F-22 vs. Rafale dogfight

Anything goes, as long as it is about the Lockheed Martin F-22 Raptor
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eloise

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Unread post03 Aug 2017, 07:17

degrasse wrote: when you see a vortex it can often mean that they loosed their efficiency

Wow, so invisible vortex that can't be seen have the highest efficiency ?


degrasse wrote: reason why they use pressure measurments and not little pictures or Youtube videos to figure them out

So what pressure measurement between Rafale Eurofighter, F-35 and F-22 that you have posted? and i mean CFD of all 4 not just a single one of them and you try to extend it with your fanboy nonsense

degrasse wrote:Sure thing, that of F-18 were the cause of much trouble, excessive drag and aerodynamic bashing of the vertical fins, they departed (stalled) from the aiframe boundary layer at high AoA and that's NOT a sign of efficiency, quiet the opposite. READ Dryden conclusion on the subject, the fix were the two dorsal strakes added later, another topic you missed.

Nice try, but no. The same thing that caused F-18 vertical fins to crack also gives F-18 better control authority at high AoA than Rafale or F-16. The vertical fin crack because vortex hit it with very strong force but if the vortex doesn't hit the vertical fin at AoA, then you will not have the same level of yaw authority


degrasse wrote:On the F-22, the strake vortexes barealy interact with that of the LEX, they are not vertically separated from the main wing plan chord, so their efficiency is limited when it comes to interacting with the wing vortexes, their primary role is Yaw stability, NOT increased roll control auythority
Then it is pretty obvious that the F-22 strakes do not prevent wing tip airflow stall at high AoA simply because there are NOT vortexes there to help.

In your own photo, the vortex still help decrease pressure at the ailerons when it start to burst. So it does help with roll authority. More importantly, what is the speed and AoA of the F-22 in the photo? where is the Rafale, Eurofighter contour in same situation?
I can find contour of F-35 with much wider affected area with its LERX vortex, and the wing tip has low pressure as well.


degrasse wrote:that's the job of adequately positions canard tip vortexes

Yet , you gave no contour of Rafale in the same situation to show the advantages? :drool:



degrasse wrote:If "Vortexes strength" and how they look in pictures is all you know about it

and vortex strength play a vital role. Like it or not, stronger vortex, more notifiable vortex mean lower pressure, that means higher lift.

degrasse wrote: no wonder you keep getting it wrong on all topics

Said the guy who talks so much nonsense on all aviation forum and so well known for his stupidity that he don't dare to admit who he is. :wink: Yes Picard you are not fooling anyone


degrasse wrote:At least i know what i am talking about

No you don't, you just know to throw a bunch of terminologies together, pushing some of your opinions and petend it is fact, too bad but this is not Indiandefense so your fanboy opinion doesn't flew well here. Either you give exact number and their respective CFD contour or GTFO

degrasse wrote: me not being an expert makes you what exactly? :mrgreen:

It makes me a smart guy that doesn't buy into your BS and don't talk so much nonsense that he became a running joke in all aviation forum :wink:



degrasse wrote:Yes but only on a limited part of the wing, as demonstrated by the Dryden studies on F-18/22 and F-35, AND the only relevant picture here, that of F-22 pressure tests at high AoA that proves it.

So where is the study ? where is the contour of Rafale at the same AoA and speed where its vortex cover the whole wing ?
Btw, how about this cotour of F-35 ?
Image



degrasse wrote:Yes it CAN, not only i saw it do so at Franborough at the hands of Yve Kerherve and timed it, but i also had the pleasure to read some leaked report on early flight testing, not your literature since everything remotely complex seems to elude you, let me explain; 100* AoA and negative speed, control flight during mock combat vs Mirage 2000 down to 18 kt (by memory). In fact ALL good design should be able to rotate on the YAW axis using ailerons at extreme high AoA in departed flight, if you flew anything else than a surf in your bathroom you'd know it.

:lol: How typical of you Picard
First made an outrageous claim then when people demanded evidence, you start with " oh i talked to that pilot", " i read super secret report". If you indeed see it at an airshow then there must be loads of videos of that airshow, all over youtube, go find it and the video of X-31 turning with TVC, then we timed it. How about that ? Or you cann't find the video of either since they demonstrate super extreme secret capability of Rafale?



degrasse wrote:Then, you not being aware or not knowing about things doesn't make them impossible, it just make you waste forum space, being unaware and lacking basic knowledge.

:slap: So now iam unaware because iam not buying your BS ? nice try but not gonna work here mate. It is ironic how you talk a lot with so little sources and number and try to push your agenda in as if they are fact.


degrasse wrote:Yes it does, being FCS limited to 100 kt and <> 32* for operational reaons doesn't mean it is its aerodynamics envelop limits, you obviously do not comprehend the difference between the two.

:doh: and you think they just randomly limit Rafale operational AoA to 32*, nope, its because unlike aircraft with twin tails or TVC, Rafale cannot take advantages of post stall maneuver.Sarcasm on Isn't it such a coincident that all single vertical stab aircraft are limited to such low AoA in operational even though they can reach higher value in testing.
Hmm I wonder why :roll:

Sarcasm off

degrasse wrote:And how so?

How so?
*Sarcasm on Hey look F-16 with fuel tank reaching 90* in test and recover :mrgreen: OMFG *Sarcasm off

:doh: if that was Rafale, i bet you would think it has a supreme high AoA fighting capabilities
Last edited by eloise on 03 Aug 2017, 12:23, edited 3 times in total.
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Unread post03 Aug 2017, 07:19

degrasse wrote:SAY WHO?

Anyone who understand physics

degrasse wrote:The guy who got it wrong from A up to now?

Don't be so harsh on yourself, atleast you get the plane name correct


degrasse wrote:A thigh AoA your control in the YAW axis will depend on much more than the number of fins you have

Tell me again, how does the Rafale have more fins than F-35 or F-18 :wink: me think you mixed it up with Su-30

degrasse wrote:It will mostly rely on the quality of the airflow over the fuselage, hence the importance of vortex position relative to those surfaces.

Yet you haven't give a single contour of Rafale

degrasse wrote:It appears that bar looking at photos, you do not comprehend what vortexes are in the first place

speak for yourself


degrasse wrote: for your info they are pressure zones, and seing them is not necessarily the sign of their efficiency, often the opposite as they become more visible AFTER departure.

Number Picard, we need actual number and source, not your BS babbling

degrasse wrote: To obtain a higher degree of yaw control at high AoA, IAI and the Swiss used small strakes on the nose, at the pitot tube root, you dont see the resulting vortexes but they certainly work just fine, all they need to do is generate the right amount of energy at the right place.
Image

and you know the vortex of F-35 and F-22 not at right place how ? do you have a similar chart for them with and without vortex? no you don't , Do you have the vortex contour of Rafale ? no you dont.
and LERX will also help to generate vortex so your point about vortex lift is moot.


degrasse wrote:
In short, the typcal delta wing vortex lift appears ealier in the AoA scale

still less efficient than low swept wing with LERX

degrasse wrote: you got lower drag for the same AoA

Where in your graph that it shows you can have lower drag for the same AoA with strakes and canard?

degrasse wrote: more ailerons authority AND the strakes increases YAW control and stability.

And how would you know F-22, F-35 LERX doesn't help with Yaw authority? where is the contour of Rafale at high AoA ?


degrasse wrote: Only they are NOT causing the same issues than on the US A-C since the pressure zones are properly situated and there is no departure from boundary layer or aerodynamic bashing because those vortex have departed.

