Good metrics to measure fighters with


In 1982, weapon systems analyst Pierre Sprey published a study briefly narrating air-to-air combat from World War 1 to the 1970s and outlining on that basis what he believes are the characteristics and capabilities a fighter must have to prevail in air combat. By that yardstick, he then measured a number of fighters that were then in service, in development, or had been retired from service some years earlier. I’ve read the study and I must say that, except his requirement that one must outnumber the enemy, his criteria are valid and constitute a very good – perhaps even the best – yardstick to measure fighters with. Specifically, Sprey wrote that to prevail in combat against other fighters, the aircraft a nation decides to procure must be able to (in that order of importance):

  • Surprise the enemy by detecting him before he detects that aircraft, positiong itself behind the enemy’s rear (his weakest point, usually a blind spot), and shooting him down by surprise (80% of all fighters shot down in wars from WW1 to the 1970s went down without their crews knowing what hit them);
  • Outnumber the enemy;
  • Outmaneuver (outaccelerate, outdecelerate, outclimb, and outturn) the enemy and transition from one maneuver to another more seamlessly than he can; and
  • Outlast the enemy and run him out of fuel if the fight is prolonged.

The requirement that one must outnumber the enemy is not valid. If numbers were the key to victory, let alone the second most important characteristic of fighters as Sprey claims, then virtually every war in history should’ve been won through sheer numbers. If that were the case, the RAF would’ve never been able to defeat the much larger German fighter fleet in the Battle of Britain, the Israeli AF would’ve been utterly trounced by its Arab counterparts in the Six Day and Yom Kippur Wars (and Israel would’ve probably ceased to exist, as its Arab neighbors wish), and the small global fleet of F-15s would’ve been utterly trounced by its foreign opponents. This is not to say that a small fleet of “silver bullet” aircraft will suffice to defeat the enemy. Eventually, he’ll be able to overwhelm the “silver bullet” fleet with sheer numbers. But numbers are not the decisive factor in air to air warfare, let alone the 2nd most important factor. But Sprey’s other three requirements are absolutely correct. Common sense alone validates most of them. So does Sun Tzu, the greatest military mind in history, who believed you should always try to take the enemy by surprise, and when you can’t, you should outmaneuver him. (He did not believe, however, that having greater numbers gives one any advantage, and he was opposed to prolong fights. History proved him right and Sprey wrong.) So, modern fighters compare to each other by Sprey’s yardstick like this:

