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Posts Tagged ‘comparision’

Aircraft performance parameters quick look

Posted by Picard578 on April 15, 2015

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Fighter aircraft gun comparision

Posted by Picard578 on February 1, 2015

Introduction

Despite repeated proclamations about the “end of the dogfight”, gun has always remained an important part of fighter aircraft’s armament. There are several reasons. Having a gun provides a psychological security of having a fallback option if missiles are expended. Gun also has far lower minimum range than even most agile of modern dogfighting missiles (very short ranges reduce missile kill probability even if target is not within missile’s minimum range), and is the most versatile weapon aircraft has – it can be used in dogfight (shooting down aircraft), in air policing (warning shots) and ground attack. While some fighter aircraft sent into Vietnam war didn’t have onboard cannons, low kill probabilities of missiles – especially long-range radar-guided missiles – resulted in guns being reintroduced. Another issue is that, even today, visual identification of target is the only reliable way of identifying it – and many fighter aircraft still do not have imaging IRST or other optical sensor capable of identifying targets at beyond normal identification range of several hundred meters. Read the rest of this entry »

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Fighter aircraft engine comparision

Posted by Picard578 on December 6, 2014

Introduction

This article will compare several engines used in modern fighter aircraft: EJ200 (Typhoon), M88 (Rafale B/C/M), RM-12 (Gripen A/B/C/D), F-135 (F-35A/B/C), F-119 (F-22A), F404-GE-402 (F-18C/D), F-414-400 (F-18E/F, Gripen E/F), AL-31F (Su-27, Su-30, J-11). Read the rest of this entry »

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Comparing modern fighter aircraft

Posted by Picard578 on August 30, 2014

Nature of air to air combat

“Those who cannot remember the past are condemned to repeat it.”

—G. Santayana

Fighter aircraft exist to destroy other aircraft, and allow other aircraft to carry out their missions without interference from enemy fighter aircraft. That being said, there exists a colloqial – and incorrect – use of term “fighter aircraft” as being applicable to any tactical aircraft, even those that are primarly or exclusively designed for ground attack, such as the A-10 and the F-35. Task of the aircraft is to enable pilot to bring weapons systems in position for a successful kill.

You never make a big truck and tomorrow make it a race car. And you never can make a big bomber and the next day a . . . fighter. The physical law means that you need another airplane. . . . You should do one job and should do this job good.

—Colonel Erich “Bubi” Hartmann, GAP Read the rest of this entry »

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Close coupled vs long arm canard

Posted by Picard578 on August 23, 2014

Canards overview and general effects

Canard is a small control surface placed in front of the main wing, similar to how tail is behind it. There are two main variations – long arm and close coupled canard.

Canard has a major advantage over the horizontal tail in the level flight. As aircraft passes through the transonic region, aircraft experiences an increased nose-down trim change. Control surface has to counter it; and while horizontal tail provides download, causing a large trim-drag penalty, canard can help provide upload, reducing need for elevon/tail trim and thus reducing level-flight drag. Further, canard also allows for an aerodynamically clean end of the aircraft with superior area distribution when compared to the tailed configuration, reducing supersonic drag.

Canard provides lift when aicraft is turning Read the rest of this entry »

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Saab Gripen vs F-35

Posted by Picard578 on March 16, 2013

AIRFRAME PERFORMANCE

Contrary to some claims, F-35 has rather simple and conventional aerodynamics. Basic configuration is similar to F-16, however lack of LERX, and use of lower-performance but stealth-friendly chimes for high AoA lift enhancement, means that it will have far less body lift than F-16 to help compensate for its high wing loading, and wing lift will also be smaller at high AoA. Result will be (for a modern fighter) disastrous turn rate.

Further, it has internal carriage, which adds drag compared to low-drag AAMs and pylons, and its far higher weight also means more inertia that has to be overcome.

Gripen is, on the other hand, built for maneuverability. Close-coupled canards, wing-body blending, and wing shape all help increase lift during maneuvers, allowing aircraft to both achieve higher angles of attack, and to turn tighter at same angle of attack. Particularly canards create vortices that reattach air flow to the wing at high angles of attack. Aside from helping air flow over the wing, Gripen’s canards also help air flow over the body. Canard also has advantage over tail as the control surface – as center of gravity for modern aircraft is towards rear of the aircraft, usage of canard results in longer moment arm than it is case with tail. Further, Gripen has large degree of wing-body blending, and it’s wing loading is also far lower than that of F-35.

