Judging AOB by eye - tutorial

joegrundman · 03-31-08, 07:12 AM

AOB 30

At this AOB, the apparent length of the ship is half the actual length. In addition if you now look at the side of the bridge section, you will see in this ship, the corner is about 1/5 to 1/4 the way across, and in a ship with doubled masts, like this one, a small gap has appeared between the different sets of masts

AOB 35

Nevermind that the picture is smaller! The corner of the bridge is now about 1/4 the way across, and the gap between the mast sets has grown

AOB 40

A ship with masts of this kind now shows an even spacing between all the masts at the AOB, and the corner of the bridge is in line with the funnel (clearly this is not a useful marker with split freighters)

you can however say it is approaching 1/3 the way across

AOB 45

Now i'm getting a bit bored of writing comments! For sure this mid range is the most difficult. The gap between the mast sets has become wider than the gaps between the masts, and the corner of the bridge is now under the funnel. the apparent length of the ship is now 7/10 of its actual length.

AOB 50

Now it starts becoming a bit easier again. At 50, you are beginning to see the full length of the ship (actually 3/4 still), and the gap between the mast sets is clearly seen

AOB 55

AOB 60

At this AOB, the corner of the bridge is about half way across the visible bridge

AOB 65

AOB 70

We are now definately seeing more of the side of the bridge than the front, and we are beginning to see the masts "side on"

AOB 75

AOB 80

AOB 85

This is now only very slightly off being exactly perpendicular

predavolk · 03-31-08, 08:01 AM

Wow, nice! I ID AOB visually, so these are some handy tips indeed!

klh · 03-31-08, 08:11 AM

Well done Joegrundman. I find that I almost always overestimate the AOB with my Mark I eyeball. This will help tremendously!

Have you considered putting this into a pdf? This is something I would love to laminate and keep handy.

ktrboston · 03-31-08, 08:27 AM

Great job Joegrundman! this is a help full post. I also use the Submarine Course finder it is an invaluable tool. I always use because it has so many uses. It is a must have for all Captains.

Laufen zum Ziel · 03-31-08, 10:50 AM

Great stuff. Many thanks for all the things you have given me and the community.

http://silent-hunter-addict.com

Sailor Steve · 03-31-08, 10:53 AM

Thanks, Joe! A great tool. I copied it all and will use it to learn.

Pikes · 03-31-08, 11:36 AM

OMG the middle ranges are hard!

Can i add some "references" please that you may consider?

1. Funnel smoke... It trails more at 90 and is straight at 0. In your picture it wasnt so clear but brings me on to...

2. Wake... in the same way you brilliantly identified the bow, the stern appearance shows more and more. Depending on boat of course, but oval hulls give a lot more away after 20 deg. the trailing wake appears around 75 degrees. Unfortunately your images are still and smoke and wake move so not as easy to tell from still, but wakes are awesomely useful for nightime since they glow more.

3. Flat straight surfaces! Search for a flat panel, the most obvious and useful is the highly visible bridge, but also consider cargo containers which are nice and square. You get nice rectangular patterns that your eye can use when looking at the front "face". These are most useful in the lead up to 90 degrees when the ability to see right across the front of the ship gets closer and closer to 90. Its the same as using the masts although i find that unless you know the masts inside-out they can appear so confusing, esp from a distance. (Hands up who hates merchant masts?!)

4. Any protrusions, bilateral differences, distinctive features... For example the bridge on that illustrated ship sticks out either side. That sticky out point is useful at angles closer to 0. Personally i hate any military ships as the superstructures are so complex and there are lots of rounded parts. coupled with the fact that textures dont reflect the light as well as real objects its harder.

5. Finally i had a ponder about 35-55 degrees. I cant think of a single facet that could make this easier. Anyone getting these is either a genius on their ship recog or using the pause button! The one thing you dont have to help is height. As far as i can guess the best way remains with seeing more than one mast and knowing the distance between them. In truth AoB is all about horizontal distances in the same way that range is to vertical distances. If you knew the length of the ship at 90 and measured it at any angle theres some maths that can give you your AoB.

