eagleAre you two looking at the same charts? You are looking at B8-49 and B8-50, yes? The F-35 specs were obviously written for a block 50 with a DI of 50 (basically as low as practical considering pylons and two amraams). I agree with what you said 100% here.
Yes, B8-49 and B8-50. 5.52g resp. 6.17g at 15k feet are just average values obviously so it’s not 100% correct.
The original objective was 6+g with a threshold of 5.3+g. Current threshold is 4.6. Observed performance of the heavier 240-3 configuration was 4.95g, sustained. The F-35 did not meet the planned threshold. It is most likely between .35g or less off the original threshold. That translates to a roughly 1 degree per second difference (in the worst case scenario 4.6g, based on the 4.95g observed performance= less than 1 degree per second difference). Break out the pitchforks….
:dev2:
eagleWith take off weight = 22000lbs aka 218 kg fuel (6% of total internal fuel capacity) => sustain turn rate = 6.3Gs With Drag index = 0.
With take off weight = 26000lbs aka 2032 kg fuel (63%) => sustain turn rate = 5.3Gs with DI=0, 5.1Gs with DI=50, 5.2Gs with Drag index = 21.
With take off weight = 28500lbs aka 3227 kg fuel (100%) => sustain turn rate = 4.8Gs with DI =0, 4.4Gs with DI=50, 4.6Gs with Drag index = 21.
I don’t know how you read those Hellenic Viper charts. Note those are heavier airframes than their older standard USAF Block 50 counterparts, more or less Block 50+ vs. Block 50.
I got the following figures:
@ 0.8 Mach
15k feet, 22k lbs, DI 0: 6.55g
10k feet, 26k lbs, DI 50: 6.55g
20k feet, 26k lbs, DI 50: 4.49g
–> 15k feet, 26k lbs, DI 50: 5.52g
I didn’t bother with the rest.
If we allow the F-16 to fly where it’s best, at 0.88 Mach, the result is:
@ 0.88 Mach
15k feet, 22k lbs, DI 0: 7.45g
10k feet, 26k lbs, DI 50: 7.25g
20k feet, 26k lbs, DI 50: 5.09g
–> 15k feet, 26k lbs, DI 50: 6.17g
This gives a good hint where the objective of 6g sustained comes from if you ask me.
eagleThe same thing can be said about Su-27, PAK-FA, F-15, Rafale, F-14.. etc, how is it a problem?
It’s not a problem per se.
But I repeat: the F-35 has a greater part of its reference wing area buried in the fuselage because its fuselage is wider than the F-16s. The actual F-35A/B wing area is only ~25% bigger. Hence wingloading comparisons are somewhat misleading.
Even a tube will generate lift at positive AoA, but some design is more optimum in produce lift than the others
Yes a wing is more optimal than a fuselage.
kinda hard to compare here without specific figures, ” pretty much” is not accurate enough.
Based on the drawings I used, they’re exactly 53.8 % bigger. Problem is I don’t have accurate drawings of the F-35. But it is accurate enough to state that F-16 and F-35 stabs have roughly the same area relative to aircraft weight.
eagleReferences wing area always included the part within the fuselage
Exactly and because the F-35 fuselage is wide, a good part of the 42.7 m2 wing area is not wing area but fuselage.
The F-15 also has a huge part of its fuselage includes in reference wing area
Yes, so?
But that not what body lift mean. Even for aircraft without any body lift, if you have to measure lift at certain AoA, the part within fuselage is still included in references wing area when you use the lift equation, the only part that would change is the lift coefficient.
Not sure whats the point here. But there is no aircraft without body lift.
Moreover, both F-16 and F-35 are negative stability design, which mean their horizontal stabilator actually contributed to total lift instead of reducing it, and the tail fin of F-35 is actually huge compared to F-16
Sure, but the F-35 is also huge compared to the F-16. Relative to weight, the stabs are actually pretty much the same size (compared to an 8500 kg F-16C). F-16C is not unstable anymore though.
eagleWing loading – (empty)
F-16C: 307.5 kg/m^2
F-35A: 309.1 kg/m^2
So for the same fuel fraction, the wingloading for the F-35 and F-16 is nearly identical…. which would make the F-16 an ‘A2G oriented plane’…
(BTW the need for ‘stability’ in a strike platform went out with the advent of large scale PGM usage.)