More babbling BS, no side by side contour but you concluded that pressure zone of delta are properly situated, how the heck do you know if there are departure from boundary layer or not ?


degrasse wrote:
On F-35 they lost the benefit of the vortex expension
due to a very basic design fault, since they did not foresee the interaction between the strakes vortexes and the zone of lower pressure behind the cockpit, the vortexes does NOT expend outward and does NOT energise that of the wing,

Opps CFD say otherwise, contour at AoA of 10*
Image
Image
Is this expanding enough ?
Image
Or do you prefer this ?
Image

degrasse wrote:
What a genius. I'll let you rewrite the book for beginers, and demonstrate how little you know your subject.
Image
So F-35 vortexes helps do they? So far, they only were caused of a similar structural issue to that of F-18 and F-22 before it, certainly not helping lower drag or increasing lift or Yaw control authority, in fact, they did not what they were supposed to do at all.

Oh, so there is vortex on F-35 but they don't help increase lift? So the low-pressure area just magically disappears and not have any interaction with the airframe at all, and the vortex hitting the vertical tail but magically not affect yaw authority :doh: What a complete moron


degrasse wrote:
What a bag of bulls, especially when talking about low speed and/or post stall capabilities. Do your home worke befopre posting.

Funny how, despite your talk about having right amount of vortex at the right place, Rafale never demonstrate anything close to a pedal turn that F-35, F-22 , PAK-FA, Su-35 all done? and it is limited to 32* AoA in combat what a coincident :roll:

degrasse wrote: Certainly not, "move the nose around from side to side" at high AoA is not the the same thing,

watch the whole video, how do you think the put it in a spin and recover ?


degrasse wrote:
To ignorants everything sounds like nonsense, especially reality

As expected of fanboy, a lot of talk without source, without number and getting angry when others not buying their BS. Such a coincident that you can't give any numbers or video to prove your point. I wonder why :roll:




degrasse wrote: No it is not, quiet the opposite, you do not need a twin tail you need good airflow around the aiframe, and none of those A-Cs are optimised comparatively.

Yet nothing to demonstrate the super magical awesome airflow of Rafale compared to Su-35, PAK-FA , F-22 , F-35



degrasse wrote:You don't need a video, all you need is a proper aerodynamic knowledge and comprehension of what does what, this way you'll be able to figure and sort out forum legends like those you propagate and reality, best example is comparing post stall control of F-35 with that of a close-coupled canard.

So there isn't any video of Rafale performing post stall maneuver such as the pedal turn
In operational it's AoA is limited to 32*
Rafale doesn't have twin tail to catch the vortex from LERX
Rafale doesn't have TVC to provide torque at very low airspeed
yet our friend Picard here keep insisting that Rafale has better post stall capabilities with his theories of optimum airflow :doh:


degrasse wrote: And it's NOT lift which is going to make a difference at high altitude but thrust

:roll: all aircraft pull less than their maximum G limit at high altitude but according to you lift isn't going to make a different :roll:


degrasse wrote:in BOTH case, Rafale have a higher lift/drag ration than those, another moot point.

*Sarcasm on Wow you must have possessed the Cl, Cd curve of all 3 aircraft to speak with such high confident, please do share with us :drool: *Sarcasm off.


degrasse wrote:Speak for yourself, i just remind you that maximum turn rates INCLUDES maximum g loads in the equation

yes, but higher maximum structure G does not equal higher maximum turn rate. Nvm that you have nothing to show the ultimate structure G limit of either Typhoon or F-22

degrasse wrote: plus you need to twist my words since i didn't use the word "always" but instead specified a particular part of its flight envelop.

alright, you said
in any case it will out-turn both F-22 and Typhoon in instantaneous and sustained turn rates from low speed to subsonic.

i believe that you must possess EM charts of all 3 aircraft to say with such confident? . Opps let me guess, it is theory again and you have no number? or the charts are super extremely secret that you cannot share with anyone ?


degrasse wrote:
So within it, Air Density and payload allowing, by virtue of a higher Lift coefiscient, lower wing load, lower drag resulting from its canard-delta formula, what do you expect?

Not so quick mate, where are the lift coefficient-AoA charts of Typhoon , F-22 and Rafale?
Where are the Drag coefficient - AoA chart for Typhoon , F-22 and Rafale?
where is the stability vs speed chart for F-22?
Or do your fan boy brain automatically assume close coupled canard+ delta is better?

degrasse wrote:
For sustain turn rates, just add thrust vs drag and you have pretty much the same results until the performances of the engines makes the difference, that means Rafale would eat a Typhoon alive below 35.00 ft on the basis of lift/drag ratio, and comfortably live with F-22 at up to a lower altitude for this very reason.

Yet another confident fanboy assessment with zero number

degrasse wrote: it was a drag race, it won and its pilot is certainly not THE specialist of drag management a F-22 pilot is supposed to be.

what drag race? what speed and what was the time?

degrasse wrote:What we know for sure is what i wrote

Yes, we do know most of what you wrote are BS, that why your name became so infamous in the first place

degrasse wrote: Rafale aerodynamic optmisation allows for a higher lift/drag ratio, and its boundary layer and vortex control is way more developed, we know how and why, we also know why it is not the case for the A-C you compared it with = end of debate.

:mrgreen: yep, no charts or number comparison but you so sure that Rafale is better and more developed. That based on what ? your fanboy opinion?

degrasse wrote:While you're showing photos and posting little videos you forget the most important thing here, energy management, in real life, this fanboyz favourite airshow stunts doesn't work, and more to the point they are the reasons why both SAAB and Dassault aviation did NOT relax the operational limitation of their airframe to reach the aerodynamic limits.

It is a loop not a high post stall maneuver so your point is moot.
In real life, nothing beat a good HOBS missiles

degrasse wrote:You really do not comprehend the simplest thing about high AoA do you? Again, you do NOT need a twin fin, you need good roll and YAW control which are both reliants on airflow, and fuselage boundary layer control, which is better than that of the A-C you quoted in the case of Rafale. We just demonstrated that the US aircrafts were not top on this topic

Yep, behold the supreme optimum airflow of Rafale aerodynamic where you don't even need the air to hit the control surface for it to works
What more? it allows the Rafale to have extremely strong torque at stall speed even stronger than TVC breaking aerodynamic laws


degrasse wrote:Dryden studies as evidences but eh, i doubt very much that reality is your friend on this one, better forum legends and aerodynamics for beginers.

Funny how you keep reapet Dryden study yet doesn't understand why the stab has crack
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Unread post03 Aug 2017, 11:43

Wrong, differential deflection of the canards. The problem with that is in a canard-single vertical stab configuration there are three issues:
Vortex coming off the deflected canards interact with the vertical stab.(edit- on one side, which is an issue.)
The yaw rate is insufficient to control directional instability as AoA increases
The use of the canards to control yaw limits pitch rate- ironically the very thing you were bragging was superior on the Rafale.

No Picard I'm not visiting your blog to drive up revenue. I think the previous posters suggestion of YouTube should be your target audience.


Talk about entertainment and Youtube culture...

Then... You base your "conclusion" on that of a decoupled canard configuration, namely the X-31, while neither Rafale nor Gripen uses differential deflection because it induces tortional structural stress they do not want to compensate for with extra weight.
Plus they do not need it, since the formula provide with the necessary levels of control in all axis, did you read ANY of Dryden studies on the subject of this A-C?
I think not.