  • The best fighters, by his criteria, are the Dassault Rafale and the Typhoon. They’re small and thus difficult to see visually. They don’t emit much heat, so they’re hard to detect with IR sensors. Smoke is not an issue with them. Very maneuverable, they have a good rate of climb (60,000 ft per minute in the Rafale’s case, 62,000 ft/min for the Typhoon), very low wing loading, high thrust/weight ratios, and can thus outturn the enemy; and being light, they can transition from one maneuver to another seemlessly. They also have IRSTs  – and lots of fuel to burn, and can thus outlast the enemy.
  • Their only weakness, such as it is, is they can fly no faster than Mach 2. However, that’s a speed most fighters never fly at, except for a few seconds perhaps. Both the Rafale and the Typhoon have supercruise capability, meaning they can cruise efficiently at supersonic speeds without using fuel-gulping, superhot afterburners.
  • The Gripen is even smaller, lighter, and more maneuverable, but its very low ceiling and top speed, and short combat radius, let it down significantly. An enemy could run a Gripen out of fuel, or outrun it, easily. It also carries a puny weapons load (8 missiles).
  • The F-16 is better than the Gripen. Its only weaknesses are: a very short combat radius (550 kms), the risk of being run out of fuel, and the fact it doesn’t have supercruise capab. and can’t fly faster than Mach 2. It also lacks an IRST. But the F-16 should, in most cases, be able to defeat the enemy without prolonged fighting. The same applies to the even lighter, more maneuverable F-5, which has repeatedly ran F-15s out of fuel.
  • The J-35 Draken, the Mirage III and 5, and the F-86 are too old to take into account. However, they were highly maneuverable, nimble, simple, and cheap aircraft. Older pilots of Israeli Air Force have said of all fighters they’ve ever flown, the best was the Mirage III – which the IAF liked so much, it developed its own variants of it.
  • The MiG-29 is as good as, if not better than, the F-16. It flies and climbs faster, is almost as good at turning, has a better combat radius, and is of roughly the same size. It is a far, far better fighterplane than it gets credit for being.
  • The Flankers are (excepting the Su-33) very maneuverable, have good rates of climb, lots of weapons, lots of fuel to burn, long combat radii, and lots of diverse countermeasures. However, they are big and hot, and thus easy to see visually and with IRSTs, esp. if they light up their radar (which will also give their position away thanks to RWRs).
  • Also, their climb rates and wing loading (again, excepting the Su-33, which is downright pathetic) are still inferior to those of the Rafale and the Typhoon, as well as the MiG-29). By the latter measure, they’re also inferior to the F-15, F-22, and F-16. The J-11 and J-16 gain on the Rafale/Typhoon duo with a climb rate of 300-305 metres/second, and the J-15 naval fighter overtakes them at 325 m/s. It is currently the best naval fighter in the world and will easily trounce the F/A-18 A thru F.
  • So how does the “Super Hornet” compare to its Chinese counterpart (or to the Rafale and the Typhoon)? Pathetically.
  • It has a climb rate of just 228 m/s; a wing loading of 459 kg/sq m; a T/W ratio of just 0.93; an inability to sustain more than 7.6Gs; and a top speed of just Mach 1.8 compared to Mach 2.35 for the J-15. Also, its engines smoke as badly as those of the F-15 and the now-retired F-14 “Tom Turkey”, to which it is also decisively inferior.
  • The F-15 and the F-22 are very fast, fly very high, and carry lots of missiles. The F-22, in addition, is stealthy and supercruising. But they are big and thus easy to see visually from at least 5 miles; very hot (though there are IR sig reduction measures on the F-22); and the F-15’s engines emit a lot of smoke, making it even easier to see, while the F-22 lacks an IRST and relies on its radar as its sole sensor. This is a huge mistake; the moment you light your radar up, you’re a dead duck because the enemy, thanks to his RWR, will know where you are and who you are (US radar operates at completely different frequencies and wavelengths than Russian radar). If you lock on a radar-guided missile on the enemy, he’ll know a launch is imminent and will duck it.
  • The MiG-21 is very light, maneuverable, and as fast as an F-16, but it can’t carry much ordnance, has little fuel to burn, and its pilot lack rearward visibility, bc the MiG-21 was designed as an interceptor in the belief that dogfighting was obsolete. The Indian AF’s MiG-21 fleet was completely trounced by the Pakistanis, flying the Mark VI Sabre, in 1971… 21 years after the Sabre first saw combat over Korea.
Bottom line: smaller, lighter, more maneuverable, well-armed fighters, if they have enough fuel to outlast the enemy, can trounce bigger, more complex, more expensive fighters. The key to prevailing in air combat is not stealthiness or who has the biggest, most capable radar, or who flies the fastest and the highest. The key is surprise, maneuverability, and outlasting the enemy. And by that yardstick, the Rafale and the Typhoon have only two peers: the MiG-29 and the J-15 Flying Shark.

One thought on “Good metrics to measure fighters with”

  1. “The requirement that one must outnumber the enemy is not valid.”

    It is not decisive, but it is important. You know how German Me-262s had little effect, even though many were piloted by surviving aces? They were outnumbered, which meant that Allied P-51s and Spitfires could wait at known German air bases, and shoot down Me-262s as they took off.

    That being said, numerical advantage is useless if pilots flying these aircraft do not have the skill necessary to capitalize on it – which is why I often point out high reliability, easy maintenance and low operating costs as possibly *the* most important fighter’s characteristics, and that training should not be sacrificed even if it means that fewer aircraft can be bought. Better to have 24 fighters whose pilots fly 40 hours per month than 48 fighters whose pilots fly 20 hours per month.

