a GPS mark?

It can be a huge haystack, especially if you are in a current.

If its shallow I have used a dry bag with hand held GPS to line me up drifting to the mark,

In a current a weight with a float to give surface visual reference can be handy,
Also have dropped an anchor with a rope in high current to be be able to move around and do some basic searching.....

1ft vis you will need it in front of your face to find it...

I marked it with gps. Should be within 50ft or so of where it fell. I don't know what vis will be but not expecting much if any. I'm hoping the pulsedive will be my eyes. Little concerned about how to move perpendicular to current. Plan is to lay a line off an anchor and work up current sweeping detector. The rudder is a 10"×20" blade with a 18" x 1.25" thick shaft on it. So I'm thinking the little device will have better range than say trying to find a ring or coin.

 

[-JD-]

A slight bit of current could be your friend if the bottom is easily disturbed.

My gut would be to run this as a partial circular search ... Place an "anchor" up current from the expected position and run a reference line down current. Run a series of arcs across the search field, stepping up current each time so the disturbed silt blows away from your future search area.

Best "anchor" would be a buddy with a reel who could signal the ends of the arcs (detected by angle and conveyed by tugs) and reel in the line to the next arc radius. Also holding the line high at the pivot point to keep it off the bottom/obstructions is huge! Pick a buddy with strong arms/shoulders.

Don't forget to pay attention to your basic dive. It is very easy to get wrapped up in the task loading of conducting the search.

Let us know how it goes.

 

[cbelg]

Jd, the buddy with a reel to step in is a great idea. I have 2 boats we are using to keep an area perimeter so we were either going to use an anchor line or tie off to the boat. Definitely going to work upstream so the disturbance drifts away and behind me.

Either way it's going to be an experience and I'm pretty confident of where it is, dive time wise I don't anticipate total dive time of more than an hour. I'm bringing a 120 so should have plenty of air.

It's been a while since I did manual calcs and didn't rent a computer, mine is 20 years old and regs would need recertification before I would use them. So I rented a full setup for the day. I'm only in 15ft max so don't have to worry about deco or anything.

 

[Gone for diving]

Do not know what type of current you have but don't underestimate drift when it fell in....
What's the bottom like? Arm deep of muck?

It's been a while since I did manual calls and didn't rent a computer, mine is 20 years old and regs would need recertification before I would use them.

Not sure I understand what you are saying here, but make sure you are totally comfortable it black out conditions,,,
sounds like it's a braille dive, and you better be ok laying in the muck, you will not be staying neutral in 1 ft vis, put an extra 2-5lb on,
The bottom is your friend when you are try to do stuff,
Remember working like that you don't have to look good, you just have to get the job done,


If its been a while, maybe go for a test dive somewhere nicer,

It really is a mind over matter in zero vis, sometimes closing your eyes let's you concentrate better, and map it in your head,

Don't be surprised if you do 2 or 3 dives to find it, at least it's a good size item,

 

[cbelg]

Do not know what type of current you have but don't underestimate drift when it fell in....
What's the bottom like? Arm deep of muck?

Not sure I understand what you are saying here, but make sure you are totally comfortable it black out conditions,,,
sounds like it's a braille dive, and you better be ok laying in the muck, you will not be staying neutral in 1 ft vis, put an extra 2-5lb on,
The bottom is your friend when you are try to do stuff,
Remember working like that you don't have to look good, you just have to get the job done,


If its been a while, maybe go for a test dive somewhere nicer,

It really is a mind over matter in zero vis, sometimes closing your eyes let's you concentrate better, and map it in your head,

Don't be surprised if you do 2 or 3 dives to find it, at least it's a good size item,

Typo, meant manual calculations to figure out dive times. I don't see any issues with an hour of bottom time in 15ft, if I'm wrong please tell me.

I'm not sure exactly what to expect but am preparing for the worst. Will probably be zero vis on the bottom, 1ft of muck. I am going in with a 7mm farmers suit so will be pretty well protected, and bringing lots of weights. Planned to start with about 20lbs plus probably 2lbs on each ankle. My idea is to start off with doing a test dive and checking buoyancy and current. See how I can stick to bottom and move around, see what visibility is like. Once I'm squared away and feel comfortable (relative to environment) I was planning on doing 15 min intervals and coming up to checkin topside, make sure I'm working area in the correct pattern.

If all goes well and my mark is good from when it fell, I think I find it within an hour. The rudder is solid brass plate 20"×10"x .5" thick with a 18" stainless shaft sticking out of it. So it most likely went straight down. What I'm worried about is how far it can have worked into the mud, and with each passing tide cycle did it go deeper.

I wasn't going to spring for a 1500 metal detector, so I went with the little Pulsedive for 200 bucks. I figured it will come in handy in the future of boating as this may not be the last item lost from a boat and we have already had a few guys at the marina lose things (a BBQ fell off back of another guys boat just last week). I tested it on some larger metal objects on land and its pinging them at about 5 or 6" pretty consistently and quickly. So if I can stay on the bottom and make my pattern correctly I can sweep in about a 3 to 5ft width and cover good ground.

 

[Gone for diving]

Yep sounds good, just be prepared to adapt,

Carry a small lift bag or something to help lift,,,, it probably is heavier than you think,

Just don't kill your self it's not worth it,

The challenge of it is fun...
Last year my buddy and I salvaged a bravo3 stern drive, in crazy fast water, 50ft,
surface support was not feasible,
120lb lift bag was maxed out,
Boy was that hard work.

 

[Johnoly]

Going to try the little Nokta PulseDive metal detector to help find it. Any thoughts or advice welcomed.

Or spend the time with a gopro camera on a line and then leave the line on the bottom so you can follow it down.

 

[cbelg]

Or spend the time with a gopro camera on a line and then leave the line on the bottom so you can follow it down.

Thought about sending camera down, but have been told visibility will be near zero.

Will know more later today. Heading down to get setup around 11, and should be doing test dove by 12/1230. Slack tide/high is scheduled for 2pm today.