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kilcoo316

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  • in reply to: Most maneuverable modern non-TVC fighter? #2537499
    kilcoo316
    Participant

    Like so?

    http://www.its.caltech.edu/~wirz/Seminar/f22_vortex.jpg

    Are you sure it starts using vortex tunnel lift as low as 3deg AoA? Vortex lift is extremely inefficient compared to the normal bound/trailing vortex lift system.

    in reply to: Most maneuverable modern non-TVC fighter? #2537517
    kilcoo316
    Participant

    With that being said I dont see why the Raptor is not equally or more maneuverable in the supersonic regime then the Typhoon; especially if the only source out there that compares the two states that while the EF has a greater instanteous TR the Raptor has the greater sustained TR(they also quote the speed and altitude).

    Elevators are a less efficient way of inducing a nose up pitching moment – you have to generate a downward force to do so – obviously reducing overall lift coefficient. Its also the same with TVC – you are sacrificing overall upwards (‘lift’) force to pitch the nose up.

    [Against that, canards do induce a downwash field over the inner wing to an extent, reducing efficiency – however, the tip vortices off the canards are beneficial at higher AoAs].

    I see absolutely no reason for the F-22 to have a better sustained turn rate except diabolically larger T/W ratios…

    in reply to: Most maneuverable modern non-TVC fighter? #2537582
    kilcoo316
    Participant

    The original spec of the EF was to have an empty weight of 9.75 tonnes.

    Its actual empty weight is somewhere in the region of 11 tonnes.

    The Typhoon’s ratio from that website is the same as presented in the mid/late 90s – I’ll have to double check, but I’m over 95% sure the numbers are identical.

    Also, they are stating the simulated Raptor has A and the simulated Typhoon has B… If you use simulations then you’ll know just how much BS that what they say actually can be!

    in reply to: Most maneuverable modern non-TVC fighter? #2537713
    kilcoo316
    Participant

    Is this fact, or rumour? Can you provide a source?

    As I said – those numbers (kill ratios) haven’t changed in 15 odd years, no change would lead me to believe no updates to the parameters – especially considering the EF being overweight, the F-22 having better than expected cruise capabilities etc etc etc

    Fact – the head of stability and control for the YF-22/F-22 was here about 6 months ago and said so.

    in reply to: Most maneuverable modern non-TVC fighter? #2537762
    kilcoo316
    Participant

    This is where TVC comes into play. Say a combat loaded Raptor of 60000lb and a combat loaded Typhoon of 34300lb were in a supersonic turn. The Raptor would use its 20degree TVC

    And herein lies the common mistake.

    The F-22 does not use TVC dynamically for supersonic manouvering .

    It uses TVC to trim out the aircraft to compensate for the moving aerocentre – giving the elevators their full range of motion and thus increasing manouverability.

    The DERA evaluation you cite was conducted in the early 90s – those numbers haven’t changed.

    in reply to: Most maneuverable modern non-TVC fighter? #2537884
    kilcoo316
    Participant

    I’d say the Eurofighter is one of the most maneuverable in-service fighters that does not have TVC, today.

    But TVC helps in slow and fast speed maneuvering.

    I know what the TVC does for the F-22 in supersonic flight – still won’t stop the EF being more manouverable.

    in reply to: Most maneuverable modern non-TVC fighter? #2539286
    kilcoo316
    Participant

    On the basis of both wing loading, and thrust loading, the Typhoon has the full package. Definitely at the top of my list from a pure agility point of view. The only machine that could consistently out-perform the Typhoon in a close engagement would be the F-22 (which also has thrust vectoring engines).

    In a fast (transonic upward) gunfight – nothing would touch the Eurofighter, not even the F-22. The EF is a much smaller and nimbler machine [there is much more to fighting than T/W]

    In a slow (under 300kts), your looking at the MiG-29, a Flanker derivative (or maybe the F/A-18 if what some on here say is true – I still think its a **** airframe so won’t fully endorse it 😀 ).

    in reply to: F-22 Doing A Cobra Maneuver #2539590
    kilcoo316
    Participant

    Sure, but I only pointed out that it is far more difficult to do it with enderwing stores. From the flight mechanics view.

    It sounds like this:” the Phantom F-4 has enough maneuverability against F-16A to get the job done, considering its other advantages (armament, speed, etc).
    But you would probably preffer to be in F-16A.

    – not really, the cobra is controlled by elevators, so as long as the missiles/pylons don’t screw flow to the elevators you should be ok. The extra drag produced by a few weapons is negligible compared to the drag produced by the wings at AoA 60+.

    Indeed, the chief influence is probably the change to the longitudinal polar moment of inertia. If the elevators can not induce a large enough pitch rate, then the aircraft will flip back down prior to 90deg AoA [due to the wing/elevator nose down pitching moment at extreme AoA].

