Why fighters primary attributes changed the way they did?

[Vanessa1402]

In World War I, the primary/ priority attribute of fighter is turn rate, better turn rate make better fighters
In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47
In the 1960-1970s, the priority become top speed, acceleration, BVR Ex: F-4
In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16
so what make turn rate important again in the 1980-1990s ? why zoom and boom tactic no longer effective?

 

[Justo Miranda]

In World War I, the primary/ priority attribute of fighter is turn rate, better turn rate make better fighters
In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47
In the 1960-1970s, the priority become top speed, acceleration, BVR Ex: F-4
In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16
so what make turn rate important again in the 1980-1990s ? why zoom and boom tactic no longer effective?

Because in the eighties the main enemy was missiles, combats between fighters armed with cannons was not frequent

 

[Archibald]

Vietnam. Definitively.

The Phantom armed with AIM-7B Sparrow essentially tried, in 1960, to leapfrog a generation and go straight to
- F-15A with AIM-7E, 1980
or
- F-15C with AMRAAM, 1995
Speaking generally of course. What I mean: screw the guns & visual range & dog fight; medium-range, BVR shot with AAM.

Ok ?

And then Vietnam happened, and the combination of Phantom + AIM-7B/C/D proved disastrous.
- friendly fire
- AIM-7 before E/F did not worked well

and since early sidewinders didn't worked too well, the big Phantom found itself hastily loaded with a 20 mm gun, trying to fight nimble MiGs - with mixed results.

"Top gun" was a early answer to that.

Then come Boyd "fighter mafia" leading to the 1975 F-16A: ultra-agile, one gun, 2 improved AIM-9s.

An improved, US MiG-21 / Mirage IIIC.

In parallel the Phantom was "reborn" as the F-15A with a much improved Sparrow AIM-7E/F) and AMRAAM was started. Drawing from Phantom Vietnam negative experiences, this time it worked. The technology just had to mature for 20 years: 1960, NO, 1980: YES.

By 1990, back to "Phantom Square one": medium-range BVR AAMs - and from there, to present day fighters.

 

[DWG]

In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility. These were a problem for less agile, aircraft if you tried to engage them on equal terms in a manouevring fight. Boom and zoom was a defensive reaction by less agile aircraft, trying to minimise their exposure to the better turn rate of the opposing aircraft, but the vulnerability of the agile aircraft, and generally heavier armament of the fighters forced to engage in boom and zoom, meant that a defensive tactical innovation actually gave them an offensive advantage

IOW it wasn't an intentional change in aircraft design, it was a change in tactics forced by the strengths of the opposing aircraft - something which is emphasized by the designs of most of the boom-and-zoom focused fighters actually predating the recognition of the strengths of the opposing aircraft. The P-51 was built to be a North American equivalent to the P-40, that would allow NA to meet the RAF's P-40 order without actually building P-40s. Adding the superior Merlin to American V1710 powered fighters to make them better at higher altitude was an obvious improvement. Meanwhile the P-47 was just a continuation of design trends already visible in the Republic P-43. Both designs pre-date Pearl Harbour and the recognition of the strengths of the Japanese aircraft as agile dogfighters.

And to the strengths and weaknesses of the aircraft we have to add the strengths and weaknesses of the respective training and industrial regimes. Both the Japanese and Italian air forces taught their pilots to focus on agility, they were indoctrinated that dogfighting in agile aircraft was the one route to success as a fighter pilot. On top of which the Axis regimes universally had pilot training programmes that were poorly structured to 1) deal with a long war and 2) integrate the lessons that emerged into training the next generation. Allied pilots faced with the Zero (even when it was actually a Ki 43) had to innovate to survive, because if they fought the Zero on its terms, it was going to win. And when the Italians and, more reluctantly the Japanese, began to realise that the day of the lightweight agile fighter was over, their industrial strengths weren't up to replacing them with heavier fighters quickly enough.

 

[DWG]

In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16

so what make turn rate important again in the 1980-1990s ? why zoom and boom tactic no longer effective?

The core issue for the F-16 is that John Boyd* and the Fighter Mafia were a bunch of anachronistic idiots who thought it was still 1951. They temporarily gained influence in DoD, which lead to the creation of the F-16 as a lightweight dayfighter intended to be able to take on the MiG-15 in a turning fight over Korea. Fortunately people realised the Emperor Had No Clothes and started trying to fix the F-16 before it ever reached production. Even the F-16A was a heavier, better equipped, less agile fighter than Boyd had intended, and it still needed a second generation in the even heavier, even less agile F-16C to bring it up to 1980s spec. The F-17, originating from the same requirement, had similar weaknesses, but benefitted from being reworked into the F-18 to add carrier capability, and still needed a second generation, and then a growth version, and still doesn't meet some of the F-18's design requirements.

