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Faro
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Swing Wings: How Did They Die Off?

Fri Feb 16, 2018 10:09 am

There was a brief period in the mid-1960's to mid-1970's when swing wings were hugely popular in new combat aircraft desings...by the 1980's this massive trend was dead and buried.

What happened and why?


Faro
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mmo
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Re: Swing Wings: How Did They Die Off?

Fri Feb 16, 2018 10:36 am

Several things from a US perspective.

First of all, the swing wing mechanism was extremely heavy and the additional weight was an issue. One reason the F-111B never materialized for the USN. Secondly, there was a move away from "one size fits all" aircraft to more specialized aircraft. USAF has A-10, F-15 and F-16. While you could argue the F-16 was more a "do all" aircraft, it didn't start out that way. Finally, more refined wing design, better power plants and FBW.
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Ozair
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Re: Swing Wings: How Did They Die Off?

Fri Feb 16, 2018 11:25 am

mmo wrote:
Several things from a US perspective.

First of all, the swing wing mechanism was extremely heavy and the additional weight was an issue. One reason the F-111B never materialized for the USN. Secondly, there was a move away from "one size fits all" aircraft to more specialized aircraft. USAF has A-10, F-15 and F-16. While you could argue the F-16 was more a "do all" aircraft, it didn't start out that way. Finally, more refined wing design, better power plants and FBW.

I'd add that wing design moved towards deltas as found on most european jets and on the F-22/35. A delta wing has good performance across multiple speeds and altitudes, typically has a large wing area, is reasonably easy to maintain and comparatively light compared to a swing wing.
 
ThePointblank
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Re: Swing Wings: How Did They Die Off?

Fri Feb 16, 2018 11:27 am

Too much weight, too much complexity, and too maintenance intensive. Look up the Cold Proof testing procedure for the F-111 for starters, and the F-14's issues with the hydraulic wing sweep mechanism.

Also, managing the RCS for an aircraft that can swing its wings is a nightmare. Not to mention the lost space inside the aircraft where one can put larger fuel tanks in for more range. Fly By Wire systems also expedited the killing off of variable swept wings; the reason variable wing is utilized in an aircraft design is to make it perform well on different flight envelopes, mainly slow speed and high speed handling. Swept wing is good for high speed work but perform poorly at low speeds and vice versa.

Digital FBW systems however fixes that. You can tell the computer to manage how the aircraft handles in all flight regimes, and it will do that for you regardless of the wing shape. For example, the Mirage 2000 with it's FBW systems can very comfortably fly low speed, high AoA, when delta wing aircraft were not well known for that sort of capability.

Digital FBW can do more than that though. Since it's effectively the computer flying the airplane you can design the aircraft with relaxed stability, which would be very hard or outright impossible for a human pilot to fly.
 
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Re: Swing Wings: How Did They Die Off?

Fri Feb 16, 2018 12:27 pm

In addition to what was written above, don't forget that while swing wing is looking very good on paper, it's not simple to maintain. Also, if it sustains battle damage, you have an additional variable or failure point. Imagine, what it is like for a pilot, struggling to control his damaged plane, to find out that he also has asymmetric wing position to contend with.
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Re: Swing Wings: How Did They Die Off?

Fri Feb 16, 2018 12:43 pm

Several things happened:

Fly-by-Wire and relaxed stability meant that fighters could achieve high turn rates and good nose-pointing capablities with regular delta (Eurofighter, Gripen) or trapezoid wings (F-22, F-35).
Better nose-pointing ability also means lower wing loading, for which the delta wing is pretty good. Early delta wings had the issue of extreme stability at high speeds. The Mirage was almost unable to turn while supersonic. Relaxed stability and canards solved that problem.

Less need for speed, particularly for high-speed low-level penetration flights. The B1, F-111 and Tornado were or are among the fastest aircraft on the deck. Most modern fighters need to get up to altitude to reach their top speeds and even then, few reach the top speeds of some older jets. Instead, they can supercruise for an extended time.

