F-35 Lightning II vs Dassault Rafale

The F-35 compared with other modern jets.
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by end » 12 Sep 2007, 14:14

No one here think that F-35 will be too much overweight? think about its size just similar with Rafale but its weight over than Rafale almost 1 ton!
This will be the disaster for its engaged performance.
I think therefor I am


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by dwightlooi » 12 Sep 2007, 21:28

end wrote:No one here think that F-35 will be too much overweight? think about its size just similar with Rafale but its weight over than Rafale almost 1 ton!
This will be the disaster for its engaged performance.


Actually, the weight is ~3 tons more than the Rafale (~12.7 tons vs ~9.8 tons).

No, it will not be a disaster. The F-35 has 9000 lbs more thrust, it has sleeker aerodynamics when carrying a typical combat load (all internal), it has 3 tons more fuel to burn for speed if it needs to. It has much bigger control surfaces giving it superior control authority especially at high altitudes.

Let's put it this way... the F-35A is over a ton lighter than the F-18E, it has the same thrust for the most parts, it has much more fuel, and it flies clean with internal weapons. The F-18E has no problems whatsoever smashing Rafales so neither will the F-35A. In fact, it'll be a Turkey shoot.


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by Corsair1963 » 13 Sep 2007, 04:57

dwightlooi wrote:
end wrote:No one here think that F-35 will be too much overweight? think about its size just similar with Rafale but its weight over than Rafale almost 1 ton!
This will be the disaster for its engaged performance.


Actually, the weight is ~3 tons more than the Rafale (~12.7 tons vs ~9.8 tons).

No, it will not be a disaster. The F-35 has 9000 lbs more thrust, it has sleeker aerodynamics when carrying a typical combat load (all internal), it has 3 tons more fuel to burn for speed if it needs to. It has much bigger control surfaces giving it superior control authority especially at high altitudes.

Let's put it this way... the F-35A is over a ton lighter than the F-18E, it has the same thrust for the most parts, it has much more fuel, and it flies clean with internal weapons. The F-18E has no problems whatsoever smashing Rafales so neither will the F-35A. In fact, it'll be a Turkey shoot.


I just don't understand why it is soooo hard for people to get the F-22 and F-35 fly clean (i.e. internal weapons) during most missions. While, 4th or 4.5 generation types carry everything externally! Its not hard really............take a clean F/A-18 Hornet and fly it against a F-16 loaded with 2-PGM's, 2-External Tanks, 2 or 4 AAM's and a single jammer! Which, do you think will win in a purely WVR fight! That of course doesn't even touch the Stealth aspect of the 5th Generation Types nor Super Cruise in the case of the F-22.


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by SnakeHandler » 13 Sep 2007, 05:03

The US tried the delta wing idea back in the 70s and 80s. We learned, why hasn't Europe?


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by Scorpion82 » 13 Oct 2007, 00:59

SnakeHandler wrote:The US tried the delta wing idea back in the 70s and 80s. We learned, why hasn't Europe?


There is a huge difference between a conventional stable delta design and an aerodynamically unstable delta/all moveable canard design.


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by SnakeHandler » 13 Oct 2007, 01:03

They're still not as good.


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by Scorpion82 » 13 Oct 2007, 01:15

SnakeHandler wrote:They're still not as good.


Still not as good as what? Not as stealthy as the F-22 or F-35? Who wonders they weren't designed as allround covered stealth aircraft, they were designed with superior performance to the teen/teenski series in mind, next to other requirements.


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by Thumper3181 » 13 Oct 2007, 03:29

they were designed with superior performance to the teen/teenski


F-15s with the GE engines come to mind when it comes to raw performance and the Super Hornet when it comes everything else. Tiffie is a leap ahead when compared to Tornado. It just came 15 years too late.


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by dwightlooi » 13 Oct 2007, 05:25

Scorpion82 wrote:
SnakeHandler wrote:They're still not as good.


