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Aerospace Difference b/w Air/Land launched missiles

  1. Sep 28, 2010 #1
    Provided that we have got two different missiles by name(A & B) but yet they have in common the guidance system as well as the engine say a turbofan; can they be called a single missile having two versions i.e air launched & land launched??

    If not does this mean that though both have turbofans but thrust profiles/specific impulses are different for air & land launched missiles??

    I do know that there will be some aerodynamic diffences but what about internal makeup??
     
  2. jcsd
  3. Sep 28, 2010 #2
    If the two missiles, you are talking about, are made by the same company then they can be considered a single missile with two versions.
     
  4. Sep 28, 2010 #3
    Missiles don't use turbofans, they use turbojets.
     
  5. Sep 28, 2010 #4

    minger

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    I've seen long-range missiles with small bypass ratio turbofans.

    Aside from that, they could be, but obviously the start sequences will be different. More importantly though, air and surface-launched missiles typically have different missions, and thus aren't suited for the same missile.

    It's difficult enough at times to design for one operating point and condition, let alone two different missions.
     
  6. Sep 28, 2010 #5

    russ_watters

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    I'd say the biggest difference is a surface launched cruise missile often requires a rocket booster.
     
  7. Sep 28, 2010 #6

    boneh3ad

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    Um... Cyrus, what about Tomahawks? AGM-86? AGM-129? Basically any cruise missile will use a turbofan.
     
  8. Sep 28, 2010 #7
    I thought those were turbojets. Interesting....must be low bypass ratio.
     
  9. Sep 28, 2010 #8

    boneh3ad

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    Low-bypass turbofans. There aren't any turbojets used on any American aircraft these days that I am aware of. I am not even sure if other countries still use them. Even fighters use low-bypass turbofans now. Generally, missiles use either a turbofan or a solid rocket engine depending on their mission.

    To answer the original question, you can have the same missile that is capable of both air and sea (and land) launches. For example, the Tomahawk could launched from land or sea (though we no longer use the land version) and was designed to be able to launch from the air if needed. It uses a solid rocket to launch and then the turbofan kicks in regardless of the launch method.
     
  10. Sep 28, 2010 #9
    People I believe ht there must be some difference in thrust profiles of a cruise missile that is launched from a aircraft fling at
    1) 1.6Mach
    2)~16km altitude

    compared to a missile launch from sealevel with 0 initial speed
     
  11. Sep 28, 2010 #10

    berkeman

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    Did you see russ' comment in Post #5?
     
  12. Sep 28, 2010 #11

    russ_watters

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    Some clarifications:
    -It isn't typical for cruise missiles to be launched from supersonic aircraft.
    -Some cruise missiles use turbojets, notably the Harpoon family: http://en.wikipedia.org/wiki/Boeing_AGM-84_Harpoon
    -Supersonic cruise missiles aren't all that common, but tend to use rocket-boosted ramjets.
    -Yes, the point of the rocket booster is essentially to boost the cruise missile from a standing start into the the launch envelope (a certain speed and altitude) of the air-launched version. This, of course, requires a high thrust for a short period of time.
     
  13. Sep 29, 2010 #12
  14. Sep 29, 2010 #13

    jhae2.718

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    The AGM-129 and BGM-109 are different cruise missiles.
     
  15. Sep 29, 2010 #14
    Manufacturer General Dynamics (initially)
    Raytheon Missile Systems
     
  16. Sep 29, 2010 #15

    jhae2.718

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    Just because they have the same manufacturer doesn't make them the same missile. The BGM-109 Tomahawk was originally designed as a submarine launched cruise missile. The AGM-129 was intended to be an LO air launched cruise missile with a nuclear warhead. They are different platforms with different missions.
     
  17. Sep 29, 2010 #16

    boneh3ad

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    AGM-129 is also low-observable and has a significantly longer range but could only be launched from a B-52
     
  18. Sep 30, 2010 #17
    Tht was my basic confusion of whether should i take thm two different missiles or a single missile wth two variants??
    BY THE WAY Do you also believe in that perception that only similarly designed missiles can be called as versions of each others...
     
  19. Sep 30, 2010 #18

    jhae2.718

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    In the case of the two missiles above, they are different. There may certainly be some commonalities; somewhat similar guidance and propulsion systems may be used (why reinvent the wheel, after all?). They may be in the same class of missile, but they are different platforms, IMO.

    Now, if you were to compare the sea and air launched versions of the Tomahawk, those would be different variants of the same missile.

    Of course, I'm not the person who gets to definitively state these things.
     
  20. Sep 30, 2010 #19
    ^^Thnx now I understood.
     
  21. Oct 5, 2010 #20
    Supersonic cruise missiles do not exist. Supersonic missiles certainly exist, but they're all rockets, from the relatively small and short-range Mach 2.5 Aim-9 Sidewinder to the medium-range AIM-54 Phoenix and the old B-52 http://en.wikipedia.org/wiki/Short-Range_Attack_Missile" [Broken]to long-range ICBMs.
     
    Last edited by a moderator: May 5, 2017
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