While thrust-to-weight ratio is below 1 for both aircraft, Gripen has far lower drag than F-35, partly compensating for F-35s superior thrust-to-weight ratio. While F-35 achieves maximum of Mach 1,6, clean or not, Gripen can achieve speeds of over Mach 2 clean.

SITUATIONAL AWARENESS

First thing that can be noticed about both Gripen and F-35 is that neither has rearward visibility from cockpit. In Gripen’s case, attempt was made to attenuate the problem by installing rear-view mirrors onto the canopy forward frame. However, while Gripen’s visual and IR signatures are far lower than F-35s, Gripen itself does not have IRST, which means that F-35 may be able to detect it first.

WEAPONS

In gun department, Gripen uses German BK-27, a 27-milimeter revolver cannon which was also supposed to be equipped to F-35, but in the end, F-35 received 25-milimeter rotary-barrel GAU-22. In air-to-air combat, BK-27 has a large advantage over GAU-12 in that delay between pilot pressing the button and full rate of fire being achieved is just 0,05 seconds, as opposed to 0,4 seconds for GAU-22. Further, on F-35, trap door must open if gun is internal (and assuming it wasn’t open already), possibly adding another 0,5 seconds to process. Maximum rate of fire is 1 700 rpm for BK-27, and 3 300 rpm for GAU-22. Muzzle velocity is 1 025 m/s for BK-27 and 1 040 m/s for GAU-22, but BK-27s shells – weighting 260 g as opposed to GAU-22s 184 g for HEI and 215 g for AP – will bleed off speed slower, and be less affected by wind and other air turbulences.

Therefore, in first half of second – which is crucial in dogfight; rarely will opponent fly in the same directon for full second or more – BK-27 will fire 14 projectiles massing 3,64 kilograms, and GAU-22 will fire 16 projectiles massing 2,94 – 3,44 kilograms, but only assuming that F-35 pilot opened gun doors beforehand – if he didn’t, GAU-22 will not fire any projectiles at all. GAU-22 may be a sign that US have (finally) understood that 20 mm cannons are not sufficient for modern air-to-air combat, similar to WW2, when they delayed introduction of 20 mm cannons instead of 50 caliber machine guns as main fighter armament well into Korean War. However, it is more likely that it was thought of as compromise between air-to-air and air-to-ground combat, considering that F-35 is primarly ground attack aircraft.

FORCE PRESENCE AND SUPPORTABILITY

While F-35A costs 197 million USD flyaway, Gripen C costs 40 million USD flyaway. As such, Gripen can provide almost 5 times as large force as F-35A can. Further, due to Gripen’s lower maintenance and turnaround times, same force will be able to fly far more sorties. Gripen is also designed to operate from roads, and has STOL capability, something that F-35A lacks, though not the (even more expensive) F-35B.

5-TH GENERATION?

According to this article, Lockheed Martin’s definition of 5-th generation fighter is following:

— stealth
— high maneuverability
— advanced avionics
— networked data fusion from sensors and avionics; and
— the ability to assume multiple roles.

Comparing F-35 and Gripen, it can be seen that while F-35 is stealthier on radar, Gripen has far lower IR and lower visual signature. Unlike F-35, it also has high maneuverability, and both aircraft have advanced avionics and multirole capability, while networked data fusion will be avaliable on Gripen NG. F-22 has high maneuverability but is not multirole, while Rafale and Typhoon only lack stealth. Thus, F-22, F-35, Typhoon, Rafale and Gripen NG are all equally 5-th generation aircraft, with Gripen C/D being just one step away.

And while another article defines fifth generation fighter as “being able to operate in anti-access environment featuring integrated air defenses…”, that capability can also be achieved in several ways, radar stealth being just one aspect of survivability, and rather limited one considering proliferation of passive sensors.

