The F-35 Thread

[RyboPops]

Drag Index?

 

Yes.

[Maximus_G]

that was quite literally the most vain and vapid attempt at humor ive seen in a long time. trying to first paint trump's use of the word fantastic as "too casual" and then further constructing it as "sleazy" has no basis in reality and takes the joke 2 orders into "i'm stretching really hard to make up something here guys" territory. the punchline, besides being completely forced, is utterly devoid of any semblance of wit.

 

the writers are confused, ambivalent, or at best completely unconcerned about the f-35 itself, and the joke (if i can even call it that) takes a crude scattergun approach to appeal to anti-trump sentiment, anti-lockmart and by extension, anti-military-industrial sentiment and f-35 opponents, while attempting to quietly skirt the f-35 itself to leave a backdoor open for those actually impressed by the aircraft.

 

in the end, the real sleazeballs here are the show's writers -- shame on them.

Sorry guys, i didn't want to turn it political.

[garrya]

Sorry to interrupt this vital discussion regarding the F-35's L33T K/D...

 

I have always heard of the F-35 having a rather bad TWR (which is believable given its M1.6 top speed).

 

Top speed is limited by dynamic thrust vs drag, it has nothing to do with Thrust/weight ratio.For example: F-16 has much higher thrust/weight ratio than F-4 or Mig-25. Yet both Mig-25, F-4 can have much higher top speed.

.Drag is depending on aircraft shape and size , without some complex CFD or drag tunnel experiments, it pretty much impossible to know for sure. Dynamic thrust of aircraft is mostly decided by inlet and engine design. For example: variable inlet often mean better dynamic thrust at high speed than fixed intake

 

 

 

 

However I've recently had a few people tell me that it can go from brakes off to angels 10 faster than a Viper... apparently this was part of an airshow demo. I am 99% sure it's total bogus, has anyone here heard similar claims?

 

F = ma

so a ( acceleration) = force/mass, however, the force here is not the thrust of the engine but resultant force which calculated by taking dynamic thrust minus drag. Since both dynamic thrust and drag varied with altitude and speed, it is not possible for you to estimate the acceleration from a simple T/w rati.

Moreover, it is rather meaningless to calculate T/W of 2 aircraft with different combat radius. An f-16 with same fuel percentage as an F-35 may have higher T/W but at the same time much shorter combat radius and time on afterburner

Edited March 4, 2017 by garrya

[WRAITH]

Well just got back from Avalon Air Show all I can say is Lockheed have done an awesome job.

 

The two F-35's that landed at RAAF base Adelaide have much that public has not seen yet. Just by talking to some pilots on the ground they tell you that what they do out side public view makes yesterdays planes look old in comparison to what can be done with F-35's.............. here is the 3rd of March flight and very much the same for today's flight...............

 

 

Although, I really loved the F-35, the F-16 demo was just as amazing and we had some clouds up there to capture the sense of speed and agility the mighty Fighting Falcon has and still manages to keep its place! :thumbup:

Edited March 4, 2017 by WRAITH

[garrya]

I call BS on it as well. I don't have hard numbers but I can't fathom how a slick F-35 could possibly have a lower DI than a slick Viper. Add that to the fact that the F-35 has a lower TWR (allegedly) and the laws of physics tell you that the Viper wins the TTC to 10k competition every time.

 

 

A clean F-16 has a Drag Area (Cd x Wing Area) of 8.92 ft^2. A clean F-35A has a drag area of 9.8 ft^2. The F-16 is 'cleaner'.

 

If we assume a six A-A loadout and no external fuel tanks but full fuel for the F-16, as if it just dropped a centerline then the F-16 has a Drag Area of 10.51 ft^2 and weigh in at roughly 15 tons. T/W= .97.

 

A 2020 F-35 with six AIM-120s would have a Drag Area of 9.8 ft^2. With 80% internal fuel (since the F-16 got to lose 22% of his fuel load) the F-35 would weigh 23 tons. T/W= .93(using sea level static thrust, but T/W is useless) and top speed of M1.6

 

Assuming same speed and altitude (this lets us normalize some of the factors so that we can use Drag Area instead of calculating Drag) the F-16 would accelerate at (T-D)/W=a

Adjusting rations to compare for the F-35 we get (1.48T-.93D)/1.53W=1.01a but a top speed of only 1.6M (placard limit, it has more thrust than needed)

 

This is for as clean of a combat F-16 as you get. Add fuel tanks or ECM and the drag and weight both go up resulting in a lower 'a'. Reduce fuel more out of the F-16 to simulate flying farther and you would be reducing it out of the F-35 on a near 2/1 basis.Which mean F-35 will get even better

Edited March 4, 2017 by garrya

[RyboPops]

A clean F-16 has a Drag Area (Cd x Wing Area) of 8.92 ft^2. A clean F-35A has a drag area of 9.8 ft^2. The F-16 is 'cleaner'.

 

If we assume a six A-A loadout and no external fuel tanks but full fuel for the F-16, as if it just dropped a centerline then the F-16 has a Drag Area of 10.51 ft^2 and weigh in at roughly 15 tons. T/W= .97.

