The PLAN LCAC Type 726 Yuyi Class

Discussion in 'Navy' started by Jeff Head, Jun 13, 2011.

  1. Tetrach
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    Tetrach Junior Member
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    1-QD-70 is the civilian version based of the QC-70. Can you please quote me the three versions of the QD-70 that your image stated?

    2-The QC-70 gives 7000kw, its civilian version gives 7200kw. That's the only thing you proved.

    3-Yes I was aware that this text proved that it was in not horsepower. that's why I never spoke about this subject again.

    4-I messed up MW and KW from the beginning !
     
  2. lcloo
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    lcloo Junior Member

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    The statement that QC-70 is under power is not correct. No doubt QC-70 has slightly less power than UGT6000 but the weight of the engine has been reduced from 3 ton to 2.3 ton comparing with UGT6000. The new engine has better thrust to weight ratio.

    "功重比明显提升" = Thrust to weight ratio has obviously been improved.

    我国专门进口了乌克兰曙光机械联合体的UGT6000燃气轮机,但在使用中,UGT6000燃气轮机暴露出两大缺点:一是发动机工作时产生强烈低频振动;二是噪声水平高,中国航空工业集团在国产“太行”航空涡扇发动机的基础上,研发出QC-70型燃气轮机。该型机与乌克兰UGT6000燃气轮机相比,虽在最大功率参数上略低,但机体自重轻得多(从3吨减为2.3吨),功重比明显提升,同时彻底根除了低频振动和高噪声两大恶疾。
     
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  3. PiSigma
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    PiSigma "the engineer"

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    7000千瓦 = 7000kW = 9387 HP. So there is a 6% reduction to the Ukrainian 10k HP... But it is also 1/4 lighter. I say QC70 is better. Especially without the vibrational issues.

    Also, in rotating equipment design, the power, mechanical energy of the equipment actually moves along a curve. The values given for turbines, pumps and compressors are actually based on the point of curve where it is most efficient for operation continuously. The maximum power output or mechanical power provided is not normally given, and unless you have the turbine curve, you won't know it.
     
    #733 PiSigma, Aug 10, 2019
    Last edited: Aug 10, 2019
  4. asif iqbal
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    asif iqbal Brigadier

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    So much discussion on LCAC engines

    Getting nowhere

    Anyone got the proof ? Photo says a thousand words
     
  5. asif iqbal
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    asif iqbal Brigadier

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    Another disastrous photo

    Anyone else still believe Type 726 is working ?

    Total shambles now 20 months at JNCX and not moved

    Why waste money on these LCAC ?

    Just scrap them

    [​IMG]
     
  6. Tam
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    Tam Captain
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    Somehow you still think these 726 LCACs are the same ones you saw years ago? Very unlikely.
     
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  7. kickars
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    kickars Junior Member

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    Please, don’t be so negative...

    I personally think they are doing the right thing at the moment. Clearly they are happy with the overall design which must suit PLAN’s requirements well enough. That’s why they are still building and testing them over the years.

    The problem is definitely to do with its engine. It’s a bit like early J-10 and J-11 when they had to use Russian engine since Taihang wasn’t ready then. The difference is that the Russian engines were sufficient enough for PLAAF to operate them. But in this case the Ukraine engines weren’t (but they are just about good enough to test other components).

    So instead of like you suggested stop building and testing them and scrap them all together, China continued with the production to a certainly level and more importantly never stopped testing, even the photo you posted above shows one been piloted out of the dock.

    Why? Simply because China can’t afford to stop and wait for everything to be in place, then starts to design, develop and build them. If you and I think they are 30 years behind the US as it is now, they might be 50 years behind if they waited for the engine. While they have to wait for the engine, there isn’t anything can stop them testing all the other important components which are ready. In fact, I’m sure you agree for such a machine, beside engine there are so many things left to test and refine.

    I mean put it simply, if I’m cooking a full English, while the Mrs is on her way to get a can of baked beans from local supermarket, there’s nothing stopping me to get the hash browns and sausages into the oven at main time.

    That’s how a country like China in fact most developing countries grow and catch up. It is messing, imperfect and against all logic sometimes... The way you described it is also fine. But that’s more like how a developed western country would conduct.

    If you look back a bit more before the age of internet, every project China did was like this. We are so used to how relatively smooth sailing nowadays China develops its big or small projects. But, it only started to happen very recently and we are in luck as we have internet to monitor almost every move.

    That’s why I asked you not to be so negative. Because men and women who worked so hard with limited resources unlike their western counterparts who have shared knowledge and resources deserve our kind word, encouragement, sympathy and most importantly our respect.

    Of cause, you have every right to behave the way you have been. You are not Chinese and you certainly didn’t grow up China. It is probably unfair to ask you have the same feeling towards those men and women or indeed towards China as a whole, as us overseas Chinese or Chinese who still live in China. But maybe, just maybe if/when you take a step back, you might change your tone slightly...
     
  8. Iron Man
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    Iron Man Major
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    Don't bother with asif. He will be forced to eat his words when operational photos finally emerge. It's just a matter of time.
     
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  9. asif iqbal
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    asif iqbal Brigadier

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    I would actually love to do that
     
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