All other Western 1980s/90s designs have a completely different design genesis to the F-16/-17/-18. They were intended to be missile fighters from the outset, and to evade the merge by using sustained turn rate to turn away after launching BVRAAMs. The advent of FBW meant that they could also have superb instantaneous agility if they were forced to dogfight, but that was never the intention for how they should fight.

* Which is not to devalue Boyd's other work, the irony is that he was an idiot looking at operational needs in his own field, but a genius in drawing operational lessons in other people's.

 

[Ainen]

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility.

a6m doesn't fit into this list.

 

[DWG]

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility.

a6m doesn't fit into this list.

Care to specify how? It was agile, lightly armed, and vulnerable.

"I don't think I have ever flown a fighter that could match the rate of turn of the Zero. The Zero had ruled the roost totally and was the finest fighter in the world until mid-1943."

Captain Eric Brown

 

[overscan (PaulMM)]

In World War I, the primary/ priority attribute of fighter is turn rate, better turn rate make better fighters
In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47
In the 1960-1970s, the priority become top speed, acceleration, BVR Ex: F-4
In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16
so what make turn rate important again in the 1980-1990s ? why zoom and boom tactic no longer effective?

Your analysis is very US-centric. DWG has given some examples of how you have to account for the strengths and weaknesses of the adversary,

 

[riggerrob]

Think about fighter evolution in terms of ranges of weapons.
During World War 1, most fighters were only equipped with 1 or 2 rifle-calbre (e.g. German 7.92 mm) machineguns.
By mid-World War 2, most fighters sported heavy machineguns (e.g. American Browning .50") or 20 mm auto-cannons.
They still used auto-cannons (20 or 30 mm) during the Korean War.
During the Vietnam Wat, they (e.g. USAF) tried to convert to missile-only fighters, but missiles were not reliable enough and required the attacking fighter to get on the tail of his target. Therefor, F-4 Phantoms were retrofitted with 20 mm auto-cannons.
By the time of the Gulf War, missiles were reliable enough for firing beyond visual range.
Then missiles learned how to turn faster than any fighter. To improve off-bore-sight firing, Heads up displays were added to fighter pilots' helmets.

On the issue of ground attack, similar progression except that early A-10 relied on its 30 mm auto-cannon to kill Communist tanks. When hardly any Soviet tanks fought in Afghanistan, they switched to precision-guided bombs which allowed them to orbit high above AAA ranges and drop during bad weather. IOW by late in the Afghan War, A-10s no longer had to descend low enough to risk being shot down by Taliban heavy machineguns (14.5 mm).

 

[Vanessa1402]

In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility. These were a problem for less agile, aircraft if you tried to engage them on equal terms in a manouevring fight. Boom and zoom was a defensive reaction by less agile aircraft, trying to minimise their exposure to the better turn rate of the opposing aircraft, but the vulnerability of the agile aircraft, and generally heavier armament of the fighters forced to engage in boom and zoom, meant that a defensive tactical innovation actually gave them an offensive advantage

so if I understand you corectly, the reason boom and zoom aircraft such as P-51, P-47, FW190 , TA-152 will survive better than turn and burn aircraft such as A6M, Ki-43, Splitfire is mainly due to the fact that they are more heavily armed and heavily armored? (since they don't have to reduce weight? ). Is that a correct?.
And the reason boom and zoom doesn't work (or much less effective) on fighter jet, such as F-14, F-15, F-16 is because they are equally lightly armed and equally lightly armored? Is that correct?. Does that make F-14 better than F-16 in WVR combat? because F-14 has superior turn rate why F-16 has superior acceleration
Is boom and zoom the same as fighting in the vertical?

 

[Vanessa1402]

In World War I, the primary/ priority attribute of fighter is turn rate, better turn rate make better fighters
In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47
In the 1960-1970s, the priority become top speed, acceleration, BVR Ex: F-4
In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16
so what make turn rate important again in the 1980-1990s ? why zoom and boom tactic no longer effective?

Because in the eighties the main enemy was missiles, combats between fighters armed with cannons was not frequent

so boom and zoom was not effective because you can't out accelerate a missile?

 

[trose213]

In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16

The 80s-90s was definitely still BVR becoming more mature.

 

[red admiral]

So boom and zoom was not effective because you can't out accelerate a missile?

Basically yes. You can extend through the merge but if the other aircraft has sufficient turn rate and rear aspect missiles then its pretty difficult to extend out of missile range in the time its taken the other aircraft to turn through 150-180 degrees. This gets harder with missiles that you can shoot further and further off boresight. And even harder if you've got an all-aspect laser.