Still not as good as what? Not as stealthy as the F-22 or F-35? Who wonders they weren't designed as allround covered stealth aircraft, they were designed with superior performance to the teen/teenski series in mind, next to other requirements.


No, not as good in that the performance of delta-canards do not exceed that of the wing tail arrangements. The US tried unstable canards in platforms like the HiMAT and it has been modeled extensively in CFD studies. They just do not perform better in the aspects which matters.

The are many areas where delta-canards are inferior to wing-tails, there are only a few areas where they offer an improvement. Delta-canards suck because:-

(1) In general, achievable instability is not greater. Reason: the main wing is further aft, meaning that it is more inconvenient place the center of gravity of the aircraft aft of the center of lift. It is easier to do if the wing is forward.

(2) In general, high AoA control characteristics is not better. Reason: To create a pitch up force the canard has to be deflected up whereas the tail is is deflected down. In a high AoA situation, the canard experiences more flow separation and earlier stall vs a tail and stops being able to create a pitch up force at a lower AoA than a tail.

(3) Lift efficiency is typically worse. Reason: In an unstable design, the Cg is very close to or is behind the center of lift without a canard or tail's input. The main advantage of a canard in stable designs -- that both the wing and the canard provide lift -- is negate or reversed in unstable design. If the Cg is behind the combined center of lift of the aircraft the tail provides lift to keep the aircraft stable the canard has to provide downforce to keep the aircraft from back flipping.

(4) High AoA lift characterisitics is not better. Reason: In general deltas, with their high sweep and wide chord is, are poor wings. On top of that, LEX and forebody shaping is as good or better at creating lift enhancing vortices than canards.

(5) Stealth characteristics is worse. Reason: planform alignment of the leading and trailing edges, as well as the hiding of pivoting joints are harder to do on a canard-delta design.

(6) Low speed handling is inferior. Reason: The delta is a lousy wing compared to other geometry for producing lift at lower speeds.

(7) Ordnance carriage layout is inferior. Reason: Again, long chord, short span deltas make it hard to place weapon stations and pylongs under the wing -- just look at the EF or Mirages with a full load.

Delta canards rocks because:-

(1) Drag at very high speeds can be lower. Reason: With a high sweep and short span it is easier to tuck a delta wing within the shock cones created by the nose and other discontinuities. However, it has been shown that the sweep angles required for efficient Mach 2 speeds can easily be accommodated without a delta wing.

(2) High speed drag reduction can be had without horrendous handling compromises everywhere else in the flight spectrum. Reason: The canards allow for good control authority to mitigate some of the handling problems of a traditional Delta.

(3) There are less wing twist issues. Reason: The span span of the delta means the wing twists less under load and especially with outboard control surfaces acting to provide roll forces.


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by Scorpion82 » 13 Oct 2007, 13:24

Thumper3181 wrote:F-15s with the GE engines come to mind when it comes to raw performance and the Super Hornet when it comes everything else. Tiffie is a leap ahead when compared to Tornado. It just came 15 years too late.


All Typhoon pilots I spoke too and all interviews with Typhoon pilots I read/saw confirmed the Typhoon to be superior in flight performance to F-15, F-16, MiG-29 etc.. These pilots have a wide flying background and flew numerous types of aircraft including the teen series. According them you can already feel the difference and don't need to monitor the instruments and a stop watch to make out any difference as it was often the case when comparing teen series aircraft with each other. Comparing the Typhoon with the Tornado is basically a bad idea as they are totally different aircraft, designed for different missions.
Of course the Typhoon would have been better in comparison if it would have been there 15 years ago, but that applies to every new fighter.