...I r not mathematizian. :p

PS...the maths bit would require very accurate measurement of the length and require very accurate range to convert your measurement from view to real size and would be innaccurate for AoB 0-20 and 70-90 as wouldnt account for the width. It would also be a huge waste of time and completely pointless when you should be getting other things done as AoB changes. :P

Elmer Kosterman · 03-31-08, 01:50 PM

You've certainly put some work into this, Joegrundman. Can you say something about how well these tips work on other ships? I haven't really studied it, but I'd have guessed that different ships have different spaces between masts, cranes at diffeent angles, different pilothouse-face-ratios, hull curvatures, etc. This could limit the applicability of some of your tips across different ship-types.

Thanks a lot for the tip about apparent ship-length being one-half at thirty degrees. I always thought it was at forty-five degrees, but you reminded me of high school geometry and tangent 30° = 0.5.

This leads me to questions about AOB when a target is maneuvering evasively. Has anyone noticed if the period of swerves is constant in game, and if so, how long it is? When's the best time to fire a torpedo at a swerving target? So that the programmed AOB matches the actual AOB at torpedo impact? Or maybe so that the programmed AOB matches the average actual AOB while the torpedo is in the water?

03-31-08, 07:12 AM	#1
joegrundman Ocean Warrior Join Date: May 2007 Posts: 2,689 Downloads: 34 Uploads: 0	AOB 30 At this AOB, the apparent length of the ship is half the actual length. In addition if you now look at the side of the bridge section, you will see in this ship, the corner is about 1/5 to 1/4 the way across, and in a ship with doubled masts, like this one, a small gap has appeared between the different sets of masts AOB 35 Nevermind that the picture is smaller! The corner of the bridge is now about 1/4 the way across, and the gap between the mast sets has grown AOB 40 A ship with masts of this kind now shows an even spacing between all the masts at the AOB, and the corner of the bridge is in line with the funnel (clearly this is not a useful marker with split freighters) you can however say it is approaching 1/3 the way across AOB 45 Now i'm getting a bit bored of writing comments! For sure this mid range is the most difficult. The gap between the mast sets has become wider than the gaps between the masts, and the corner of the bridge is now under the funnel. the apparent length of the ship is now 7/10 of its actual length. AOB 50 Now it starts becoming a bit easier again. At 50, you are beginning to see the full length of the ship (actually 3/4 still), and the gap between the mast sets is clearly seen AOB 55 AOB 60 At this AOB, the corner of the bridge is about half way across the visible bridge AOB 65 AOB 70 We are now definately seeing more of the side of the bridge than the front, and we are beginning to see the masts "side on" AOB 75 AOB 80 AOB 85 This is now only very slightly off being exactly perpendicular __________________ "Enemy submarines are to be called U-Boats. The term submarine is to be reserved for Allied under water vessels. U-Boats are those dastardly villains who sink our ships, while submarines are those gallant and noble craft which sink theirs." Winston Churchill Last edited by joegrundman; 03-31-08 at 08:08 AM.

03-31-08, 08:27 AM	#4
ktrboston Gunner Join Date: Jul 2007 Location: quincy, ma Posts: 100 Downloads: 8 Uploads: 0	Great job Joegrundman! this is a help full post. I also use the Submarine Course finder it is an invaluable tool. I always use because it has so many uses. It is a must have for all Captains. __________________ Kapitan Clauus on a 5 day shakedown patrol. New crew, new Kapitan waiting for results. Using GWX 3.0

03-31-08, 10:50 AM	#5
Laufen zum Ziel Eternal Patrol Join Date: Jan 2008 Location: Hiding on the bottom Posts: 1,783 Downloads: 853 Uploads: 457	Great stuff. Many thanks for all the things you have given me and the community. http://silent-hunter-addict.com __________________ RIP Laufen zum Ziel

03-31-08, 10:53 AM	#6
Sailor Steve Eternal Patrol Join Date: Nov 2002 Location: High in the mountains of Utah Posts: 50,369 Downloads: 745 Uploads: 249	Thanks, Joe! A great tool. I copied it all and will use it to learn. __________________ “Never do anything you can't take back.” —Rocky Russo

03-31-08, 08:01 AM	#2
predavolk Weps Join Date: Feb 2008 Posts: 369 Downloads: 0 Uploads: 0	Wow, nice! I ID AOB visually, so these are some handy tips indeed!

