Matrix Games Forums

Forums  Register  Login  Photo Gallery  Member List  Search  Calendars  FAQ 

My Profile  Inbox  Address Book  My Subscription  My Forums  Log Out

Seastates

 
View related threads: (in this forum | in all forums)

Logged in as: Guest
Users viewing this topic: none
  Printable Version
All Forums >> [New Releases from Matrix Games] >> Command: Modern Air / Naval Operations >> Seastates Page: [1]
Login
Message << Older Topic   Newer Topic >>
Seastates - 8/31/2017 2:03:41 PM   
kch

 

Posts: 134
Joined: 12/31/2014
Status: offline
hi.. Just a quick question on weather. Does the sea state affect the ship speed and sensor and weapon performance? I realise that this probably much more important before the missile age, but I would still expect smaller vessels to suffer significant speed and performance issues in high wind
Post #: 1
RE: Seastates - 8/31/2017 3:15:28 PM   
USSInchon

 

Posts: 40
Joined: 2/17/2014
Status: offline
I don't think it does, I have experimented with it and found that even if the sea state is exceeded nothing happens. The ship will maintain flank speed indefinitely without issue.

(in reply to kch)
Post #: 2
RE: Seastates - 8/31/2017 3:26:41 PM   
thewood1

 

Posts: 4007
Joined: 11/27/2005
Status: offline
Page 107 in the manual and through out the addendum and FAQ are comments on weather effects, including stability for gunnery.

(in reply to USSInchon)
Post #: 3
RE: Seastates - 8/31/2017 4:57:06 PM   
AlphaSierra

 

Posts: 132
Joined: 2/13/2017
Status: offline
In real life it sure does, more sonar than Radar, wind plays havoc with larger ships. Sea states around 5 or 6 can slow smaller ships. I have seen 30ft waves over the deck and that's 80ft from the waterline!

In the Simulator not as much of an effect as it could be. A smaller ship would delay leaving port in a 5 or 6 seastate for instance.

Large ships would drive the tugs into the breakwater over 20 to 25 knots of wind (hard to keep them on course through narrow channels)

_____________________________

I wish to have no connection with any ship that does not sail fast; for I intend to go in harm's way. -John Paul Jones

(in reply to kch)
Post #: 4
RE: Seastates - 8/31/2017 8:36:09 PM   
apache85

 

Posts: 1397
Joined: 12/18/2014
From: Melbourne, Australia
Status: offline
In game weather does affect sonar and radar, sonar is affected by sea state and I think rainfall. Radar is affected by rainfall but not sure about sea state. Sea state has a fairly marked effect on gunnery accuracy but doesn't seem to slow anyone down from my observations.

As AlphaSierra says above, in peace time most ships would try to flee from sea state >5, even in war time probably not much is going to get done on anything FFG - CG sized above sea state 6, from personal experience nearly everyone will be too sick to function.

Edit: Coincidentally the ship I'm on right now is fleeing a storm that will bring SS 5 & 6

< Message edited by apache85 -- 9/1/2017 8:03:06 AM >

(in reply to AlphaSierra)
Post #: 5
RE: Seastates - 9/3/2017 1:27:50 AM   
OldSarge


Posts: 301
Joined: 11/25/2010
From: Albuquerque, NM
Status: offline

quote:

ORIGINAL: apache85

In game weather does affect sonar and radar, sonar is affected by sea state and I think rainfall. Radar is affected by rainfall but not sure about sea state. Sea state has a fairly marked effect on gunnery accuracy but doesn't seem to slow anyone down from my observations.

As AlphaSierra says above, in peace time most ships would try to flee from sea state >5, even in war time probably not much is going to get done on anything FFG - CG sized above sea state 6, from personal experience nearly everyone will be too sick to function.

Edit: Coincidentally the ship I'm on right now is fleeing a storm that will bring SS 5 & 6


Latouche-Treville in stormy seas You won't be landing a chopper on her pad.

(in reply to apache85)
Post #: 6
RE: Seastates - 9/3/2017 8:41:31 AM   
Gunner98

 

Posts: 3992
Joined: 4/29/2005
From: The Great White North!
Status: offline
Not so sure about that. This Sea King is using the Beartrap haul down system.

https://www.youtube.com/watch?v=5p1xx0ysfeM

Scary stuff.

B

(in reply to OldSarge)
Post #: 7
RE: Seastates - 9/3/2017 8:14:32 PM   
apache85

 

Posts: 1397
Joined: 12/18/2014
From: Melbourne, Australia
Status: offline
Yep, we used RAST in the RAN and had the capability--although often not the will--to recover helos in very high sea states. From an operational perspective however it was very unlikely a helo would be launched in those conditions, I recall even with a fairly urgent medical emergency on board our CO wouldn't authorise a helo launch in SS 5, instead we made a 12 hour dash back to port.

(in reply to Gunner98)
Post #: 8
RE: Seastates - 9/4/2017 1:47:48 PM   
kch

 

Posts: 134
Joined: 12/31/2014
Status: offline
Since you guys seem to know what you are talking about, what sea state would the following be?

https://www.youtube.com/watch?v=s1XaZ-EVGkg

(in reply to apache85)
Post #: 9
RE: Seastates - 9/5/2017 12:36:56 AM   
apache85

 

Posts: 1397
Joined: 12/18/2014
From: Melbourne, Australia
Status: offline
Seastate looks like 5 or maybe 6, the main issue is that's quite a small ship and it is bobbing around like a cork. It seems like the ship was initially beam on to swell (hence the huge roll early in the video) and then made a course change into the swell/wind to complete the landing.