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by Scorpion82 » 13 Oct 2007, 13:38

@dwightlooi
Both delta canards and wing/tailplanes have their pros and cons.
But you should take into account that different configurations are possible as well. The Rafale for example has a LEX like forward fuselage despite its delta canard layout. Typhoon has long coupled canards while all other fighters are close coupled canard designs. You have to see the entire aerodynamical layout as well. You claim inferior low speed and high AoA handling qualities, while the Rafale and Typhoon seem to speak against your arguments. Planform alignement can be achieved with delta canards as well, though this would have an impact on the aerodynamics and the wing/tailplane configuration is better suited for that. BTW aircraft like the Typhoon or Rafale has relative large deltas in comparison to earlier designs like the M2k etc..
BTW the ailerons don't move down in order to get the aircraft pitch up.


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by Thumper3181 » 13 Oct 2007, 17:47

All Typhoon pilots I spoke too and all interviews with Typhoon pilots I read/saw confirmed the Typhoon to be superior in flight performance to F-15, F-16, MiG-29 etc.


First off, what are they supposed to say. "My ride is second only to xyz, and if we come up against them we are screwed". Not going to be said, ever.

Second care to give an example of one who has flown a late model F-15?


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by johnwill » 13 Oct 2007, 21:11

The worst problem a delta has is the drag polar, a plot of coefficient of lift vs coefficient of drag. In other words, to get the same lift at higher AoA, the drag is higher than for a conventional wing. At low AoA (Concorde) they are fine. Typhoon gets around that with lots of thrust, at a cost of lots of fuel.

Not at all sure the delta is stiffer in twist in all cases. The wing tip area (aileron location) has a very narrow structural chord, so twist becomes a serious problem in high speed rolls.

Deltas also develop a strong nose-up moment at high mach. low altitude flight. This moment requires either elevon down for non-canard deltas or a down load on the canard for those with canards. Either way, more drag results, and the down load on the canard means the wing has to develop more lift to compensate.


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by dwightlooi » 13 Oct 2007, 23:44

Scorpion82 wrote:@dwightlooi
Both delta canards and wing/tailplanes have their pros and cons.
But you should take into account that different configurations are possible as well. The Rafale for example has a LEX like forward fuselage despite its delta canard layout. Typhoon has long coupled canards while all other fighters are close coupled canard designs. You have to see the entire aerodynamical layout as well. You claim inferior low speed and high AoA handling qualities, while the Rafale and Typhoon seem to speak against your arguments. Planform alignement can be achieved with delta canards as well, though this would have an impact on the aerodynamics and the wing/tailplane configuration is better suited for that. BTW aircraft like the Typhoon or Rafale has relative large deltas in comparison to earlier designs like the M2k etc..
BTW the ailerons don't move down in order to get the aircraft pitch up.


Oh, nobody is claiming that the Typhoon and the Rafale are not more maneuverable than say an F-16. The point is that those level or maneuverability can be achieved or exceeded with wing tail layouts as well.

Basically, the Canard-Delta is a configuration used to mitigate the worst short comings of a Delta wing. The configuration, in and of itself, does not promote better maneuverability, agility or efficiency over unstable wing-tail layouts.

And, yes, the canards pitch up to effect a strong pitch up moment on an delta-canard and the tails pitch down to do the same. If the design is sufficiently stern heavy, the aircraft will pitch up slowly with level canards or tails. However, in such instances the canard will have to provide downforce and the tails will have to provide lift to keep the aircraft level. Such is the case on the Typhoon under some loadings and such is also the case for the F-35 during cruise.


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by Scorpion82 » 14 Oct 2007, 13:15

Thumper3181 wrote:
All Typhoon pilots I spoke too and all interviews with Typhoon pilots I read/saw confirmed the Typhoon to be superior in flight performance to F-15, F-16, MiG-29 etc.


First off, what are they supposed to say. "My ride is second only to xyz, and if we come up against them we are screwed". Not going to be said, ever.

Second care to give an example of one who has flown a late model F-15?


And of course they would lie just to make their aircraft looking better :roll: I don't know why you discredit anything which might speak for the Typhoon, but according you we can't trust anything which is stated about this aircraft. Of course this just applies to the Typhoon and no other aircraft. :lol:


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