pfcemWhat do you propose?
Close our eyes and pretend we cant see?
No, learn something about aerodynamics.
Marcel Dassault used to say “if it looks beautiful, it flies beautiful”.
That was Marcel Dassault!
So. Does not make it a true statement.
On the other hand, we still have hard data.
Wing thickness, sweep angle, bypass ratio all make for an excellent subsonic aircraft but act as huge airbrakes in the SS region.
No, all make for an excellent TRANSONIC aircraft but not a Mach 2 aircraft.
If that is the case, than you can probably answer why all these years fighters had external stores, and not internal as in WWII bombers.:rolleyes:
I already did.
True but only carried a portion of the trip, while the extra structure skin and panels are riveted all the way.
So?
Currently yes, it does function and does changes the game.
But how about 6 years from today?
Will still be a game changer. Almost every current & future major combat aircraft project includes stealth…
In the class of the F-15/F-16. Without stealth it is going backwards.
No it isn’t. The dry thrust of a F-15C in an aircraft not much larger than a F-16…that can carry as much fuel (plus two AMRAAM & two 2000 lb JDAM or eight ‘250 lb’ SDB internally) as a F-15C can with one 600 gal external tank.
pfcemHave you even considered the difference in length between F-35 and F-22 and considered the effect of cramming a bigger load into a shorter airframe?
Hint; think of frontal area.
The frontal area of the F-35 is SMALLER than that of the F-22.
pfcemMy point is that aerodynamically it is more efficient to carry 2 bombs (or even 4 SDB) plus 2 drop tanks externally than internally. I am comparing apples with apples, here.
What is yours?
NO IT IS NOT! Not even close. If it were there would NEVER have EVER been ANY aircraft that carried ANYTHING internally (since carrying it externally would be more aerodynamically efficient).
Of course it wont. Never said so.
I consider the F-35 an excellent strike aircraft plus a VERY potential BVR fighter. Because of stealth, just that, and only that!
The avionics suit is very impressive but as I wrote avionics can be incorporated in almost any fighter.
Even WITHOUT stealth the F-35 will be a very good BVR & WVR fighter.
You MIGHT be able to shoehorn the F-35s avionics into a F-15 or a Flanker but there is NO WAY it will fit into a F-16 or F/A-18 or Rafale or Typhoon or Fulcrum.
What I am trying to tell is that by the date this aircraft is going to see service, stealth features might (and most probably will) be canceled by radar innovations and new technologies.
LOL
I know you are sure that these will never happen, and if it does the effect will be minimal, I ve heard this argument a million times…
but …
just for a second, just for the argument’s sake try to imagine.What would that mean for the lightning II?
It would STILL be a very good BVR & WVR fighter and strike aircraft with several OTHER advantages over 4th generation “competitors”. The F-35 is NOT a F-117, it has MUCH more going for it than just stealth.
pfcemYou have an obsession with this “clean” configuration concept.
No obsession, just a good enough understanding that ‘clean’ is MUCH better than ‘dirty’.
But however odd it seems, the “dirty” configuration is in fact, and in most of the cases, more efficient.
No it is not, NEVER is ‘dirty’ more efficient than ‘clean’.
That ‘s because drop tanks, after the first 10-15 minutes of the flight, are ejected or drop t, hence the phrase “drop tanks”.
:rolleyes:
Well now we all know just how ignorant you REALLY are.
And in most 3rd or 4rth generation fighters 2 small bombs and 2 A2A missiles do not pose all that drag, and are carried only half the flight time.
On the contrary a stealth aircraft must carry extra structure, skin and opening panels all the way back…;)
You are forgetting 2-3 external tanks…and 2,000 lb JDAM are not small bombs.
The ‘extra’ structure, skin and opening panels is NOT EXTRA, it is what is needed to pack all that stuff inside & does not pose anywhere near the drag of external stores.
True, but only because of stealth, and as long as it functions.
Stealth is NOT the only advantage the F-35 has over 4th generation fighters & it DOES function (& in such as way that it changes the game).
