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Thread: USAF not F-35 thread

  1. #91
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    Quote Originally Posted by FBW View Post
    . They go: DI 0, 50, 150, 200 as a point of comparison.
    @Eagle, read the above again a starting point DI of 0 would be a clean airframe. Also, read the note at the bottom of first post. I'm well aware that you can add up the various drag numbers from the stores list. There are, however, no acceleration numbers for those. DI of 50 is a good starting point as you calculated yourself for an aircraft with centerline and wing pylons with 4 aams.

  2. #92
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    Quote Originally Posted by FBW View Post
    In terms of acceleration, the impact is not negligible:
    For an F-15E with the -229 engines, with a massive static T/W ratio at 45,000lbs of 1.296 here are the numbers clean and with 4 aam:

    10,000 feet clean mach .8 to mach 1.2: under 16 seconds
    10,000 feet with four aam: 17 seconds- not much difference

    40,000 feet clean: 40 seconds
    40,000 feet with 4 aam 45 seconds
    a 12.5% decrease in acceleration

    max speed difference is negligible for the F-15 because it is time limited but roughly .1 mach.

    For the F-16C which is much lighter fighter, at a gross weight of 24,000lbs ( which means it is low on fuel because the aircraft actually weighs 20,000lbs+ (not 19,000lbs as often quoted) with pilot and all lubricants and unusable fuel etc, it will touch mach 1.95 clean.
    With a DI of 50, reasonable if not low for 4 aam and pylons it's under mach 1.8

    The acceleration also takes a hit:
    at 10,000 feet 24,000lbs clean mach .8 to mach 1.23 takes 24 seconds
    at 10,000 feet 24,DI of 50 mach .8 to mach 1.23 takes 39 seconds

    clean at 40,000 feet mach .82 to mach 1.24 takes 61 seconds
    with a DI of 50 mach .82 to mach 1.24 takes 77 seconds

    Saying that 4 missiles and the associated pylons does not have an impact on acceleration is obviously wrong. Top speed is a little deceptive since both of the fighters are time limited on fuel so top speed is hypothetical anyway, the F-15E will not go above much above mach 2.3 clean or with missiles as it runs out of fuel (and the four aams are semi recessed so very little drag there). The F-16 looses about .15 mach with a DI of 50 ( the F-16 is also listed as a mach 2 fighter but the flight manual tops it out below mach 2, so I don't know)

    The point is: a smaller fighter is impacted by even the addition of pylons and missiles. The F-15E comes off better because the drag impacts it less, and frankly 4 semi-recessed missiles are not going to add a ton of drag (good news for the Typhoon).

    Edit- The DI 50 is the lowest listed, for a reason. Yes, the F-16 with two pylons+ missiles and two wingtip missiles can have a DI around 20, but how often does any air force remove all the other weapon pylons to clean the aircraft off? The DI of 50 about as low as they are going to fly with weapons.
    The point of the above seems to have been missed, carrying weapons and pylons has an impact. An impact that is greater on a smaller fighter.

    We can parse various DI configurations all day: two wingtip aam or two wingtip and aam on wings with pylons and adapters, or whatever. Even in the QRA pictures, the aircraft are carrying five pylons. Even when empty most will carry a min of centerline and four wing pylons. Most of the time the pylons stay on no?
    Last edited by FBW; 4th April 2015 at 17:07.

  3. #93
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    It seems we need to revisit these every month or so.

    If we took the same simplistic approach someone on this board did recently we would simply look at the stat sheet, see that the F-18C and Super Hornet's max speed is M1.8. They are therefor just as fast as each other. They are also both faster than the M1.6 F-35.

    Of course the reality is somewhat more complicated. With the same loadout the F-18C is marginally faster than the Super Hornet, and in a realistic air policing loadout with 4-6 AAM and at least one drop tank the F-35 will be significantly faster than either of them.

  4. #94
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    Quote Originally Posted by FBW View Post
    @Eagle, read the above again a starting point DI of 0 would be a clean airframe. Also, read the note at the bottom of first post. I'm well aware that you can add up the various drag numbers from the stores list. There are, however, no acceleration numbers for those. DI of 50 is a good starting point as you calculated yourself for an aircraft with centerline and wing pylons with 4 aams.
    Actually, a clean F-16C airframe has a drag index of 7
    I agree that DI 50 is a good starting point. Less than that is also possible, though unlikely in a real loadout. So at DI 50, top speed is Mach 1.85 vs 1.6 for the F-35. That, imho, is a valid comparison. Now, since the F-35 is not thrust/drag limited at Mach 1.6, it will still have some reserves at that speed. The question is: more than the F-16 at Mach 1.6? I think not, I bet an F-16C @ DI 50 will out accelerate an F-35 from lets say M 0.8 to M 1.6.
    It takes an F-16C-52 ~110 seconds @ 30.000 feet, the F-16C-50 needs ~85 seconds if I'm not mistaken. Unfortunately, we probably won't have solid F-35 numbers for some time.

