Amiga500And how can a jet engine reduce the drag from a given set of aerodynamic design of a airframe?
Sorry, I did not get the part that the F-35 will be redesigned anytime soon.
If it increases the allowable massflow through the engine, then there will be reduced spillage drag at high subsonic speeds. At supersonic speeds, duct pressure recovery (read: drag) is improved through the engine not effectively forming the same blockage across the entire duct.
A moveable ramp would solve the problem as well – but F-35 doesn’t have one (IIRC).
The advent core won’t see an in-service F-35 this side of 2025 though, so fanbois shouldn’t be getting too far ahead of themselves.
Amiga500Of course, EW will be employed with F-35. Your adversary’s IADS needs to pick the target’s signal out of the noise. Stealth reduces the signal, while EW increases the noise.
Concerning some methods of EW – That is a simplistic to the point of being inaccurate. Concerning others, it is 100% accurate.
Survivability of the stealth/EW combination is vastly superior to non-stealth/EW combination.
Not if the stealth/EW combination has to be combined on one airframe due to cost.
Physics, How does it work?
Long wave length radars pick up the approaching formation long before it gets into the disputed airspace. Appropriate counter-air assets are guided toward it.
You cannot jam search, SAM and airborne radar all at the same time without an awful lot of support.
Amiga500They are the same people who actually know what they are talking about like what the F-35’s capabilities actually are
Who?
Lockheed? Like they are going to admit it doesn’t do everything their BS powerpoint says it will.
USAF? Like they are going to risk congress telling them to GTF with more funding.
You need to realise you are being led up the garden path in terms of capabilities. Flashy electronics and reduced X/Ku-band signature aside, the F-35 has precious little going for it.
Exit question: If the F-35 cannot handle it without “heavy” EW support, what chance does a 4th gen asset from a country that does not posses “heavy” EW support have?
Pretty much the same chance as the F-35 without heavy EW support. Zilch.
But crucially, the other country didn’t pay twice the price for their non-capability… so they have the aircraft numbers available to have some running SEAD and/or EW support.
Amiga500hahahahahahahaha
Anyone believes an F-35 will ingress into a modern IADS without heavy EW support and escorts is simply living in a dream world.
Anyone with even a rudimentary grasp of radar observables will already be well aware of reality.
Amiga500The trouble with placing someone on ignore is that one often forgets why one did so, and so upon seeing more of their now hidden posts is disturbed by the possibility that one is missing out on useful, insightful, or entertaining posts. Fortunately, someone usually quotes the offending poster at some point and one is thus afforded the occasional glimpse into the horrors usually concealed. I am referring of course to SteveDickson, who is apparently seriously suggesting a correlation between an aircraft’s quality and its success outside the home market. Stay buried, guy…
That F-22 sure is a pile of sh!te isn’t it? 😉
Amiga500We can calculate drag from those external amraams, too.
Drag force (Newtons) = 0.5 x P x V^2 x Cd x A
P = Density of Air (kg/m^3) ~0.232 kg/m^3 @ 12,000 m / 40.000 ft
V = Velocity (m/s) ; Mach 1 = ~295 m/s @ 12,000 m
Cd = Co-efficient of Drag ; ~ 0.6 to 0.95 for rockets depending mostly on finnage, nose and tail profile
A = Sectional Area (m^2) ; ~ 0.025 m^2 for a 7″ diameter missile.Drag Force @ Mach 1 = 0.5 x 0.232 x 295^2 x 0.70 x 0.025 = 177 Newtons = 39.8 lbs
but we got 4 of them so 39.8×4= 159.2 lbs
lets call it 160 lbs of negative Force
ooooooohhhhhhh. You need to be very careful doing that.
The transonic drag rise that is often mentioned (and poorly understood) by many, is actually a rise in the zero lift drag coefficient.
Drag always increases with speed, but drag coefficient can increase or decrease with speed. It is drag coefficient that is the variable pertinent to “transonic drag rise”.
So that missile having a Cd of 0.6 in incompressible conditions (or a Cd of 0.7 at Mach 2) could have a Cd of 1.0 at Mach 1.
Are you definitely sure the Cd figures you have relate to @ Mach 1? If they are not Mach 1, they should not be used for other speeds (in this instance).
Amiga500Not so fast! In the AFA article they say that the F 35 has a combat radius at least 25 % longer than conventional planes. That why I insisted on 1/2(or more?) internal fuel. Because in real life, an F 16/16, Eurofighter, etc would need at least 1 EFT to match the F 35 combat radius, and this make any acceleration comparation with F 35 unfair.
