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Thread: Saab JAS 39 Gripen Info # 2

  1. #91
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    Quote Originally Posted by nhampton View Post
    Reality Check


    You are wasting your time Scooter. The answer is right in front of everybody's face.

    accelerated to Mach 1.2 and cut the afterburner

    That is not super cruise by anyone's definition.

    We now return you all to your collective delusions.
    That is the way it is done by the F-22A too.
    Another trick is to do it in a dipsy maneuver and claim it "supercruise".

  2. #92
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    Quote Originally Posted by Scooter View Post
    What makes be laugh is a very dirty "Gripen NG" can Super Cruise and for extended periods with just 7,000 lbs of fuel. (total) Yet, a purely clean F-35 cannot............


    BTW I have never claimed a F-35 with External Fuel and/or Weapons could Super Cruise.
    The problem of the F-35 is the frontal drag, huge wetted area and wing profile to house the fuel.

    For the benefit of the others, it is not the fuel load, but the fuel fraction when it comes to a similar technology level.
    The installed thrust is down to 25% at heights above 36.000 feet, when the generated thrust is from the inlet/outlet-system at supersonic speeds at first.

    Something some will never learn for unknown reasons.

  3. #93
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    Quote Originally Posted by nhampton View Post
    Lets add F-106s, EE Lightnings, F-15s and a host of other jets that can "super cruise" then.
    Okay. If they meet the quite sensible definition of supercruise given then let's.


    Quote Originally Posted by nhampton View Post
    It does not need reheat.
    Are you sure?


    Quote Originally Posted by nhampton View Post
    It can do so with full fuel and warload.
    Are you sure?

    Internal bays remove all that pesky drag but will Raptor be able to do the business with all that mass? And what about when it gets 6 internal AMRAAMS? What will be 'full load' then?


    Quote Originally Posted by nhampton View Post
    I
    It does so at M 1.7-1.9 in all conditions and altitudes.

    Are you sure?

    If so, cool.


    Quote Originally Posted by nhampton View Post
    M1.1 or 1.2 is not much different in reality than M.9.
    Are you sure?

    I think that it is.




    Al

  4. #94
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    Quote Originally Posted by nhampton View Post
    It does so at M 1.7-1.9 in all conditions and altitudes.
    Mach 1.9 SC?!
    In all conditions?!
    All altitudes?!!!!!!!


    Nhampton, less, much less...

    You are not going to find one single tactical fighter who can surpass Mach 1.25/1.3 (i am thinking of the Aardvark or theTornado Fmk3 here) at low altitude with full re-heat.
    Darryl Greenamyers Red Baron F-104, did 1013 mph (mach 1.33) unofficially (faulty timing equipment) at 300 ft AGL back in the '70's.
    If the the TSR-2 had reached the sqn´s, maybe we could have seen a low level mach 1.3/1.4 strike aircraft

    Raptor supercruise at the "famous" Mach 1.72 will be at BINGO altitude and conditions, we are not going to see a F-22 doing that at 1000 meters.
    Actualy, at "Deck" level i wouldnt be surprised if the Raptor was bested by something like a Blackburn Bucaner.

    And before the "Raptor legion" starts throwing stones, yes, i am aware that its completely irrelevant the sea level speed of the F-22.

    Cheers

  5. #95
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    Quote Originally Posted by Scooter
    BTW I have never claimed a F-35 with External Fuel and/or Weapons could Super Cruise.
    Don´t worry the JSF and the F-16IN are perfectly capable of supercruising. (Those CFTs of the F-16IN must be slightly magical?) Need a source? Well here you are...

    http://www.financialexpress.com/news...bility/262072/

    Yet another credible source(for the F-16IN at least):

    http://www.expressindia.com/latest-n...bility/262072/

    Quote Originally Posted by Sintra
    Mach 1.9 SC?!
    In all conditions?!
    All altitudes?!!!!!!!
    I believe the F-22 can SC at mach 1.9 at all altitudes! Need a source? Why?