    @ hopsalot: great, some data for the -402 engined Hornet. Do you have more?
    Last edited by eagle; 5th April 2015 at 15:39.
    How can less be more? It's impossible. More is more.
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  5. #95
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    Quote Originally Posted by eagle View Post
    Actually, a clean F-16C airframe has a drag index of 7
    I agree that DI 50 is a good starting point. Less than that is also possible, though unlikely in a real loadout. So at DI 50, top speed is Mach 1.85 vs 1.6 for the F-35. That, imho, is a valid comparison. Now, since the F-35 is not thrust/drag limited at Mach 1.6, it will still have some reserves at that speed. The question is: more than the F-16 at Mach 1.6? I think not, I bet an F-16C @ DI 50 will out accelerate an F-35 from lets say M 0.8 to M 1.6.
    It takes an F-16C-52 ~110 seconds @ 30.000 feet, the F-16C-50 needs ~85 seconds if I'm not mistaken. Unfortunately, we probably won't have solid F-35 numbers for some time.

    @ hopsalot: great, some data for the -402 engined Hornet. Do you have more?
    Most likely, I was responding to a misguided idea that external weapons have a negligible impact on performance. Not specific to any discussion about F-35.

    Trying to keep F-35 out of this thread as it evokes too many arguments, in too many threads.

  6. #96
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    Quote Originally Posted by eagle View Post
    Actually, a clean F-16C airframe has a drag index of 7
    I agree that DI 50 is a good starting point. Less than that is also possible, though unlikely in a real loadout. So at DI 50, top speed is Mach 1.85 vs 1.6 for the F-35. That, imho, is a valid comparison. Now, since the F-35 is not thrust/drag limited at Mach 1.6, it will still have some reserves at that speed. The question is: more than the F-16 at Mach 1.6? I think not, I bet an F-16C @ DI 50 will out accelerate an F-35 from lets say M 0.8 to M 1.6.
    It takes an F-16C-52 ~110 seconds @ 30.000 feet, the F-16C-50 needs ~85 seconds if I'm not mistaken. Unfortunately, we probably won't have solid F-35 numbers for some time.

    @ hopsalot: great, some data for the -402 engined Hornet. Do you have more?
    Sorry, I can't remember where the Hornet/Super Hornet chart came from and I don't have any more like it.

    I wish we had a more complete set for other fighters. Until then people will no doubt continue to make up whatever they want.

  7. #97
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    Quote Originally Posted by MSphere View Post
    Here a Hellenic Mirage 2000-5EG Mk2 and French Rafale C armed on QRA duty - 2x ARH MICA, 2x IR guided MICA, one drop tank (to be jettisoned).
    I have serious doubts the max speed or acceleration after climb is imparted by this loadout in any significant way.

    I think that this Rafale is actually carrying 6 AAMs, two Mica EM on the fuselage stations, two Mica IR on the wing tips & the two you can see on the pic on the wing pylons.

    Nic

  8. #98
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    http://breakingdefense.com/2015/04/t...strike-bomber/

    Have to say I'm rooting for NG. Don't think that investing all of the U.S. defense aerospace industries' aircraft design and production in Boeing/LM's mitts for the long term is in the best interest of the taxpayer.

  9. #99
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    Quote Originally Posted by Nicolas10 View Post
    I think that this Rafale is actually carrying 6 AAMs, two Mica EM on the fuselage stations, two Mica IR on the wing tips & the two you can see on the pic on the wing pylons.
    AFAIK, Rafales on QRA do not have missiles on fuselage stations.

  10. #100
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    Quote Originally Posted by FBW View Post
    Most likely, I was responding to a misguided idea that external weapons have a negligible impact on performance. Not specific to any discussion about F-35.
    as a matter of fact a drop from M2 to M1.85 is a negligible effect on performance,
    below 10% which is universally considered threshold between significant/insignificant
    ...and that was while carrying a drop-tank too

  11. #101
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    Quote Originally Posted by obligatory View Post
    as a matter of fact a drop from M2 to M1.85 is a negligible effect on performance,
    below 10% which is universally considered threshold between significant/insignificant
    ...and that was while carrying a drop-tank too
    Wrong again my befuddled friend. That's with ( 4 aam) + pylons no DT, and the speed drops from aroud Mach 1.95 to under Mach 1.8, and I explained why top speed is impacted less than acceleration which was impacted markedly.

    Taken right from flight manual, your assumption does not hold up to facts, drop it. External stores have a negative impact on performance, one that has been explained with real examples over and over by many different posters. If you fail to grasp this perhaps you should change your sign in name to " oblivious".

  12. #102
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    Last time I checked significant difference generally meant somewhere between 1.5% to 5% increments.
    Go Huskers!

  13. #103
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    tipping is a special case, where 10-15 cent or 1.5% can be considered a significant tip on a 10 dollar meal,
    here, a generous tip would simply transform into a blatant and quite rude show-off going up to a 10% one dollar tip
    Last edited by obligatory; 7th April 2015 at 05:39.

  14. #104
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    For the interested, the USAF FY '16 Budget breakdown is available at the airforce financial management site:

    http://www.saffm.hq.af.mil/budget/

    Interesting tidbit, an AMRAAM D costs 978,000 for FY '16 and goes down from there.