If you had known the difference between coupled and decoupled or anything about X-31, Gripen and Rafale for that matter, you wouldn't have posted this in the first place. I frankly prefer to post "i do not have any figure on that specific obviously" than the B.S you just wrote.

Differential deflection was used on the X-31 to create yawing moments in a view of getting rid of the fin for stealth purpose, but in departed flight, ANY good design can achieve this by using simple ailerons deflection, you simply need to be at an AoA where all airflow departed from the upper surface of the wing, in a flat spin, and obviously flying a sound aerodynamic design if you don't use TVC.

Point: The long moment arm canard is notorious for not having the good low speed/departure resistant and recovery characteristics of the close-coupled configuration, in particular, it CAN enter a superstall due to the longitudinal separation of its surfaces, just like a conventional design, and lacks the control authority to get out of it.

Saab demonstration yaw rate was about 90*/sec, the French always were more discreet about the results of their test having given (leaked) only max AoA and controled flight minimum speed achieved during testing. And oh i was wrong, it was not 18 kt minimum controled flight during a mock combat vs a 2000 but 15 kt. Source; Rafale flight test manager himself.

http://rafalefan.e-monsite.com/medias/f ... en-vol.pdf

The real interesting bit is what you missed about boundary layer control (among other things) while your pal brought up the subject of fuselage lift, so let me give you the scoop:

1) At this sort of AoA, > from 45 to 100*, ANY vortex coming from the canard tips will depart away from the rest of the airframe, the fin of X-31 is totally immersed in its wings wake at 50* aoA, so ANY extra level of control of the fuselage boundary layer is welcome. Here is a Dryden demonstrative photo of this:
Image

2) So here comes the little matter of fuselage boundary layer control features: At which AoA does your fuselage boudary layer depart? What are the design features allowing to keep it steadily energised at higher AoA? Did you notice that i mentioned airflow compression and extension and where on the aiframe could this apply to Rafale design? How would this help controling the fuselage's boundary layer and energise its Canards root vortexes + fin? I know the answers to that but i am 100% positive you do not.

You concluded that i was wrong (while i did NOT reply) and managed to mix up every single points here, good going...

Picard is more of a system guy and was not about when i first started uploading such stuff and later digged this video, as you havent figured it yet, i know the story behind this ATLC encounter from those who participated and got the video from an active member of the French Armed forces.

Under a "for your eyes only" agreement, i emailed it to Craig Hoyle, Flight Global military Editor at the time, WAY before it went public, to demonstrate the extend of the B.S posted by some self-proclamed specialist/journalist, i dont need a forum gurus to tell me results he invented, i knew them before he even posted his fairytales.

Here is a real AdlA 1/7 Squadron culture thing, when i said EQUAL: Out of 6 encounter, each side managed ONE kill, the rest were 0 scores within the allocated time for the fights.
Image

My field are aerodynamics and researche, and i always make sure i checked what i post and can prove it with proper sources as i just did several time over, forum legends does reality no good and are easily debunked, so i equally can easily see how you managed to get your wires so badly crossed and are unable to comprehend how a Rafale can beat a F-22 in a drag race.

Which brings us back to the topic's subject, how? Simple, more lift, less drag, low speed, now study the provided doc, it's not here for bashing but educational purposes...

Are NASA/Dryden documentation on the A-C (you do not know and) keep writing about not good enough? There are TONS more on those subject out there, F-16, F-18, F-22, F-35, ALL: X- aicraft programs, how did you manage to miss THIS?


About the X-31; they tested this mainly from 40 to 70* AoA which is the maximum they never reached, same figure for the E-F btw, both with a long moment arm, decoupled canard configuration offering a set of totally different and more AoA restricted aerodynamic capabilities.

Gripen post-stall maneuvers were achieved from 70 to 80* AoA, its max being 90*, 10* lower than the disclosed maximum reached by Rafale, and we have little detail so far of what those tests results really were but here is a clue about Gripen, originally from a Swedish website Mach Flyg.
http://www.mach-flyg.com/utg80/80jas_uc.html.

Quoting U. Claréus, project manager, JAS 39 Aerodynamics, Saab Aerospace.

"In the high AOA and spin tests that has taken place since 1996 and recently concluded successfully, the normal tactic was to initiate the tests with a near vertical climb with speed dropping off to near zero and a rapid increase of AOA up to extreme angles, and the aircraft could then be “parked” at 70 to 80 degrees of alpha.

When giving adverse aileron input there, a flat spin with up to a maximum of 90 degrees per second of yaw rotation started and could then be stopped by pro aileron input. Recovery followed, whenever commanded".

That's post-stall maneuver for you and 90*/sec yaw rotation is FASTER than what X-31 reached with TVC, as for Rafale we know that ONERA simulated J and HERBST turns before high AoA flight testing with exploring their combat usefulness in mind.

The Gripen document also mentions the clear advantages enjoyed by the close-coupled configuration over the long moment arm.
http://raf-fly.blogspot.co.uk/p/aerodyn ... ourth.html

When it comes to X-31 here is a little Dryden document you missed too which further proves these points.
Image


This is why on the issue of pitch rate (LOL!) in this flight regime you managed to make me laugh A LOT, as if Rafale's canard surfaces sole purpose were to be used in pitch anyway (on top of the "diferencial" thing)...


They're not only used as pitch attitude or control surface, they also actively participate to the Lift/Drag ratio management, and delta wing response to close coupled canard change of incidence is way better than conventional or long moment arm designs.

This goes for the ailerons and elevons alike. Gripen and Rafale do not have this X-31 issue of slugish/marginal pitch control authority at all, Rafale configuration was developed and optmised with 3 prototypes, namely Mirage 4000, IIING and Rafale A.

Now, as i do not have any figure on that specific obviously, i can only speculate based on KNOWN AND DOCUMENTED FACTS on what does what at which AoA passed the FCS 32* AoA limit:

So here goes: Close coupled canards are MORE efficients than long arm/decoupled ones or conventional designs at every levels, not mentioning fuselage boundary layer control features coupled with canard root vortexes on Rafale, changed for strakes on Gripen for lac of vertical space on the fuselage, which also explains its canards DIHEDRAL.

So the point on the AoA scale where ailerons MUST be used to compensate for the lack of rudder authority on Rafale MUST be higher than that of X-31 which fin is totally immersed in the wings wake at 50* AoA and doesn't posseses such feature.

This was demonstrated by the maximum AoA reached by both those A-C during testing. Period and simple logic, learn your stuff.
Image

Of interrest are the conclusions of Dr. Wolfgang Herbst, designer of the X-31 and TFK-30 aka Eurofighter Typhoon:
Image
Image

Savvy?

Obviously, you guys needs to spend much less time on Youtube and/or antagonising people in forums, freaking out about this Picard guy every time someone post any positive stuf on Rafale, and a lot more studying your subjects in a more down-to-hearth, scientific way with proper sourced documentation, you dont know your basics, you dont know your aircrafts, your lot.
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Unread post03 Aug 2017, 14:31

eloise wrote:
degrasse wrote:SAY WHO?

Anyone who understand physics

degrasse wrote:The guy who got it wrong from A up to now?