 

A 2020 F-35 with six AIM-120s would have a Drag Area of 9.8 ft^2. With 80% internal fuel (since the F-16 got to lose 22% of his fuel load) the F-35 would weigh 23 tons. T/W= .93(using sea level static thrust, but T/W is useless) and top speed of M1.6

 

Assuming same speed and altitude (this lets us normalize some of the factors so that we can use Drag Area instead of calculating Drag) the F-16 would accelerate at (T-D)/W=a

Adjusting rations to compare for the F-35 we get (1.48T-.93D)/1.53W=1.01a but a top speed of only 1.6M (placard limit, it has more thrust than needed)

 

This is for as clean of a combat F-16 as you get. Add fuel tanks or ECM and the drag and weight both go up resulting in a lower 'a'. Reduce fuel more out of the F-16 to simulate flying farther and you would be reducing it out of the F-35 on a near 2/1 basis.Which mean F-35 will get even better

 

That's cool, but the topic was specifically about airshow performance.

[Hummingbird]

Top speed is limited by dynamic thrust vs drag, it has nothing to do with Thrust/weight ratio.r

 

and weight has a direct effect on drag.... I hope I don't have to explain why.

[garrya]

and weight has a direct effect on drag.

Induced drag plays minimal role when the speed is supersonic

 

These fastest aircraft such as Mig-25 , SR-71 achieve their speed by unique airframe shape, engine, inlet design. Not by being light and having high static T/W

 

I hope I don't have to explain why.

If you want to explain your point then do it. If you don't want to then don't. No need to announce it

[Pocket Sized]

Huh! I just sorta assumed the F-35 had less than great TWR due to its intended purpose and huge amounts of avionics. (Also the aforementioned WVR losses)

 

I also didn't realize the divertless intakes were that detrimental to performance but it makes sense.

[wilky510]

Huh! I just sorta assumed the F-35 had less than great TWR due to its intended purpose and huge amounts of avionics. (Also the aforementioned WVR losses)

 

I also didn't realize the divertless intakes were that detrimental to performance but it makes sense.

As Sweep mentioned, the F-35 has alot of volume in fuel. Just to put it in perspective, the F-35A carries 18,000 lb which is near the empty total weight of an early block f-16.

[wilky510]

I call BS on it as well. I don't have hard numbers but I can't fathom how a slick F-35 could possibly have a lower DI than a slick Viper. Add that to the fact that the F-35 has a lower TWR (allegedly) and the laws of physics tell you that the Viper wins the TTC to 10k competition every time.

You're probably right for a slick Viper. But a slicked Viper isn't going to win you many war competitions, unless it's guns only :D.

 

I think a guy over at F-16.net said (and proved with calculations, i believe) the F-35 out accelerates the Su-27 in subsonic regime, but i could be mistaken, Garrya might know.

[proletariat23]

was listening to an armed forces podcast, they had ed dames, he is famous for the stargate project- his quote in regards to the f-35.

 

" problem with that jet is information- too much of it- this thing was supposed to be secret well into generation 5. Low radar profile logistics have reached PROLIFERATION."

 

"how do you mean it's main problem is information?"

 

"well if you buy and pay for a really sharp knife, your enemy has to as well."

 

he went on;

 

"sun tsu said always leave a path to retreat, or your enemy will fight to the death- your sharpest knife should not be obvious, and when it's edge is needed, everyone who sees it needs to be,well, pacified."

 

"interesting"

 

This is my favorite part though Ed dames asked him "why do you think we have such a thing as secret weapons?"

 

"to keep our tech classified"

 

"wrong- if your enemy knows your ability will inevitably destroy him, they will toil into mania, bankruptcy, and perhaps even statelessness trying to cope."

 

caravan to midnight

[garrya]

I also didn't realize the divertless intakes were that detrimental to performance but it makes sense.

 

It depending on what flight regime is the most important for you. For subsonic regime where most dogfight happen , a variable inlet is pointless. Moreover, DSI is better for signature

 

I think a guy over at F-16.net said (and proved with calculations, i believe) the F-35 out accelerates the Su-27 in subsonic regime, but i could be mistaken, Garrya might know.

From this http://www.f-16.net/forum/viewtopic.php?f=55&t=52510 topic

[Hummingbird]

Induced drag plays minimal role when the speed is supersonic

 

It still plays a role, so saying that weight has no effect on top speed isn't true at all.

 

The weight also has a big effect on acceleration due to the Cdi alone.

Edited March 5, 2017 by Hummingbird

[garrya]

It still plays a role, so saying that weight has no effect on top speed isn't true at all.

 

The weight also has a big effect on acceleration due to the Cdi alone.

 

I didn't said weight, i said T/W ratio. Nevertheless, the roles is so small that you simply cant look at thrust/ weight of fighter and decide which will go faster.