Also true. but doesn’t this sound an regression?
:confused:
pfcemSo we need to build more F-22’s because Russia sold 30-40 Su-30’s to India and a dozen or more to Malaysia and Indonesia? I don’t know how many Su-30’s Venezuela bought but I’m sure its not 700+ units.
No. For a LOT of reasons…The proliferation of advanced Flankers is only one.
Keep in mind that the USAF says it HOPES (I say it is dreaming) too keep 178 F-15C’s ‘Golden Eagle’ in service beyond 2025 to AUGMENT the 381 F-22 is needs.
Yes if you make more the price will go down but why spend money on an aircraft that was designed for only one role, A2A. Oh yeah, Lockheed managed to tack on a limited A2G role but a 90mil multi-role F-15E is a lot better than a 120mil F-22 that can only carry a couple of JDAMs.
Because life is a WHOLE lot easier when YOU control the skies over the battlefield rather than your adversaries and we HAVE to replace our F-15Cs which by 2010 will all have flown more than TWICE their intended airframe life.
And depending on the target (& more importantly what you have to go through to get that target) the F-15E doesn’t stand a chance against the targets the F-22 can deal with…
That’s what it comes down to in this day and age, economics, more bang for the buck. The F-35 is a true mult-role and therefore a more cost effective aircraft considering how many are planned and how many other nations are involved in it.
The F-35 is more cost effective for SOME things, the F-22 is more cost effective (especially the more effective part) for others. The hi-low mix WORKS.
Something else to keep in mind the F-22 avionics date from the mid to late 90’s, its tech is already pushing 10 years old. The avionics on the F-35 are more advanced and more flexible.
So you not realize that updates for the F-22 are already planned & could in fact be incorporated into new build aircraft…
As for what happens 30 years from now, again look at economics. Do you see any nation in the near future that will have the economy to support a large number of F-22 like aircraft. Both Russia with PAK-FA and China with J-XX don’t seem to be in any hurry to rush those aircraft into production. If they do put both designs in service in say 10 years from now the F-22 design and avionics will be 20 years old. Considering what’s going on right now with the global economy the world’s militaries better be happy with what they have right now for an extra few years.
You are so hopelessly ill-informed that it is not even worth the time to TRY & explain it to you.
Yeah it may be nice to have the coolest, fastest most tricked out hotrod in da’hood but what good is it when you can’t afford to put gas in it.
:rolleyes:
pfcemAsking about what capable enemy did the F-15 fight brings us back to the first point. Is the F-22 a waste of money?
I agree that the F-15 has been flown by some of the best trained pliots in the world. The US, Israeli, Saudi, Japanese and now South Korean and soon Singapore. All have well funded armed forces. Its opponents have been lesser trained and equipped. The Serbs had the best training of the Eagle’s adversaries but let’s face it they had the “export” MiG-29A’s and were trained in the old Soviet style of relying on ground controllers. If the F-15 is still the king of the hill just replace the old F-15’s with new builds with new avionics instead of building the pricey F-22.
The F-22 was designed in the mid 80’s to go into service in the mid 90’s to face the Soviet fighter hordes however the Soviet Union collasped and the F-22 program was delayed and scaled back like the Eurofighter and the Rafale.
IMHO the F-22 is a waste of money and resources in the current environment but the program was really too far along when the Cold War ended and it was the US Air Force’s baby and they weren’t going to kill it.
Ibsolutely GREAT example of the ignorance & short sightedness of F 22 opponents!
Sure the F-15 has done well against adversaries IN THE PAST but what about 10, 20, 30 years from now? And since you appearantly haven’t noticed Russia has been exporting weapons as (& in some cases MORE) advanced that it itself has been acquiring. And if we would procure enough of them, the F-22 would not be THAT pricey. A F-22 at ~$120 million would be a steal compared to a ~$90 million F-15.
pfcemThe present data at hand are a nightmare for the F-35.