 

[Vanessa1402]

So boom and zoom was not effective because you can't out accelerate a missile?

Basically yes. You can extend through the merge but if the other aircraft has sufficient turn rate and rear aspect missiles then its pretty difficult to extend out of missile range in the time its taken the other aircraft to turn through 150-180 degrees. This gets harder with missiles that you can shoot further and further off boresight. And even harder if you've got an all-aspect laser.

That sort of make sense, however, if that is the case, then why fighter such as F-15, F-16 emphasized sustained turn rate and acceleration rather than instantaneous turn rate like F-14 and Mirage 2000?. And why TVC wasn't very popular in the West?. If you can't out accelerate missile then the best course of action in WVR combat will be pointing your nose at enemy first

 

[Ainen]

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility.

a6m doesn't fit into this list.

Care to specify how? It was agile, lightly armed, and vulnerable.

"I don't think I have ever flown a fighter that could match the rate of turn of the Zero. The Zero had ruled the roost totally and was the finest fighter in the world until mid-1943."

Captain Eric Brown

1. IJN tactics were ironically energy fight-centric. The ability to do a turn fight doesn't change that fact. Later on, they simply didn't have this choice anymore.
Consequently, A6M wasn't optimized just for agility. It was optimized(put on a diet) for literally everything. Compare it with contemporary(1940-41-42) carrier-borne fighters - it is not just "agile"(a5m was more agile, and biplanes were more agile still). it was faster, could easily out-accelerate and outclimb all of them while being heavier armed. And flew further with all that.
2. A6m became seriously more vulnerable than its opposition by the second half of 1942 - i.e. it was the result of its development (and especially the development of its contemporaries) and not of the original concept. In the end(1945), it'd obtained just as much or even more armor&survivability measures than most western fighters - it just happened really late, and crippled it more due to the simple lack of engine power and continuing service on the frontlines.
3. For a 1940 fighter, it was decently armed. Then it gradually descended to "average" levels(by ~1943), then in 1944-45 bounced up once again (reaching 3HMG+2 20mm by the end of the war).

Overall A6M is very widely misunderstood as some sort of wrong-designed air display plane. It was not. It just got far behind the curve(hence speed race) due to lack of timely engine replacement.

 

[red admiral]

That sort of make sense, however, if that is the case, then why fighter such as F-15, F-16 emphasized sustained turn rate and acceleration rather than instantaneous turn rate like F-14 and Mirage 2000?. And why TVC wasn't very popular in the West?. If you can't out accelerate missile then the best course of action in WVR combat will be pointing your nose at enemy first

Higher instantaneous turn rate isn't necessarily better. If you're trying to turn through say 180 deg and you do a max rate instantaneous turn then you slow down during the turn and your turn rate varies. You might actually turn through 180 deg in a shorter time period if you simply did a sustained turn.

The engagement might also last more than one cycle (e.g. opposing aircraft also turns rather than extends) in which case you've got more energy for this follow on if you've done a sustained turn. Similar with TVC/post stall. You end up with low energy from this even if you've pointed your nose around very quickly. In which case your wingman steps in...

Fighter Combat: Tactics and Manoeuvring by Shaw goes into a lot of detail on this topic

 

[Justo Miranda]

In World War I, the primary/ priority attribute of fighter is turn rate, better turn rate make better fighters
In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47
In the 1960-1970s, the priority become top speed, acceleration, BVR Ex: F-4
In the 1980-1990s, there is emphasize again on Sustained turn rate, Instantaneous turn rate. Ex: F-16
so what make turn rate important again in the 1980-1990s ? why zoom and boom tactic no longer effective?

Because in the eighties the main enemy was missiles, combats between fighters armed with cannons was not frequent

so boom and zoom was not effective because you can't out accelerate a missile?

To dodge a missile it is necessary to carry out evasion maneuvers and very tight turns

 

[Vanessa1402]

That sort of make sense, however, if that is the case, then why fighter such as F-15, F-16 emphasized sustained turn rate and acceleration rather than instantaneous turn rate like F-14 and Mirage 2000?. And why TVC wasn't very popular in the West?. If you can't out accelerate missile then the best course of action in WVR combat will be pointing your nose at enemy first

Higher instantaneous turn rate isn't necessarily better. If you're trying to turn through say 180 deg and you do a max rate instantaneous turn then you slow down during the turn and your turn rate varies. You might actually turn through 180 deg in a shorter time period if you simply did a sustained turn.

The engagement might also last more than one cycle (e.g. opposing aircraft also turns rather than extends) in which case you've got more energy for this follow on if you've done a sustained turn. Similar with TVC/post stall. You end up with low energy from this even if you've pointed your nose around very quickly. In which case your wingman steps in...