    Quote Originally Posted by Scooter
    The F414 which is to equip the Gripen NG. Is hardly the most fuel efficient nor is it designed to operate for extended periods at Super Sonic Speeds.
    Isn´t it? What a piece if ****! Still the Gripen apparently is capable of SC, wicked isn´t it? Maybe it´s the testimony of an aerodynamically sound design?
    Last edited by MP703; 12th May 2009 at 21:33.

  6. #96
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    Quote Originally Posted by nhampton View Post
    Lets add F-106s, EE Lightnings, F-15s and a host of other jets that can "super cruise" then.
    Do they make it over the barrier ~M1.07 ?
    the only reason why Super cruise was ever brought up with the F-22 is that it can actually do it in a tactically significant way.
    Junk, or do you want to elaborate ?
    It does not need reheat.
    It can do so with full fuel and warload.
    It does so at M 1.7-1.9 in all conditions and altitudes.
    More junk/trolling, F-22 reaches M1.75 @35.000 ft, then drop off depending on altitude to M1.05. so make that M1.05-1.75, -which btw according to you is useless then.
    Of course it can reach higher speed in a dive, but unfair as it may sound, -so can any aircraft, even non-US made.
    http://www.tailhook.org/RENO%202007%...aptorBrief.ppt
    M1.1 or 1.2 is not much different in reality than M.9.
    In every other evaluation in this world, >10% is considered significant, -why is this particular site any different ?
    the missile will require about five times the G capability of the target to complete a successful intercept.
    -Robert L Shaw

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    Quote Originally Posted by Al. View Post
    Okay. If they meet the quite sensible definition of supercruise given then let's.
    I personally see the sudden hunt for supercruise as pretty comical and this feature as next to meaningless. While much more sophisticated than before, current BVR weapons also have to face much tougher counter-measures (ECM, RCS reduction, IR signature reduction, etc... ) and as such will hardly be more often fired from maximum kinematic ranges, unless you want to accept 20% kill probability like in late 60s.

    If you can't exploit max. range, then kinematic advantage at the moment of firing brings in no decisive effect. Besides that, even F-22 cannot depend on having kinematic advantage all the time, there are much faster aircraft in service, even if it costs additional fuel.

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    @ what speed will the Gripen supercruise with one of these? Or the LCA?

    They just made the super hornet a lot hotter!

    USS.

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    This part look particulary amusing
    "The 'enhanced durability engine' becomes the 'enhanced performance engine' when you put the fan on it," Gower said.
    It looks like it's possible to simply install that fan on it later on, should the need arise.
    the missile will require about five times the G capability of the target to complete a successful intercept.
    -Robert L Shaw

  10. #100
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    Question

    Quote Originally Posted by uss novice View Post
    @ what speed will the Gripen supercruise with one of these? Or the LCA?



    They just made the super hornet a lot hotter!

    USS.


    I was wondering if Boeing had offered the F414 (EDE) to India for the MMRCA?
    F-35 Lightning II

  11. #101
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    Quote Originally Posted by Sens View Post
    That is the way it is done by the F-22A too.
    No Sens that is not how it is done with the F-22. I am not going to do your research but you can go onto another forum and get a first hand account from a named pilot that clearly indicates otherwise.

    It's done in military power. The published max speed without reheat is M1.72 but I happen to know that the true speed is closer to M1.9.

    Assume an enemy fighter is about 200 miles away.
    Given a speed of M1.7@40K the airspeed is 1133mph. M1.2@40K is 790mph. M0.95@40K is 626mph. M0.90@40K is 593mph. Assume 1/2 hour of fuel remains with the throttle set to military power. Assume a tail chase. A 82 mile difference with a 60 mile missile really is not that big a deal. Assume the F-15 that is being pursued is traveling at M0.9 at something less than military power and it likely it out runs our "super cruising" JAS 39. Now take the F-22. The speed difference is 507mph at military/M.95 and 540mph when cruising at M.9. If the F-22 can super cruise for a 1/2 hour then the closing difference is better than 250 miles. Those of you who can grasp the implications will understand. Those that don't, wont. There is a reason why LM says the F-22 super cruises and there is a reason why it may be fun to lower the bar and say that your favorite fighter super cruises but it does not.