Further reading

Comparing modern Western fighters

Comparing modern fighter aircraft

Dassault Rafale vs F-35

Fighter aircraft engine comparison

Fighter aircraft gun comparison

NATO main battle tanks comparison

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AIM-120D vs MBDA Meteor

Posted by Picard578 on December 15, 2012

Design requirements

AIM-120 was started as a project to replace painfully ineffective AIM-7 Sparrow and AIM-54 Phoenix (which are only effective against heavy bombers and (in case of later-iteration AIM-54) non-maneuvering fighters). It was to be relatively small BVR missile, so as to be able to be carried by the F-16.

Meteor is a result of joint European project to develop BVR missile to replace BAe Dynamics Skyflash. It was to be capable of shooting down a variety of targets, including low-RCS UAVs and cruise missiles, as well as maneuvering fighters of Flanker family. Another requirement was compatibility with Typhoon’s semi-recessed fuselage hardpoints, originally designed for AIM-120.

Effectiveness

AIM-120D is a further evolution of US AIM-120 BVR AAM series. It uses classic fuel+oxygen combustion mix, and does not rely on air flow from outside. In fact, it uses the same engine as AIM-120C, with improvements being mainly in electronics. However, it has been reported that engine malfunctions in cold environments – exactly where it is most likely to be used.

Meteor is a ramjet BVR AAM. As such, it does not carry onboard oxygen, but rather uses oxygen from surrounding air, allowing it to hold more fuel. Result is better acceleration, top speed, and range for a given missile size.

While Meteor may not have as large maximum range as AIM-120D (only figure I have for Meteor is “more than 100 km”, with 100 km being “optimal range”, versus public figure of 160 km for AIM-120D), it is faster, and thus more deadly at any range it can reach. This is important, as BVR missiles are never fired at maximum range due to meager Pk against fighter aircraft. However, range varies on altitude, with best range for both missile types being achieved in high-altitude rare-atmosphere conditions, where maneuverability is almost nonexistent; at sea level, range is not much more than visual. Velocity loss after burn-out also varies with altitude, with 25% of current velocity being lost every 150 s at 24 km, 25 s at 12 km and 5 s at sea level.

Range can be reduced even further if enemy uses jammers. Thus, large NEZ (no-escape zone) is far more important. (To explain terminology here, NEZ is NOT a zone where a hit is guaranteed; rather, it is a zone where enemy aircraft cannot outrun missile, waiting for it to run out of fuel, but rather has to outturn it). Higher speed allows it to reduce time to target, and thus opponent’s reaction time, as well as to retain energy for longer after engine has burned out.

In fact, Meteor’s NEZ was to be three times as large as that of AIM-120B. Active version of missile is equipped with radar Aster, designed to shoot down cruise missiles, which thus can be used against targets with low RCS.

However, both missiles are BVR, making their actual value questionable. In fact, jamming and IFF issues mean that BVR missiles are far more likely to be used as a WVR weapon than in their intended purpose. While AIM-120 did achieve 6 BVR kills out of 13 firings, all but one were against non-maneuvering targets with no ECM and no awareness of missile. By comparing difference in Pk between maneuvering and non-maneuvering targets for AIM-9, it can be concluded that AIM-120 will achieve Pk of at most 11%; however, it is larger and heavier than AIM-9, as well as more vulnerable to countermeasures, so even that is an optimistic estimate.

EDIT: Meteor is estimated to have a range of 250-300 km with ballistic flight path, which suggests an improvement over initially cited goal. That being said, best option is to wait for performance figures after it enters service.

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Aircraft combat presence comparision

Posted by Picard578 on December 8, 2012

Aircraft combat presence = total sorties per day = aircraft bought for a cost * sortie rate

Aircraft bought for 1 billion USD (using flyaway costs):

F-22: 4

F-35A: 5

EF-2000 T2 Luftwaffe: 9

EF-2000 T2 RAF: 8

EF-2000 T3 RAF: 8

Rafale C: 12

Rafale M: 11

F-15 A: 23

F-15 K: 10

F-16 A: 38

F-16 C: 16

YF-16: 62

F-18: 14

Gripen C: 25

Gripen E: 18 – 27

Sorties per aircraft per day:

F-35A: 3,5

F-35B: 6

F-35C: 4

(above figures are USAF estimates and are not reliable)

F-22: 0,5

F-35A: 0,6 (estimate)

EF-2000: 2,4

Rafale: 2,7

F-15: 1

F-16: 1,2

F-18: 1,2

Gripen C: 2,2

Gripen E: unknown, assuming 2-2,5

Total sorties per day for number of aircraft:

F-22: 2

F-35A: 2,5

EF-2000 T2 Luftwaffe: 21,6

EF-2000 T2 RAF: 19,2

EF-2000 T3 RAF: 19,2

Rafale C: 32,4

Rafale M: 29,7

F-15 A: 23

F-15 K: 10

F-16 A: 45,6

F-16 C: 19,2

F-18: 16,8

Gripen C: 55

Gripen E: 36 – 67,5

————————————–

As it can be seen, it is absurd to suggest that stealth aircraft are strenghtening defense of any country. In fact, more stealth aircraft means weaker combat capability, due to far smaller number of aircraft, as well as number of sorties single aircraft can perform in certain time, as opposed to the non-stealth aircraft. It is failure to find the balance between cost and performance that leads to the weaker defense, and F-22/F-35 projects can be rightly blamed for reduction of USAF’s combat capability.

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Is the F-22 really superior to all other fighter aircraft

Posted by Picard578 on December 1, 2012

USAF often touts F-22 as being the best fighter aircraft in the world. Is that really so? What are requirements for a good fighter aircraft?

By analyzing past wars we can see that following requirements have never changed:

  1. high agility at dogfighting speeds (currently in the medium subsonic to transsonic regime)
  2. superior situational awareness
  3. low cost
  4. high sortie rate
  5. capability to convert any split-second opportunity to the kill

High agility requires good acceleration, good turn rate, low energy loss and quick transients. Good acceleration and low energy loss require high thrust-to-weight ratio and low drag; good turn rate requires low wing loading, and quick transients require both. Energy state is important for gaining positional advantage and evading missiles.

Superior situational awareness requires not only having good situational awareness yourself, but denying it to the opponent. These requirements can only be met through use of passive sensors.

Low cost and high sortie rate are required for establishing a crucial numerical superiority over the opponent. Both are achieved by making the design as simple as possible.

Capability to convert any split-second opportunity to the kill is crucial in the dogfight, especially if multiple aircraft are involved on both sides, as it allows pilot to deny opponent the opportunity to reverse positional advantage, and allows him to kill more targets in the same timeframe.

With standard loadout of 50% fuel, 2 Sidewinder, 4 AMRAAM, F-22 has wing loading of 313,5 kg/m2 and thrust-to-weight ratio of 1,29. For comparision, with same loadout, Eurofighter Typhoon has wing loading of 284 kg/m2 and thrust-to-weight ratio of 1,28; Dassault Rafale’s values are 276 kg/m2 and 1,22. Su-27s values are 324 kg/m2 and 1,24. Thus, F-22 is inferior in wing loading to both Eurocanards, and has only slightly superior thrust-to-weight ratio compared to Typhoon. It is also only slightly superior to the Su-27 in wing loading, and somewhat more in thrust-to-weight ratio.

As such, it has slightly better turn rates than Su-27, and worse turn rates than Eurocanards. Its large weight will make it more difficult to F-22 to make transit from one turn to another, and its thrust vectoring will, if used, cause major energy losses. More about that later.

As mentioned, superior situational awareness requires not only having good situational awareness yourself, but denying it to the opponent. What this means is that aircraft must be capable of detecting and identifying the enemy completely passively. Currently, IRST and optical sensors are only types of sensors, except for Mk 1 eyeball, to posses such capability. F-22 lacks both, and as such has to either have an uplink to another platform – and such uplink can be detected and jammed – or to carry out both tasks World War II style, with pilot doing detection and identification visually. While F-22 was supposed to have FLIR, it was deleted as the cost-saving measure, and there are no plans to fit it.

Moreover, while some measures have been taken to reduce F-22s thermal signature, no major reduction was (or could have been) achieved, especially from the front. F-22 is also very large, increasing its detectability by the IRST. Thus, F-22 will be easily detected at ranges exceeding 80 kilometers by opponent using QWIP IRST.

Modern heat-seeking missiles also do not have to rely on engine exhaust for locking on the enemy aircraft, but can rather lock on to aircraft itself.