Edit: Let me emphasize this point by quoting two stackexchange comments:

Swing wings combine the high sweep angle helpful for Mach 2+ flight with tolerable low-speed handling characteristics. They were needed to fulfil the demands on military aircraft called for in tenders before planners realized in the late Sixties that high speed was not needed.

When flying at supersonic speed, it helps if the sweep angle of the wing's leading edge is higher than the Mach cone angle. Since the Mach angle goes up with the arcsine of the Mach number, this requires more than 60° of sweep at Mach 2 and 70.5° at Mach 3. If the sweep angle of the leading edge is higher, the flow around it will still be similar to that of subsonic flow around a straight leading edge. This leaves effects like the suction peak near the leading edge in place which would disappear once the flow component perpendicular to the leading edge becomes supersonic. A subsonic leading edge greatly lowers drag at supersonic speed.


When those supersonic-capable aircraft were used in real conflicts, something very surprising and unforeseen happened: They did hardly ever fly supersonic. When the Air Force in the late Sixties accumulated the flight data from several years of Vietnam war air combat, they found that all aircraft had accumulated just minutes at Mach 1.4 and only seconds at Mach 1.6 out of more than 100,000 combat sorties¹. Never was even Mach 1.8 flown in aircraft which had been optimized for Mach 2.4 (F-104, F-105, F-106A, F-4D/E and F-111). [...]
Even for flying into the combat arena supersonic speed was rarely advantageous. Northrop studied a multitude of intercept cases and found that speeds above Mach 1.1 were almost never helpful because they curtailed the combat radius severely. [...] Building into [their designs] the capacity for Mach 2+ made them worse for what they were actually used for.
From the late Sixties on this lesson was incorporated into the newer designs like the F-16. Stealth again decreased the importance of supersonic capability, and the maximum sustained speed of the F-22 was actually reduced from Mach 1.8 to Mach 1.6 to reduce the heat load on the composite wing leading edge.


Stronger engines mitigated the need for optimised take-off and approach configurations. The F/A-18 has a ~10 % better T/W ratio than the F-14. It also has half the empty weight despite similar loadouts. Particularly the delta wing is a great performer at low speeds, it just creates an incredible amount of drag. Once that is no longer an issue, the need for a low-sweep configuration vanishes. Interestingly, delta wings do not stall in the sense traditional wings do. Advances in aerodynamics also helped simplify landing flaps, The A320 & A380 for example only need 1 flap versus the 737's & 747's 3.


TLDR: Swing wings add weight in exchange for the capability to fly very fast and very slow. New fixed wings and their aircraft became better at handling all speeds up to Mach 1.6 while requirements for speeds greater than Mach 1.6 disappeared.
 
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Faro
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Re: Swing Wings: How Did They Die Off?

Sat Feb 17, 2018 10:20 am

ThePointblank wrote:
Too much weight, too much complexity, and too maintenance intensive. Look up the Cold Proof testing procedure for the F-111 for starters, and the F-14's issues with the hydraulic wing sweep mechanism.

Also, managing the RCS for an aircraft that can swing its wings is a nightmare. Not to mention the lost space inside the aircraft where one can put larger fuel tanks in for more range. Fly By Wire systems also expedited the killing off of variable swept wings; the reason variable wing is utilized in an aircraft design is to make it perform well on different flight envelopes, mainly slow speed and high speed handling. Swept wing is good for high speed work but perform poorly at low speeds and vice versa.

Digital FBW systems however fixes that. You can tell the computer to manage how the aircraft handles in all flight regimes, and it will do that for you regardless of the wing shape. For example, the Mirage 2000 with it's FBW systems can very comfortably fly low speed, high AoA, when delta wing aircraft were not well known for that sort of capability.

Digital FBW can do more than that though. Since it's effectively the computer flying the airplane you can design the aircraft with relaxed stability, which would be very hard or outright impossible for a human pilot to fly.