What data?
If fact the present data at hand indicates that while not likely having the supersonic flight performance of a F-22 or Typhoon that it will have AT LEAST as good (& most likely better) subsonic & TRANSONIC flight performance as a F-16 & given that it will FIGHT in a CLEAN configuration should be a major concern for any 4th generation fighter WVR.
Add to that all the other 5th generation advantages the F-35 has & 4th generatoin fighters have MUCH more to fear from the F-35 than the F-35 has to fear from them.
It seems, that building something for best stealth does compromise other areas to a high degree.:eek:
BS. Case in point -> F-22. And contrary to the naysayers, the F-35 is much more F-15 & F-16 than A-7…and much more F-22 than F-117.
pfcemBeing only slightly lighter, but having less thrust and being smaller-winged than a Super Hornet the A sure won’t set any new records in combat configuration. B and C will be worse (+1500kg, the larger C-wing can’t offset that).
I expect – with comparable load (which would mean 2 drop tanks, 2 AMRAAM, 2 JDAM, plus the awkward pylons for the Super Hornet) – the F-35A to have about 33-40% larger combat radius than a F/A-18E, or about 550nm max. As soon as the F-35 uses external stores that advantage will drop to 15-20%.
repost from my post #290
OPERATIONAL EMPTY for production aircraft
(I bet most incorrectly still use the pre-weight reduction number)
F-35A: 26,600 lbs with 28,000 lbs dry & 43,000 lbs afterburn thrust
for comparission
F-15C: 28,600 lbs with 29,200 lbs dry & 47,600 lbs afterburn thrust
F-16C Block 50: 19,100 lbs with 17,150 lbs dry & 29,600 lbs afterburn thrust
F-16C Block 52: 18,335 lbs with 17,800 lbs dry & 29,100 lbs afterburn thrust
F/A-18C/D: 23,050 lbs with 23,800 lbs dry & 35,400 lbs afterburn thrust
F/A-18E/F: 30,600 lbs with 28,000 lbs dry & 44,000 lbs afterburn thrust
Rafale C: 20,000 lbs with 22,500 lbs dry & 34,000 lbs afterburn thrust
Typhoon: 24,250 lbs with 27,000 lbs dry & 40,500 lbs afterburn thrust
Mig-29S: 24,250 lbs with 22,500 lbs dry & 36,500 lbs afterburn thrust
Mig-29M: 25,600 lbs with 24,250 lbs dry & 38,800 lbs afterburn thrust
to add
F-35C: 30,000 lbs with 28,000 lbs dry & 43,000 lbs afterburn thrust
And even though wing area is not an accurate measure for flight performance…
F-16C: 300 sq ft
F/A-18C/D: 400 sq ft
Mig-29: 408 sq ft
F-35A: 460 sq ft
Rafale C: 492 sq ft
F/A-18E/F: 500 sq ft
Typhoon: 551 sq ft
F-15C: 608 sq ft
F-35C: 662 sq ft
The exact thrust on the JSF isn’t known, other than it’s in the 40,000lb+ class. The SH has ~44,000lb in current trim.
Oficcially according to Pratt & Whitney it is 28,000 lbs military thrust & 43,000 lbs at full afterburner.
Also note as I pointed out earlier the bypass ratio for the F135 (0.56) is half way between that of the F100-PW-229 (0.40) & the F110-GE-129 (0.76). The F414-GE-400 & EJ200 are also 0.40
pfcemThe total range of the F-35A is 1200 nm on internal at subsonic, which is no more than Mach 0,8 at height. When someone has better data he can post that. By the way a capability demonstrated by a F-16A in the 70s. 😀
No, the typical combat mission radius (with two 2,000 lb JDAM & 2 AMRAAM) KPP threshold is 590nm & by extension total combat flight range ~1200nm. It is NOT the ferry range with internal fuel.
The typical yardstick to measure the range capabilities of a design is the ferry range without air-refuelling.
No it is not. Not in the 21st century anyway.