[Rangi]

F-35B firing it's gun pod, in flight, for the first time and some interesting information on a proposed multi mission pod

http://www.thedrive.com/the-war-zone/8124/check-out-this-pic-of-an-f-35b-firing-its-gun-pod-in-the-air-for-the-first-time

 

https://www.terma.com/press/news-2012/f-35-multi-mission-pod-on-display/

[NineLine]

https://theaviationist.com/2017/03/08/meet-the-first-female-f-35-pilot/

 

[Rangi]

Does anyone know if they have lifted the weight restrictions for pilots? Of course this didn't come to my mind because of the previous video posted....

[Darkbrotherhood7]

Does anyone know if they have lifted the weight restrictions for pilots? Of course this didn't come to my mind because of the previous video posted....

 

It will be done in April.

 

The temporary change was implemented by the Air Force from concerns about ejection seat performance in specific areas of the aircraft’s flight performance envelope. The Air Force and Martin-Baker have subsequently published that the weight restriction will be lifted in April 2017

 

https://theaviationist.com/2017/03/08/meet-the-first-female-f-35-pilot/

[Shaniaxx]

Aviation Week Editors Jen DiMascio, Lara Seligman and Graham Warwick talk with Marine Lt. Col. David Berke. The team at Aviation Week has reported on the F-35 program for years from a programmatic and technical perspective. But Berke, who has flown the F-22, the F-35 and the F-18, tells them why the F-35 is a superior aircraft.

 

http://aviationweek.com/defense/podcast-view-cockpit-what-f-35-can-do

[Emu]

The F-35 has hit another snag — this time because it is just too good

• • Aug. 1, 2016, 5:13 PM
    

   

  The F-35 has hit yet another snag. During a recent exercise at Mountain Home Air Force Base in Idaho, US Air Force F-35A pilots set out to practice evading surface-to-air missiles, but they could not, because the SAM radars on the ground could not even find the ultra-stealthy planes.

   

  "If they never saw us, they couldn't target us," said Lt. Col. George Watkins, commander of the 34th Fighter Squadron at Hill Air Force Base, Utah, told the Air Force Times.

   

  To participate in the exercise as planned, the F-35As had to turn on their transponders, essentially announcing their presence so the SAM sites could see and engage them.

   

  "We basically told them where we were at and said, 'Hey, try to shoot at us,'" said Watkins.

   

  Had Watkins and crew not turned on their transponders, "most likely we would not have suffered a single loss from any SAM threats while we were training at Mountain Home."

   

  Air Force planners have been counting on the F-35's ability to enter heavily contested airspaceunseen by enemy radar and missiles, and the result of this exercise seems to vindicate that strategy, to say the least.

   

  A Patriot Air and Missile Defense launcher fires an interceptor during a previous test at White Sands Missile Range in New Mexico. The latest configuration of the system, called PDB-8, has passed four flight tests and is now with the US Army for a final evaluation. Raytheon

   

  "When we go to train, it's really an unfair fight for the guys who are simulating the adversaries," Watkins continued. "We've been amazed by what we can do when we go up against fourth-gen adversaries in our training environment, in the air and on the ground."

   

  The idea that F-35s can enter the most heavily defended air spaces on earth, pass by undetected by SAM sites and radars, and soften up those targets as well as legacy fighters represents the entire reasoning behind the trillion-dollar thrust to get this weapons system in the air.

   

  Watkins said that with just four F-35s, he can "be everywhere and nowhere at the same time because we can cover so much ground with our sensors, so much ground and so much airspace. And the F-15s or F-16s, or whoever is simulating an adversary or red air threat, they have no idea where we're at and they can't see us and they can't target us."

   

  The fourth US Air Force F-35A Lightning II aircraft arrives at the 422nd Test and Evaluation Squadron at Nellis Air Force Base, Nevada, in 2013. Reuters

   

  Watkins described a "pretty awesome feeling" seeing the grand plans of the F-35 come to fruition in a realistic training exercise, by rendering virtually all other platforms obsolete.

   

  Utah's Hill Air Force Base, where Watkins commands the squadron of F-35s, now has 21 certified pilots, 222 maintainers, and 15 F-35s at the ready. Another F-35 is scheduled to be delivered at the end of August, and more pilots and maintainers are continually being trained to full readiness.

   

  According to the Air Force Times, no further shortfalls in supply are expected, and top Air Force brass should declare the plane operationally ready within a few days.

[proletariat23]

and to think, it's basically built with 4+ and 5g tech, and we've had the 6th and 7g concepts in skunk since the early to mid 80's...

 

Have fun sa 5000.

[Hummingbird]

and to think, it's basically built with 4+ and 5g tech, and we've had the 6th and 7g concepts in skunk since the early to mid 80's...

 

Have fun sa 5000.

 

??

[probad]

so wrong on so many levels smh

 

in other news f-35 price keeps going down, projected $80m -a model for fy2019.

Edited March 19, 2017 by probad

[Emu]

and to think, it's basically built with 4+ and 5g tech, and we've had the 6th and 7g concepts in skunk since the early to mid 80's...

Oh... and what processors were they running on/designed with?