I agree re weight, complexity and maintenance but those were all known items at the time of design. It was expected that the F-111 for example would be heavier, more complex and maintenance-intensive than classic-winged fighters. These unfavourable items were consented to as part of the overall design package for two reasons: i) enhanced manoeuvrability and handling at low speeds and greatly reduced drag in the trans-sonic/supersonic regimes. In the following video (at 10:00), the F-111 --wings fully swept back-- is quoted as having less total drag at Mach 1.2 than the F-4, a very much smaller and lighter design.

https://www.youtube.com/watch?v=A-hrrMlksNA

It is no coincidence that the F-111 had around 2,500nm ferry range on internal fuel only which is unheard of for a fighter. IMHO weight, complexity and maintenance in and of themselves were not what materially invalidated swing-wing designs over time because they were not totally unknown, surprise design issues.

RCS is definitely a consideration, yes. Yet with the passing, then-classified and obscure exception of the D-21, RCS was not a significant factor in combat aircraft design before perhaps the B-1B. I would submit that RCS reduction was very much a late 1970's phenomenon.

The matter of lost internal space and sacrificed fule capacity is valid but can and was mitigated (in any case with the F-111 as mentioned above) albeit at the expense of heavier, more cumbersome design weights.

FBW is a peculiar issue: the F-111 already incorporated a primitive FBW of a sort. Control stick deflection did not command control surface deflection but rather a given level of G/roll rate (refer above video at 06:15). That being said, modern FBW does indeed enhance handling and manoeuvrability in all flight regimes. What it does not do however is significantly reduce trans-sonic/supersonic drag like a swing-wing would.

IMHO opinion the reason why swing-wings went out of favour perhaps has more to do with the reduced emphasis on high supersonic speed capability as mentioned by mxaxai in his # 6 above post...along with the gradual realisation that the tailed-delta configuration (pioneered for supersonic flight by the MIG-21) is the single most optimal design for supersonic fighter aircraft. Variations of this basic configuration can be found on a whole range of modern combat aircraft from the F-15 to the F-16 to the F-22 (all cropped deltas) to the MIG-29 (slightly swept, cropped delta) and Su-57 (compound delta). Quite a momentous shift when one considers that initially, all designs submitted for the USAF's F-X competition in the late 1960's were swing-wings...


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Re: Swing Wings: How Did They Die Off?

Sat Feb 17, 2018 12:30 pm

Faro wrote:
RCS is definitely a consideration, yes. Yet with the passing, then-classified and obscure exception of the D-21, RCS was not a significant factor in combat aircraft design before perhaps the B-1B. I would submit that RCS reduction was very much a late 1970's phenomenon.[Faro


I think you might want to do some research on the SR-71 and the A-12. Both designs were heavily influenced by the drive to minimize RCS.
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Re: Swing Wings: How Did They Die Off?

Sat Feb 17, 2018 5:10 pm

mmo wrote:
I think you might want to do some research on the SR-71 and the A-12. Both designs were heavily influenced by the drive to minimize RCS.


https://www.cia.gov/library/center-for- ... 2Feb12.pdf
interesting read.
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Re: Swing Wings: How Did They Die Off?

Sat Feb 17, 2018 8:59 pm

Up until and including the F-15, the USAF seemed obsessed with speed. The boundary kept getting pushed further and further. Speed was the Holy Grail. One of the best ways to achieve this while still retaining good low speed handling was with the swing wing. The USN also wanted top speed but had the added challenge of having to land that fast aircraft on a moving ship and not having the luxury of the 2 mile long runways that the USAF enjoyed, which led to the F-14 with its swing wing. Also on the 2 books I just read about our 'secret' MiG squadrons out at Tonopah here in the US all of our pilots were very impressed by the MiG-23 if for nothing else than its speed, nothing could accelerate with it or match it on the deck. Same for our F-111. But alas all good things come to an end and the fascination with having the fastest aircraft was not the focus anymore, as pointed out above those top speeds were almost never seen, used or needed. So then the previously ever rising speed graph that climbed from the subsonic F-84/86/89/94 rose steadily thru the F-100 and Century series and later culminated in those Mach 2.5'ish F-14/15/111 and then started the gradual decline that it is now.
 
