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-   -   The F-35 thread, Mk II (https://www.pprune.org/military-aviation/630295-f-35-thread-mk-ii.html)

ORAC 26th Apr 2020 21:49

My apologies, you are correct.

Adding the figures above to the original kpp acceleration requirements gives the following transonic acceleration times from M0.8 to M1.2 at 35K:

F-35A: 63 seconds.

F-35B: 81 seconds.

F-35C: 118 seconds.

The source of the above does note that that the A and B figures above beat all configurations of the F-16, and the C about half.

I’d post a link but it has a bl*gspot in the URL.


https://cimg5.ibsrv.net/gimg/pprune....0245056c0.jpeg

Which does remind me the F-35 was designed as a bomb truck with essentially the same dynamic performance as the F16 as a cheap to operate replacement. Accepting that it is rarely expected ever to go supersonic, I can see where limiting the envelope is a cost effective saving.

Dubious about the explanation for not addressing the hydraulic system issue though. It hasn’t blown a tyre in the wheel bay so far so we don't have to worry about it?

gums 26th Apr 2020 23:52

Salute!

So we finally get real numbers. The 8 seconds was an increase in the time to go from "x" to "y", and not total time to get there.. Whew. And sounds reasonable for a one gee st-and-level profile. Actually, total time sounds a bit weak, but whatthehell. I wanna see the actual configuration. Most of us did not sit there on AP and wait, but bunted over slightly and zoom. Once above the big drag hump, climbing at 1.2M or so was comfortable. But we never did it! We did not practice zipping in above the mach.

I never flew a Viper with a drag index of greater than 150 to my knowledge. Best I recall was at Red Flag with two x drops, centerline ECM pod, 6 x MK-82 and two by AIM-9L. Would have to look up what that DI was. I cruised most of the way in at 480 KCAS , but 540 for the final run-in. Burning about 9,000 pounds per hour at 90% power, and had a bit over 9,000 pounds of gas when approaching the IP for the bomb run.

I am not all that sure that the JSF concept back in early 90's was for a cheap bomb truck to replace the Viper. Seems to me it was to be the eventual replacement for the Hornet, Harrier and Viper. But stealthy. So the Harrier aspects meant less commonality, but what the hell. I am also not that sure the air superiority mission was a big driver. That is 'cause USAF was fighting like hell to build more Raptors, and a good way to cut the procurement was to tout the Stubbie as a great interceptor. Reminds me of the Viper versus the Eagle, where they wouldn't let us be capable of a BVR missile. Good topic someplace else.

The biggest change in the F-35/JSF development that I saw involved the advanced avionics compared to the initial requirements. I feel that the super duper avionics added a healthy 5 years from contract award thru development and finally an operational jet on the ramp at Hill AFB. And from all the folks I have talked with and available data, the machine is in a class by itself.

Aerodynamically, it does things like the Hornet and Migs/SU's. But it's major attributes bringing to the fight are LO and unbelieveable avionics. Its radar can be used as a jammer, as well as Wild Weasel enema threat detection system. Its ground map capability is amazing. Of course, it can zoom in and not use the radar except in a passive mode and exploit the 360 deg coverage in various E-O wavelengths.

Finally, having a hydraulic line bust from debris when a tire blows is not rare. The gear on a smaller plane is not like you see on a 787, or AB 330. Things are smaller and closer together. As long as you don't lose the other side or both hydraulic systems or NSW steering, no biggie.

Gums sends...




ORAC 27th Apr 2020 08:03

Configuration quoted was clean, internal AA Mx load.

The hydraulic line issue is that both lines run alongside each other and anything that cuts one is liable to also cut the second. They solved the issue by rerouting one of the lines on the C, but were unable to adopt the same solution on the A and B and have decided to live with the risk.

typerated 27th Apr 2020 09:31

Gums - I don't think the question is will the 35 do a job - but more is it all it could have been?

I think the A and C model have been seriously aerodynamically compromised by the VSTOL B model. - think the very wide shoulders for the lift fan and the wave drag that implies.
The lack of acceleration is a result of this.

I think the 35 was supposed to be a bit of everything to everyone - and now kind of hides as a attack aircraft with limited A2A.

Partly this is from the US services eroding their great position in the 80s - with a very capable high low mix

USAF F-15 and F-16
and USN F-14 and F/A-18

But the USAF didn't get enough F-22 to replace the eagles - so now the F-35 has to take up more slack as the lo part of the mix

and the USN have never replaced the F-14 so they are going to field to aircraft that are essentially both the low mix - F-18E and F-35.

