Ship Simulator

English forum => Ship Simulator 2008 => General discussions => Topic started by: ACR on October 29, 2007, 16:07:08

Title: Red Jet 4 too fast?
Post by: ACR on October 29, 2007, 16:07:08

hi!

i,m trying pretty hard to get good control of the red jet 4 for achieving fun with these HSC.

now i also saw that the red jet 4 seems to be too fast. at full power and calm sea i can easily go about 42 knots, a little to fast for a commercial catamaran. red funnel claims a speed of 35 knots at 85%, in the sim it goes here pretty faster (37-38) . about 38 knots should be the top speed of this catamaran with service speeds of about 35. can i edit the top speed of this ship somewhere?

thanks much!

Title: Re: Red Jet 4 too fast?
Post by: Alex201 on October 29, 2007, 17:32:36

Less throttle?  :)

Title: Re: Red Jet 4 too fast?
Post by: Bottman on October 29, 2007, 17:39:39

Maybe it's the top trial speed, reached under the yards command shortly before delivery to Red Funnel... ;)

Title: Re: Red Jet 4 too fast?
Post by: lester on October 29, 2007, 21:46:33

I'd agree with Bottman here, Most vessels have several maximum power quotes for the engines and top speeds relative to these power. the 85% power rating is known as Continuous Service rating this is the design running power of the vessel to provide best power to wear ratio. 100% would be the Maximum Continous Rating this as im sure you've guessed is the highest power setting the engines can be safely run at continously. There is also an overload rating at which the engine can only run for short periods before sustaining perminant damage, this is perhaps the figure used in the red jet 4 at full power hence would also be the figure quoted by the yard before delivery.

sorry about the class folks but sometimes its nice to get a bit of back ground ;)

Title: Re: Red Jet 4 too fast?
Post by: ACR on October 29, 2007, 21:49:36

well gentlemen, maybe ;D

without joking, is somewhere a possibility to adjust the top speed? of course its not a big glitch in a very enjoyable game, but this would add some realism to real values

Title: Re: Red Jet 4 too fast?
Post by: ACR on October 29, 2007, 22:02:24

hi lester! you are pretty right but searching the net a little gives us the information the red jet is equipped with two MTU V12 4000 M70 engines rated at 1740KW each. when you look at the mtu homepage this engines are already approved for continious operation at this power range. you can get the same engines also with a little above 2000KW each, but then only approved for short time periods at full power (like you said) .

when i understand right modern engines like these are offered in different power ranges by the manufacturer due to the work they will do and the engines here are the "commercial" version designed fo continious operation at rated power, so it seems the "overload" condition is cut out here by mtu for maximum engine life.

but like said, i,m not sure here.

Title: Re: Red Jet 4 too fast?
Post by: lester on October 29, 2007, 23:26:15

I have to admit it its unusual for commercial vessels to make use of the overload state, it most commonly used in military application. How ever I have since done a little tinternet browsing myself and North West Bay Ships that built red jet 4 quote on thier site a speed range of 38.1 - 41 kts, dependent of the load condition of the vessel (38.1 kts for full deadweight and 41 kts for lightly loaded both at 100% MCR).

http://www.nwbs.com.au/net/39.html

So in answer to your origiinal question the top speed could do with coming down a knot or so but I have no idea how you do that, its the bit of simming I'v always been bad at :(

P.S ACR your understaning is perfectly correct, im glad someone understands my techno-babbel (I often dont!)  ;)

Title: Re: Red Jet 4 too fast?
Post by: Eemspoort on October 30, 2007, 09:09:22

Don't worry, your techno-babbel is pretty clear. ;)

Now, for the top-speed of the RedJet4. I wouldn't worry about those few knots, ACR. All depands on more conditions then hull and engine alone. If the water is calm, you will get better speeds. If the air is cool, the engine will deliver (slightly) more HP then when the air is warm. And so on, and so on.

With these kind of fast ships, its fairly easy to gain or lose a few knots deu to weather and water conditions.
So, i wouldn't call this a glitch or bug, rather then a positiv intrepetation of the RedJet4. ;)

Title: Re: Red Jet 4 too fast?
Post by: ACR on October 30, 2007, 23:32:15

hi!

yes i also read not from the manufacturer that the der jet4 reached 38-41 knots at trial. but i think the trials are made with very light load and calm sea, good athmosperic conditions etc. and are a benchmark the vessel cannot reach at everyday service. in the sim i can reach over 42 knots simulatin "everyday business"

like said, i would prefer to see the top speed at about 37-38 knots to reach speeds of 33-35 knots at normal operations.

but indeed its an minor glitch and maybe a small suggestion for vstep to adjust this since searching here the forums it semms impossible to edit any ship caracteristics in SS08.

thank you all for your information and help!