F-22 also isn’t undetectable to the modern radar, despite what some accounts say. While F-22s RCS of 0,0001 and 0,0014 m2 reduces detection range considerably, Typhoon’s radar (which has detection range of 185 km against 1m2 target) can detect it from distance of 18 to 35 kilometers. On the other hand, modern RWRs can detect LPI radars from ranges two or three times greater than such radars can detect target with RCS of 1 m2 at, thus making any use of radar an unwise course of action for F-22 (and any other fighter aircraft).

Low cost and high sortie rate are where F-22 feels least at home. Its flyaway cost is 250 million USD per unit, which is twice (205%) the flyaway cost of the most expensive non-VLO fighter aircraft – Eurofighter Typhoon – and has maintenance downtime of 45 hours per hour of flight, compared to the 8* hours for Rafale, 9* for Typhoon, 10 for Gripen and 19 for the now-ancient F-16 (* have to be confirmed). However, flyaway costs of these fighters, which are, respectively, 33%, 49%, 16% and 11-24% of F-22s, mean that it will be at 10:1 numerical disadvantage compared to Typhoon, and 26:1 disadvantage against Gripen.

F-22 is also incapable of converting split-second opportunities into kills. Reason for that is the fact that it carries all its armaments internally. It takes around half the second for gun doors to open; for missile bay doors it takes at least that much, and possibly more. Worse, Sidewinders it will be using in visual range dogfight are not simply ejected into air, but have to be lowered by mechanism; however, it is possible that such action will be performed while doors open.

Gun itself is the Gattling design. It offers maximum rate of fire of 6 600 rpm (110 rps), compared to 1 700 rpm (28 rps) for BK-27 used in Typhoon and Gripen, and 2 500 rpm (42 rps) for GIAT-30 used in Rafale. However, firing rate alone cannot be used as a measure of effectiveness.

First, Gattling gun takes some time to achieve full firing rate. While M-61A2 takes 0,25 seconds to spin up to its full firing rate, fact that F-22 has to open bay doors to fire increases that time to 0,75 seconds. For revolver cannon, time is 0,05 seconds. Thus, in first second, F-22 will have fired either 13 or 68 rounds (depending on wether gun doors were opened before or after press on trigger); Typhoon would have fired 27 rounds in the same time, and Rafale 40 rounds.

Second, aircraft now are highly resistant. Thus, per-hit damage and weight fired may be more important than number of projectiles. At projectile weight of 100 g for M-61, 260 g for Typhoon and 244 – 270 g for Rafale, F-22 fares worst in per-hit damage category. For total damage, in first second F-22 will have fired 1,3 to 6,8 kg, Typhoon 7 kg and Rafale 9,8 to 10,8 kg of ammunition.

Third, rotation of gun barrels creates vibrations, which means that Gattling design will be less accurate (more spread) than single-barreled designs, and problem will only increase as gun keeps firing.

While F-22 is supposed to kill opponent at BVR, it only carries 6 BVR missiles. With usual 0,08 Pk ratio against same-era threats, it will take two F-22s to kill a single enemy aircraft. That is made even worse by the fact that F-22 not only has to radiate in order to lock on the enemy aircraft, but has to get close enough to penetrate any jamming – distance that was regularly around 1/3 of maximum radar range; in F-22s case, it will be 50 – 80 kilometers against 1 m2 target, such as Typhoon or aircraft with comparable frontal RCS (J-10?) in air-to-air configuration.

F-22s maximum speed of Mach 1,8 – 2,25 and supercruise speed of Mach 1,5 – 1,7 are better than those of most competitors, as Eurofighter Typhoon – the second-fastest supercruiser – can achieve “only” Mach 1,3 when in combat configuration. Thus, F-22 can choose to run if it finds itself outnumbered too much, but if it does choose to attack, it will most likely be forced to engage the opponent in the visual range.

How maneuverable F-22 is

Many say that F-22 is the most maneuverable fighter aircraft by virtue of its thrust vectoring. So, I have decided to take a closer look at various claims about F-22s agility.

F-22 is the most maneuverable fighter aircraft out there

Some claim that F-22 is the most maneuverable and agile fighter aircraft out there, due to the thrust vectoring. That claim, however, is false.

To execute a turn, aircraft requires lift to pull it around the turn. Even civilian jets make sharper turns this way, by banking. Amount of lift can be roughly estimated through wing loading figures, with the caveat that LEX and close-coupled canards do provide the additional lift during high-alpha maneuvers by strengthening vortices created by the wing.

