Probably like in a car. Your front wheels aren't perfectly parallel either. They "toe-in" a few degrees to help hold a straight line when driving.

From what I have read it’s pretty standard to toe in rudders on large vessels. Toed-in rudders reduce drag, give crisper steering and more speed.

My guess is that it is due to the hydrodynamics of the outer props being forward of the inner set, as well as the relative positions of the props and rudder

It's to help reduce the induced drag from the stern of the ship. Think of a teardrop and how it reduces the low pressure zone behind an object.

Yep😊

Kinda like toe in & toe out on an automobile...

Wow! Thank You !:-)

Well, there's another reason...in straight ahead sailing, the canted port rudder exerts a starboard-wise force; the canted starboard rudder exerts a port-wise force. These forces combine on the centerline to assist in staying on centerline track and resisting the effect of winds and waves across the track. Some hovercraft bow thrusters are canted for the same reason.

Race boats do that today, depending on how the props turn [in or out] the drives are canted in or out for the best straight line tracking at speed

So it's not to trigger the Luerssen effect that the German Schnellboot torpedo boats used to reduce the ship's wake and improve performance? Edit: Oh wait, to get that effect the rudders should be angled outward and there needs to be a third rudder at the centreline

I saw that and wondered if it was Navy, shipyard, or museum paint slobs.

That is...not a bad idea.

The one true king of Texas? Isn't that Bob Wills?

You would need a bunch of sailors in general. These ships are designed with a crew of a couple thousand in mind, and while a bunch of that is redundancy and weapons systems, it also just takes a lot of people to make it run.

@@rulebretgne5244 if memory serves, around 300 just for engineering. So yeah, it's a lot cheaper to use the externally powered maneuvering device - a tugboat.

Navy rudder orders are always Right/Left because the helmsman isn't likely to react correctly to Port/Starboard. He's spent his whole life with R/L and in emergency might get it wrong! Everyone in the Navy including officers.

@@dpeter6396 What makes the helmsman so less familiar with P/S compared with everyone else on the ship? Would not the rest of the crew have spent just as long living with L/R that this argument would apply to the entire crew?

Any sailor who ever stood a helm watch knows this: The OD gives helm orders like "right standard rudder" and "left standard rudder"; likewise the after steering equipment shows right and left to make it simple if/when the backup steering crew is responding to the commands from the bridge. Gotta make things "sailor proof."

first rudder's

or the flow of water behind the ship, is oriented in such a way that 2 degrees in is most hydrodynamic.

It's probably also to align the rudders to the ship's wake. You can see waves on smaller ships that are formed by the water refilling the displacement left behind by the ship

A hunch - in the automotive trade, many vehicles - depending on type - have a similar condition with thier steering wheels, called 'Toe In'. Rarely youll see 'Toe Out' where the wheels point away slightly from each other. Reason for this is for the vehicle to handle appropriately for its design, load and so on. Incorrect toe can and will cause premature wear problems to the tires themselves. I would wager this is same here. The designers likely found that, for the ship to hold a straight course, her rudders had to be angled into each other. Another, albeit less likely option, is this -- I seem to recall that Iowa class BBs had significant vibration issues. This *may*, again, educated cross-field guess here, been an effort to stymy the vibration problem. However, my bet is on the handling, since, again IIRC, the vibration was never wholly cured. Yes, incorrect toe 'can' cause unusual feeling in the cars steering. Like I said. My trade is automotive service repair tech, but the base ideas hold the same - very roughly - between ship and car.

@@MoparNewport I wonder... if the flow of the water coming off the props creates a low pressure area at the stern... having the rudders angled in slightly may help negate this... which would decrease drag on the hull... equaling greater speed... but I have no idea.. just a farmer guess LOL

@@MoparNewporti wish i had a chrysler newport... 😢

@@MoparNewport Yep, I thought the same exact thing you did.