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Re: Swing Wings: How Did They Die Off?

Sun Feb 18, 2018 8:36 pm

The F-111 probably has great ferry range (subsonic) because it needed to have useful range at Mach 2.5, no ?

No mention of SAMs ? By the end of the 60's missiles could fly faster than any aircraft, making that speed useless. Hence why the F-111 was used down low when it was clearly made to fly high and fast.
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Re: Swing Wings: How Did They Die Off?

Sun Feb 18, 2018 9:40 pm

Aesma wrote:
The F-111 probably has great ferry range (subsonic) because it needed to have useful range at Mach 2.5, no ?

No mention of SAMs ? By the end of the 60's missiles could fly faster than any aircraft, making that speed useless. Hence why the F-111 was used down low when it was clearly made to fly high and fast.


The F-111 was made as a long range, low level penetration fighter bomber or with the FB-111, bomber. It would have been nothing more than SAM bait up high. I am somewhat confused as to where you got the idea it was made to fly high and fast.
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Ozair
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Re: Swing Wings: How Did They Die Off?

Sun Feb 18, 2018 11:16 pm

mmo wrote:
The F-111 was made as a long range, low level penetration fighter bomber or with the FB-111, bomber. It would have been nothing more than SAM bait up high. I am somewhat confused as to where you got the idea it was made to fly high and fast.

Given one of the original roles of the F-111 for the USN, in the form of the B variant, was going to be a long range interceptor a high speed and long range was likely a key requirement.
 
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 12:54 am

I imagine most of the reasons for the demise of the swing wing have been covered above but Haveblue touched on something which does not often get discussed and that is what has been lost with its passing;

Real low level speed/penetration ability.

The F-111, F-14, Tornado, Might 23, B-1 all possessed​ the ability to sustain high speed at low level that is unmatched by any modern fixed wing design. I'd have to go back and research what were the exact aerodynamic qualities that were unique to the swingers that gave them the advantage in ride quality that enabled them to sustain low level speed but it is a regime they all excelled at. I assume it is the drive towards low wing loading of air superiority fighters that makes the delta/ tailed delta inferior in that regime. I know the F-15 has the raw power on paper but I believe it couldn't really do it like the swingers.

I know that advances​ in SAMs and IADS's have made the survivability of low level penetration unacceptable and all aspect stealth is the current panacea but here's a thought?

Suppose someone cracks stealth, or through neural networking manages to consistently combine sensors sufficiently to direct an IR SAM to the right patch of airspace and the survivability of mid level is compromised? What then for interdiction?

In the same way you can't jam a bullet, a true low level interdictor will always be difficult to stop.

The only option for interdiction will be back down on the deck. I doubt any of the canards (EF, Rafale, Gripen) are too effective at low level due to wing loading. Similarly PakFa and the Chinese stealth fighters in development look like they're all wing and unlikely to be good in the weeds.

Does anyone know how the F-35 is likely to perform if forced down low?
 
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 1:05 am

ThePointblank wrote:
Too much weight, too much complexity, and too maintenance intensive. Look up the Cold Proof testing procedure for the F-111 for starters, and the F-14's issues with the hydraulic wing sweep mechanism.

Also, managing the RCS for an aircraft that can swing its wings is a nightmare. Not to mention the lost space inside the aircraft where one can put larger fuel tanks in for more range. Fly By Wire systems also expedited the killing off of variable swept wings; the reason variable wing is utilized in an aircraft design is to make it perform well on different flight envelopes, mainly slow speed and high speed handling. Swept wing is good for high speed work but perform poorly at low speeds and vice versa.