    – Not really… how reliable was the early sparrows? What does speed do for you in a dogfight?

    in reply to: F-22 Doing A Cobra Maneuver #2539768
    kilcoo316
    Participant

    The F-22 is almost certainly incapable of doing Cobra with underwing stores.

    Regardless of whether the F-22 can or cannot do a cobra with underwing stores, fact is, it doesn’t need to.

    I think the manouverability of the F-22 is enough to get the job done, bearing in mind the other advantages it has.

    in reply to: Bush might Steal space #2539848
    kilcoo316
    Participant

    “Hello McFly, anybody home?”

    http://www.gocarlo.com/lagalerie/images/delorean-profile-512.jpg

    Just back – they were gonna leave a final stage on for manouvering, then decided to build spaceships instead and if they need to nuke someone, do it from there.

    Oh, and just for information, inflation is a bitch…. in 20 years time the price of a pint in the states is 20 euros!!! :diablo: :p 😀

    in reply to: Bush might Steal space #2540330
    kilcoo316
    Participant

    Yeah, ICBMs don’t turn in space. The “hypersonic maneuvering Topal” fantasy works in the atmosphere AFTER reentry. The main reason for his comment I suspect though is that THE ABM SYSTEM IN POLAND ISN’T INTENDED TO INTERCEPT “DOZENS OF TOPOLS”!

    Like it would be so hard to attach a last stage that could manouvre… or to perform manouvering just prior to a normal final stage separation.

    Even if you sacrifice a couple of IRVs or reduce a single warhead’s yeild – so what, better 8 getting through than 12 getting shot down.

    in reply to: Bush might Steal space #2541494
    kilcoo316
    Participant

    Mind educating yourself a little more on what the ABM is designed for !!

    Wishful thinking my friend.

    You know the story of the SR-71 and the eagle “intercept”…

    What happened when the Blackbird guys decided to turn a little? You think it will somehow be different for an ICBM intercept?

    in reply to: Bush might Steal space #2541499
    kilcoo316
    Participant

    But, as Distiller also pointed out, the policy described in the statement is essentially the same policy the US declared under Saint William of Clinton, and no one seemed to have much of a problem with it then. That fact alone suggests (to me, at least) that the current outcry from the Russians, Europeans, et al, has little to do with a genuine concern about the policy’s ramifications — and much more to do with a “let’s oppose everything the US says or does” mentality.

    Does anyone have a link to the Clinton policy?

    Seeing as those comments I highlighted earlier were missed by those who supposedly taken the time to read it, I’d rather read the Clinton policy myself and judge.

    in reply to: Bush might Steal space #2542774
    kilcoo316
    Participant

    Reading the report posted by distiller it says alot more “than things in earth orbit are vital to U.S. interest and that the U.S. will do what it takes to protect their interests.”

    It effectively says the things allowed into earth orbit will be controlled in accordance with US interests.

    The United States considers space capabilities — including the ground and space segments and supporting links — vital to its national interests. Consistent with this policy, the United States will: preserve its rights, capabilities, and freedom of action in space; dissuade or deter others from either impeding those rights or developing capabilities intended to do so; take those actions necessary to protect its space capabilities; respond to interference; and deny, if necessary, adversaries the use of space capabilities hostile to U.S. national interests;

    That bold bit is worrying, and:

    To achieve the goals of this policy, the Secretary of Defense shall:
    Develop capabilities, plans, and options to ensure freedom of action in space, and, if
    directed, deny such freedom of action to adversaries;

    NOTE: Use of adversaries, not enemies. There are subtle differences between adversary and enemy. An adversary is somewhere between competitor and enemy. For instance, the Soviet Union was an adversary of the US during the cold war – not an enemy as they were not actually at war.

    However, against that, this is better:

    The United States considers space systems to have the rights of passage through and operations in space without interference. Consistent with this principle, the United States will view purposeful interference with its space systems as an infringement on its rights;

    in reply to: Bush might Steal space #2542786
    kilcoo316
    Participant

    I’ll explain my problem with that piece posted earlier.

    A new policy recently signed by President George Bush, asserts that his country has the right to conduct whatever research, development and “other activities” in space that it deems necessary for its own national interests.

    The new policy further warns that the US will take those actions necessary to protect its space capabilities “and deny, if necessary, adversaries the use of space capabilities hostile” to those interests.

    What does the interests I’ve highlighted in bold mean?

    The interests of space capabilities, or the national interests?

    If its the former, no problem – if its the latter it opens up a whole can of worms. For instance, Iran starts deploying ELINT or reconsats, does the policy advocate removing them ASAP [before any wars commence – thats what the term deny implies]?

    By the first interpretation it does not – so things should remain… well, peaceful. By the 2nd interpretation, cue killer sats being launched to remove the Iranian machines pronto and quick escalation of any tensions.

Viewing 15 posts - 436 through 450 (of 721 total)