    Quote Originally Posted by USS NOVICE
    They just made the super hornet a lot hotter
    Off topic but it is good to see that the most capable and complete fighter in service today continues to be aggressively developed. I find it interesting that despite all of it's supposed performance shortfalls the Navy has chosen to further enhance the reliability and durability of an already very reliable and durable platform. I wonder if they know something some here don't.
    Last edited by nhampton; 13th May 2009 at 04:03.

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    Quote Originally Posted by nhampton View Post
    Lets add F-106s, EE Lightnings, F-15s and a host of other jets that can "super cruise" then.
    Why not? If they can stay super sonic for an extended time (with re-heat or without) they qualify for SC by my definition.
    Quote Originally Posted by nhampton View Post
    The point that a very few on this board get and the majority don't is that the only reason why Super cruise was ever brought up with the F-22 is that it can actually do it in a tactically significant way.

    It does not need reheat.
    It can do so with full fuel and warload.
    It does so at M 1.7-1.9 in all conditions and altitudes.
    Are you serious? The F-22 is one remarkable fighter, but there's no way the above statement is true. Do you have any idea what the aerodynamic heating would do to the airframe if it indeed could do M 1.7 at sea level in +49°C??

    Quote Originally Posted by MP703 View Post
    Don´t worry the JSF and the F-16IN are perfectly capable of supercruising. (Those CFTs of the F-16IN must be slightly magical?) Need a source? Well here you are...

    http://www.financialexpress.com/news...bility/262072/

    Yet another credible source(for the F-16IN at least):

    http://www.expressindia.com/latest-n...bility/262072/
    Any info about what config it will be able to do it in? How many A2A-missiles?

    BTW, the 'other' source, is the same as the first. Just look at the URL.
    Quote Originally Posted by MP703 View Post
    I believe the F-22 can SC at mach 1.9 at all altitudes! Need a source? Why?
    Are you serious as well? See response to nhampton above.

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    There is no such news.

    What scooter or other LM fanboys post is usually not correct.
    Signatory he quoted a credible magazine. ie. Aviation Week as his source.

    As for the Super Cruising F 16 debate.

    Indian newspapers are full of stories (like this one) that Lockheed will offer India an advanced version of the F-16 with supercruise capability. That's the ability to cruise supersonically without reheat and it is a key feature of the stealthy F-22. Well the stories are not quite correct.

    Here's what happened. Lockheed was briefing a group on Indian journalists on the F-16 and one of them asked about supercruise. A helpful test pilot volunteered that he has flown the F-16 supersonically without reheat. The story was born, but can the F-16 supercruise? Not really.

    Lockheed says a clean F-16, with only wingtip missiles, can reach Mach 1.1 without reheat. But the company says supercruise is defined as the ability to fly faster than Mach 1.5, in combat configuration. The USAF's F-22 factsheet suggests it can supercruise at Mach 1.75.
    http://www.flightglobal.com/blogs/gr...percrui-1.html

    I assume that Lockheed has set very high standards to what it defines as 'supercruise' ie. Cruising above 1.5 mach, A clean F 16 may do 1.1 mach and an F 35 'may even do better. But that is still not good enough Super Cruise for Lockheed Martin, hence it is not advertised.

    In India a decade or so ago (before many global players entered the car market) companies advertised things like headrests and seatbelts. The nominal SC of 1.1 - 1.2 being advertised reminds me of that.
    Last edited by ante_climax; 13th May 2009 at 04:22.

  14. #104
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    Quote Originally Posted by TGIF View Post
    Are you serious? The F-22 is one remarkable fighter, but there's no way the above statement is true. Do you have any idea what the aerodynamic heating would do to the airframe if it indeed could do M 1.7 at sea level in +49°C??
    You are correct I wrote badly. I meant to say it can super
    cruise at all altitudes. Not necessarily at M1.7 at sea level.