Don't be so harsh on yourself, atleast you get the plane name correct


degrasse wrote:A thigh AoA your control in the YAW axis will depend on much more than the number of fins you have

Tell me again, how does the Rafale have more fins than F-35 or F-18 :wink: me think you mixed it up with Su-30

degrasse wrote:It will mostly rely on the quality of the airflow over the fuselage, hence the importance of vortex position relative to those surfaces.

Yet you haven't give a single contour of Rafale

degrasse wrote:It appears that bar looking at photos, you do not comprehend what vortexes are in the first place

speak for yourself


degrasse wrote: for your info they are pressure zones, and seing them is not necessarily the sign of their efficiency, often the opposite as they become more visible AFTER departure.

Number Picard, we need actual number and source, not your BS babbling

degrasse wrote: To obtain a higher degree of yaw control at high AoA, IAI and the Swiss used small strakes on the nose, at the pitot tube root, you dont see the resulting vortexes but they certainly work just fine, all they need to do is generate the right amount of energy at the right place.
Image

and you know the vortex of F-35 and F-22 not at right place how ? do you have a similar chart for them with and without vortex? no you don't , Do you have the vortex contour of Rafale ? no you dont.
and LERX will also help to generate vortex so your point about vortex lift is moot.


degrasse wrote:
In short, the typcal delta wing vortex lift appears ealier in the AoA scale

still less efficient than low swept wing with LERX

degrasse wrote: you got lower drag for the same AoA

Where in your graph that it shows you can have lower drag for the same AoA with strakes and canard?

degrasse wrote: more ailerons authority AND the strakes increases YAW control and stability.

And how would you know F-22, F-35 LERX doesn't help with Yaw authority? where is the contour of Rafale at high AoA ?


degrasse wrote: Only they are NOT causing the same issues than on the US A-C since the pressure zones are properly situated and there is no departure from boundary layer or aerodynamic bashing because those vortex have departed.

More babbling BS, no side by side contour but you concluded that pressure zone of delta are properly situated, how the heck do you know if there are departure from boundary layer or not ?


degrasse wrote:
On F-35 they lost the benefit of the vortex expension
due to a very basic design fault, since they did not foresee the interaction between the strakes vortexes and the zone of lower pressure behind the cockpit, the vortexes does NOT expend outward and does NOT energise that of the wing,

Opps CFD say otherwise, contour at AoA of 10*
Image
Image
Is this expanding enough ?
Image
Or do you prefer this ?
Image

degrasse wrote:
What a genius. I'll let you rewrite the book for beginers, and demonstrate how little you know your subject.
Image
So F-35 vortexes helps do they? So far, they only were caused of a similar structural issue to that of F-18 and F-22 before it, certainly not helping lower drag or increasing lift or Yaw control authority, in fact, they did not what they were supposed to do at all.

Oh, so there is vortex on F-35 but they don't help increase lift? So the low-pressure area just magically disappears and not have any interaction with the airframe at all, and the vortex hitting the vertical tail but magically not affect yaw authority :doh: What a complete moron


degrasse wrote:
What a bag of bulls, especially when talking about low speed and/or post stall capabilities. Do your home worke befopre posting.

Funny how, despite your talk about having right amount of vortex at the right place, Rafale never demonstrate anything close to a pedal turn that F-35, F-22 , PAK-FA, Su-35 all done? and it is limited to 32* AoA in combat what a coincident :roll:

degrasse wrote: Certainly not, "move the nose around from side to side" at high AoA is not the the same thing,

watch the whole video, how do you think the put it in a spin and recover ?


degrasse wrote:
To ignorants everything sounds like nonsense, especially reality

As expected of fanboy, a lot of talk without source, without number and getting angry when others not buying their BS. Such a coincident that you can't give any numbers or video to prove your point. I wonder why :roll:




degrasse wrote: No it is not, quiet the opposite, you do not need a twin tail you need good airflow around the aiframe, and none of those A-Cs are optimised comparatively.

Yet nothing to demonstrate the super magical awesome airflow of Rafale compared to Su-35, PAK-FA , F-22 , F-35



degrasse wrote:You don't need a video, all you need is a proper aerodynamic knowledge and comprehension of what does what, this way you'll be able to figure and sort out forum legends like those you propagate and reality, best example is comparing post stall control of F-35 with that of a close-coupled canard.

So there isn't any video of Rafale performing post stall maneuver such as the pedal turn
In operational it's AoA is limited to 32*
Rafale doesn't have twin tail to catch the vortex from LERX
Rafale doesn't have TVC to provide torque at very low airspeed
yet our friend Picard here keep insisting that Rafale has better post stall capabilities with his theories of optimum airflow :doh:


degrasse wrote: And it's NOT lift which is going to make a difference at high altitude but thrust

:roll: all aircraft pull less than their maximum G limit at high altitude but according to you lift isn't going to make a different :roll:


degrasse wrote:in BOTH case, Rafale have a higher lift/drag ration than those, another moot point.

*Sarcasm on Wow you must have possessed the Cl, Cd curve of all 3 aircraft to speak with such high confident, please do share with us :drool: *Sarcasm off.


degrasse wrote:Speak for yourself, i just remind you that maximum turn rates INCLUDES maximum g loads in the equation

yes, but higher maximum structure G does not equal higher maximum turn rate. Nvm that you have nothing to show the ultimate structure G limit of either Typhoon or F-22

degrasse wrote: plus you need to twist my words since i didn't use the word "always" but instead specified a particular part of its flight envelop.

alright, you said
in any case it will out-turn both F-22 and Typhoon in instantaneous and sustained turn rates from low speed to subsonic.

i believe that you must possess EM charts of all 3 aircraft to say with such confident? . Opps let me guess, it is theory again and you have no number? or the charts are super extremely secret that you cannot share with anyone ?


degrasse wrote:
So within it, Air Density and payload allowing, by virtue of a higher Lift coefiscient, lower wing load, lower drag resulting from its canard-delta formula, what do you expect?

Not so quick mate, where are the lift coefficient-AoA charts of Typhoon , F-22 and Rafale?
Where are the Drag coefficient - AoA chart for Typhoon , F-22 and Rafale?
where is the stability vs speed chart for F-22?
Or do your fan boy brain automatically assume close coupled canard+ delta is better?

degrasse wrote:
For sustain turn rates, just add thrust vs drag and you have pretty much the same results until the performances of the engines makes the difference, that means Rafale would eat a Typhoon alive below 35.00 ft on the basis of lift/drag ratio, and comfortably live with F-22 at up to a lower altitude for this very reason.

Yet another confident fanboy assessment with zero number

degrasse wrote: it was a drag race, it won and its pilot is certainly not THE specialist of drag management a F-22 pilot is supposed to be.

what drag race? what speed and what was the time?

degrasse wrote:What we know for sure is what i wrote

Yes, we do know most of what you wrote are BS, that why your name became so infamous in the first place

degrasse wrote: Rafale aerodynamic optmisation allows for a higher lift/drag ratio, and its boundary layer and vortex control is way more developed, we know how and why, we also know why it is not the case for the A-C you compared it with = end of debate.

:mrgreen: yep, no charts or number comparison but you so sure that Rafale is better and more developed. That based on what ? your fanboy opinion?

degrasse wrote:While you're showing photos and posting little videos you forget the most important thing here, energy management, in real life, this fanboyz favourite airshow stunts doesn't work, and more to the point they are the reasons why both SAAB and Dassault aviation did NOT relax the operational limitation of their airframe to reach the aerodynamic limits.