If acceleration no longer important due to the introduction of missile, does that mean fighters that has max STR at lower speed such as F-18, F-14 are much better in visual range combat than energy oriented fighter like F-16 and F-15?

 

[red admiral]

If acceleration no longer important due to the introduction of missile, does that mean fighters that has max STR at lower speed such as F-18, F-14 are much better in visual range combat than energy oriented fighter like F-16 and F-15?

No because the different air vehicle performance parameters are linked. Better acceleration will also mean better rate of climb, better able to regain energy after losing it in doing turns at rates above sustained, likely better sustained turn.

And there's other factors e.g. visibility (from the cockpit and size of aircraft), Field of Regard of the missile seeker etc.

 

[muttly]

Turning at very high speed is hard. Some of the Migs at top speed
can't even turn at all. Speed gets you there to fight and then gets you
out. Maneuvering during the fight I think would be key.

 

[Basher54321]

That sort of make sense, however, if that is the case, then why fighter such as F-15, F-16 emphasized sustained turn rate and acceleration rather than instantaneous turn rate like F-14 and Mirage 2000?. And why TVC wasn't very popular in the West?. If you can't out accelerate missile then the best course of action in WVR combat will be pointing your nose at enemy first

Less important if you have a wingman already pointing at the bad guy.

Most don't realise the F-15 actually has a really good ITR.

Looking at the General Dynamics YF-16 design concepts from the 70s it lists Max speed and STR as being "obsolete" parameters - but ITR and Acceleration as relevant parameters. So the original F-16 concept was very good in all aspects by design - which was in reality mostly based on Vietnam experience and fixing the issues with the F-4 and older lightweight fighters.

Turn performance was only one attribute of the F-4 they fixed but there are more important ones.

The F-16 MATV was seemingly as good if not better than the F-22 at low speed nose pointing but was also cancelled - the cold war ending was one reason. TV adds weight which effects range/endurance and these are more primary attributes to fighters than turn performance. Its use is also limited to situations where a pilot has totally screwed up and TV wont necessarily rectify that. HOBS missiles like AIM-9X also degrade the need to nose point.

Turning has its place but in real world combat through history turning has often been the last thing you would want to do because it makes you more vulnerable - combat has seldom been 1v1.

 

[Vanessa1402]

No because the different air vehicle performance parameters are linked. Better acceleration will also mean better rate of climb, better able to regain energy after losing it in doing turns at rates above sustained, likely better sustained turn

I think if you can't out accelerate a missile then you also can't out climb it, climb are much slower than straight line acceleration
When compare F-14 to F-15 or F-16 , the former has better STR and smaller turn radius, the only advantage of the later is much higher acceleration

 

[steelpillow]

It is basically an issue of changing threats and to some extent changing perceptions.

In WWI, breaking out of a dogfight and diving for safety at high speed was as likely to break up your plane as to escape your pursuer. Low engine powers did not allow for stronger and therefore heavier machines. So fighting scouts were designed above all to out-turn the enemy. Yet in the last year or so of the war, highly manoeuvrable but slow types began to show their vulnerability to their faster and stronger brethren.

In WWII, diving at speed had become a far safer option. Fights took place at higher speeds and encounters were briefer; a single high-speed pass could be safely followed by a high-speed getaway, rather than a fuel-consuming and risky dogfight. The design emphasis shifted accordingly. The need for speed persisted into the subsonic jet era.

The supersonic era changed the game once again. The very high speeds were leading to a change from visually-aimed guns to homing missiles; no more close-in dogfights, just a single pass to launch a missile or two. Also, the main threat was perceived as nuclear bombers, with only a short time to respond. The hot Mach 2.2 interceptor would close with its target at approaching Mach 3, so that single pass needed a lot of avionics to get right. Fighters grew in size, complexity and cost.

So the theory went. But in practice the dogfight refused to go away. Such close combat could only be sustained at subsonic speeds, and that was set by the prevailing air temperature not by aircraft performance. Critical Mach number helped but was a black art, often compromised by other practicalities. Moreover the missile was a lousy weapon for such circumstances; it was by its nature faster than the plane's top speed and consequently less manoeuvrable. A snap shot with a high-rate-of-fire cannon was the thing. Sustained turn rate and cannon armament came back into fashion. Fighters grew even more because they had to be both a missile-armed interceptor and a cannon-armed dogfighter, each carrying the other without loss of capability.

