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Thread: Sukhoi T-50 PAK FA

  1. #6436
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    Quote Originally Posted by void View Post
    Thrust loss for flat engine nozzles vs cylindrical can be as low as 5% supposedly for modern designs, according to some statements from Saturn and Salyut I've read.
    if that was the case why don't we see any flat nozzles in the world????

    dude in a engine having a conical nozzle the efficiency can reach a disproportional high of 90% even if the compressor and turbine efficiency are only 60-70% which no other design can give.

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    Quote Originally Posted by abhishek-nayak View Post
    if that was the case why don't we see any flat nozzles in the world????

    dude in a engine having a conical nozzle the efficiency can reach a disproportional high of 90% even if the compressor and turbine efficiency are only 60-70% which no other design can give.
    Because a flat nozzle only makes sense in a stealth optimised design? Otherwise there is no point since even if the potential thrust loss is small (say 5%), thats still a net loss. The B-2 bomber, F-117, and the F-22 have flat nozzles.

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    Senior Member twinblade's Avatar
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    Quote Originally Posted by abhishek-nayak View Post
    if that was the case why don't we see any flat nozzles in the world????

    You were saying ?

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    Quote Originally Posted by twinblade View Post

    You were saying ?

    i am deeply sorry for the typing error.I wanted to say "[*******#333333]if that was the case why don't we see [/COLOR]many[*******#333333] (not any)flat nozzles in the world????"[/COLOR]

    [*******#333333]i know that flat nozzles are used for scattering radar waves which is a very critical stealth feature.[/COLOR]

    [*******#333333]the bottomline is:-[/COLOR]

    [*******#333333]1) flat nozzle = stealth but lower performance eg F117 [/COLOR]

    [*******#333333]2) conventional nozzle = higher performance but [/COLOR]susceptible[*******#333333] to radar detection eg chengdu j20
    [/COLOR]
    the only exception to the above is the F22

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    Quote Originally Posted by abhishek-nayak View Post
    if that was the case why don't we see any flat nozzles in the world????

    dude in a engine having a conical nozzle the efficiency can reach a disproportional high of 90% even if the compressor and turbine efficiency are only 60-70% which no other design can give.
    Because low observable considerations weren't a priority in design until less than two decades ago.

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    Quote Originally Posted by abhishek-nayak View Post
    if that was the case why don't we see any flat nozzles in the world????
    Because that's the difference between a nation with tremendous research and funding in stealth technology and the wannabes who put some fancy plates on.

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    Quote Originally Posted by Mackie View Post
    Because that's the difference between a nation with tremendous research and funding in stealth technology and the wannabes who put some fancy plates on.

    hehehe.... but dude spending on R&D for a stealth plane is just one part....building,operating and maintaining a 5th gen fighter can make the richest of rich go bankrupt.

    thats why both F22 and F35 programs are facing crisis.

    How many nations can afford a plane that cost more than 100 million $ a piece?? in case of F22 thats 350 million $ per unit.

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    The PA- 50 is going to make an impact. There is technology on both sides of the Atlantic and what the media usually portray as superior to the rest can change in a eye-wink.Technology change as R&D will make profound changes. Watch this space in the near future!

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    Let me repost these





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    Quote Originally Posted by abhishek-nayak View Post
    [*******#333333]i know that flat nozzles are used for scattering radar waves which is a very critical stealth feature.[/COLOR]
    Its not necessary for the nozzle to be flat. Even a Jalebi shaped nozzle will serve the purpose if it reduces thermal and em signature with loss of thrust being within acceptable limits. A "flat" nozzle helps in increasing the surface area of the plume hence reducing its thermal signature, the serrations on the edges are for EM signature management.
    [*******#333333]
    [/COLOR]
    the only exception to the above is the F22
    Yf-23, X-32. X-47b

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    Quote Originally Posted by void View Post
    Thrust loss for flat engine nozzles vs cylindrical can be as low as 5% supposedly for modern designs, according to some statements from Saturn and Salyut I've read.
    Lower than that.

  12. #6447
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    Quote Originally Posted by abhishek-nayak View Post
    hehehe.... but dude spending on R&D for a stealth plane is just one part....building,operating and maintaining a 5th gen fighter can make the richest of rich go bankrupt.
    .
    Not sure what you're smoking but 5th gen fighters are nowhere near expensive enough to bankrupt a country. Not unless you're buying them by the thousands each year.

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    Surely, F-22 was just a gift horse, no other competitors are in the sky. F-35B is comparable to PAK FA in price terms but it's obviously inferior to the russian toy.
    http://www.ausairpower.net/APA-NOTAM-300309-1.html

  14. #6449
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    Quote Originally Posted by xav View Post
    Let me repost these





    very cool Russian air killer

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