Digital FBW systems however fixes that. You can tell the computer to manage how the aircraft handles in all flight regimes, and it will do that for you regardless of the wing shape. For example, the Mirage 2000 with it's FBW systems can very comfortably fly low speed, high AoA, when delta wing aircraft were not well known for that sort of capability.

Digital FBW can do more than that though. Since it's effectively the computer flying the airplane you can design the aircraft with relaxed stability, which would be very hard or outright impossible for a human pilot to fly.


Not to mention the D6AC material the WCTB was made out of!

Nowadays, this extreme high speed low level flight just isn't needed, the sort of thing the F111, TSR.2**, swing-wing MIG aircraft, swing-wing Mirage designs and others were designed for can be brought undone by look down radars. The name of the game now is either fly in a very stealthy aircraft or go like a bat out of hell at 120,000+ft, ie, so fast that nothing can do anything about it. Or you use drone-swarms. I think the option of drone-swarms is the best one.
------
**On the note of the TSR.2, I wonder exactly how fast it would have gone had it not only done just one flight in the transonic region (the final test flight before cancellation). "Bee" who was at the controls of it apparently ran away from an English Electric Lightning chase aircraft with just one engine in afterburner, and the Lightning was on full power. :eyepopping: TSR.2 Also did have a hybrid fly-by-wire system. I won't go too much further on this subject because it's a sore point for many people (and still controversial).

Edit 2: A near 36 ton aircraft with installed power of 60,000lb thrust?! Absolutely insane.
 
Ozair
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 2:34 am

spudh wrote:
Real low level speed/penetration ability.
In the same way you can't jam a bullet, a true low level interdictor will always be difficult to stop.

I think low level will always remain more dangerous than mid or high. Looking back at the threat environment, Vietnam remains a consistent and documented case, AAA and low level SAMs remained the most challenging threat environment and where aircraft were most likely to be engaged and impacted.

spudh wrote:
The only option for interdiction will be back down on the deck. I doubt any of the canards (EF, Rafale, Gripen) are too effective at low level due to wing loading. Similarly PakFa and the Chinese stealth fighters in development look like they're all wing and unlikely to be good in the weeds.

Does anyone know how the F-35 is likely to perform if forced down low?

While I hate to give answers based on such little information, in simplistic terms higher wing loading provides a better ride at low level than low winging. It is hard to compare modern fighter aircraft given the large amount of body lift generated and how much wing loading is impacted by fuel and ordnance load.

There are some basic calculations here, http://www.f-16.net/forum/viewtopic.php?f=36&t=24962 which include typical weights and loadouts (AA load out though...) and see the F-35 being higher than the Eurocanards and similar to the F-16/F-18/Su-35.
 
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 6:07 am

Ozair wrote:
mmo wrote:
The F-111 was made as a long range, low level penetration fighter bomber or with the FB-111, bomber. It would have been nothing more than SAM bait up high. I am somewhat confused as to where you got the idea it was made to fly high and fast.

Given one of the original roles of the F-111 for the USN, in the form of the B variant, was going to be a long range interceptor a high speed and long range was likely a key requirement.


So, how did that work out?

I can tell you a low level environment will always be a much better place for a fast mover. Just the whole issue of radar tracking, and the ability to lock on is complicated when you are flying low level. If done properly, with terrain masking it is tough to get a lock on long enough to allow a firing solution. If you look at the F-111 operations in SE Asia, other than CFIT, the Aardvark did pretty well down low. The F-4, F-105, A-4 and A-7 all had a tough time at medium to high altitudes with the SA-2.
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 6:26 am

Aesma wrote:
The F-111 probably has great ferry range (subsonic) because it needed to have useful range at Mach 2.5, no ?

No mention of SAMs ? By the end of the 60's missiles could fly faster than any aircraft, making that speed useless.


In a tail chase a Mach 2.5 aircraft has quite a better chance vs. a SAM than at Mach 2 or slower.