  15. #105
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    Quote Originally Posted by nhampton View Post
    Off topic but it is good to see that the most capable and complete fighter in service today continues to be aggressively developed. I find it interesting that despite all of it's supposed performance shortfalls the Navy has chosen to further enhance the reliability and durability of an already very reliable and durable platform. I wonder if they know something some here don't.
    Please spare us the most*** and most*** fighter in service and other self-contained definitions, there has been enough marketing around already.

    Regarding the further upgrades of the SH, why not? Navy has already chosen to take this path and crews seem to love the new bird even if it's a bit sluggish. For the record, even baby Hornets never were sports cars so I don't think the crews miss agility that much. SH has excellent low speed maneuvrability and very solid electronics making it a great striker and good BVR performer, nothing more, nothing less.

  16. #106
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    Quote Originally Posted by ante_climax View Post
    ...
    I assume that Lockheed has set very high standards to what it defines as 'supercruise' ie. Cruising above 1.5 mach, ....
    The Lockheed definition is"Whatever F-22 can do that no other fighter can do". Lockheed has changed it in the past, when Typhoon demonstrated that it could meet the previous Lockheed definition. It's a marketing definition.

    This has been gone over many times. As far as I'm concerned, the MiG-31 & SR-70 supercruise(d). Cruise means covering distance efficiently. The point of the F-22s ability to supercruise is not that it does not use afterburner, but that by not using afterburner it is able to fly supersonically for longer than if it did use afterburner. A valuable ability, but if the MiG-31 can fly even further supersonically while afterburning, one can see there's more than one way to skin a cat. There's a confusion between ends & means in many minds. Something is done to achieve a particular aim, & they cannot see that if the aim is achieved by different means, it has still been achieved.

    The F-22, Concorde, etc. supercruise(d) in dry thrust. Same end as SR-70 & MiG-31, different means. And how you get there is irrelevant: what matters is that you get there with enough fuel to maintain the speed for a significant, useful, distance.

    Let's be practical, not dogmatic.

    Quote Originally Posted by ante_climax View Post
    Signatory he quoted a credible magazine. ie. Aviation Week as his source.....
    I can't find a quote from Aviation Week in Scooters posts to support the claim that Gripen can supercruise only with two wingtip AAMs. What I have found is a link to this Flight article.

    The article says nothing about how the Gripen was loaded during the supercruise test. It shows a picture of a Gripen carrying only two wingtip AAMs, but the picture is captioned
    the Gripen Demo (pictured below during an earlier test flight)
    Scooter has, as he has often done before, made claims which are not supported by his source.
    Last edited by swerve; 13th May 2009 at 10:21.
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    Quote Originally Posted by flex297 View Post
    Please spare us the most*** and most*** fighter in service and other self-contained definitions, there has been enough marketing around already.

    Regarding the further upgrades of the SH, why not? Navy has already chosen to take this path and crews seem to love the new bird even if it's a bit sluggish. For the record, even baby Hornets never were sports cars so I don't think the crews miss agility that much. SH has excellent low speed maneuvrability and very solid electronics making it a great striker and good BVR performer, nothing more, nothing less.
    Whats the matter flex you don;t like facts do you? Take for instance your statement on the SH. Yes it has excellent maneuverability especially at low speeds. Given that it has "excellent electronics" and HOBS then it also is an excellent WVR performer as well. Not only that Flex my friend, the radar it is currently flying with is better than any non American radar in service today.

    Hmm I read somewhere that the guy who gets in the first shot probably gets the first kill. This is something that consistently misunderstood by fan boys and trolls like you. It really doe not matter if Super is a bit sluggish in some situations. Given it's electronics and weapons it will consistently detect, track and engage it's adversary before it's adversary can return the favor. It won't matter if it's a thrust vectoring SU-30 with an RCS the size of a barn door, a Eurofrauder with all it's "carefree handling" and DASS or JAS 39NG with it's second hand collection of avionics from a variety of countries parts bin.

    I know this fact is hard on some but the fact that I was born good looking instead of rich is indeed a burden I bear for eternity. We all have crosses to bear. Get over it.