03-31-08, 08:11 AM	#3
klh Der Alte Join Date: Jan 2002 Location: Indiana, USA Posts: 227 Downloads: 200 Uploads: 0	Well done Joegrundman. I find that I almost always overestimate the AOB with my Mark I eyeball. This will help tremendously! Have you considered putting this into a pdf? This is something I would love to laminate and keep handy.

03-31-08, 11:36 AM	#7
Pikes Seaman Join Date: Oct 2007 Location: UK Posts: 40 Downloads: 42 Uploads: 0	OMG the middle ranges are hard! Can i add some "references" please that you may consider? 1. Funnel smoke... It trails more at 90 and is straight at 0. In your picture it wasnt so clear but brings me on to... 2. Wake... in the same way you brilliantly identified the bow, the stern appearance shows more and more. Depending on boat of course, but oval hulls give a lot more away after 20 deg. the trailing wake appears around 75 degrees. Unfortunately your images are still and smoke and wake move so not as easy to tell from still, but wakes are awesomely useful for nightime since they glow more. 3. Flat straight surfaces! Search for a flat panel, the most obvious and useful is the highly visible bridge, but also consider cargo containers which are nice and square. You get nice rectangular patterns that your eye can use when looking at the front "face". These are most useful in the lead up to 90 degrees when the ability to see right across the front of the ship gets closer and closer to 90. Its the same as using the masts although i find that unless you know the masts inside-out they can appear so confusing, esp from a distance. (Hands up who hates merchant masts?!) 4. Any protrusions, bilateral differences, distinctive features... For example the bridge on that illustrated ship sticks out either side. That sticky out point is useful at angles closer to 0. Personally i hate any military ships as the superstructures are so complex and there are lots of rounded parts. coupled with the fact that textures dont reflect the light as well as real objects its harder. 5. Finally i had a ponder about 35-55 degrees. I cant think of a single facet that could make this easier. Anyone getting these is either a genius on their ship recog or using the pause button! The one thing you dont have to help is height. As far as i can guess the best way remains with seeing more than one mast and knowing the distance between them. In truth AoB is all about horizontal distances in the same way that range is to vertical distances. If you knew the length of the ship at 90 and measured it at any angle theres some maths that can give you your AoB. ...I r not mathematizian. :p PS...the maths bit would require very accurate measurement of the length and require very accurate range to convert your measurement from view to real size and would be innaccurate for AoB 0-20 and 70-90 as wouldnt account for the width. It would also be a huge waste of time and completely pointless when you should be getting other things done as AoB changes. :P

03-31-08, 01:50 PM	#8
Elmer Kosterman A-ganger Join Date: Jul 2007 Location: München Posts: 71 Downloads: 3 Uploads: 0	You've certainly put some work into this, Joegrundman. Can you say something about how well these tips work on other ships? I haven't really studied it, but I'd have guessed that different ships have different spaces between masts, cranes at diffeent angles, different pilothouse-face-ratios, hull curvatures, etc. This could limit the applicability of some of your tips across different ship-types. Thanks a lot for the tip about apparent ship-length being one-half at thirty degrees. I always thought it was at forty-five degrees, but you reminded me of high school geometry and tangent 30° = 0.5. This leads me to questions about AOB when a target is maneuvering evasively. Has anyone noticed if the period of swerves is constant in game, and if so, how long it is? When's the best time to fire a torpedo at a swerving target? So that the programmed AOB matches the actual AOB at torpedo impact? Or maybe so that the programmed AOB matches the average actual AOB while the torpedo is in the water?