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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 6:34 am

mmo wrote:
Ozair wrote:
mmo wrote:
The F-111 was made as a long range, low level penetration fighter bomber or with the FB-111, bomber. It would have been nothing more than SAM bait up high. I am somewhat confused as to where you got the idea it was made to fly high and fast.

Given one of the original roles of the F-111 for the USN, in the form of the B variant, was going to be a long range interceptor a high speed and long range was likely a key requirement.


So, how did that work out?

I can tell you a low level environment will always be a much better place for a fast mover. Just the whole issue of radar tracking, and the ability to lock on is complicated when you are flying low level. If done properly, with terrain masking it is tough to get a lock on long enough to allow a firing solution. If you look at the F-111 operations in SE Asia, other than CFIT, the Aardvark did pretty well down low. The F-4, F-105, A-4 and A-7 all had a tough time at medium to high altitudes with the SA-2.


But SE Asia was 50 years ago, the technology now is quantum leaps from the 60's and early 70's for detection and counter measures, well everything really.

What is needed is a high speed, low level, no heat signature, high payload, long range, multi role stealth aircraft. Did I miss anything ?
 
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 9:01 am

tommy1808 wrote:
Aesma wrote:
The F-111 probably has great ferry range (subsonic) because it needed to have useful range at Mach 2.5, no ?

No mention of SAMs ? By the end of the 60's missiles could fly faster than any aircraft, making that speed useless.


In a tail chase a Mach 2.5 aircraft has quite a better chance vs. a SAM than at Mach 2 or slower.

best regards
Thomas


The kinds of missiles out there could make life difficult for even the SR-71. Even something like a B-70 wouldn't have been safe, even at Mach 3.0. A TSR.2 at high speed and high altitude probably would also have been very vulnerable, hence why it (and others of the same type) were designed to go really quick at very low altitude and follow the terrain.

The only thing safe from those missiles might have been those boost-glide recon aircraft that were actively being researched and developed in the 60s. But those aircraft in reality were not much more useful or flexible than a satellite. Goes up quickly, does one pass at high speed then glides back down. If any of the ones under development did get into service, they certainly kept the operations quiet or otherwise they weren't successful.
 
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 9:36 am

cpd wrote:
tommy1808 wrote:
Aesma wrote:
The F-111 probably has great ferry range (subsonic) because it needed to have useful range at Mach 2.5, no ?

No mention of SAMs ? By the end of the 60's missiles could fly faster than any aircraft, making that speed useless.


In a tail chase a Mach 2.5 aircraft has quite a better chance vs. a SAM than at Mach 2 or slower.

best regards
Thomas


The kinds of missiles out there could make life difficult for even the SR-71. Even something like a B-70 wouldn't have been safe, even at Mach 3.0. .


I didn´t say "safe", just "safer". More speed means less reaction time and less range in a tail chase. Hight and fast enough almost every engagement ends up in a tail chase. Even the good ol SA-2 could have shot down an SR-71, but the command and control to get them up in the air in time to make the intercept was somewhat difficult.

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Ozair
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 9:38 am

mmo wrote:

So, how did that work out?

I never said it was a good idea, what I said was the original requirements that formed the specifications of the F-111 clearly stated high speed and dash capability, including both USAF and USN variants.

mmo wrote:
I can tell you a low level environment will always be a much better place for a fast mover. Just the whole issue of radar tracking, and the ability to lock on is complicated when you are flying low level. If done properly, with terrain masking it is tough to get a lock on long enough to allow a firing solution.

I disagree, the low level threat environment is decidedly more hazardous to aircraft, GW1 clearly taught us this. Were the USAF to go to war in North Korea today, the AAA threat would almost certainly down more aircraft than SAMs.

mmo wrote:
If you look at the F-111 operations in SE Asia, other than CFIT, the Aardvark did pretty well down low. The F-4, F-105, A-4 and A-7 all had a tough time at medium to high altitudes with the SA-2.