A F-35A does burn 36 tons of fuel per hour in full AB at low level,
still 18 tons at medium heights and not below 9 tons very high up.
Says who? Besides, what does the fuel burn at full afterburner have to do with anything?
pfcemI think that is where the misunderstanding lies. Nobody says the F-35 won’t be supersonic capable, but people understand that its supersonic performance is for sure sufficient for the F-35s missions, but likely to be inferior to other, more optimised designs. That is however countered with arguments like internal fuel and weapons carriage which is of course somewhat true, but you guys do also ignore the importance of the aerodynamics and the fact that raw uninstalled specific thurst doesn’t tell you anything about supersonic or altitude performance.
No, the misunderstanding lies in just because the F-35 is not designed to supercruise like the F-22 that it DOES NOT mean that it is not capable of supercrising (in the sense that a number of 4th generation fighers can supercruise).
I sure as hell am NOT ignoring the importance of aerodynamics, I just happen to know JUST enough about aerodynamics (& have read comments from those I know know more than I do) to know that the aerodynamics of the F-35 are better than its naysayers are implying. They say it is a “fat pig”, well guess what then the F-22 is a “fat pig” yet it can SUPERCRUISE at Mach 1.72.
While uninstalled specific thurst alone doesn’t tell you enough about supersonic or altitude performance it DOES tell you about potential. Just read the comments from the F-35 test pilots, they are contually have to throttle back too keep it from flying too fast & the chase planes often have to touch the afterburner took keep up.
Are the weight figures for the F-35 OEW? As I understand it it’s just the empty weight. And according data about the F-15C I have its EW (not OEW) is 28160 lb.
Yes OEW. To aircraft manufactures & operators pure physical empty weight is all but meaningless.
Sources say everything from, 28,000 lbs to 29,000 for the F-15C but MOST (& the most credible) say 28,600 lbs OEW.
And the prove is? Don’t get me wrong, but you guys on one site complain about how could we know that other aircraft are more aerodynamic, while the other way round you claim the opposite in the very same way!
Prove what? That the F-35 is SIGNIFICANTLY smaller in every way than the F-15 & that everything except wing sweep angle is more aerodynamic on the F-35.
I perfectly know this, what I’m referring to is that the F-35 is definitely draggier by that in a clean configuration. Whether that’s important for operations or not, but that’s the way it is.
But a CLEAN F-35 is less draggy than its 4th generation “competetors” with external stores (weapons & drop tanks). The F-35 is a model of aerodynamic & space efficiency. I carries as much fuel as a F-15 with one 600 gal drop tank PLUS two 2,000 lb JDAM & 2 AMRAAM internally in an aircraft the size of a Rafale!
pfcemPage 8 of that brief has some trouble. Drop tanks won’t be certified by the end of SDD (“dropped” as per a DOD contract in 2006 maybe a later date under later notional Block listings under “range improvement”.)….nor external carry of JDAM (External AIM-120s, External JDAMs,External JSOWs are probably Block V… and well that is “notional”… meaning that they aren’t sure.) Logical since there is such a short amount of test flying on the books.. One other error toward the bottom: The UK Paveway IV (small version) will be certified by the end of SDD. That slide is wrong by not having it marked in purple.
Indeed. I HATE it when even THE sources don’t update all their information…
“As a matter of comparrison, the F-35B carries about the same amount of internal fuel as an F-15C.” Interesting. But the STOVL will be a 6.X G jet. The C, 7.5G and the A a 9 G. They are strike aircraft that fall more into the heavier wing loading arena, not air domination.
No, the F-35C, just like the F/A-18 will be cleared for +9g during war but limited to +7.5g during peacetime operations.
The F-35B has a +7.0g rating.
An aircraft today does not have to have been designed specifically for air domination to be a good BVR or WVR air-to-air fighter…
“…in which case a F-35A with TWO 600 gal external tanks carries…” Besides the fact that drop tanks for the F-35 are not on any funded list, the ones that were before 2006 were 426 gal ones. Then too if one believes LM’s latest sales brief to Norway where LM fibs about non-existent external tanks and F-35 range, those tanks don’t add much range. Most likely because of weight.