Yes there are lots of good gizmos on the F-35 (expensive and late they may be) but what if you had fitted them on your A-7 instead?
How much worse would that have been than the F-35?

I certainly think the avionics could have been fitted to a better airframe (not compromised by a VSTOL model) and ended with a better and cheaper result.

And certainly the cheap economy of scale hasn't delivered with the F-35.



golder 27th Apr 2020 12:25


Originally Posted by ORAC (Post 10764540)
Configuration quoted was clean, internal AA Mx load.

You might want to double check that requirement. From memory it was with 2x AIM-120 and 2X 2k bombs. Some specs are with 60% fuel and 2 x AIM-120 only

Lonewolf_50 27th Apr 2020 14:51


Originally Posted by typerated (Post 10764632)
Gums - I don't think the question is will the 35 do a job - but more is it all it could have been?

It could never have been anything more than a compromise, given the political requirements behind the "Joint" Strike Fighter concept. F-22 is ample evidence of that. But it is well to remember that the original F-22 buy was much larger, but for reasons that still get my blood pressure up, the F-22 buy was curtailed. That was the air superiority fighter to replace the F-15.

Given the thrashing about that was the roles and missions fight after Desert Storm, F-35 was the politically acceptable way to move forward while achieving alleged "savings" by using a "common design."
Another way of looking at this is that what could be expected, and what we got, was well foreshadowed by the F-111 clusterfkuc.

golder 27th Apr 2020 15:24

"I think the 35 was supposed to be a bit of everything to everyone - and now kind of hides as a attack aircraft with limited A2A."

Is this the same F-35 that had a LER of 20:1 at the 2019 red air?

typerated 27th Apr 2020 22:11


Originally Posted by golder (Post 10765016)
"I think the 35 was supposed to be a bit of everything to everyone - and now kind of hides as a attack aircraft with limited A2A."

Is this the same F-35 that had a LER of 20:1 at the 2019 red air?

Take your point but I'd suggest there is a difference between sniping against packages on the Flag and being an air superiority fighter.

Somewhere in the MK1 thread were pages about a modeling study of the Chinese numbers taking advantage of the F-35's lack of pace and lack of shots.



gums 27th Apr 2020 23:45

Salute!

The Red and Green Flag exercises are the largest bunch of planes in the air at one time since Desert Storm, and they "scaled" to get some semblance of reality. In truth, the mass gaggles we flew in Linebacker II in 1972 had about the same number of airframes as what I saw in 1984. The adversary A2A threat in 'nam was not the biggie, and I can guess that PVNAF(?) only put up two dozen Migs on any of our day's strike package. Hell, they knew our times and routes from years of experience, and we could only throw in a few wrinkles. We still lost more planes than we should have, but we learned.

What Red Flag does, and did when I was there, is give a huge advatage to the RED by their ability to re-generate in mid-air, not have their bases attacked by cruise missiles or B-2's, no attacks on their supply lines, etc. that could limit their later days. Just think about that? Maybe the "flag" scenarios today use first day results for the next day, but I haven't heard about that. Up to me, I would have a 5 or 6 day event and have cumulative losses and get the logistics folks, back shop folks, airlift folks, refueling folks, etc. more involved.

In DS, the other guys had trouble just getting their planes off the ground when the horses came outta the gates. So maybe on day one, hour one or so, we see this giant air battle with 200 hundred planes heading one way and maybe 120 headed the other. One gaggle can see the other way out there, and the other cannot. Many missiles in the air, but few kills until they get closer. Could be a good theme for a techno-thriller, huh?

Good discussion fodder for another thread, huh, regardless of the F-35 whines?

Gums sends..


golder 28th Apr 2020 02:12


Originally Posted by typerated (Post 10765314)
Take your point but I'd suggest there is a difference between sniping against packages on the Flag and being an air superiority fighter.

Somewhere in the MK1 thread were pages about a modeling study of the Chinese numbers taking advantage of the F-35's lack of pace and lack of shots.

That sounds like the Stillion, RepSim and APA powerpoint. That used RANDS name and got Stillion sacked. I would look further into the F-35 and the systems it works in. Other than the F-22, there is currently nothing else out there.