To be clear though I am not a seamanship specialist, there would be other people about who know much more about this.

(in reply to kch)
Post #: 10
RE: Seastates - 9/5/2017 9:20:49 AM   
kch

 

Posts: 134
Joined: 12/31/2014
Status: offline
hats off to the people involved in the video. Very calm

(in reply to apache85)
Post #: 11
RE: Seastates - 9/6/2017 2:26:08 AM   
CV60


Posts: 706
Joined: 10/1/2012
Status: offline
quote:

Since you guys seem to know what you are talking about, what sea state would the following be?

https://www.youtube.com/watch?v=s1XaZ-EVGkg



I believe the ship is a Knud Rasmussen class patrol vessel [ https://en.wikipedia.org/wiki/HDMS_Ejnar_Mikkelsen_(P571) ] and was apparently shot as part of a test to determine the landing limits of the Lynx helo [ http://www.businessinsider.com/lynx-helicopter-landing-in-rough-seas-2016-5 ]. I couldn't find a description of the sea state when this video was shot. My guess is that this is in sea state 7. The Knud Rasmussen is 72m length overall, with a draft of 4.95m (hence the rolling in the video). Taking a screenshot of the video from a nearly abeam position, I show the LOA as 560 pixels, which translates to 0.128 meters/pixel. See attached. The height of the main deck/forecastle over the waterline appear to be about 50 pixels, or 6.4 meters. In the next photo, the wave (peak to trough-see white arrow) appears to be 90 pixels tall, or approximately 11.5 meters (actually more, due to the peak being further away). However, this may have been an unusually large wave, as that would put this in the sea state 9 category. The foam from breaking waves is beginning to be blown in the direction of the wind, but it is less pronounced than at sea state 8.




Attachment (1)

< Message edited by CV60 -- 9/6/2017 10:32:17 AM >

(in reply to kch)
Post #: 12
RE: Seastates - 9/6/2017 3:13:59 AM   
AlphaSierra

 

Posts: 132
Joined: 2/13/2017
Status: offline
3 or 4

Beaufort Sea States

I'm not sure when it was "decided" or Why some descriptions go past 6

< Message edited by AlphaSierra -- 9/6/2017 3:24:03 AM >


_____________________________

I wish to have no connection with any ship that does not sail fast; for I intend to go in harm's way. -John Paul Jones

(in reply to kch)
Post #: 13
RE: Seastates - 9/6/2017 4:47:02 AM   
apache85

 

Posts: 1397
Joined: 12/18/2014
From: Melbourne, Australia
Status: offline
Perhaps I'm ignorant but on all the ships I've worked on the Beaufort scale has gone to 12? I actually just went to the bridge to check, and it does indeed go to 12.

The document you link to is from a whale watching group and is prefaced with words to the effect of 'it's not worth whale watching above sea state 4' and then 'here's a description of sea state 0-6'. Maybe that's where the confusion comes from?

The Beaufort scale is actually a scale of wind speed, it is often translated/approximated to a wave intensity scale of 0-9 because wind and waves are closely related in the open ocean. There are a few different scales going around for waves, but the thing they all have in common is a degree of subjectivity, as it is basically impossible to measure a wave at sea and different people will have different estimates.

Like I said, I am not an expert on seamanship so I could be wrong, but this is the first I've ever heard of the Beaufort scale only going to 6.

One thing is certain though, that little patrol boat is in rough seas.

(in reply to AlphaSierra)
Post #: 14
RE: Seastates - 9/6/2017 10:27:47 AM   
CV60


Posts: 706
Joined: 10/1/2012
Status: offline
quote:

3 or 4

Beaufort Sea States

I'm not sure when it was "decided" or Why some descriptions go past 6

< Message edited by AlphaSierra -- 9/6/2017 3:24:03 AM >


As apache85 noted, the Beaufort scale goes to 12 ( https://en.wikipedia.org/wiki/Beaufort_scale ) .

(in reply to AlphaSierra)
Post #: 15
RE: Seastates - 9/6/2017 11:21:33 AM   
AlphaSierra

 

Posts: 132
Joined: 2/13/2017
Status: offline
The sea state used in the sim is accurate and adequate.

_____________________________

I wish to have no connection with any ship that does not sail fast; for I intend to go in harm's way. -John Paul Jones

(in reply to CV60)
Post #: 16
Page:   [1]
All Forums >> [New Releases from Matrix Games] >> Command: Modern Air / Naval Operations >> Seastates Page: [1]
Jump to:





New Messages No New Messages
Hot Topic w/ New Messages Hot Topic w/o New Messages
Locked w/ New Messages Locked w/o New Messages
 Post New Thread
 Reply to Message
 Post New Poll
 Submit Vote
 Delete My Own Post
 Delete My Own Thread
 Rate Posts


Forum Software © ASPPlayground.NET Advanced Edition 2.4.5 ANSI

0.121