I was just making a point about how much fuel the F-35 carries INTERNALLY (which just so happens to work our quite closely in said examples), thus MUCH LESS need for external drop tanks. External drop tanks for the F-35 would probably only be used for ferry missions. When a F-35 needs more fuel than it can carry internally, it will most likely get it from a tanker.
We will know what a real F-35A weighs when one is actually produced (AF-1) and flying for some time with war systems. That is a long way off.
IIRC AA-1 came in within 150 lbs of its projected weight so there is little reason to doubt that the production models will not also come in quite close to theirs’.
However back to the Norway brief. The best cruise was at 25k feet. Me-thinks Tornado and B-1.
No, for the F-35 the Norway brief says “The resulting radius is 740 nm (or total distance of 1480 nm). The range of altitudes during the cruise is 33,200 ft to 40,400 ft“.
pfcemIt’s not just limited delta wing aircraft, but it is not unreasonable to assume that a relative fat aircraft, with low wing sweep angle and relative thick wings is not going to be an ubber supersonic performer, regardless of specific uninstalled static thrust.
Nobody is saying that the F-35 is going to be an ubber supersonic performer. What IS unreasonable however is to assume that it won’t be a supersonic performer. Again, we are talking about an aircraft about the size of a Rafale (a bit “bulkier”) but with the dry thrust of an F-15C (or only about 1,000 lbs less dry thrust than an F-16C Black 50/52 at full afterburner).
Notably bigger yes, but heavier? Inform yourself the F-15A/C weights actually not more than the F-35, despite being bigger. And less aerodynamic by what measure (excluding external stores).
Yes heavier. The operational empty weight of the F-15C is about 2,000 lbs more than the F-35A, the F-15E (probably a more fair comparision being a mutli-role fighter-bomber like the F-35 rather than a pure fighter & with a MUCH closer fuel fraction) about 5,000 lbs more.
By any measure, even a clean F-15 is less aerodynamic than a F-35.
These CFTs will have an impact on performance nontheless, not as much as external tanks but still an impact. You can’t completely neglict the additional weight and drag and that is one of the reasons why people say just take a look at the F-35 it was designed as a fat lady to carry all its stuff internal.
You missed the point, 4th generation fighters are being (or soon will be) fitted with CFTs because they need to carry more fuel than they can internally & CFTs are MORE effecient than drop tanks. And having enough internal fuel capacity is more effecient than even CFTs.
The F-35 is simply to small to appear sleak, like the Raptor does for example.
Exactly, but just because the F-35 does not appear sleak does not mean that it isn’t. Sure it isn’t a F-104, but it ain’t no F-4 either.
pfcemEmpty weight, empty weight, empty weight. If the F-35 stays above 11.5 metric tonnes empty it will always have a problem.
What makes 11.5 metric tonnes the “magic number” for the weight of the F-35 not to be a problem?
Since the current F-35 is pretty conventional inside (structures, materials, manufacturing technology), I think there is still a considerable amount of weight saving potential, so it might just reach those 11.5 in future incarnations (I’m not very confident).
Sure but at what $ cost???
What would of course help, is to build only one uncompromised version.
Even though the original concept of commonality across A-B-C has turned to a farce more or less, the influence of the B version on the others is still there. I seriously think that a re-design of the F-35 right now would be the best option, even if IOC slips another year+.
So commonality only works if it is 80+%? What do the other services do when you build only one uncompromised version?