 

[DWG]

In World war II, fighters with better speed and acceleration are better. In short, "boom and zoom" are better than "turn and burn". Turn rate are not important Ex: P-51, P-47

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility. These were a problem for less agile, aircraft if you tried to engage them on equal terms in a manouevring fight. Boom and zoom was a defensive reaction by less agile aircraft, trying to minimise their exposure to the better turn rate of the opposing aircraft, but the vulnerability of the agile aircraft, and generally heavier armament of the fighters forced to engage in boom and zoom, meant that a defensive tactical innovation actually gave them an offensive advantage

so if I understand you corectly, the reason boom and zoom aircraft such as P-51, P-47, FW190 , TA-152 will survive better than turn and burn aircraft such as A6M, Ki-43, Splitfire is mainly due to the fact that they are more heavily armed and heavily armored? (since they don't have to reduce weight? ). Is that a correct?.

It's definitely down to the strengths and weaknesses of both aircraft in the dogfight, not solely one of them. Imagine a dogfight as a series of opportunities to make a mistake. A pilot making his first mistake in a fragile aircraft vs a heavily armed opponent probably won't get a chance for a second try. A pilot making his first mistake in a non-fragile aircraft vs a lightly armed opponent probably will get a second try as the opposing aircraft can't pump out enough damage in the time available.

Weight is deceptive here because you can have a short ranged interceptor optimised for boom and zoom, just as much as a long range heavy fighter.

And I wouldn't really include the Spitfire in the lightly armed and fragile group, it was one of the first 8 gun fighters and had a fully monocoque fuselage, and while it did have a manouevre advantage over the Bf 109, it was a bit lacking against an A6M. It doesn't fall clearly in either class.

<quote>
And the reason boom and zoom doesn't work (or much less effective) on fighter jet, such as F-14, F-15, F-16 is because they are equally lightly armed and equally lightly armored? Is that correct?. Does that make F-14 better than F-16 in WVR combat? because F-14 has superior turn rate why F-16 has superior acceleration
</quote>

I wouldn't use lightly armed or lightly armoured in relation to any modern aircraft. Armour has ceased to be relevant and pretty much everyone is hauling around 4 MRAAMs + 2-4 SRAAMs. Airframes are a platform for moving avionics and missiles around. And the best way the airframe alone can influence the dogfight is by keeping you out of it. Note that avoiding the merge is explicitly a design driver in many modern fighters and that is the reason they have high sustained turn rates.

 

[DWG]

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility.

a6m doesn't fit into this list.

Care to specify how? It was agile, lightly armed, and vulnerable.

"I don't think I have ever flown a fighter that could match the rate of turn of the Zero. The Zero had ruled the roost totally and was the finest fighter in the world until mid-1943."

Captain Eric Brown

1. IJN tactics were ironically energy fight-centric. The ability to do a turn fight doesn't change that fact. Later on, they simply didn't have this choice anymore.
Consequently, A6M wasn't optimized just for agility. It was optimized(put on a diet) for literally everything. Compare it with contemporary(1940-41-42) carrier-borne fighters - it is not just "agile"(a5m was more agile, and biplanes were more agile still). it was faster, could easily out-accelerate and outclimb all of them while being heavier armed. And flew further with all that.
2. A6m became seriously more vulnerable than its opposition by the second half of 1942 - i.e. it was the result of its development (and especially the development of its contemporaries) and not of the original concept. In the end(1945), it'd obtained just as much or even more armor&survivability measures than most western fighters - it just happened really late, and crippled it more due to the simple lack of engine power and continuing service on the frontlines.
3. For a 1940 fighter, it was decently armed. Then it gradually descended to "average" levels(by ~1943), then in 1944-45 bounced up once again (reaching 3HMG+2 20mm by the end of the war).

Overall A6M is very widely misunderstood as some sort of wrong-designed air display plane. It was not. It just got far behind the curve(hence speed race) due to lack of timely engine replacement.

I'm going to differ with your interpretations rather than your facts. Yes, the A6M was long-ranged, but that's a fundamental design driver in carrier aircraft, and ultimately it was more agile than the aircraft it opposed, even if was less agile than the aircraft that preceded it (a point that was generally true, rather than specific to the A6M). And if it was more heavily armed than the A5M, it had very limited ammunition, 60rpg, for its two 20mms and after that it was down to the same two 7.7mms as the A5M, while the Ki-43, in all but the very first production marque, had either one or two 12.7mms. WRT protection it was significantly behind the curve wrt self-sealing tanks from pretty much the onset of the war.

 

[DWG]

So boom and zoom was not effective because you can't out accelerate a missile?

Basically yes. You can extend through the merge but if the other aircraft has sufficient turn rate and rear aspect missiles then its pretty difficult to extend out of missile range in the time its taken the other aircraft to turn through 150-180 degrees. This gets harder with missiles that you can shoot further and further off boresight. And even harder if you've got an all-aspect laser.