However, while F-22 does have LEX, it is not the only one. Dassault Rafale has both LEX and close-coupled canards, Saab Gripen has close-coupled canards, and Eurofighter Typhoon, while not having either, does have vortex generators at sides of the fuselage.

Thus, actual lift at high AoA could be estimated by comparing length of forward portion of the wing to the aircraft’s weight. This method is only of limited accuracy, however, it is more accurate than standard wing loading figures for high alpha maneuvers, as large portion of wing stalls in such circumstances.

F-22 has combat weight of 24 883 kg and combined wing leading edge length of cca 12,58 meters, which becomes 20,56 meters when LEX and air intake leading surface are taken into account. Thus loading value will be 1210 kg per meter. However, LEX-generated vortices will improve value.

Eurofighter Typhoon, on the other hand, has combat weight of 14 483 kg and combined wing leading edge length of ~18,3 meters along with canards. Thus its loading value will be 791 kg per meter, or slightly higher, but as with F-22, vortices will improve value – this time vortices generated by strakes at sides of Typhoon’s hull. Both Typhoon and F-22 have similar wing sweep and high-lift devices, so actual lifting area per meter will be the same, except maybe for canards.

At lower angles of attack, when entire wing area is used, F-22 will have wing loading of 319 kg/m2 in standard combat configuration, and Eurofighter Typhoon will have wing loading of 283 kg/m2. Thrust loading ratios will be 1,28 for F-22 and 1,25 for Eurofighter Typhoon.

We can thus see that, while F-22 has thrust-to-weight ratio advantage, Eurofighter Typhoon has both lower combat weight and lower wing loading at combat weight, and thus has better maneuvering performance. Dassault Rafale will have similar advantages, although its canards act more like F-22s LEX, which makes it for two aircraft that have better maneuvering performance than F-22.

F-22 is comparable to F-15C (claim made by Pierre Sprey)

Comparing it to the F-15C, we see two things: wing loading and thrust-to-weight ratio that are very similar, with F-15C having slight advantage. While F-22 is larger and heavier aircraft, it is also unstable, improving its response time and removing resustance of aircraft towards the continued turn. It also has LEX, which improves lift at high angle of attack.

While its internal missile carriage adds weight and frontal area, that is cancelled out by reduced drag due to lack of external stores.

F-22 is worse than F-16

F-22 and F-16 have two major things in common: both are relaxed-stability designs and both have LEX. As such, similar wing loading figures and thrust-to-weight ratios will result in similar maneuverability, especially since F-16 was designed to achieve optimum performance when two wingtip AAMs are present.

With 50% fuel, 2 Sidewinder and 4 AMRAAM F-16C has wing loading of 392 kg/m2, thrust-to-weight ratio of 1,186 and weights 10 936 kg. F-22 has wing loading of 313,5 kg/m2, thrust-to-weight ratio of 1,29 and weights 24 579 kg. Thus, while F-22 will suffer maneuverability penalty due to its size and weight, it is unlikely that F-16C will be able to outmaneuver it.

With F-16A it is a different story. With empty weight of 7 076 kg, it has wing loading of 349,5 kg/m2 and thrust-to-weight ratio of 1,29 (figures for 50% fuel and 2 Sidewinder). While its wing loading is higher than F-22s, F-16A is far lighter and smaller, so it is possible that it could be capable of matching the F-22.

Conclusion

To conclude, while Pierre Sprey’s notion that F-22 is no more maneuverable than F-15C is not supportable, those that insist F-22 is the most maneuverable fighter aircraft in the world are equally wrong. Indeed, new fighters such as Eurofighter Typhoon or Dassault Rafale will have better maneuvering performance with virtue of their better aerodynamics and superior attributes (wing loading, thrust-to-weight ratio, etc). F-22 also does not meet force size requirements.

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Comparing options for Australia

Posted by Picard578 on December 1, 2012

Some claim that Super Bug is a better solution than F-35 is… some claim that it is not. So I have decided to carry out point-by-point comparision between F-18E and F-35, throwing in Tranche 2 Eurofighter Typhoon and Rafale C as examples of modern Western fighter, as well as possible alternatives.