I have experience with much smaller boats, but I think the trim angle to account for the wake of the boat. As a boat moves through the water, water has to flow around the boat and fill the void left by the hull. The rudders are probably trimed to match that current.

It's highly doubtful. The Rudders are not critical to the Museum's operation.

@@WALTERBROADDUS Neither are the propeller shafts, glands, bearings, and seals, but they do need repacking to prevent leaks. Drydock is all about maintaining the things that need it, whether they're being used or not.

@@Turboy65 I'm sure those evaluations have already been made. And there is a cost benefit to disassembling systems to which there is no current issue.

Our horn works, we use it all the time, we probably won't do it underway, we won't have power on board.

With 4 props of which 2 are turning the opposite of the other 2, there would be no torque as they would cancel each other out. Light aircraft with a single engine do experience torque from the engine but it causes roll instead of pitch changes. Same deal with a single rotor helicopter and why they have the tail rotor, to counteract that torque.

Answered in other posts, but... The water flowing around & under the hull is rejoining together & the rudders are set to be straight with that local flow-direction.

Deserves more likes.

Were you on the Cochrane? I was on the Robison DDG 12.

Yes, I was on Cochrane at Pearl from 80 to 83 then we homeport shifted to Yokosuka in OCT 83 I left in April of 84. FTG1 (SW)@@gavinwright184

It is not uncommon in rear-wheel drive vehicles with independent rear suspension to have toe-in toward the center of the vehicle to assure neutral handling at the cost of tire life.

I think it is more to do with local current pattern. If you look at the wake pattern behind the ship, I wouldn't be surprised to see a 2 deg current

They made a video on that ~6 months ago

Libby did it better three years ago. Put "bullseye" in the channel's search box.

The props are not going to spin.

Aren't the props not even installed?

@@litz13 all four props are there.

The props are hard mounted to the turbines and the turbines were locked when she was decommissioned. Even if they weren't, the shafts have probably seized in the 30 years since they moved

Yes there will be

What's locked to prevent sabotage are the access panels to the turbine reduction gears. They did an entire video on the topic. The steering gear is like many of the systems on the ship, electro-hydraulic. Electric motors drive transfer cases, which in turn drive hydraulic pumps. The hydraulic systems that need to drive powertrain in both directions are set up as "A-end/B-end" and use the same principle as the hydrostatic drive found in, among other things, your lawn tractor.

They won't spin during the tow.

In previous trips to Drydock #3 at the Philadelphia Naval Shipyard, New Jersey needed two shifts/bumps to get complete coverage. When USS Missouri was drydocked at Pearl Harbor prior to her service as a museum ship, they devised a blocking plan that only needed one bump, rather than two, but still allowed for full coverage. Since each bump takes 2-3 days and a lot of expensive skilled labor to accomplish, being able to skip a bump would save a lot of money. It's unknown whether New Jersey will be able to execute the one-bump plan in the PNSY drydock, or if the two-bump plan is the only option.

The navy has 3 blocking plans for all their ships for this exact reason. They will probably rotate between them to work on the hull.

Ah I knew they had 2 blocking plans but I didn't know they had 3. Thank you very much sir.

then why isn't Texas Amidships? - Actually the single rudder there - perhaps required the rudder other than Amidships in final approach to the pier. not returning it to Amidships after tied up and before shutdown reflects haste and/ or lack of thought. I highly suspect the hydraulic fluid is still there and pretty close to full. He did not state if the Navy's legal document prohibits doing stuff with the rudder. I say it is NOT worth the effort - is possible - the locking bar show looks as if it can be removed "relative easy" Great video - thank to the researcher on the 2° toward barn door closure.

Can’t be moved with the bracing in place

The navy ships I was on used electric heating elements to cook with. Running a flammable gas system on a warship would be incredibly dangerous if the system was damaged in battle. We had acetylene tanks for cutting and welding onboard that were stored on the weather decks so that a leak was vented outside before it could cause an explosion in the ship.

Why is everyone thinking the screws turn? They don't freely spin.