At ship speeds and turn rates those errors are negligible. They are a factor at aircraft and “fast boat” speeds. Perhaps I could have been more specific. Rather than comply with your request to feed you the answers, I’m going to go out on a limb and assume that you sir, a ship captain with 44 years of experience, possess the ability to research the terms used in my post. Happy hunting.
Seeing as there is no legal requirement for airplanes to have any insurance at all, I would have dragged his ass to the FSDO for that stunt if he made you burn a couple of hours of gas first and THEN checked the paperwork.
Our local CFI examiners were famous for grounding whatever airplane you showed up in, but they did it before you flew. I flew to another state for my ride because of this.
- total thread creep, but I have always wondered at how no one has to actually demonstrate anything for real for a boat/ship license. I guess it isn’t practical, well Bill failed the supertanker docking test, sorry about the oil spill, Bill will get right on it.
My input was the result of my curiosity and not intended to question Your statement. My standard reflex action is rather doubt my ability first instead of challenging the others as I follow a simple rule “: if I come to the conclusion I know everything it means I am misinformed”.
Having said that, I have not asked for some answers and/or Your lecture/explanation but for a link/source of info You have provided in order to verify it and if true to learn something.
I had no idea there were magnetic compasses on aircraft but I know there are no anymore magnetic compasses on some types of ships and I discovered that in a bit awkward way talking to a guy who was saying his ship had no magnetic compass at all what I found strange due to SOLAS regs .
He finished my incessant yapping and barking and doubting by simply sending me an International Ship Safety Equipment Cerificate and I had to shut up in to say the least great embarrassment.
44 years is my total sea experience while as ship master it is 2/3ds of the time mentioned . Anyway I will do as per your kind advise and suggestion.
Cheers.
Details attched: dd 01/13/2022
Name:
KL BARENTSFJORD (effective 2011-06)
IMO Number: IMO 9482366
Flag:
Cyprus (effective 2011-06)
Call sign: 5BHC3
MMSI: 209272000
Ship UN Sanction: Not on list
Owning/operating entity under UN Sanction: Not on list
Characteristics
Type:
Platform Supply Ship (effective 2011-06)
Date of build: 2011-06
Gross tonnage: 4,518
Companies
Registered owner:
K Line Offshore AS (effective 2011-06-28)
IMO Company Number 4127655
Nationality of registration Norway
Address Kystveien 14, 4841 Arendal, Norway.
Company status Active
Yes, apologies about the thread creep.The flight was out of Santa Monica Municipal with a GADO. I immediately requested a review from the supervisor who was in the office at the time. He knew who I was and he corrected the visiting examiner’s error on the spot so there was little lost on my part.
As to vessel handling skills I think Grenoble type facilities and simulators are the best we can currently hope for.
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Sorry, I didn’t have a link in mind as I was working from memory.
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FYI - Magnetic compasses are enormously difficult to use in aircraft. The turning errors that are trivial at boat speeds become huge. The way we use them normally is to make sure the gyrocompass is still set correctly every so often while flying straight and level.
We all have been tested on using them if the gyrocompass fails, but it is not real fun to do it for real.
If you never fly in bad weather, you do not legally have to have a gyrocompass. The trick then to making turns is look outside at where you want to turn to, make the turn, and then check against the compass. You hold course by picking a target far ahead, not be looking at the compass constantly. Pretty much the same for boats/ships if you have anything to see, you can steer 10 times better looking at some landmark miles ahead then head down staring at the compass.
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Examples of acceleration/deceleration and turning errors which require the ability to make instant compensations during precise maneuvers:
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If you look at sth long enough , there is always something to be seen.
From original pic :
Above is OK
But in case of deceleration :
If that is the way pilots think then may be the case of flight AF 447 (2009) should be revisited.
When i drive a car and my coffee cup is not covered then with V= const. nothing spectacular happens.
If I press the pedal to the metal the contents of the cup ends on back seat.
If anything is left and i decide to hit the breaks then the rest of my coffee ends on front window and designers put the window wipers outside not inside and it is the problem.
According to the original pic i will spill less coffee on my back seat while accelerating then decelerating , which defies my practical experience or to give it more scientific sugar coating 
my empirical "studies " of the problem.
And the precession of the magnetic compass still beats me although i am still searching.