If you use the reference wing area. Due to the wide F-35 body, the percentage of the 42.7 m2 wing area that is actually part of the fuselage is pretty high. The actual F-35 wing area is only ~25% larger for more than a 50% weight increase. Also, later model F-16s are not known for their low wing loading. Then again, even 10 tons empty weight seems to work fine with the F-16 wing (F model), but an air superiority fighter it is not.
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eagleThe 1982 Lebanon Air War was fought entirely Beyond Visual Range.
Sure, with more than half the kills (44) credited to Sidewinder only F-16As. :very_drunk:
eagleYes. Because the AFX was a 10,000lb warload airframe with specifically stretched and deepened weapons bays to allow for the added payload and the USN were willing to go either way on the PW7000 (F414 EFE) engines on supercruise but would not abandon the range:payload formula of the A-6 replacement which they were after.
JSF isn’t AFX. The Navy actually tried to add as much as they could to the JSF program from their heavy attack req., like the 2000 lbs bombs and A/G targeting system for every aircraft. But to think the DoD would have let the Navy turn the JSF program into another AFX desaster after they failed on numerous attempts is completely out of touch with reality.
I’m not saying a different airframe wouldn’t have been better. Better luck next time i.e. FA-XX.
I don’t believe it. This is a core based on the 2+ F119 with a monster fan and a 51″ case diameter compressor section, like the F101. It runs hotter. It has more thrust in both AB and Military. And yet you want me to believe that it has greatly improved TSFC. And I’m telling your wrong.
It is an F119 core with a bigger fan @ 0.57 BPR. So yes it has improved SFC compared to the F119.
You don’t believe official data but your made up stuff is ok… that air show ferry flight story is not official data. Pilots may tell many things, some correct, some less. If they were always correct, F-16s would carry nukular bombs on airshows all the time.
I don’t know you from Jack so just because your screen name says ‘Eagle’, don’t think I owe _you_ trust I refuse to give the walking RICO charge that is our military.
What I can tell you is that in the time frame since I first posted the above, Wikipedia has removed the .889pph TSFC figures for the F135 and now the only way you can see the data point is via the Way Back Machine of historical page edits which they keep. Mind you, they did not replace it with a figure that is a little more friendly to their agenda. They just removed the TSFC figure altogether. Which suggests that the original figure is the correct one and they would rather we all drink bleach and forget than be caught in ANOTHER lie. A lie implicit to the .7pph figure of the F100 series which they would have to erase half the internet to remove.
What’s my nick got to do with anything.
Wikipedia has removed the SFC figure because “Specific fuel consumption data removed – the source referenced https://www.pw.utc.com/Content/F135_Engine/pdf/B-2-4_F135_SpecsChart.pdf doesn’t actually contain that data and no alternative source can be found that doesn’t copy or reference this page”. Which suggests the 0.886 lb/hr·lbf figure is pulled out of thin air (by you? 😀 ). Notice the figure translates to a nice round 25.0 g/kN·s. Really?
You don’t need the way back machine btw., wiki stores all edits and previous versions of a page. The version you’re looking for can be found here:
https://en.wikipedia.org/w/index.php?title=Pratt_%26_Whitney_F135&oldid=723079337
Ask anyone, I despise Israel. The United States is not the mule of that nation’s genocidal plan to reconstitute a biblical state by slow-slaughtering the Palestinians in a Warsaw Ghetto like environment using 3 billion dollars per year of our FMS as an IG Farben equivalent war crime, for U.S.
I see, but I’m not surprised, at the end it usually boils down to the great zionist world conspiracy with the tinfoil hat brigade. Now the zionists are responsible for the F-35 having a combat radius of 150nm aswell and they try to cover it up by deleting info on wikipedia. :very_drunk:
eagleRange of flight 2,200 km – the official information from Lockheed. Really can be smaller – 1,850 km.
Maximum take-off weight of F-35A with external fuel tanks 31750 kg. Fuel 8382 kg. The relative weight of 8382 kg Fuel: 31750 = 0.26 kg
Why don’t you work with the radius provided in the official information from LM?
As I’ve already mentioned, that is actually a known number. Based on radius, I guess range is about 2500 – 3000 km.
If were talking ferry range, fuel fraction is ~ 0.38, same as Su-35, from what is known at least.