What makes this comparision even more important is the fact that United States, Canada and Australia all have similar operational requirements and as such have very similar requirements for a fighter aircraft – for example, long range, twin engines and reliability.

Source for F-35 data is here.

Table

Aircraft F-18E F-35A F-35B F-35C EF-2000 T2 Rafale C
Length 18,31 m 15,7 m 15,6 m 15,7 m 15,96 m 15,27 m
Wing span 13,62 m 10,7 m 10,7 m 13,1 m 10,95 m 10,8 m
Height 4,88 m 4,6 m ? ? 5,28 m 5,34 m
Wing area 46,5 m2 42,7 m2 42,7 m2 62,1 m2 51,2 m2 45,7 m2
Weight with 50% fuel, 2 Sidewinder, 4 AMRAAM 18 721 kg 18 208 kg 18 491 kg 21 043 kg 14 427 kg 11 850 kg
Wing loading
– loaded 458,5 kg/m2 526 kg/m2 506 kg/m2 410 kg/m2 312 kg/m2 307 kg/m2
– 50% fuel, 2 Sidewinder, 4 AMRAAM 402,6 kg/m2 427,9 kg/m2 434,2 kg/m2 338 kg/m2 284 kg/m2 259,3 kg/m2
Thrust-to-weight ratio
– loaded 0,94 0,87 0,9 0,75 1,15 1,1
– 50% fuel, 2 Sidewinder, 4 AMRAAM 1,07 1,07 1,05 0,93 1,28 1,3
Maximum AoA 55* 50* 50* 50* 70* 100*
Speed
– dash M 1,8 M 1,6 M 1,6 M 1,6 M 2 M 2
– combat configuration dash ? M 1,6 M 1,6 M 1,6 M 1,8 M 1,8
– cruise M 1 M 0,95 M 0,9+ M 0,9+ M 1,8 M 1,8
– combat configuration standard cruise ? M 0,9 ? ? M 1,6 (est) M 1,6 (est)
– combat configuration supercruise N/A N/A N/A N/A M 1,3 M 1,4
Combat radius 722 km 1 082 km 868 km 1 139 km 1 389 km 1 852 km
Max G (standard) 7,6 9 7 7,5 9 9
Max G (override)* 11 11
Max G (airframe) 11,4 13,5 >=10,5 11 12,6 – 13,5 16,7
Max G reached in tests or use ? 9,9 ? ? 10,6 11
Instanteneous turn rate (max) 24 deg/s <14 deg/s ? ? 30-35 deg/s 32-35 deg/s
Sustained turn rate (max) 15-18 deg/s <12 deg/s ? ? 20-25 deg/s 24 deg/s
Roll rate (max) 120 deg/s 300 deg/s ? ? 240-250 deg/s 270 deg/s
Flyaway cost 60 000 000 197 000 000 237 700 000 236 800 000 118 600 000 82 300 000

*can be exceeded through changes to FCS

Maneuverability

Maneuverability is a sum of several factors: lift, thrust, drag, and inertia. Lift, thrust and inertia can be compared through wing loading, thrust-to-weight ratio, and weight; drag can be compared by comparing airframes’ physical size.

Turn is executed when aircraft uses control surfaces to change wing’s position relative to the air flow; thus, direction in which lift pulls aircraft is changed, producing excess lift (one not used on keeping aircraft in the air), which then pulls aircraft around the turn. Aircraft with lower wing loading have more excess lift on disposition, and as such can pull faster and tighter turns. Aircraft pulling tighter turn at corner speed has better chance to evade missile fire and can pull inside opponent’s turn diameter.

Roll is when aircraft rotates around longitudinal axis. Aircraft with faster roll can transit from one maneuver to another faster.

Thrust-to-weight ratio is important for overcoming drag during the turn, allowing aircraft to maintain energy and turn rate for longer time.

Drag bleeds off energy, thus reducing time during which turn rate can be maintained.

Inertia is a product of weight and speed. When entering or exiting a turn, aircraft has to use lift and thrust to counter inertia. Thus, heavier aircraft are, assuming identical wing loading and thrust loading values, more sluggish in maneuvering combat.

G-load is required so that aircraft does not fall apart during the turn. What it means is that, even if (aerodynamically) aircraft could turn faster at certain speed, it is limited by what its structure can take.