Cheers
Acceleration/Deceleration Error:
- The dip-correction weight causes the end of the float and card marked N (the south-seeking end) to be heavier than the opposite end
- When the aircraft is flying at a constant speed on a heading of East or West, the float and card is level
- When the aircraft accelerates on a heading of East/West, inertia causes the weight to lag, and the card rotates toward North [Figure 5]
- When the aircraft decelerates on a heading of East/West, inertia causes the weight to move ahead, and the card rotates toward South [Figure 5]
- The airspeed changes that are needed to make this noticeable are infrequent
- As soon as the speed of the aircraft stabilizes, the card swings back to its East indication
-
Acceleration/Deceleration Memory Aids:
Acceleration/Deceleration Error
Now You are talking . Told You I am the show me guy
I am surprised to learn that dip is corrected by a weight inn aircraft.
The heeling error instrument used to correct a standard marine compass has a magnetized rod mounted on a pivot with a aluminum sleeve that serves as a counterweight. Taking the instrument to a field, somewhere away from other magnetic influences the aluminum sleeve is adjusted until the needle is level. The compass is removed from the binnacle and the instrument is suspended with the needle in the same plane as the compass card. The bucket is then used to contain magnets of the required pole and distance so the needle in the instrument is again horizontal.
Acceleration errors are not the ones that are annoying, most of the time you are not radically changing speed while flying.
Turning errors are the ones that drive you nuts.
Turning Error
-
The pull of the vertical component of the Earth’s magnetic field causes northerly turning error, which is apparent on a heading of north or south
-
When an aircraft flying on a heading of North makes a turn toward East, the aircraft banks to the right and the compass card tilts to the right
-
The vertical component of the Earth’s magnetic field pulls the north-seeking end of the magnet to the right, and the float rotates, causing the card to rotate toward West, the direction opposite the direction the turn is made
-
When turning from a northerly heading, the compass will initially turn the opposite direction and catch up by due East/West [Figure 4]
-
When turning from a southerly heading, the compass will indicate a turn in the proper direction but will lead the actual heading, slowing down by due East/West [Figure 4]
-
The rule for this error is: when starting a turn from a northerly heading, the compass indication lags behind the turn
-
The rule for this error is: When starting a turn from a southerly heading, the compass indication leads the turn
-
If the turn is made from north to West, the aircraft banks to the left, and the compass card will tilt down on the left side
-
The magnetic field pulls on the end of the magnet that causes the card to rotate toward East
-
This indication is again opposite to the direction the turn is made
-
When an aircraft is flying on a heading of south and begins a turn toward East, the Earth’s magnetic field pulls on the end of the magnet that rotates the card toward East, the same direction the turn is made
-
If the turn is made from south toward West, the magnetic pull starts the card rotating toward West-again, in the same direction the turn is being made
-
Turning Error Memory Aids:
-
New heading: roll-out heading ± latitude - half the bank angle
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Oh Dear.You are so precious!!! We learn as we go THX
I am not sure why this is, it may be that aircraft compasses are so small the magnetic correctors don’t fit.
Note the correction card, I used to fly one plane where turning the landing lights on changed the compass heading about 30 degrees.
Reality is that mag compasses are fitted to aircraft only because the regulations insist on it.
Pilots of small recreational aircraft which lack gyros and even an electrical system use pilotage, an eyeball looks at the ground and compares what they see to a map.
Transport category aircraft and modern multi engine and turbine powered aircraft have multiple gyros, inertial navigation systems, GPS, and remarkably capable positioning systems that have reduced the mag compass to not much more than an obstruction to forward vision.
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You know there is still a whole bunch of us that need the magnetic compass to keep the gyro compass set. We don’t all have glass-panel money
Have you ever looked out the windshield before takeoff and noticed those numbers painted on the runway?
As one who has crossed the US coast to coast and north to south many times in a Champ and open cockpit biplanes with no electrics or radio I can assure you that the mag compass was the least used or useful navigation tool. That applies to my vintage and homebuilt aircraft as well as the transport category aircraft I used to fly.
But we all have eyeballs.
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Reminds me of looking for the nearest strip when the ceiling was getting low plus fog. Landing and using a pay phone, “I’ll be a little late,” 
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Flying IFR, I kind of like to know what direction the plane is pointing. The gyro compass might be good for the whole flight or need adjustment every 20 minutes. Absent a magnetic compass, adjusting it might be a bit of a trick.
I was loving life with a flight director that set itself with a fluxgate until a wire broke somewhere and it started spinning. That made night-imc-dark-and-stormy landing a pain, because I couldn’t NOT look at it, it had the ILS indicators.