  15. #105
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    Quote Originally Posted by bring_it_on View Post
    So thats essentially what he is saying as well. The F-15C/D is going to be secondary to the F-22 and F-35 fleets, which would ultimately play a secondary role to the fighters that will look to replace them well into the future. No one is going to claim that the F-15C even with AESA and newer EW gear is going to be a cutting edge fighter in the 2030's nor will it act as such since its operator would have a sizable next generation fleet by then. As per the current plans the F-35 acquisition winds down in 2038 and by then the F-X should be in LRIP if not full rate of production. Depending upon how development, and budgets pan out you would be looking to either replace the F-15C/D's with the F-X (replace F-22+F-15C fleets) or continue buying more F-35's if there are cost or technical challenges developing or producing the F-X.

    UCAV's would obviously be in addition to this.

    @FBW, I suggest you change the title of the thread
    Spuddy, like many US orientated folk, assumes the Typhoon, Rafale and Gripen are equivalent to the F-15.
    He also assumes that only US tactics and methods are relevant.
    Anybody with a little more knowledge than just the US and US types knows those assumptions are inaccurate.
    Thus to claim that because the F-15 will become less effective the Typhoon etc. will also do so to the same degree is also inaccurate.
    Nic has done a good job of setting out how UCAV's will complement the current European fighters in the future.
    Last edited by snafu352; 8th April 2015 at 16:23.
    The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts.
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  16. #106
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    http://www.airforcetimes.com/story/m...reat/25418367/

    Reading between the lines, it comes off as a scare tactic to get congress to pony up money for the cancelled AESA upgrades to the F-16.

  17. #107
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    LRS-B gets funding cut for this year:

    http://www.dodbuzz.com/2015/04/27/ho...tealth-bomber/

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  19. #109
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    Eleven years after aim-9X entered in USAF service and three years after the last F-22 was delivered...

  20. #110
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    And at least five years before the F-22 gets any real competition.

  21. #111
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    As of now weapons upgrades are tied to block upgrades. This is true for most programs in the US. UAI is an effort to change that as you can field multiple weapons even in between updates thanks to the streamlined effort. It has already been rolled out in the F-15E and F-16 fleets and should be available to the F-35 fleet in the early 2020's. Aim-120D integration on the F-22A should also occur fairly soon and they plan on having an HMS as well around the end of the decade. Slow progress yes, but as mentioned above by Rii, it really has marginal impact on what rolls its likely to play in the next few years. It can be argued that giving it a SAR capability (which it does) is much more relevant to the immediate future.
    Last edited by bring_it_on; 13th May 2015 at 17:53.
    Old radar types never die; they just phased array

  22. #112
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  23. #113
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    Any signs ie pics or videos of F-15E models with AIM-9X?
    How can less be more? It's impossible. More is more.
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  24. #114
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    Yeah they carry them..Here's the SG carrying

    Old radar types never die; they just phased array

  25. #115
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    Saw this elsewhere on the web and thought it deserved a mention particularly given the heated debate about low level penetration and RCS over on the Rafale thread:

    http://defense-update.com/20150506_s...l#.VVRuIPlViko

    New AESA radar for the B1B with details of its ability to map and operate at different angles depending on which way the aircraft is facing in relation to the ground and those hunting it.

    Click image for larger version. 

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  26. #116
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    Has the USAF ordered this radar for the B-1B? How long will they continue to operate the B-1B?

    Edit: just looked further into the article:

    The development of SABR-GS took place under a $21 million risk reduction contract awarded in 2011 by the Air Force B-1 Systems Program Office. Northrop Grumman has demonstrated in flight, the advanced B-1 AESA and advanced sensor and fusion processing, readying the radar for the engineering, manufacturing and development phase.

  27. #117
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    Quote Originally Posted by Levsha View Post
    Has the USAF ordered this radar for the B-1B? How long will they continue to operate the B-1B?

    Edit: just looked further into the article:
    They've not set an hard out of service date. They've said that it will serve "at least through the 2030's"

    Some of the upgrades are needed and well overdue. Some of the crews were still buying handheld GPS receivers well into the Afghanistan conflict.
    Some of the recent work:
    http://defensetech.org/2014/02/21/ai...b-1b-overhaul/
    http://www.airforce-technology.com/n...-fleet-4569025

  28. #118
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    Will the B1's AESA be bigger/more modules than its fighter counter parts?

    And just a thought.... Why not turn the B1 into a long range EW platform? Can you imagine the amount EW power
    it would bring. It would be able to carry many AGM-88 missiles and jamming pods.

  29. #119
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    Will the B1's AESA be bigger/more modules than its fighter counter parts?
    Yes, Its 3 times the size of the F-16 SABR.

    And just a thought.... Why not turn the B1 into a long range EW platform? Can you imagine the amount EW power
    it would bring. It would be able to carry many AGM-88 missiles and jamming pods.
    The Core component jammer looked at that.

    Old radar types never die; they just phased array

  30. #120
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    It's a shame they canceled it. B1 would be better suited in my opinion.

    But i guess they went with this?

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