    Nice try AL but I know for a fact my penis is the longest in the world. The fact is some on this forum can make claims without needing a source but others if the claims are not what most want to hear in this venue cannot. Sorry, I am not buying. I cannot reveal sources sometimes.
    Last edited by nhampton; 13th May 2009 at 13:05.

  18. #108
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    Quote Originally Posted by swerve View Post

    I can't find a quote from Aviation Week in Scooters posts to support the claim that Gripen can supercruise only with two wingtip AAMs. What I have found is a link to this Flight article.

    Scooter has, as he has often done before, made claims which are not supported by his source.
    Maybe he is just tired of doing everyone's research. According to Bill Sweetman:

    In the interests of fairness and objectivity it should be pointed out that it tends to be a smidge cold in January over the Baltic, which reduces the speed of sound. (Britain's Lightning fighter hit the Mach 2 mark in a late-November cold snap in 1958.) And one can assume that the jet was in clean configuration.
    http://www.aviationweek.com/aw/blogs...7-e5df04b98bd2

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    Quote Originally Posted by nhampton View Post
    I meant to say it can super
    cruise at all altitudes.
    That is something I would like to see any evidence/pilot statement
    or anything. SC at sea level surely must be a very difficult thing to do, especially for a jet that was not designed to fly anything near sea level.

    Most jets in full AB can only go a few 0.1's of a mach past 1 at sea level, nevermind cruise. The only jets that I can think of that could do anything like a slight cruise is the F-111F and the Tornado, both have had IAS at sea level in excess of M1.3, the ADV version slightly higher. But even they would do the majority of the flight high subsonic, not supersonic, and certainly not a supersonic cruise and those jets were designed to fly ~ 100ft, not 60,000+ft as in the F-22'S case.

    If it can I will be impressed. (not just in favourable conditions like many other fighters have experienced)

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    Quote Originally Posted by typhoon1 View Post
    That is something I would like to see any evidence/pilot statement
    or anything. SC at sea level surely must be a very difficult thing to do, especially for a jet that was not designed to fly anything near sea level.

    Most jets in full AB can only go a few 0.1's of a mach past 1 at sea level, nevermind cruise. The only jets that I can think of that could do anything like a slight cruise is the F-111F and the Tornado, both have had IAS at sea level in excess of M1.3, the ADV version slightly higher. But even they would do the majority of the flight high subsonic, not supersonic, and certainly not a supersonic cruise and those jets were designed to fly ~ 100ft, not 60,000+ft as in the F-22'S case.

    If it can I will be impressed. (not just in favourable conditions like many other fighters have experienced)

    The F-14 Tomcat was also "very" fast on the deck.............Which, is why it was to bad the it wasn't converted into a Attack Aircraft instead of the Eagle.
    F-35 Lightning II

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    Quote Originally Posted by nhampton View Post
    Whats the matter flex you don;t like facts do you? Take for instance your statement on the SH. Yes it has excellent maneuverability especially at low speeds. Given that it has "excellent electronics" and HOBS then it also is an excellent WVR performer as well. Not only that Flex my friend, the radar it is currently flying with is better than any non American radar in service today.
    No.. No one here said that SH is an WVR excellent performer, only you and I certainly don't agree with it. Radar is irrelevant in WVR, HOBS is a standard to others, as well. Maneuvrability at low speeds is good, but you bleed energy in one-two turns. Agility is poor. Result - average WVR performer. Certainly not an excellent one.

    Quote Originally Posted by nhampton View Post
    Hmm I read somewhere that the guy who gets in the first shot probably gets the first kill. This is something that consistently misunderstood by fan boys and trolls like you.
    I won't accept names rom someone who is a troll himself. Sorry, try something better.

    Quote Originally Posted by nhampton View Post
    It really doe not matter if Super is a bit sluggish in some situations. Given it's electronics and weapons it will consistently detect, track and engage it's adversary before it's adversary can return the favor. It won't matter if it's a thrust vectoring SU-30 with an RCS the size of a barn door, a Eurofrauder with all it's "carefree handling" and DASS or JAS 39NG with it's second hand collection of avionics from a variety of countries parts bin.
    Again, no... Either speed matters or it does not. If SH's sluggishness does not matter, then Raptor's supercruise does not, as well. Or vice versa. You cannot have everything, although you try to twist it so that you do.

