Research - please help

[v-i-c-]

I still need good information about destroyer performance (of any WW2 destroyer class).

Especially data about the turning diameter at different speeds would help me a lot.

[Sniper450]

http://en.wikipedia.org/wiki/List_of...ed_States_Navy

no turning radius but there is other info

[sergbuto]

I do not remember exactly but turning radius info/parameters might be in the Destroyer Command/SH2 files. Another possible source of this info might be in files of the PT Boats game (I do not mean encoded but text files in both cases).

[v-i-c-]

Thanks.

Unfortunately I can't use any data from silent hunter.

But somewhere out there must be a book covering that, otherwise the SH guys would just have guessed this data.

[Aktungbby]

Google 'destroyer turning radius' and be amazed!, it was an important issue but in watching the videos of various vessels from destroyers to destroyer escorts the turn diameter at speed is approx. 3x the length of the vessel involved; variances involved putting two rudders on or extending the size of the rudder etc. Good luck

[v-i-c-]

Thank you!

[iambecomelife]

Tactical Diameter for "HMS Codrington", a large flotilla leader-type destroyer built in 1929, was very poor at 980 yards full speed.

For Tribal Class destroyers (built around 1937), this figure was better but still not good at slightly over 800 yards. Like "Codrington", Tribals were large destroyers more suitable for fleet actions than convoy escort.

600 yards at full speed was considered an average figure for destroyer-type ships of this era.

Unfortunately I have not been able to find figures for lower speeds.

[v-i-c-]

Thank you.

[Sailor Steve]

Some American Tactical Diameters (yards/knots).
Wickes: 770/15, 810/25
Farragut: 850/35
Somers: 1240/20, 860/30
Mahan: 870/30
Bagley: 880/30
Sims: 843/30
Benson: 960/30
Gleaves: 700/25
Fletcher: 950/30
Sumner: 700/30
Gearing: 725/30

Destroyer Escorts:
Edsal: 300/20
John C. Butler: 395/25

Because of their extreme length vs beam (fineness ratio) vs rudder size it's a common trait in most ships that they turn better the faster they go, rather than worse as with cars and planes. I have some British numbers stashed away in notebooks, but It will be awhile before I can dig through all of them.

Originally Posted by iambecomelife

Unfortunately I have not been able to find figures for lower speeds.

Unfortunately recording maneuverability at low speed was never much of a priority. They really weren't that concerned with turning capacity at all, as long as they could bring the guns to bear.

[v-i-c-]

Great. If someone else has any data please post, any kind of data (ships, weapons, whatever) will help increasing realism.

[Aktungbby]

In looking up the lengths as listed by Sailor SteveWicks 314 ft; Farragut 341 ft;Somers 381 ft; Edsall 306 ft etc. etc. and their 800-900 yard turning radiuses we're still basically at 3x turning/length at flank/sea conditions give or take as some were modified with double rudders or extended rudders as the war progressed as in my previous post. Accuracy is wonderful but take it easy on yourself...we're dying to play something new! set'm all at 2.88% of their length at 28.77 knots and get on with it. Just make every escort skipper as astute and nasty as ...Johnny Walker! YEAH!

[Sailor Steve]

Originally Posted by Aktungbby

the turn diameter at speed is approx. 3x the length of the vessel involved

If the Wickes class is 314 feet long then by that standard the Tactical Diameter should be 942 feet. In reality it was 810 yards, or 2430 feet, which is 7.74 times the length of the ship.

If the Edsall class DD was 306 feet long and its TD was 300 yards, then yes, it was about 3 times the length.

[Aktungbby]

gotcha! But in watching and thumb nail measuring the videos as per the first post and accounting for all vagaries of WWII: including if the crew has its grog ration, the fighting spirit of the escort captain, additional or upgraded larger rudders, sea conditions etc. etc. the sanity of the modder vs the simplistic joy of the gamer becomes the issue. Throw in doing a 180 in my 65'( no power steering 5 axel) eighteen-wheeler at 25 mph(w/o 'jackin' the cab!), a Catalina 25 or 37 ft Ketch(under motor) and a 18' Grummin canoe with a j or sweep stroke...and 3 x the hull length is an adequate consideration of the matter at hand. I have no way to consider one screw(inboard of the turn radius, in reverse, while the outboard screw is forwarding to warp the turn more tightly... if that can even be practically done. But at least I thought of it.