120 Degree Track?

[Pisces]

Oh, ok then. If the master says he does it like that... But I'm not sure I agree with his reasons.

[Nisgeis]

Here is the fire control manual from the 1950s for fleet boats:

http://www.hnsa.org/doc/attack/index.htm

Thge optimum track angles are shown in plate XVII and plate XVIII. What calculations that graph is based on isn't shown. It appears from the graph though, that for a zero gyro angle shot, the maximum deflection angle you can get is the best.

That graph is a theorhetical example as it's for a zero gyro angle shot with a torpedo run length of 1,000 yards, so it's not something that you could manouver for. So, trying to read that graph as it is is quite hard.

If though you are shooting from behind, the speed of the torpedo will be reduced in relation to the target, which will mean that the target and torpedo have more chance to converge, as the torpedo will spend longer travelling across the target's course so the effective target length is larger. The opposite of the Cromwell method, where the target speed adds to the closing speed.

BUT! That graph is misleding, as you cannot directly compare a shot with a track of 45 degrees and a shot with 120 degrees, as you will need to be in completely different positions to get the same theorhetical 1000 yard run and zero gyro angle. Obviously you will need to be much closer if shooting from behind than if you are shooting from ahead to achieve a 1000 yard run length for both shots and the range difference in the two firing positions will increase the faster the target is.

[Hitman]

EDIT: Removed as I was wrong!

[groomsie]

Please re-read the quote I lifted from the book, posted at 12:22 yesterday.

It is clear that the Wahoo waited as the target passed 90-port to obtain the 120-degree track that Morton felt gave the enemy the least chance to evade. If it were a 60-degree angle as you surmised, they would shoot prior to getting the 90-port angle (as I typically do in SH4).

[EDIT: Removed some verbage to help clarify the thread.] I'll settle for a few links:

http://en.wikipedia.org/wiki/File:FiringGeometry.png (this from the TDC entry shows track angle, although it is listed as "theta subscript track").
http://www.history.navy.mil/library/online/ss-doc-4.htm (see 4107.i).

I think Nisgeis has hit it close to the mark, as that makes some sense. I may need to play around with it on paper and in the game to satisfy myself of how Morton/Wahoo were seeing the problem (and given their success I can't argue, although in the game it very well might be different...).

[groomsie]

I followed the link you gave and found the following on page 8-8 of the manual (pretty much (d) confirmed what Morton apparently did...I'll still need to work out the why...). Check this:

(c) It is within this range of torpedo track angles that the greatest amount of course error can be absorbed. From a study of the curves it is evident that the maximum deflection angle is obtained when firing on the optimum torpedo track angle and that the optimum torpedo track angle has a value equal to 90 degrees plus the maximum deflection angle. It is also evident that as the target speed increases for any given torpedo speed the slope of the curves becomes sharper. This means that the higher the target speed the greater the rate of change of deflection angle with torpedo track angle. It is therefore true that the optimum torpedo track angle is more effective for absorbing errors in course when the ratio of torpedo speed to target speed is large. It therefore may be stated that the optimum torpedo track angle is a good mean torpedo track angle for firing a salvo of torpedoes if the target speed is less than one-half of the torpedo speed.

(d) The optimum torpedo track angle for a 16 knot target for a 46 knot torpedo is about 110 degrees and for a 29 knot torpedo about 125 degrees.

So based on this a 120 track seems reasonable. I would have thought something ahead (Cromwell style) would be best, but I suppose it may not be...

[Hitman]

I'm also trying not to be offended by the assertion I'm not familiar with what track angle means in the US Navy; I may be rusty but I've practiced fire control solutions and fired exercise torpedoes and missiles while serving in the same US Navy. I'll settle for a few links:

Ohhh my bad sorry.

I didn't know your background and thought that it all had an easier answer, please excuse my sillyness. My only justification is that I was trying to help and thought it was easier than it seemed. I'll delete my previous post to prevent confusions for other readers.

Sorry

[Pisces]

Originally Posted by Hitman

Ohhh my bad sorry.

... I'll delete my previous post to prevent confusions for other readers.

Sorry

Trouble is... it still is confusing if you can read the reaction to a 'supposedly bad' post, but not the post itself to make up your own mind. I guess keeping the peace is more important.