No external fuel for the F-35.
eagleBecause we would have had a twin and probably low end supercruise, with FOUR 2,000lb class weapons (16 GBU-53/SPEAR-3)
Seriously, you think without the STOVL constraints, the JSF would actually be a supercruiser able to carry 4 2000 lbs bombs? Right :highly_amused:
It was the Navy who asked for 2000 lbs bombs. Without the C model, JSF would carry 2 1000 lbs bombs. Without the STOVL requirement, USAF would have stuck with that.
Indeed, let’s look at the F-35 radius shall we? If you take IRT as 27Klbf and Flight Idle as 60% of that or 16.2Klbf, and assume you tank before crossing the fence, you are functionally talking about .889 X 16.2 or 14.4Klbs of fuel burn to crawl along at 300 knots. Remove 2,000lbs from the total fuel load as unuseable fuel coolant and another 3,000lbs as combat reserve for 550 knot transit of the last 50nm to the target and you are talking with an 800lb ullage swing, you are talking about exactly 1hrs flight time or 150nm, in and out.
Actual fuel burn @ M 0.75 and 40k feet is 593 gal/h or about 3960 lbs/h.
The radius of ~590nm is a requirement and with a bit of tweaking (more optimal profile and factoring in some risk reserves) will be something like 620nm, don’t know the actual figures off the top of my head. Not great, but far from your ridiculously low figures.
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eagleWhich is still way better than anything the Su-50 will likely see.
Su-50? There is no such thing.
The T-50 might enter service as Su-37, Su-39*,… or even Su-50, if the Russians follow the US marketing BS. But right now, it is the T-50
* Yeah I know those numbers are already taken, but I have no idea if 37 and 39 are official designations or just marketing from manufacturers.
eagle2200 km * 0.35 = 770 km
Try it the other way round:
1100 km (radius) * (1/0.35) = 3140 km range.
Since when did “radius of action” is half the distance of the flight?
It isn’t but it’s very obvious some powerpoint warrior simply calculated range = 2 * radius.
Because radius we actually know: ~600nm @ USAF profile. Range we don’t know.
eaglehttps://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress#Air-to-air_combat
Guidance or dumb luck? You decide. The aircraft is an F-105, which is 20m long or 7mm in this photo, so I make the miss distance to be about 300m, but the aircraft was still damaged.
http://www.ausairpower.net/APA-SAM-Effectiveness.html
Judging by the trail, the F-105 was a lot closer when it was hit. Something like 120 meters.
eagleCurrently there are no F-15E or C units (that I am aware of) slated to transition to the F-35.
48th Fighter Wing at RAF Lakenheath is scheduled to get 2 squadrons of F-35s in 2020. I thought they will replace the Es with the C squadron to disband. Or are the F-35s in addition to the F-15Es?
Anyhow, the F-15Es will not retire but find a new home.
Re the 1700 F-35s, while there are around 1000 F-16s and 300 A-10s in USAF service now, some years ago, there were 1400+ Vipers and something like 450+ Hogs iirc. Since 9/11 f.e., all F-16ADF, Block 25 and some Block 30/32 have been retired. The number of active F-16 squadrons is actually pretty low right now. They’re bringing back the 3rd squadron at Hill AFB and plan to bring back active squadrons at Eielson AFB too. Naturally, more F-35s are needed than there are F-16s and A-10s in service now, if USAF wants to reactivate squadrons.
eagleTo me it reminds me of SAAB B3LA (A38/Sk38) more that SAAB 105 (Sk 60). The design was pretty far gone and close to production desition when FMV (Swedish defence material administration) decided that they wanted to consentrate the resources on what became the JAS 39 Gripen. AMX designers studied SAAB’s work since it shares similar configuration.
You’re right of course, it’s a tandem design after all. I was mainly thinking about the higher mounted wing and intake location which these Saab designs all have in common.
In fact, the closest thing is probably Saab’s Eurotrainer proposal. I wouldn’t be surprised if the Boeing/Saab T-X looks like this:
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eagleF-4 and A-7 were both Navy planes the Air Force adopted after they had been designed. The F-4C was largely identical to the F-4B, the A-7D of course was a major upgrade, but still a Navy airframe, with the later Navy A-7E being more or less a D model with probe and drogue refuelling.
If you want to know what happens when the AF has its way with adopting a Navy design, take a look at the A-3 and B-66.
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