That sort of make sense, however, if that is the case, then why fighter such as F-15, F-16 emphasized sustained turn rate and acceleration rather than instantaneous turn rate like F-14 and Mirage 2000?. And why TVC wasn't very popular in the West?. If you can't out accelerate missile then the best course of action in WVR combat will be pointing your nose at enemy first

Sustained turn rate lets you avoid the merge. And with the F-14 you have to remember that it's preferred engagement range is about 60-80nm, everything else is secondary.

As for TVC, its signature manouevres, while spectacular in airshows, leave you in a slow, low-energy state, and while you might use it to outmanouevre the aircraft you're engaged with, that just means its wingman will get you instead.

 

[red admiral]

I think if you can't out accelerate a missile then you also can't out climb it, climb are much slower than straight line acceleration
When compare F-14 to F-15 or F-16 , the former has better STR and smaller turn radius, the only advantage of the later is much higher acceleration

You're not out manoeuvring the missile, you're managing your energy across multiple engagement cycles in order to finally get in a position for a good shot with your own missiles or guns. E.g. one aircraft does a max rate turn to get it's nose round quickly and bleeds off loads of energy whereas the other aircraft goes into the vertical and maintains energy swapping speed for altitude. If the first one doesn't get a good shot in the first turn it's in a far worse position for the next cycle. Or far more vulnerable to the second aircraft's wingman.

In general today within visual range combat is very lethal to both parties

 

[Colonial-Marine]

The F-17, originating from the same requirement, had similar weaknesses, but benefitted from being reworked into the F-18 to add carrier capability, and still needed a second generation, and then a growth version, and still doesn't meet some of the F-18's design requirements.

What original requirement do current versions of the F/A-18 not meet?

 

[DWG]

The F-17, originating from the same requirement, had similar weaknesses, but benefitted from being reworked into the F-18 to add carrier capability, and still needed a second generation, and then a growth version, and still doesn't meet some of the F-18's design requirements.

What original requirement do current versions of the F/A-18 not meet?

Range, AIUI.

 

[Vanessa1402]

So boom and zoom was not effective because you can't out accelerate a missile?

Basically yes. You can extend through the merge but if the other aircraft has sufficient turn rate and rear aspect missiles then its pretty difficult to extend out of missile range in the time its taken the other aircraft to turn through 150-180 degrees. This gets harder with missiles that you can shoot further and further off boresight. And even harder if you've got an all-aspect laser.

That sort of make sense, however, if that is the case, then why fighter such as F-15, F-16 emphasized sustained turn rate and acceleration rather than instantaneous turn rate like F-14 and Mirage 2000?. And why TVC wasn't very popular in the West?. If you can't out accelerate missile then the best course of action in WVR combat will be pointing your nose at enemy first

Sustained turn rate lets you avoid the merge.

Didn't F-16 lack the BVR capability until much later block? early production block of F-16 can't carry and launch AIM-7 so it must enter the merged , however it still emphasize sustain turn rate above all else

 

[steelpillow]

At the onset of WWII you had a generation of aircraft heavily optimised for agility - Cr.32, Cr.42, A5M, A6M, Ki 43. They also tended to be lightly armed and fragile because weight is a problem if you want to optimise agility. These were a problem for less agile, aircraft if you tried to engage them on equal terms in a manouevring fight. Boom and zoom was a defensive reaction by less agile aircraft, trying to minimise their exposure to the better turn rate of the opposing aircraft, but the vulnerability of the agile aircraft, and generally heavier armament of the fighters forced to engage in boom and zoom, meant that a defensive tactical innovation actually gave them an offensive advantage

so if I understand you corectly, the reason boom and zoom aircraft such as P-51, P-47, FW190 , TA-152 will survive better than turn and burn aircraft such as A6M, Ki-43, Splitfire is mainly due to the fact that they are more heavily armed and heavily armored? (since they don't have to reduce weight? ). Is that a correct?.

I'd suggest it was more a consequence of engine development and response to circumstance. Given a more powerful engine for your next fighter, how are you going to optimise it against the current generation of manoeuvrable but vulnerable and underarmed slowcoaches? The extra engine power means that you can deliver more: 1. speed, 2. armour, 3. firepower. Anything else? Well, the higher speeds make for wider turning circles and the extra firepower needs less time pointing at the target, so go for boom-and-zoom tactics, that should work.
If you follow the history of the Spitfire through the war, that was exactly what happened from mark to mark to mark: from normally-aspirated Merlin, .303" (7.7 mm) bullets and modest armour to two-stage supercharged Merlins and Griffons, 20 mm (.787") cannon shells and much strengthened airframe all round. Tactics adapted to the planes and their adversaries, not the other way round.