Hold on, we don't need to go and make claims when we have some great stats on Vietnam available here, http://www.dtic.mil/dtic/tr/fulltext/u2/c016682.pdf

There are a multitude of tables in that source doc that clearly indicate the threat with ground fire not including SAMs comprising the overwhelming contribution to the loss rate of aircraft in Vietnam, even over North Vietnam. The F-111 had so few missions, 8845 sorties, compared to the F-4, 496670 sorties, and F-105, 159795 sorties that the statistics for the F-111 are not representative of true loss rates.

We can see that the SA-2 played a larger role in loss rates during the later years of Vietnam 71-73 compared to earlier but non SAM ground fire was still the predominant threat and resulted in more losses.

jupiter2 wrote:

But SE Asia was 50 years ago, the technology now is quantum leaps from the 60's and early 70's for detection and counter measures, well everything really.

Vietnam is still a valid scenario to examine threats to aircraft from surface based weapons. While technology has moved on, especially in the area of precision guided weapons and targeting systems, the threat and counter threat systems are broadly similar to what was available then. GW1 also proved that the low level threat environment still exists and why the USAF and most other western nations now employ medium level bombing as their primary delivery method.
 
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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 10:24 am

I wonder what with low-observable, stealthy radar as installed on the F-22, F-35 and other 5th generation fighters...are we not back to the era of pure BVR air-to-air engagements as prematurely posited in the 1950's?...if you are stealthy and cannot be detected, and can use your radar in long-range microbursts to detect enemy aircraft and launch air-to-air and air-to-ground weapons while remaining yourself undetected...then low-level high-speed penetration, dogfighting and cannon fire may perhaps become obsolete...

In the long-term, grand scheme of things, perhaps Vietnam will prove to have been a false positive...


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Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 10:46 am

jupiter2 wrote:

But SE Asia was 50 years ago, the technology now is quantum leaps from the 60's and early 70's for detection and counter measures, well everything really.

What is needed is a high speed, low level, no heat signature, high payload, long range, multi role stealth aircraft. Did I miss anything ?


Where to start on this reply and the others which followed.

First of all you posters are looking at a F-111 in today's threat environment. The reason the Aardvark/Sparkvark were put out to pasture was the cost to get the engine and avionics up to the threat and upcoming threat. They went to a follow on aircraft.

We have the F-15E to replace the F-111. The E does a pretty good job. The problem with what you are asking for is you will never get that aircraft as it does not exist right now and probably won't due to expense. A lot of the stealth is accomplished by the use of RAM. Flying at high altitude adds a high degree of maintenance to keep the RAM functioning as it should. Now put that on a low level high speed aircraft. The cost would go through the roof. Low level with terrain masking provides a sufficient enough defense against SAM and AAA threats, currently.

Ozair, you by chastising me for bringing up the losses in Vietnam have confirmed my statement. Medium level bombing is better, I agree. However, you have to neutralize the SAM threat. That was done in GW1 by the "Secret Squirrel" operation, the F-111 and the F-117. Once that was taken care of, then you had the medium level sanitized enough to allow a fairly risk free ingress/egress. That's what happened in GW1.

You chastise me, again, for the F-111 statistics in Vietnam. However, they are the only statistics we have. Had the systems been more mature, the Aardvark's loss would have been much lower. Personally, I think it was a big mistake to send them but that's with 20/20 hindsight.

I don't know what the poster's backgrounds are in this thread, but I have been in military (USAF) as a pilot, only 11 years active duty and 11 Guard. So, my experience is pretty limited but I can categorically tell you nothing beat the 111 down low. If you have SAMS or radar guided AAA, the threat is much lower with those low level than anyplace else.
If we weren't all crazy we'd all go insane!
 
mxaxai
Posts: 651
Joined: Sat Jun 18, 2016 7:29 am

Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 12:19 pm

Faro wrote:
I wonder what with low-observable, stealthy radar as installed on the F-22, F-35 and other 5th generation fighters...are we not back to the era of pure BVR air-to-air engagements as prematurely posited in the 1950's?...if you are stealthy and cannot be detected, and can use your radar in long-range microbursts to detect enemy aircraft and launch air-to-air and air-to-ground weapons while remaining yourself undetected...then low-level high-speed penetration, dogfighting and cannon fire may perhaps become obsolete...