As we can see from the table, Super Bug is superior in both wing loading and G factor to two out of three F-35 variants. It also has superior thrust-to-weight ratio to all F-35 variants when loaded for air combat, and only F-35A has comparable thrust-to-weight when at 50% fuel. It is, however, slightly heavier than most F-35 variants, which means more inertia and thus worse response time.

Eurocanards, meanwhile, are superior to both Super Bug and F-35 in all listed areas. Rafale fares better in wing loading and thrust-to-weight ratio areas than Typhoon does, mainly by virtue of its higher fuel fraction, and its close-coupled canards allow it to achieve highest AoA value of all compared aircraft, which greatly benefits its low-speed agility. Only characteristic where F-35 is superior to Eurocanards is roll rate, mainly due to its shorter wing span.

Situational awareness

Here, Super Bug is convincingly the worst of the compared aircraft, as it lacks IRST. As such, it has to use its radar to detect the enemy, immediately betraying its location at far longer range than it itself can detect the opponent. All three other aircraft have IRSTs of, apparently, roughly comparable characteristics.

Range

Here, Super Bug takes last place again. Rafale has the best range, owing to its good aerodynamics and high fuel fraction. Whereas some F-35 variants have comparable or better fuel fraction, their low speed and large aerodynamic compromises required by stealth mean that range is lowered considerably, and is worse than that for Eurofighter Typhoon, which itself has low fuel fraction.

Weapons loadout

Standard weapons loadout for all listed aircraft is 2 Sidewinders and 2-6 AMRAAM. However, F-35 has no option of carrying more without compromising its already questionable X-band radar stealth, whereas other aircraft don’t go to such legth to achieve LO characteristics, relying instead on other approaches (maneuverability + countermeasures + passive sensors). Thus, F-35 is limited to 4 missiles if it doesn’t want to loose radar stealth, whereas Super Hornet can carry 6, Eurofighter Typhoon 12 and Dassault Rafale 8-10 AtA missiles. In non-LO configuration, F-35 can carry 10 missiles.

In bombing missions, F-35 can carry 2 AtA and 2 AtG weapons in LO and 4 AtA and 8 AtG weapons in non-LO configuration. Super Hornet can carry 4 AtA and 7 AtG weapons. Typhoon can carry 7-9 AtG weapons, assuming all stations are cleared for use. Rafale can carry 4 AtA and 5-16 AtG weapons.

As F-35 has to rely on LO, its AtA and AtG weapons loadouts are the worst. If LO requirement is ignored, weapons loadout improves considerably, but only to the point of being barely comarable to that of far lighter Eurocanards in AtA configuration; in AtG configuration, assuming one weapon = one pylon, it is the best of compared aircraft, in keeping with its design role of a bomber.

Cost and battlespace presence

As it is obvious, situation is not good for F-35: for a cost of the 12-aircraft squadron, one can buy 19 Typhoons, 28 Rafales, or 39 Super Hornets. All three aircraft, especially Eurocanards, are likely to be less maintenance-intensive than F-35, and can thus generate more sorties per aircraft, thus increasing numerical disparity even more.

Per-aircraft, Super Hornet requires 10 maintenance hours per flight hour, Typhoon requires 9 and Rafale 8 (? Typhoon and Rafale figures have to be confirmed), meaning that bought aircraft will generate 85 1-hour sorties per day for Super Hornet, 45 for Typhoon and 74 for Rafale. Aforementioned 12-ship F-35 squadron will most likely be able to generate 7 to 8 1-hour sorties per day. However, Rafales and Typhoons will have better survivability when facing both VHF-radar SAMs and IRST-equipped enemy aircraft than either Super Hornets or F-35s.

Conclusion

Neither F-35 or Super Hornet are good choices for Australia; former is too expensive, too maintenance-intensive, too short-ranged and lacking in maneuverability, whereas latter is far cheaper to buy and operate, and easier to maintain, but is also lacking in range and maneuverability. All options considered, Dassault Rafale would be the best choice, followed by the Eurofighter Typhoon. However, with Dassault having secured contract in India, it is questionable wether acquirement schedule for Australia could be accomodated, in which case Typhoon becomes the strategically better choice.

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