It was different during the jet age, as development times of each generation ran into decades. Each had to represent a major step forward in technology and many lessons of the past would no longer apply. You had to plan your battle tactics and associated performance characteristics in advance, build the planes around them, and then avoid swearing too loudly when you found that some of those old lessons were still valid after all.

 

[BB1984]

It's a big topic, but a couple thoughts:

• WWI is an outlier for a few reasons. The limitations of the aircraft have already been brought up. Also remember that air combat was brand new and was being developed on the fly (pardon the pun). Dicta Boelcke was revolutionary at the time, but now seems like things you could pick up from any fighter combat movie of the last 50-60 years.
  
  
• From the inception of Air to Air combat through the AIM-9H level of AAM development, so up till 1975 or so, the fundamental for winning air to air combat was getting behind your enemy. Directly behind and closer was best, even with the IR AAM at the end of the era. During this period, Boyd's theories applied because pilots had to maneuver to get into firing position.
  • Yes BVR was becoming feasible late in this period but the missiles had low hit probability and even when success was achieved, it was never done in mass fighter combat or against an enemy with significant ECM capabilities, so yes missiles like the AIM-7 Sparrow were having an impact, but they were a secondary weapon.

• After 1975, all aspect and off-boresight AAM started to come into play and, at the same time, BVR missiles were maturing. These two developments, both on-going, have been progressively decreasing the importance getting behind, or even within sight of, an enemy and this is leading to a sea change in tactics and, with that, major changes in what is important for a fighter. Arguably the biggest change is the decreased importance of sustained turn capability, but some things, like thrust to weight, are big in both eras.
  
  
• IMHO, there are two under-discussed aspects of energy combat (vs. turning combat)
  • The first is that a fighter with greater speed/altitude (both of which translate into energy) has the initiative and can choose when combat starts and ends. An opponent without this initiative, but with superior turning ability, tries to turn the battle into a turning fight at slower speeds because it is the only option available. This was the position of many Japanese flying against the Americans in '43-'45 and also of the North Vietnamese in Mig-17s vs. the US thirty or so years later.
  • The second is that energy tactics require a much higher level of training. Turning combat, and "follow the leader" maneuvering is simple and intuitive. Compare this to even the relatively simple High Yo-Yo or Lag displacement roll tactics which are not intuitive at all. Energy tactics will not be used, or only be used in their simplest version (i.e., boom and zoom) unless the pilots are not only well trained, but well trained in air to air combat. I believe this is why the only combat you see in movies is turning style combat: it's maneuvers that the audience can understand without any training.

 

[CV12Hornet]

With the Teen series there's also the effect of technological improvements making some of the compromises of previous jet fighters less necessary. See, speed and maneuverability are, in the jet era, in large part diametrically opposed. The reason is that speed is a function of thrust and drag, while maneuverability is a function of weight and lift*. And the biggest source of drag in any aircraft design is the wing. This is why a lot of early supersonic aircraft tended to have small wings (the F-104 in particular), and consequently poor maneuverability: to minimize drag, particularly in the supersonic regimes.

With the powerful turbofan engines of the 1970s onward, this all-out need to reduce drag was not as necessary. More thrust meant designs could overcome more drag than previous designs, which led to much larger wings - the F-15 has a significantly larger wing than the F-4 Phantom but weighs about the same in most combat situations.

There were also aerodynamic advances as well. Lift body fuselages improved lift without excessive drag, and this was around the time aircraft designers were really starting to take advantage of vortex generation to enhance maneuverability - it's why European fighter designs tended towards delta wings. And of course the relaxed top speed requirements for many fighters certainly helped.

The result was that you could build a fighter that was both very fast and very maneuverable, whereas before you had to pick one or the other. The crowning example, of course, being the Eagle.

* This is a major oversimplification but it'll do for this.

 

[DWG]

Sustained turn rate lets you avoid the merge.

Didn't F-16 lack the BVR capability until much later block? early production block of F-16 can't carry and launch AIM-7 so it must enter the merged , however it still emphasize sustain turn rate above all else

You can't try to apply these general points without also considering the wider design context for each individual aircraft. F-16 in particular is an anomaly, built to the requirements of a man who wanted a fighter to outdogfight MiG-15s over Korea and MiG-19s over Vietnam, where the circumstances favoured sustained rate because that let you turn inside MiGs in a wagonwheel/lufbery circle.

 

[BB1984]

And the biggest source of drag in any aircraft design is the wing. This is why a lot of early supersonic aircraft tended to have small wings (the F-104 in particular), and consequently poor maneuverability: to minimize drag, particularly in the supersonic regimes.