That fuel fraction thing: For a legacy fighter(bomber) drop tanks are more efficient than large internal volume, as long as he stays clearly subsonic (see some Rafale configurations). If he wants to go trans/supersonic he needs to have tanks that fit into the area-ruling of the overall air vehicle (see Mirage 2000 tanks), plus needs a head-on cross-section as small as possible (that’s why Concorde is long-and-thin, and not thin and wide). Since the F-35 wants to be LO, only stealthy and area-ruled canoe-shaped drop-able fairings would be an option, but that would still pose a problem for maneuverability because of large masses away from the roll axis. (Such fairings could be an option for a clip-on fighterbomber module for a LO fighter — too late for F-35). There is no way to retain a carrier-lift compatible length AND have large internal volume AND internal weapons AND be a good supersonic performer. The F-35 is a compromised compromise in a lot of ways, that will make it a nice subsonic fighterbomber with supersonic dash capability, but for sure no fighter.
BS. Even ignoring stealth, the F-35 will be a better fighter than the F-16 & F/A-18.
pfcemOnly on dry thrust. Higher bypass ratio = less efficiency on the afterburners.
You obtain your best range on dry thrust…afterburners are used sparingly. Specific fuel consumption for engines at full afterburner is about 3 times (varies with engine, I have see as low as ~2.5 & as high as ~4) that at dry thrust.
And there is a reason why fighters don’t use civil high bypass ratio turbofans either.
Because civil high bypass ratio turbofans are designed for optimal fuel efficiency at a specific speed at a specific altitude. Fighters don’t fly that way, they are MUCH more about flight performance over a MUCH wider range of speed & altitude that the best possible fuel efficiency.
Note that civil high bypass ratio turbofans have bypass ratios >4.0:1 with the latest generation of engines for the Boeing 787 & Airbus A350 being >8.0:1.
The bypass ratio of the F135 is “just” 0.56:1. By comparrision the F100-PW-229 is 0.40:1 & the F110-GE-129 is 0.76:1.
***
To get a simlar range, they did carry ETs and can drop that when empty. By that a F-15 has an advantage over the Su-27 f.e.
No, it is the other way around, to get similar (or greater) range the F-35 does not need external tanks.
To be stealth has a price for the F-35. Surplus internal volume at a given moment has its price in surplus weight and drag. 😉
What price? Stealth does not require “surplus internal volume”. The F-22 & F-35 are NOT the F-117, the US no longer has to sacrifice flight performance for stealth. Hell being “big” no longer requires a sacrifice in flight performance, just look at the Flankers & the F-22.
***
BTW I would like to see any range figures for the F-35. Everything I have seen so far doesn’t look that impressive, especially if you take into account the huge amount of fuel. So far the claim “longer time on afterburner” has yet to be proven.
You aren’t going to see any actual numbers for the F-35 for some time. For now all we REALLY have is the REQUIREMENTS.
KPP threshold
F-35A: combat radius >590nm (range >1,200nm)
F-35B: combat radius >450nm (range >900nm)
F-35C: combat radius >600nm (range >1,200nm)
The Jan 2008 Program Overview shows all three exceeding these KPP thresholds.
***
Before doing such nonsense claims you have to compare the fuel fractions.
The F-35A is at 0.38 at 100% internal.
The Typhoon is at 0.** at 100% internal and is at 0.** at with ETs.
The former US claim was that the ETs could be dropped after half way out and the internal is still enough for one hour of flight time at least.
That all in mind to reduce drag and dead-weight, when going into combat.
See the F-15, F-16 and F-18 about that. That was called tactical flexibility.
No, not having to carry external fuel tanks is tactical flexibility.
To stay stealth all the time the F-35A has to sacrify that tactical flexibily.
But the USAF had changed their mind about that to correct the shortcomings in their overweight stealth-fighters and did add some ETs to restore range and by the tactical flexibility, when not in urgent need of stealth. :diablo:
BS. The F-35 can fly farther than any 4th generaton “competator” WITHOUT HAVING TO CARRY EXTERNAL TANKS! Being able to be stealthy when needed OR carry additional external stores when stealth is not neccessary IS flexibily.
pfcemDo you know that the CONCORDE could supercruise at M2.0 since 1970??
Do you know the installed thrust, weight and size of the aircraft?
Yes I do.
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