It is a loop not a high post stall maneuver so your point is moot.
In real life, nothing beat a good HOBS missiles

degrasse wrote:You really do not comprehend the simplest thing about high AoA do you? Again, you do NOT need a twin fin, you need good roll and YAW control which are both reliants on airflow, and fuselage boundary layer control, which is better than that of the A-C you quoted in the case of Rafale. We just demonstrated that the US aircrafts were not top on this topic

Yep, behold the supreme optimum airflow of Rafale aerodynamic where you don't even need the air to hit the control surface for it to works
What more? it allows the Rafale to have extremely strong torque at stall speed even stronger than TVC breaking aerodynamic laws


degrasse wrote:Dryden studies as evidences but eh, i doubt very much that reality is your friend on this one, better forum legends and aerodynamics for beginers.

Funny how you keep reapet Dryden study yet doesn't understand why the stab has crack
Video vortex Rafale:
https://youtu.be/l_WQH0zObEE?t=1s
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f-16adf

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Unread post03 Aug 2017, 17:33

I like the Rafale alot, but they seriously need to give that jet improved engines.




It finally does a full 360 degree turn at 4:17.

https://www.youtube.com/watch?v=l_WQH0z ... tu.be&t=1s


Granted Gloucester was 20 C (68F) on July 15th and 24C (75F) on Sunday so density altitude probably was not all that high.


That's a nice turn, but I have seen stock SU-27's and small tail F-16A's, let alone GE powered Vipers, turn quicker than that.



Rafale has an impressive ITR, but STR needs improving....
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Unread post03 Aug 2017, 23:39

You dont seem to understand, i asked for a source, if you actually have the source then post the link here :wink: let me guess : the source is some super secret document that only you have access to ? or did it came from some "expert" on forum ? how convenient :slap:


You're quiet LOUD mouthed for someone who doesn't know how turn rates are computed...

LOL! The pathetic troll feast, you guys kiss your mums with mouth like these?

My source were the French AdlA on French MoD website, and the 1/7 pilots in charge at the time, plus 1/7 is still today a multirole Squadron, years after this ATLC which took place when the Squadron was implementing weapon, systems and tactics for the A2G role at first, no need for a "source" to know this, you write and write and blah-di-blah but know little about it all.

Sorry mate but this is not Indiadefence where almost everyone are retarded and just believes every single word you say without demanding evidence.


Oh, is see, ultra-p"""d because India didn't fall for your "superior" A-C and chosed instead to buy Rafale are we? Nope, i did not post in this forum for years, seek councelling to take care of those acute paranoia and sore bum, and you could also do something about your superiority complexion because many of the Indian posters there are WAY more educated than you, perhaps one reason they dont need som much miking and takes no sh"t from you...

So that mean all pilots from 1/7 are of equal skill ? and there are no amateur F-22 pilot ?what a joke


This mean exatly what i wrote, at the time NONE of the 1/7 pilots came from Air Superiority Squadrons but transformed from Jaguar or Mirage 2000D which as everyone know but you are Strikers, NOT air superiority fighters, you know what? Trolls always asko for sources and links, enthusiats find them.

As for the 27 FS, certainly NO "amateurs" there, but pure A2A specialists with Air Superiority as sole mission all the way from 1942, flew F-86, F-89, F-94, F-102, F-106, F-4, were the FIRST to fly F-15 in 1976, not much pound for air to ground here, you're sh*t out of luck.

They transformed to F-22 mid-January 2006, while the 1/7 were transforming from Jaguars to Rafale a few mont later, before deploying to Af'stan, having been on hold without their Jaguars for an entire year, not much Air superiority there either. and certainly not hard to figure which Squadron was the most trained in A2A.


Nice try, but as usual you are so full of sh*t


Again this photo was taken on arrival at the exercise, anyone aware would know but you (meamning those who actually were there), it doesn't take much time to paint this on an A-C side, and you keep taking your case for a world standard, not everyone is that clueless.

If this F-4 killed a Rafale, it might well have been in BVR when the Squadron Rafales didn't have what it takes to take them on at long range, true, at this stage of their evoution, they were more often used as plastron in BVR but this have changed with AESA radar, SECTRA and now Meteor upgrades.

They even go as far as writing Frisian flag 2008 and Rafale eater on it LOL. The truth must be so hard for a fanboy like you to swallow, and no there wasn't any Eurofighter in Frisian flag 2008


And NO definitively the silouete is NOT that of a Rafale, there are enough distinctive features on it to figure this one out as well so this let much questions unanswered, like how can anyone confuse this for a Rafale or consider for one second that GAF F-4 never crossed GAF Typhoon in actual exercises at home even during this exercise, or that it is just the silouet of the A-C they were about to transform to?... And you keep caling people fanboyz?

How do you know if F-22 pilot also want to roll ? or do you think the counter to one maneuver is to do exactly the same ? :doh:


That's exactly what he did during the whole engagement but you can't figure what is what on a video, talk about fanboyism, you dont even comprehend what vertical yo-yos are, not loops there, so it implies rolls at the top, so both A-C DID roll, you even can see the F-22 doing just that.

Oh really? mind giving me the exact name of their airfoil ?


Rafale's airfoil is clasified as is that of every Dassault fighter since a good while, that of F-22 is a supercritical designed by Dryden, i believe developed under the NASA SCW technology program. How come you dont know this already?

you are the one without any clues here but of course you don't want me to post any picture because it will just destroy your argument


You mean you delude yourself into thinking you are doing it while posting w.h.a.t.e.v.e.r together with completely false assumptions and ignoring reality, sure...

None of the picture you post actually made your false points, aerodynamicist such as those i quoted does make the point for me, so does the Dryden doc about F-18 vortex "efficiency", as opposed to your funny interpretation of basic aerodynamics, your bunch clearly dont know what you're writing about and prefer reality denial to actual technical debate...


You group the characteristics of the main wing with vortex generating devices?


Absolutely, since they work the exact same way as LEX only on a larger scare and are wider.

As i said, delta wings generates their own main vortexes at their root with or without LEX/canard, that's precisely the characteristics of delta plans, vortex lift and it's NOT only happening at high AoA, especially with close coupled canards and/or moderately swept deltas like F-22 or Rafale, not even on Mirage IIIs which is something you totaly failed to notice after the results graphs of the IIIS flight test were posted to you.

You like pretty pictures it seems.
Image

Here special MTO conditions i keep mentioning, allows the wing root vortex to be visible, which they wouldn't without the amount of moisture in the air, they are those which are nearest to their departure point as well (low speed, + AoA) although a long way from it. Now, the most important are those you do NOT see, canard root and tip vortexes, and those of the LEX. If that's not clear enough for you, like the rest of it, it's due to some deficiency from your side...

The other wing vortexes take root on the UNDERWING leading edge and need to go around it, they also are weaker than the main root vortex.

Question: Knowing nothing about it, having such a low sense of obervation, why do you keep spaming the forumn pages with ignorant B.S instead of learning your basics?

so you don't even understand why they put LERX on F-16, F-18 in the first place
follow your logic all aircraft should have delta wing and LERX and Canard since more vortex creating devices = better.


Sorry, YOU meant to say that YOU dont understand what LEX are or does, or what vortex lift is, that's a clear fact by now, and they are NOT called LERX but LEX as named by their inventors, ask Dryden/NASA, they knows tons more than you do.

Nope, delta wing can generate vortex at high AoA, that what give them higher max AoA than a normal straight or low swept wing.Because the vortex stops flow separation.


