CV-18 Fujian/003 CATOBAR carrier thread

Iron Man

Major
Registered Member
Would not a steam catapult imply steam turbine propulsion?


Would've been nicer if you could've pointed me to a peer-review source. But I did some search of my own. One source I found (1995) claims that steam catapults have an operational energy limit of 95 MJ. The same paper provides a figure with tow force over time, peaking at about 210 kilopounds, or 930 kN. Given a catapult cylinder length of 101m, that comes up to 94MJ, which sounds consistent. Again, taking the 2.8 second launch time, we get 34 MW power for the steam catapult.

For the EMALS the source states a 122 MJ launch energy, or 43.5 MW average power. Now for the actual input power, I couldn't find a clear number. The source mentions that 4 flywheels will be necessary, each with a peak power of 81.6 MW and 121MJ of energy storage. So by that logic, no sane number of gas turbines could meet the instantaneous power requirements.

Compare this to the steam catapult: the authors mention that the steam catapult is only 5% efficient? This would imply 1.9 GJ of required input energy per launch.
"Peer-reviewed" source, seriously? This is the level of evidence you are demanding? Why so high? If I demanded that level of assurance from you I have little doubt you could not say many of the things you are saying now. In any case, like I said, it's all over the internet:
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Max Demian

Junior Member
Registered Member
"Peer-reviewed" source, seriously? This is the level of evidence you are demanding? Why so high? If I demanded that level of assurance from you I have little doubt you could not say many of the things you are saying now. In any case, like I said, it's all over the internet:
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Well, feel free to read for your self:
Doyle, Michael R., et al. "Electromagnetic aircraft launch system-EMALS." IEEE Transactions on Magnetics 31.1 (1995): 528-533.
 
Well, feel free to read for your self:
Doyle, Michael R., et al. "Electromagnetic aircraft launch system-EMALS." IEEE Transactions on Magnetics 31.1 (1995): 528-533.
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Abstract:
With the proliferation of electromagnetic launch systems presently being designed, built, or studied, there appears to be no limit to their application. One of the intriguing applications is electromagnetically catapulting aircraft from the deck of an aircraft carrier. The US Navy had foreseen the substantial capabilities of an electromagnetic catapult in the 1940s and built a prototype. However, it was not until the recent technical advances in the areas of pulsed power, power conditioning, energy storage devices, and controls gave credence to a fieldable electromagnetic aircraft launch system. This paper presents the U.S. Navy's Electromagnetic Aircraft Launch System (EMALS) being developed in partnership with Kaman Electromagnetics (Hudson, MA). It addresses the EMALS's present design and the technologies involved, as well as the ship and operational impacts, advantages, disadvantages, and compatibility issues for today's and tomorrow's carriers.
 

AlyxMS

Junior Member
Registered Member
If you folks want to bring this casual discussion up to the standards of using peer reviewed articles, there's a section in this forum called "Professional Discussions".

Though that section has been abandoned for quite some time, you'll have to cut through layers of spider webs and try not to slip on the dust collected there.
 

Intrepid

Major
However, keep in mind that when launching aircraft, the carrier is operating at near flank speed and in case of QE with IEP would have less spare power available.
Yes, I know. But the propellers are driven by the gas turbines with together 72 MW. The diesel generators are for the auxiliary devices not for the main propulsion system.

Wind over deck for launch (US-Navy rule) should be 40 knots. So flank speed is only needed when the wind is calm.
 

Jeff Head

General
Registered Member
US Navy Review...10-12 years ago.

And these pictures actually show it as it happened back then.

I have seen as many as four CVNs together but cannot find the pics right now...and the six LHDs loaded up for sea control speaks for itself:

000 US CVN Review-01.jpg 000 US CVN Review-02.jpg 000 US CVN Review-03..jpg 000 US LHD Review-01.jpg 000 US LHD Review-02.jpg

I'd love to see the US some time, purely for PR, bring six CVNs together with maybe eight Burke DDGs and four Tico CGs in formation togehter with four Virginia SSNs out front.

Can you imagine such a show?
 

Blitzo

Lieutenant General
Staff member
Super Moderator
Registered Member
US Navy Review...10-12 years ago.

And these pictures actually show it as it happened back then.

I can understand some OT posts of nice pictures...
What annoys me is that Forbin's pictures are CGIs and they don't even show a depiction of 002, but instead shows CV-16 and CV-17 (001A) instead... sigh.
 

Jeff Head

General
Registered Member
I can understand some OT posts of nice pictures...
What annoys me is that Forbin's pictures are CGIs and they don't even show a depiction of 002, but instead shows CV-16 and CV-17 (001A) instead... sigh.
Well, in his defense, the first time we will see a two carrier Chinese Navy formation will be CV-16 and CV-17. CV-18 will come along in terms of an operational picture, several years later.

Certainly by the end of the 2020s we will have a chance of seeing three Chinese carriers together in formation...and I bet we do.
 

Blitzo

Lieutenant General
Staff member
Super Moderator
Registered Member
Well, in his defense, the first time we will see a two carrier Chinese Navy formation will be CV-16 and CV-17. CV-18 will come along in terms of an operational picture, several years later.

Certainly by the end of the 2020s we will have a chance of seeing three Chinese carriers together in formation...and I bet we do.

yes, my point is that the lack of relevance to 002 in the CGI pictures means at best the CGIs should be in the 001A thread rather than the 002 thread.

Not to mention they're old CGIs as well.
 
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