    “The best fighters, by his criteria, are the Dassault Rafale and the Typhoon. They’re small and thus difficult to see visually. They don’t emit much heat, so they’re hard to detect with IR sensors. Smoke is not an issue with them. Very maneuverable, they have a good rate of climb (60,000 ft per minute in the Rafale’s case, 62,000 ft/min for the Typhoon), very low wing loading, high thrust/weight ratios, and can thus outturn the enemy; and being light, they can transition from one maneuver to another seemlessly. They also have IRSTs – and lots of fuel to burn, and can thus outlast the enemy.”

    I should point out here few differences between them:
    1) Rafale has better ability to surprise the enemy since it is smaller, has extensive IR signature reduction measures (including a second cooling channel around the engine, and, if memory serves me well, an IR absorbent paint) and has completely passive MAWS. Only Typhoon’s advantage in this regard is superior IRST.
    2) Rafale has far better transient performance (turn onset, roll onset, instantaneous turn rate) than Typhoon due to its close coupled canard layout; Gripen also has better transient performance than Typhoon, though its acceleration is inferior.

    “Their only weakness, such as it is, is they can fly no faster than Mach 2. However, that’s a speed most fighters never fly at, except for a few seconds perhaps. Both the Rafale and the Typhoon have supercruise capability, meaning they can cruise efficiently at supersonic speeds without using fuel-gulping, superhot afterburners.”

    Here, Typhoon has a Mach 0,1 advantage in the cruise speed.

    “The F-16 is better than the Gripen.”

    Actually, no. It has better rearward visibility and acceleration, but it has inferior instantaneous turn rate and transient performance, as well as inferior cruise speed (Mach 0,9 compared to Mach 1,1 for Gripen A and 1,05 for Gripen C).

    “The J-35 Draken, the Mirage III and 5, and the F-86 are too old to take into account. However, they were highly maneuverable, nimble, simple, and cheap aircraft. Older pilots of Israeli Air Force have said of all fighters they’ve ever flown, the best was the Mirage III – which the IAF liked so much, it developed its own variants of it.”

    Mirage IIIO could also cruise at Mach 1,3, though I believe it could only do so without any missiles.

    “It is a far, far better fighterplane than it gets credit for being.”

    Its problem is that only versions that ever saw combat were export “monkey” versions piloted by undertrained pilots.

    “US radar operates at completely different frequencies and wavelengths than Russian radar”

    8-12 GHz, if I remmeber correctly, due to the all-weather requirement.

    “The MiG-21 is very light, maneuverable, and as fast as an F-16, but it can’t carry much ordnance, has little fuel to burn, and its pilot lack rearward visibility, bc the MiG-21 was designed as an interceptor in the belief that dogfighting was obsolete.”

    It also has sharp, highly-swept wings which leads to bad airfield performance.

    “Bottom line: smaller, lighter, more maneuverable, well-armed fighters, if they have enough fuel to outlast the enemy, can trounce bigger, more complex, more expensive fighters. The key to prevailing in air combat is not stealthiness or who has the biggest, most capable radar, or who flies the fastest and the highest. The key is surprise, maneuverability, and outlasting the enemy. And by that yardstick, the Rafale and the Typhoon have only two peers: the MiG-29 and the J-15 Flying Shark.”

    Agreed, and one note here: persistence is best measured by the fuel fraction and not total fuel capacity, although fuel fraction itself is not entirely indicative, since fighter with better thrust-to-drag and lift-to-drag ratios can stay in low afterburner, or even at dry thrust, while letting their lower-performance opponent gulp fuel by gallons in full afterburner (which is why Rafale will always outlast the F-35 in dogfight despite latter’s higher fuel fraction).

    I’m just writing a revised version of my “comparing modern Western fighters” article, BTW.

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