What a bag of bulls, so according to you genius, Rafale rotates at high AoA during take off? :bang:

You can't even read a Mirage IIIS graph with lift and Aoa given to you, such Delta wings vortex are the sole source of their lift as early as they take a moderate AoA, using canards only trigger the appearence of vortex lift at even lower AoA, therefore reduced induced drag.
Image
Here pressure computation, shows clearly the difference between the main vortex and the others, on a highly swept delta, the LEX/wing root have exactly the same characteristics and will generate a main vortex the exact same way.

Now; conclusion of the Mirage IIIS tests: "The canard produces two additional vortices which combine with the vortices on the delta wing.

This gives an extension of controlled airflow up to a higher AoA and an unshielded fin and rudder.

The vortex lift starts earlier, which results in reduced drag at a given lift
(see Fig 1).At a given AoA, the canard configuration gives more lift and less drag than the canardless delta configuration.

The improved yaw stability permits higher AoA, and therefore lift and drag are
approximately doubled with the canards
".
https://www.flightglobal.com/pdfarchive ... 03298.html

And THIS is with a old 58* swept Mirage III, not a 48* + LEX canard like that of Rafale note that there is no question of "can generate vortex at high AoA" but up to higher AoA, and vortex lift starting earlier, not your disneylandish version of reality graph plus report = you proven completly our of your league. Again.

So what were you saying about F-16/18 sweep angles and LEX? Close coupled canards achieve the SAME, add LEX to them and you get MORE lift than simple LEX/wing configuration regardless of sweep angle, with added benefits such as more natural damping (no transonic bump or limitation such as those seen on F-16 or E-F), more tolerance to out of CG range or assymetric loading, LOWER drag in all flight regime, better trim drag.

What does "an extension of controlled airflow up to a higher AoA and an unshielded fin and rudder" and "improved yaw stability permits higher AoA" to you? A great need for a second fin?

If you look at the graph, it shows the appearence of vortex lift way before reaching a third of its Max AoA, which is moderate since it is only a Mirage III with 58* swept delta, vortex lift will appear much earlier on both F-22 and Rafale, even without the canards.

But that does not mean delta can generate higher total lift/unit area than a straight or low swept wing at similar AoA, its lift curve is far less steep.


Well it's bound to do just that by sheer mechanical logic, since delta plans are simply larger in surface for equal weight, offer more internal volume for fuel, drag less in transonic and supersonic while being larger, offering a lower wing load, one of the reasons why it was chosen for the F-22 in the first place and neither F-16 nor F-18 have straight wings as opposed by what you keep writing but swept wings.

As for F-18 it is notoriously dragy because of its LEX size and generates more drag by simple virtue of insteady vortex, so revise your copy on turn rates and control authority because Dryden who tested this A-C flight envelop disagree with your bunch of bulls, there is a long way between beginers theories and reality.

Higher the sweep angle, the less steep the lift curve would be.


Again you completely missed the points here as usual, their sweep angle is moderate for a delta at 48*, both Rafale and F-22 doesn't have the sort of issue both F-16 and F-18 have, (bar the vortex breakdown in the ailerons area in the case of F-22), they combine BOTH the characteristics of the delta and straighter wings by just being moderate in swep, use LEX, and being larger in surface than if they used swept wings, plus canards on Rafale.

The delta plan offers MORE surface for LOWER structural weight, equals more lift for lower drag, so your theory falls flat on this basis only.

Now if one take into account the drag generated by F-18 LEX while Rafale is optimised for a much higher lift/drag ratio, you can pull whatever stunt you like and post all the web litle pictures, you wont make your points.

Many aircraft have LERX, yet retain their low swept wing because that help them combine the benefit of both delta and low swept
Delta = higher AoA
Low swept = higher lift at the same AoA


Actually no, it doesn't works quiet just like that in real life either, it's a tad more complext than your little pictures and fantasist interpretations would let us believe for the many good reasons i already demonstrated: Quote someone who knows his subject, as opposed to you:

"The close coupled delta canard configuration’s primary feature, its stable vortex flow up to very high angles of attack, meaning high maximum lift coefficient, had lately been realized by the Americans, instead using large strakes as forward wing root extensions together with conventional tail arrangement, as found on the F-16 and F-17/18".

So according to the designer of Gripen, which can eat any F-16/18 for breakfast in WVR, the reason WHY US designers used LEX on both the A-C you mentioned is to obtain stable vortex flow up to very high angles of attack, which is THE particularity of a close coupled delta canard, is that what you call the aerodynamic bashing encoutered on F-18 or vorteexes breakdwon on F-22 wings? It proves that you have absolutely NO idea whatstodever how vortexes works.
U. Claréus, project manager, JAS 39 Aerodynamics, Saab Aerospace.

So where are the actual numbers to back up this point? or is this another a$$ pull of your?


You had the answer from a master aerodynamicist, so i think a$$ pulls are what you make of reality when it's way too complex for you... We're FAR from your complete lack of understanding and knowledge of aerodynamics and aviation history aren't we?

And something else, BOTH F-16 and F-18 have more than one aerodynamic gremlin, as demonstrated by Dryden studies (those your bunch wont read for cause of nervous diarrhea).

F-18 have aerodynamic bashing inducing drag, yep, it drags way more than any of those other A-C, F-16 is well known for its AoA limitations (risks of superstall) AND not being tolerent to assymetric load in the transonic regime where it would DEPART when the pilot pulls a small amount of G with only one AAM attached to its wingtip rails, so much for aerodynamic excellency.

THIS is completely unknown to the Delta canards, they are a lot more tolerant to assymetric load due to natural damping, yet another little detail you know nothing about, you like your little Youtube newbies feeders? Enjoy:

https://youtu.be/Rv9YC-gaNYo

btw, the only reason i post this video AFTER your pal is that i couldn't post up to now, but i understood what this topic was about while he totally mised the point, LOSS of control flight in the transonic regime is not equivalent to post-stal maneuvers capabilities, it is a flaw, not a quality and the test pilot says it clearly, in an area where the A-C is prone to depart.

Close-coupled canard does NOT depart, not in assymetric loads either, and have little of the transonic issues known by conventional configuration A-Cs.

As for confirmation from Gripen designer on the subject of how easy it is to obtain the same results from a conventional design, here, a little picture for you.
Image

said the troll who pull everything out of his a$$ without any sources or number


So obsessed with this part of your anathomy, it looks like the center of your intelligence, no wonder you seems to be totally unable to comprehend your basics, they're lost somehere in a place far remote from your mind...

All talk but not a single source or actual number for comparison between Rafale and F-22 and Btw, wing tail configuration with negative stability will have their horizontal tail add up to the total lift, something canard cannot achieve


Considering what you do of the sources one can pass on to you it's like feeding a goldfish with four stars Russian caviar hoping for it to get smart enough to get a Nobel Price in quantum mechanics, every single serious source on the subject conterdict you, enuff said.

Your funny theories falls short when one looks closely to what is actually happening with the A-C you keep comparing Gripen and Rafale to, they simply are not on par aerodynamically with F-22 and even less Gripen or Rafale.

So where are the actual numbers to back up this point? or is this another a$$ pull of your?


What? A pressure zone simulation of F-22 vortex breakout and departure from Dryden an a$$ pull?? Yeah, i know your buddy managed (or so he like to think) to turn vortex breakdown, a defisciency, into aerodynamic excellence, but i beging to understand why you guys are so deluded.