    Quote Originally Posted by nhampton View Post
    Nice try AL but I know for a fact my penis is the longest in the world. The fact is some on this forum can make claims without needing a source but others if the claims are not what most want to hear in this venue cannot. Sorry, I am not buying. I cannot reveal sources sometimes.
    I don't believe that you have any credible sources in the first place. If you expect that we will treat your words like Bible because *you have sources, only cannot reveal them*, then you are terribly mistaken.

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    accelerated to Mach 1.2 and cut the afterburner

    About supercruise I once asks a rafale pilot (last fall in Paris) in which extent it could supercruise and his answer was quite consistent with the gripen NG statement. He said that only the F22 could break the mach barrier and sustain supersonic speed without AB. other aircarfts like the rafale or the typhoon had to engage the AB to break the barrier of sound and then only they were able to sustain supersonic speed witout reheat.

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    There's also a matter of fuel efficiency...

    You'd better use the AB for a few seconds than using the max dry power for a much longer time... ?
    Rafale news blog by Kovy :
    http://rafalenews.blogspot.com/

    The Rafale international forum :
    http://rafale.freeforums.org/

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    Quote Originally Posted by nhampton View Post
    Assume 1/2 hour of fuel remains with the throttle set to military power.
    Ah now here I think is the problem. Does the Raptor have half an hour fuel for supercruise?

    Although travelling supersonically without reheat uses less fuel than travelling supersonically with reheat it uses more fuel than travelling below the transonic hump without reheat.

    I have never seen any figures which suggest that raptor can maintain supercruise for 30 minutes. If anyone has any link to such I'd love to read them.



    Al

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    Quote Originally Posted by TMor View Post
    There's also a matter of fuel efficiency...

    You'd better use the AB for a few seconds than using the max dry power for a much longer time... ?
    Exactly. That's why Concorde used reheat. It could accelerate through the transonic hump without reheat (proved in tests), but because of the time it took, it was more fuel-efficient to use reheat briefly.

    That's one of the reasons I call the insistence that any use of reheat means "it isn't supercruise" akin to a religious dogma. The proponents of the idea are obsessed with the purity of their idea. They are not interested in practical realities, but only the One True Word of the Great God Lockheed Martin.

    I wonder what they imagine the afterburners on the F-22 are for.
    Last edited by swerve; 13th May 2009 at 21:46.
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    Quote Originally Posted by swerve View Post
    I wonder what they imagine the afterburners on the F-22 are for.
    You fool, that's the last ditch Anti-AAM defence.................




    Al

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    Like I said Only the F 22 (may be EF as well) does the real Super Cruise. The rest is all marketing gimmick using the AB to go over Mach 1 etc.
    Last edited by ante_climax; 13th May 2009 at 23:17.

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    Quote Originally Posted by swerve
    A valuable ability, but if the MiG-31 can fly even further supersonically while afterburning, one can see there's more than one way to skin a cat. There's a confusion between ends & means in many minds. Something is done to achieve a particular aim, & they cannot see that if the aim is achieved by different means, it has still been achieved.

    The F-22, Concorde, etc. supercruise(d) in dry thrust. Same end as SR-70 & MiG-31, different means. And how you get there is irrelevant: what matters is that you get there with enough fuel to maintain the speed for a significant, useful, distance.

    Let's be practical, not dogmatic.
    Concur, if the MiG uses AB is irrelevant as long as it can maintain supersonic flight, i had a comparison in some thread here.

    Here it is:

    MiG-31:Combat radius: 720 km at Mach 2.35 (450 mi) (389 nm)

    F-22: Combat Radius (NM)
    Mission 1 (Sub+Super) 260+100nm 310+100nm at ~Mach 0.85 sub + Mach 1.7 dash
    or an average speed ~half that of MiG-31* *my comment

    http://wapedia.mobi/en/MiG-31

    http://www.f22-raptor.com/technology/data.html
    Last edited by obligatory; 14th May 2009 at 03:22.
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    Quote Originally Posted by Al. View Post
    Ah now here I think is the problem. Does the Raptor have half an hour fuel for supercruise?