In the long-term, grand scheme of things, perhaps Vietnam will prove to have been a false positive...


Faro

I wonder what you expect a fight between two stealth fighters to look like?

Also, the issues with missiles in Vietnam were closely connected to the need to identify the target first. If they had wanted to, the fighters over Vietnam could have engaged in BVR combat. The missiles and systems wer built for precisely that.

Further, low level penetration of enemy airspace is not for fighters but for bombers. A fighter has no business down there. But cruise missiles, stealth and advanced radar make that role mroe and more obsolete.
 
Ozair
Posts: 2980
Joined: Mon Jan 31, 2005 8:38 am

Re: Swing Wings: How Did They Die Off?

Mon Feb 19, 2018 8:26 pm

mmo wrote:
Ozair, you by chastising me

mmo, my intention was never to chastise you, if it came across that way I apologise.

mmo wrote:
I don't know what the poster's backgrounds are in this thread, but I have been in military (USAF) as a pilot, only 11 years active duty and 11 Guard. So, my experience is pretty limited but I can categorically tell you nothing beat the 111 down low. If you have SAMS or radar guided AAA, the threat is much lower with those low level than anyplace else.

We all have experience that we bring to airliners, along with our bias and preference. That is why I like posting here, because we have so many viewpoints which provide for sometimes provoking discussion that can challenge the conventional wisdom. It would be rather boring if we all agreed on everything.


mmo wrote:
Low level with terrain masking provides a sufficient enough defense against SAM and AAA threats, currently.

The problem I have with this statement is that isn’t what happens today. Western powers don’t go in at low level because of the Sam threat, they neutralise the SAM threat while flying medium to high level, precisely because the threat environment down low is so hazardous. If you look at Red Flag exercises, the aircraft spend so little time down low compared to medium and high level bombing and the whole point of flag is to train the way you fight.

mmo wrote:
However, you have to neutralize the SAM threat. That was done in GW1 by the "Secret Squirrel" operation, the F-111 and the F-117. Once that was taken care of, then you had the medium level sanitized enough to allow a fairly risk free ingress/egress. That's what happened in GW1.

The SAM threat persisted lost after the first night/day and the below shows clearly how the USAF conducted their air campaign.

the United States air commander in the Gulf, Lt-Gen "Chuck" Horner, said: "I don't think there's any doubt about it. The Tornado losses were in part due to the low-altitude tactics." Lt-Gen Horner suggests that he was relieved when the British changed their tactics, but said he could not force them to.
The RAF had 45 Tornado GR1 jet bombers in the Gulf when the war began on 16-17 January 1991. In exercises simulating a war against the Soviet bloc, the RAF had developed tactics of low-level bombing - down to 50 feet during daylight - to avoid radar when attacking heavily defended targets.
The RAF used the same tactics at the start of the Gulf war. Apart from the very first night, the Americans flew at medium (15,000 to 20,000 feet) and high level.

http://www.independent.co.uk/news/brito ... 21938.html


mmo wrote:
You chastise me, again, for the F-111 statistics in Vietnam. However, they are the only statistics we have.

I am a big fan of finding data to support conclusions and think that Vietnam study is about as close to pure data we can find on the capability and ability of the respective USAF aircraft in Vietnam against the ground threat.

mmo wrote:
Had the systems been more mature, the Aardvark's loss would have been much lower. Personally, I think it was a big mistake to send them but that's with 20/20 hindsight.

Agree that the F-111 was deployed too early. Not sure it would have changed the loss rate given the air threat present in Vietnam at that time.

Apologies to all, we have drifted very far off topic...

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