It's all good if you forget induced drag, lower lift and control surface authority due to unsteady vortexes and the rest of it and consider vortex brakedown as efficient as stable vortex flow, which goes some way to demonstrate how little you guys have comprehended the subject in the first place...

Sums you up doesn't it, posting a F-16 departure due to lack of control and damping in the transonic regime and come up as proof of possible recovery (I'd be worried if it havent been able to recover) from high AoA post stall maneuver takes some doing, same for the F-18 and F-35 aerodynamic bashing, that's a proof of good airflow is it, uncontroled departed spins and controled flight be it post-stall are thew same?

I think you dont even know the meaning of the words flight and control at all.

Sorry but i'll skip the rest of your paranoiac, flame bating troll feast wee-wee contest after this post, i do not do t**s feeding, you guys need to get nannies or psys or both, learn your very basics and accept reality for what it is, which is going to take time, and then some, considering how far in your fantasy world you're all gone.

So it's just yet another Dryden educated document you havent managed to read or get your head around, as usual, being vulgar, agressive and taking on "what's his name? Picard" with personal attacks doesn't make your point but make you look like a complete freaked out ignorant with no argument at all.
Get the PDF and learn your basics, then perhasps if you comprehended what it says we can talk aerodynamics, in a few years, if ever.
http://www.dtic.mil/dtic/tr/fulltext/u2/a245152.pdf
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Unread post04 Aug 2017, 10:26

On the subject of high AoA maneuver
Benefits of TVC and high angle of attack:
Image

Twin tails or single tail:
Image
Image

Effects of LEF:
Image
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Unread post04 Aug 2017, 12:40

garrya wrote:On the subject of high AoA maneuver

Twin tails or single tail:



I see we go to the same book shop.

Very interresting study here, note that the need for stealth and vertical surfaces tail reduction dictated the choice for twin tails configuration, but it still need to use all its surfaces + TVC to obtain those levels of lateral stability and pitch/roll control.

Most of Dryden links for test flight results are dead now, including that of YF-22 but i can recall their recommandation for the cranked trailing edge for cause of vortex breakdwon causing excessive bashing in this area, they also recommanded a reduction of the wingsweep to the actual 48*.
Image

Funny Rafale and F-22 ended up with similar leading edge/LEX configuration...

And before some paranoiac trolls start jumping up and down screaming "Picard" , this image is the result of my own studies and photoshop work, and it's been a while... (what was i saying)... :bang:
Image

As i said, one is designed for stealth and as such have to compromise with shapes and configuration, the other conceived with hyper-maneuvrability in mind from day one with no compromise but aerodynamic optimisation, the main difference between them being the canard surfaces and mostly the effects they have on ALL axis, providing with stable vortex flow up to very high angles of attack.

Vortex breakdwon are not part of what stable vortex flow up to very high angles of attack defines, aerodynamic bashing is not as efficient as stable aiflow, regardless of vortex strength, cleaner airflow works way better.

On the effects of close-coupled canards:
"The close coupled delta canard configuration’s primary feature, its stable vortex flow up to very high angles of attack, meaning high maximum lift coefficient, had lately been realized by the Americans, instead using large strakes as forward wing root extensions together with conventional tail arrangement, as found on the F-16 and F-17/18".
U. Claréus, project manager, JAS 39 Aerodynamics, Saab Aerospace.

So according to the designer of Gripen, the reason WHY US designers used LEX on both mentioned A-C is to obtain stable vortex flow up to very high angles of attack, which is THE particularity of a close coupled delta canard and visibly NOT the case of the A-C experiencing vortex breakdown or aerodynamic bashing phenomenons at any point.


What you do NOT see... Airshows are nice, Youtube videos are nice, but there is little there for proper analysis, better get the information where it is than jumping to false conclusions...
Image

Here special MTO conditions allows the wing root vortex to be visible, which they wouldn't in this case without the amount of moisture in the air, they are those which are nearest to their departure point as well (low speed, + AoA) although a long way from it. Now, the most important are those you do NOT see, canard root and tip vortexes, and those of the LEX

The A-C AoA at rotation is lower than 15*, it is a stable 16* on appropach and the configuration for the FCS active lift/drag optimisation is obviously different, biased for low speed, descent slope angle and rapid deceleration.

Now; conclusion of the Mirage IIIS tests:

"The canard produces two additional vortices which combine with the vortices on the delta wing.

This gives an extension of controlled airflow up to a higher AoA and an unshielded fin and rudder.

The vortex lift starts earlier, which results in reduced drag at a given lift (see Fig 1).At a given AoA, the canard configuration gives more lift and less drag than the canardless delta configuration.

The improved yaw stability permits higher AoA, and therefore lift and drag are
approximately doubled with the canards
".
https://www.flightglobal.com/pdfarchive ... 03298.html

This is why a sound close-coupled canard-delta design does NOT need a twin tail, it will retain a proper level of yaw control up to AoA where the fin will be completely immersed in the fuselage wake and ailerons will have to take over in this axis anyway.

On X-31, it's 50* AoA, but on Gripen and Rafale (which does not use differencial canard deflection btw), it is higher, simply because their canard are aerodynamicaly coupled and that of X-31 are NOT.

Now, there are design features on Rafale meant to increase the fuselage boundary layer energy at up to higher AoA in a view to improve yaw control authority other than close-coupled canard root vortexes, clue; on Gripen they are strakes.

I am still holding the info to see if anyone can figure it out, since i'm restricted for posting i'll be back later with more fun, but dont expect me to respond to the trolling wee-wee contest of those frustrated by their "been owned by uncivilised Indians" experience. Some comments starts to sound pretty xenophobics and have no place in an aviation forum...

@ garrya ps: Good to see one can have a proper technical debate in here, but i cannot reply to your post below by restriction, i have to edit.

Yes those A-C are hardly comparible simply because they do not respond to the same set of requirements and i keep pointing this out, stealth means aerodynamic compromises, but when it comes to their performances in this topic's video, the fact that Rafale can roll at speed as low as 80kt (and he didn't push it, just done it right for the circumstances, there is NO FCS-built-in restriction for speed) is one of the reason why the Rafales were able to equal F-22 in this encounter.

Those graphs even without scales are interesting in that they give a good idea of the difference between the two configuration, they also includes the effects of the strakes mounted on the pitot tubes (similar in purpose to that of F-22 and Kfir), i'm sure you will find the whole article of most interest.

The parralel i make between F-22 and Rafale at this level is still perfectly valid when you compare their respective plan form, in particular LEX and leading edge angles, considering the purpose of the vortex sources and what they are doing for the airframe airflow as a whole.

The F-22 lacks the 4th set of vortex offered by the canard wingtips, which energises the outer wing boundary layer, thus offering a higher level of roll control at high AoA, a particular feature F-22 does not posses simply because its design point is stealth instead of hyper-maneuvrability.

The canard root vortexes does the same job as F-22's strakes and are not meant to extend futher outward than mid-wingspan, as a matter of fact, when not combined with canard tip vortex, they brake down, looses their efficiency and in the case of F-22 (F-18 before it and F-35 after it suffers the same problem for slightly different reasons) caused structural fatigue due to aerodynamic bashing.

On the other hand, they keep a steady airflow on the fuselage fin and rudder, which is much easier to achieve on a single fin for cause of aerodynamic bashing, on top of increasing lift by interacting with wing root (and LEX) vortexes.