This is where energy comes in: the F-104 had poor maneuverability in a purely horizontal fight but it had very good maneuverability overall. High Yo-Yo, Lag displacement roll, and Barrel Roll attack are all maneuvers that use vertical movement in a turning fight, i.e., they use an energy approach instead of relying on sustained turn rate.

The US Tactical Air Command (TAC) conducted the Featherduster trials of dissimilar aircraft in WVR dogfights. TAC's F-100C/D/F, F-4C, F-105D and F-104C were tested against both each other and against dissimilar opponents including the F-102A and F-106A (stand-ins for the MiG-21), F-86H (MiG-17), and F-8C/D (MiG-19). The F-104 came out as the best dogfighter, doing very well against all opponents as long as the F-104 pilots didn't get into a turning (i.e., a horizontal) fight, particularly with the F-8s.

The later F-15/F-16 programs were a "have your cake and eat it too" solution where advanced engines and aerodynamics allowed planes to have both excellent horizontal and vertical maneuverability. They were both conceived and designed before all aspect and off-boresight AAM were in production and before BVR missile technology had demonstrated serious combat potential, i.e., when energy maneuver was still the best approach. One could argue that they should have looked ahead to future missile development and possibly taken a modified approach, but OTOH missile engineers had over-promised and under-delivered for decades so maybe that's forgivable.

 

[Desertfox]

Its quite interesting that when the USAF finally got the issues with AAM worked out then went with the fighter with superior WVR performance in the F-22 over the one with superior BVR performance in the YF-23. You could say the final victim of Boyd was the YF-23.

 

[red admiral]

The US Tactical Air Command (TAC) conducted the Featherduster trials of dissimilar aircraft in WVR dogfights. TAC's F-100C/D/F, F-4C, F-105D and F-104C were tested against both each other and against dissimilar opponents including the F-102A and F-106A (stand-ins for the MiG-21), F-86H (MiG-17), and F-8C/D (MiG-19). The F-104 came out as the best dogfighter, doing very well against all opponents as long as the F-104 pilots didn't get into a turning (i.e., a horizontal) fight, particularly with the F-8s.

Thanks for that

Pretty interesting reading that trial. Very much dependent on the timeframe - i.e. primary guns with very early rear aspect only IR missiles.

F-104 tactics quite interesting. Use speed / Accel to extend out of guns/missile range, make opposition lose visuals and then effectively reset the engagement on your own terms. Stay very fast and maintain energy until you get a good shot opportunity yourself.

It nicely brings out some other points e.g. small size of F-104 makes keeping track of it difficult.

And with technology changes then tactics change e.g. more all aspect missiles make it really hard to extend and escape

 

[Deleted member 2278]

F-104s? Manoeuvring? Snake Sez.......

snake sez f-104 - Google Search

 

[Basher54321]

Its quite interesting that when the USAF finally got the issues with AAM worked out then went with the fighter with superior WVR performance in the F-22 over the one with superior BVR performance in the YF-23. You could say the final victim of Boyd was the YF-23.

Was well after Boyds time.

USAF Chief engineer on the project (Eric Able) was well aware that the USAF seldom gets the final say on what fighter actually ends up getting bought so ensured both YF-23 and YF-22 met the USAF requirements.
That way it didnt matter who chose the aircraft because both were more than good enough for what was wanted.

 

[Basher54321]

The later F-15/F-16 programs were a "have your cake and eat it too" solution where advanced engines and aerodynamics allowed planes to have both excellent horizontal and vertical maneuverability. They were both conceived and designed before all aspect and off-boresight AAM were in production and before BVR missile technology had demonstrated serious combat potential, i.e., when energy maneuver was still the best approach. One could argue that they should have looked ahead to future missile development and possibly taken a modified approach, but OTOH missile engineers had over-promised and under-delivered for decades so maybe that's forgivable.

Absolutely and Boyds experience in the 50s and 60s was of technology that was demonstrably junk without exception. The radars were almost dead weight and combat was in reality a 99% pure visual affair. There is no point looking back 50 years later and saying but why didn't they see the digital revolution coming etc - pointless because at the time they had a valid point.


Contrary to what was written above for the LWF, Boyd was only part of a team as far as the requirements goes and was in no position to dictate anything. That is one reason why the 1971 LWF requirements were for an all weather in any light conditions fighter - even Boyd eventually agreed the radar was a good thing.

It also wasn't Boyd that went out of their way to keep AIM-7 off the F-16A.

A main driver was cost - lower cost = higher numbers and sortie rate. It was also designed to be easy to maintain with a quick turnaround time. Also that cost is probably also only going to buy you an F-16 / Mirage sized airframe at the end of the day.