054/A FFG Thread II
- Thread starter tphuang
- Start date
bladerunner
Banned Idiot
Just out of interest sake, why are navy ships painted grey. Why not green , blue, black, pink or yellow and so on, after all military aircraft are?
Dear Goll:
Sometime back you said that one of the main reasons the PLAN has NOT yet built more advanced DDG's (like the 52C's) is because of the lack of a suitable Gas Turbine propulsion plant.
Having worked with ships and being familiar with marine propulsion systems, I can say that modern highly-turbocharged, medium-speed diesel engines have very competitive performance characteristics vs marine gas turbines. About the only factor in which they are inferior is in the power-to-weight ratio.
However in terms of COST, durability, reliability, automation, serviceability, fuel-flexibility (multi-fuel capability - some medium-speed, marine diesels can burn bunker fuels) and particularly - fuel efficiency, the diesels almost always win. Now if I was designing a warship that required considerable range, my first choice as the cruising engines would be a set of medium-speed marine diesels.
In fact, if you work it out, the weight saved with gas turbines, is much less (by orders of magnitude - read factors of 10) than the tonnage of fuel required for long-range cruising given the relative disparities' in the two engines efficiencies. A typical gas turbine has efficiencies around 36% to less than 40%, a marine diesel from 45% to up to 55% (on large, low-speed, engines).
The only reason I would install gas turbines is for emergency or manuevering power - and that as an add-on to the cruise diesels - a CODAG arrangement.
I have a feeling the PLAN is still considering all its options on how to build its next-generation combatant.
Best Regards,
Dusky Lim
Sometime back you said that one of the main reasons the PLAN has NOT yet built more advanced DDG's (like the 52C's) is because of the lack of a suitable Gas Turbine propulsion plant.
Having worked with ships and being familiar with marine propulsion systems, I can say that modern highly-turbocharged, medium-speed diesel engines have very competitive performance characteristics vs marine gas turbines. About the only factor in which they are inferior is in the power-to-weight ratio.
However in terms of COST, durability, reliability, automation, serviceability, fuel-flexibility (multi-fuel capability - some medium-speed, marine diesels can burn bunker fuels) and particularly - fuel efficiency, the diesels almost always win. Now if I was designing a warship that required considerable range, my first choice as the cruising engines would be a set of medium-speed marine diesels.
In fact, if you work it out, the weight saved with gas turbines, is much less (by orders of magnitude - read factors of 10) than the tonnage of fuel required for long-range cruising given the relative disparities' in the two engines efficiencies. A typical gas turbine has efficiencies around 36% to less than 40%, a marine diesel from 45% to up to 55% (on large, low-speed, engines).
The only reason I would install gas turbines is for emergency or manuevering power - and that as an add-on to the cruise diesels - a CODAG arrangement.
I have a feeling the PLAN is still considering all its options on how to build its next-generation combatant.
Best Regards,
Dusky Lim
Blends in with the sea and the sky better. Harder to see with a Mark-4 eyeball in that environment. Naval aircraft in most countries, ones that have to fly over the sea for any significant portion of the time, are typically painted in shades of grey too for the same reason.
The long answer :
"Haze gray and underway" is a common saying in the fleet Navy community. A ships camouflage concealment ability is enhanced and the probability of detection and targeting is reduced by the use of an overall haze gray appearance. For ship color schemes, this reduces the average contrast of the ship to the horizon through the elimination of black and white on vertical or near vertical surfaces above the upper boottopping limit.
bladerunner
Banned Idiot
I would have thought the modern electronic detection and targeting methods would have made the traditional colour schemes redundant. Though I suppose it would still be useful against submarines
bladerunner
Banned Idiot
Surely those coal burning battleships of the late 19th and early 20th century could be easily seen because of the smoke they made?
bladerunner
Banned Idiot
Surely those coal burning battleships of the late 19th and early 20th century could be easily seen because of the smoke they made?
Being seen by the naked eye, or Mk 4 Eyeball is more common, even today, than you would think. Periscopes in the water, low to the water craft, stealthy vessels, etc...where radar has a difficult time, even today.
Same is true in the air for low approaches, and stealthy aircraft.
It would be rediculous to invest a lot of money in low observability from an electronic standpoint and then have your paint scheme give you away.
Navies try to gain every advantage that is there.
Londo Molari
Junior Member
Only when the engines were running full power I'd imagine