So vortex root position matters a lot more than their "strength" (See F-35 wandering strake vortexes), vertical separation of forward vortexes is also a factor increasing the efficiency of their interaction with the outer wing vortexes, so it is one aspect where F-22 stealthier features works against its aerodynamic efficiency in comparison and one of the reason they breakdown instead of staying steady.

Then "strength" is a word with little meaning since there are only MAIN and RESIDUAL vortexes, only the main vortexes matters and once you have a root for them, their strength will be pretty much equivalent from an A-C to another for the same speed/AoA.

So all i am doing is to explain within this particular contest HOW a Rafale with no TVC and lower TWR is capable of equaling a F-22 in a WVR encounter (and not as some have perceived launching a wee-wee contest)...

In a drag race, Rafale is near unbetable at low speed, simply because its aerodynamics are optimised for this purpose, this goes up to speed and altitude where engine thrust will take more importance and it's a long way from 80kt or 9.0 g +.

What mattered in this particular topic, was its ability to roll at those speeds and recover its energy fast enough to outfly the F-22 in this drag race, despite F-22 higher TWR and use of TVC, that's Lift/Drag optimisation, aiflow control allowing for a higher level of energy management.

We can further debate on the benefits of the close-coupled canard formula in other area of the flight envelop when i am able to post, but there are tons of good documentation on the subject, including from NASA/Dryden, Hans Herbst, U. Claréus, Swiss MoD, and some leaked Dassault-Aviation flight testing program management.

I'm sure you can find most of it goggling them. Have a good day.

To others unaware French bashing specialists: A little reality strike, final score was 1/1 and 4 nils.

Here is a real AdlA 1/7 Squadron culture thing, when i said EQUAL: Out of 6 encounter, each side managed ONE kill, the rest were 0 scores within the allocated time for the fights, with love from the 1/7 pilots.
Image

1 sec fire at 2500 r/pm with a hit ratio of 90% gives you 46 rounds of OPIT 30mm on target, here is a F-22 in very bad shape (check the NEXTER 30mm characteristics for a laugh); reality denial does no good for good aviation forum debates.

As for the other AdlA Squadron, such as Air Superiority Mirage 2000 C/-5:
Image
Last edited by degrasse on 04 Aug 2017, 20:45, edited 10 times in total.
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garrya

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Unread post04 Aug 2017, 12:46

degrasse wrote:Very interresting study here, note that the need for stealth and vertical surfaces tail reduction dictated the choice for twin tails configuration, but it still need to use all its surfaces + TVC to obtain those levels of lateral stability and pitch/roll control.

IMHO, That is very vague definition, comparison is impossible without parallel data, especially considering that there is no scale on the graph either.

degrasse wrote:Image

As far as i understand it, these graphs shows the aerodynamic comparison between delta wing fighters with and without strakes, canard. It is not a comparison between delta wing with canard and trapezoid wing conventional lay out aircraft. Thus,while iam open to the possibility of Rafale more lift oriented than F-22, you are pretty much comparing Apples and Oranges when using those charts to compare F-22 and Rafale
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Unread post04 Aug 2017, 14:19

And before some paranoiac trolls start jumping up and sown screaming "Picard" , this image is the result of my own studies and photoshop work...


So you just created this picture right now ?

Seriously, anyone rational would say with 99%+ confidence you're Picard ; what are the odds of someone picking a picture posted by Picard, hidden so deep in the comments section on a page of the Aviationist you have to click on "Load more comments" multiple times, while not being Picard ?

And no, you're clearly not a professional, or even someone a little serious, if you don't bother to provide sources, and saying X is good at some point to only use the opposite argument a few paragraphs later.

Also, your picture is clearly the hallmark of a professional ; comparing the 18.92m long F-22A to the 15.27m long Rafale, with the same apparent size.
Everytime you don't tell the facts, you make Putin stronger.

Everytime you're hit by Dunning-Kruger, you make Putin stronger.
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mixelflick

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Unread post04 Aug 2017, 15:12

Jesus.

I just spent over an hour reading all this. Can someone tell me who "won"? :)
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wrightwing

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Unread post04 Aug 2017, 15:20

I love how he asks how it's possible that the Rafale outflew the Raptor, when it didn't win any of the engagements (while T-38s have managed to get simulated kills.) I think he defines outflew differently, than is traditionally understood. He's also one of the fans, that like to compare clean configurations.
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viper12

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Unread post04 Aug 2017, 15:51

mixelflick wrote:Jesus.

I just spent over an hour reading all this. Can someone tell me who "won"? :)


Ask yourself the following questions :

1) Who claims there were Eurofighters at Frisian Flag 2008, when there weren't (link 1, link 2, link 3) ?

2) Who claims X, Y, Z but doesn't bother to provide specific sources or links ?

3) Who posts a water tunnel test picture that's so well hidden deep inside the comment section of a specific The Aviationist article, a comment posted by Picard, a known fanboi whose "facts" have been debunked for years ?

4) Who claims to be a professional yet cannot make a picture at the same scale on both sides, or doesn't even know the standard symbol for degree, as in a 90-degree turn, as you've certainly noticed in his posts ?

After answering these questions, you know who "lost".

Or even better ; let [s]Picard[/s] degrasse use the equations shown here, the very ones he's quoted :

http://i146.photobucket.com/albums/r279 ... eqv9-1.jpg

Then see which numbers he gets after plugging in realistic numbers, showing every step of the computation ; chances are he won't get realistic ones, for reasons known to anyone with a minimum knowledge of science...
Last edited by viper12 on 04 Aug 2017, 19:19, edited 1 time in total.
Everytime you don't tell the facts, you make Putin stronger.

Everytime you're hit by Dunning-Kruger, you make Putin stronger.
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f-16adf

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Unread post04 Aug 2017, 17:57

It's great if the Rafale and Gripen flew to alphas above 80 or 90 degrees in tests. But with what we have seen (air show demos) ((and not by unverified internet diagrams)) their slow fight is not particularly impressive. Sure it's an improvement over the F-16. However, Flankers and Hornets can fly at higher alphas; and they have been doing it for years.

The F-14 Tomcat flew to very high alphas in testing, but that doesn't mean it was sanctioned for squadron service.


Show some actual E/M diagrams (not internet estimations) otherwise this is just becoming an exorbitant anecdotal fallacy.
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eloise

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Unread post04 Aug 2017, 18:23

f-16adf wrote:Show some actual E/M diagrams (not internet estimations) otherwise this is just becoming an exorbitant anecdotal fallacy.

It is not even an estimation of Rafale or F-22 aerodynamic,
He got the following:
_ Some graphs (without any number) about of benefits of canard for delta wing


_ A tunnel photo of F-35 shape in unknown condition
_ A contour of F-22 in unknown condition
( AoA and speed will change vortex and air flow formation , so each condition is entirely different in terms of lift and drag)
He has no contour or tunnel photos of Rafale in the same condition as F-22 and F-35 to compare, he just concluded that Rafale is better because "canard-delta", "more optimum vortex", "no stealth, super extremely optimum aerodynamic".

He has no Cl, Cd curve for any of the airplane in discussion, he has no dynamic thrust curve.Yet he concluded that Rafale will have best STR and ITR because again "canard super optimum" "11G structure limits"

He keeps insisting that Rafale has the best post stall fighting capabilities despite all evidence to the contrary because "close coupled canard"

and then he pretend to work in Military and start sharing his " stories", tried to lie about Frisian flag but get shut down immediately by me.
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