Ahhh, stall the ball there!
If your accelerating to supersonic speed, then almost certainly you are about to enter combat. Which infers:
– you are significantly far into your mission so that your drop tanks are empty (or near empty) and can be dropped.
– you are not far from your airbase as you did not use drop tanks in the first place so fuel is not an immediate concern.
In both scenarios, for a 2+2 AAM load, the F-16 will almost definitely have lower transonic drag rise than F-35.
Amiga500It beats also the F 18 C which accelerates better than the E/F. A marine test pilot stated clearly that the F 35 B (less performant than the F 35 A) has a better acceleration thas the F 18 C. Now look at the attached graph.
Fair enough. I knew it could out-drag a hornet, wasn’t sure which one, so played safe by stating the ****ter hornet airframe.
Also, considet that the F 16C/F18C are in an ideal configuration: 2 WVR AAMs, provisions (i.e. pylons) for 2 BVR AAMs and 1/2 internal fuel (1.6 t for F 16C, 2.4 t for F 18C). Now consider the F 35 that has 6 AAMs and 4.2 t (that’s 1/2 internal fuel in F 35 case), and you’ll see that the F 35 won’t only beat an F18C, but also an F 16 C in real operational configuration.
Neglect the fuel load – its influence on overall drag is negligible at this operating condition.
I would also tend to discount the wingtip mounted munitions – their negative effect on zero-lift drag is more or less cancelled by their positive impact on lift-dependent drag (at least subsonically).
The big question (for me), is, “is the effect of the BVR pylons + missiles enough to put the F-16 behind the F-35 in acceleration?”
Personally, I doubt it.
Amiga500It will also be interesting to see what info comes out over time on the F35 and its EW capabilities, I remember some time ago they were looking at an F35/Growler type aircraft and were playing around with the idea of stealth pods ? This was pretty early in the piece, but have not heard much about it since.
The AESA should give them significant EW capability already.
Any stealth pods would undoubtedly go onto hardpoints… if the USAF had brains, they’d demand the pods have an identical OML to pods capable of housing SDBs or similar.
Amiga500I will give an example about that. When some F-35s are in need for some CAP they will do that and not tasked for another mission in that time.
Indeed.
It cannot be two places at once. Also, given the very limited bay capacity, it cannot easily swing from one mission to another mid-air.
Amiga500Wondering if you have a reference you could give for the KPI ?
Tom Burbage, Lockheed’s program manager for F-35 talked about it sometime back.
They are re-negotiating the requirement based on the F-35 having better acceleration than the legacy aircraft when there is a large AG loadout on both.
Amiga500F-35 can supercruise at Mach 1.2. Other good info.
http://www.airforce-magazine.com/MagazineArchive/Pages/2012/November%202012/1112fighter.aspx
The F-35, while not technically a “supercruising” aircraft, can maintain Mach 1.2 for a dash of 150 miles without using fuel-gulping afterburners.
“Mach 1.2 is a good speed for you, according to the pilots,” O’Bryan said.
The high speed also allows the F-35 to impart more energy to a weapon such as a bomb or missile, meaning the aircraft will be able to “throw” such munitions farther than they could go on their own energy alone.
There is a major extension of the fighter’s range if speed is kept around Mach .9, O’Bryan went on, but he asserted that F-35 transonic performance is exceptional and goes “through the [Mach 1] number fairly easily.” The transonic area is “where you really operate.”
That is outright lies; which is nothing less than would be expected from a Lockheed VP.
The F-35C missed its sonic acceleration KPI. It may beat the F/A-18 E/F, but that is no barometer for “exceptional” performance.
Amiga500How would you rank the worlds 5th genertion fighter designs?
How is it possible for anyone to take this thread seriously?
Only 1 of the 5th generation aircraft is in service and even it hasn’t flown in anger yet.
Of the alternatives, 4 are in various stages of the prototype phase and one exists only on computers.
Amiga500How is it possible that 2202 US helicopter pilots died during vietnam war while during the same war there were 5086 helicopters lost?
Easily enough.
Any chopper that develops a problem over the line is lost – as the amount of effort and risk required to recover it is not worth it…
So while the crew/passengers will be lifted by another chopper, the broken one will typically be destroyed by the US forces.
Amiga500Although it is still astonishing that nobody appears to have appreciated that the issues of hook shape and location relative to the landing gear are connected – it does seem like a fairly obvious dependence.
It was probably hoped/intended it would work OK for spares commonality.
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