    Although travelling supersonically without reheat uses less fuel than travelling supersonically with reheat it uses more fuel than travelling below the transonic hump without reheat.

    I have never seen any figures which suggest that raptor can maintain supercruise for 30 minutes. If anyone has any link to such I'd love to read them.
    Al
    It can supercruise for 30 minutes or close to it but don't get fixated on it. I used 30 minutes in the example so that the math would be easy to follow. Just dive MPH in half to get distance traveled.

    As for 30 minute supercruise according to published figures the Raptor has a combat radius on internal fuel of 410 nautical (not statute) miles. One hundred nautical miles each way is in supercruise and the other 310 is at something less than M1.0. One nautical mile is equal to 1.15077945 statute miles. Converting the radius to statute miles give the following: 472 miles total combat radius, 357 miles radius below M1.0 and 115 miles radius at supercruise. Double those numbers since its given in radius and you get the following for total distance traveled:944, 714, and 230. All on internal fuel. Given those numbers using supercruise the Raptor consumes a bit over three times as much fuel in supercruise as it does below M1.0 so if you used external tanks to take off and reach your patrol area and then jettison them so you have full internal fuel when you start to supercruise you would be able to do so for about 500 miles or close to 1/2 hour at M1.72 and 40K.
    Link to the source for the basic range numbers:
    http://www.f22-raptor.com/technology/data.html

    Quote Originally Posted by MP703
    I believe the F-22 can SC at mach 1.9 at all altitudes! Need a source? Why?
    I cannot give you a source for M1.9 because it was given to me unofficially and has not been published. I explained my "all altitudes" grammatical mistake earlier. I can tell you that if you look in a magazine called Air Forces monthly a man named Mark Ayton wrote in the August 2008 issue an article titled "Raptors Roar In" and in it he says the F-22 supercruises at M1.82. Pretty damn close to M1.9 and it's published.

    Quote Originally Posted by Swerve
    Exactly. That's why Concorde used reheat. It could accelerate through the transonic hump without reheat (proved in tests), but because of the time it took, it was more fuel-efficient to use reheat briefly.

    That's one of the reasons I call the insistence that any use of reheat means "it isn't supercruise" akin to a religious dogma. The proponents of the idea are obsessed with the purity of their idea. They are not interested in practical realities, but only the One True Word of the Great God Lockheed Martin.

    I wonder what they imagine the afterburners on the F-22 are for.
    Concorde was not a military jet. What Concorde did for the sake of economy may or may not have bearing depending on the situation on what a military jet would do.

    One very good reason for the Raptor to not use AB when going supersonic is for signature management. Why light up the sky with infra red when you don't have to. The afterburners are there for when it makes tactical sense to use them. I would think it is a distinct advantage to have the option of using them when every other tactical jet must use them.

  30. #120
    Join Date
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    I would to remind everyone that is was just this last Feb that some "official" F-22 performance statistics were revealed. Which included supercruise @ Mach 1.78. Although unofficial comments by a number of pilots who have flow the F-22 indicate it to be higher than that. My 'guess' is that the Mach 1.78 refers specifically to 'extended sustained cruise under specific/standard conditions @ specific/standard operating altitude & throttle setting' while the pilot comments refer to what they have done outside such specific conditions...

    I would also like to point out that LM/USAF/US DOD coined the now popular term "supercruise" & they defined it as cruising >Mach 1.5 without the use of afterburner. When they talk about supercruise, they mean >Mach 1.5...

    As to how long/far the F-22 can "supercruise"...just keep in mind what ever you see/read/hear that it can cruise longer/farther @ say M1.5 than it can @ >Mach 1.75. And if you want to play the 'redefining supercruise to >Mach 1.0' game it can cruise @ say Mach 1.25 for even longer/farther.

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