Asturias56 28th Apr 2020 09:01

I though the real issue with the ship-bourne F-35 is lack of range - the knock-on effect being you need to move the CVN's closer into land......

golder 28th Apr 2020 09:17


Originally Posted by Asturias56 (Post 10765640)
I though the real issue with the ship-bourne F-35 is lack of range - the knock-on effect being you need to move the CVN's closer into land......

If that was the case, there would be a push for drop tanks in block 3. There are 2x 5,000 lb wet points,
Also the USN uses A2A tanker and buddy refueling. It is also going to continue to fly with the fa-18's, which block III with CFT. Will put it on a similar mission radius as the f-35c on internal fuel.

gums 28th Apr 2020 16:37

Salute!

post may have been mod review, so later response re: range later

This new attack jet has better range numbers than the Bug or Super Bug and won't be seen by enema radar until it's too late

Gums sends....

GlobalNav 28th Apr 2020 19:18


Originally Posted by Lonewolf_50 (Post 10764982)
It could never have been anything more than a compromise, given the political requirements behind the "Joint" Strike Fighter concept. F-22 is ample evidence of that. But it is well to remember that the original F-22 buy was much larger, but for reasons that still get my blood pressure up, the F-22 buy was curtailed. That was the air superiority fighter to replace the F-15.

Given the thrashing about that was the roles and missions fight after Desert Storm, F-35 was the politically acceptable way to move forward while achieving alleged "savings" by using a "common design."
Another way of looking at this is that what could be expected, and what we got, was well foreshadowed by the F-111 clusterfkuc.

It was such a foolish waste of billions of R&D to limit the F-22 acquisition for the sake of the "cheaper" F-35. We should have amortized that investment with several hundreds of F-22.

gums 28th Apr 2020 20:14

Salute!

I do not tink the F-22 cut was strictly to get the F-35. The JSF program was not nearly as significant on the international sales aspect as the "sale of the century" was in 1975. The administration of the 90's was not a big proponent of keeping the military very strong and capable. BFD. And then we had 9/11.

Back in mid-90's, USAF, USN,USMC and a NATO country or two knew they would need a new airframe in ten years, knew the acquisition process would be that long. Two U.S. administrations After 9/11 chose to spend $$$ on other stuff and then a never-ending deployment of forces to the mideast.

From talking with high-ranking folks in USAF back then, I go with the cuts by the administration of the 90's and not them trying to make room for the JSF.

I am not a fan of the one size fits all aspect of a new plane, but there have been a coupla successes between services and countries.

Back to the range of the new plane versus legasy attack platforms. New post to ensure I am not moded out.

Gums sends...



gums 28th Apr 2020 21:43

Salute!

A second range post due to 'net problems or a mod deletion.

If you can find an attack jet nowadays that launches from a carrier and flies 600 N.M. out, hits a tgt, and returns without needing to hit a tanker, be my guest. Even the Intruder and Sluf would have trouble competing, and both would be visible on enema radar a hundred or more n.m. from feet dry or the enema task force IAD ring of ships plus CAP planes. The Hornet, aka "Bug", would need gas about 30 minutes from lurch and then maybe coming home, plus having the radar visibility problems. That thing is about as bad as the Double Ugly for fuel consumption, and has been since I first met a Bug pilot at Hill in the mid-80's.

The new jet has great range numbers compared to previous jets, and most of us would take it right now, sight unseen.

Gums sends...








golder 28th Apr 2020 23:42

The Berlin wall marked the downfall of many programs. Even the eurofighter was put on the backburner and delayed for years. Water under the bridge, I think a clean sheet and start again would have been better. Now there is an EU division in the Euro 5th gen. With Germany and UK going their own way. A division of development money, that all are going to find hard.

As well as eating a lot of money. The ME isn't peer and even the obsolete gunned A-10 gets a run. We will need for China to get its act together. Before it kicks off in the pacific and real money is spent on platforms. Australia is trying to get an across the board modernisation, by 2030's. That's without looking at what it will be like after covid. That could be another can of worms.

Asturias56 29th Apr 2020 07:22

Gums

I agree about the current situation but it seems perverse to have a fleet of jets whose lack of range means either you have to invest in tanking (and where are the specialist tankers?) or you have to put your base closer to the enemy shores just at the time when they are developing long (-er) range anti ship missiles.

Stealth is all very fine but you still need to actually reach the enemy.

flighthappens 29th Apr 2020 07:24


Originally Posted by Asturias56 (Post 10766784)
Gums

I agree about the current situation but it seems perverse to have a fleet of jets whose lack of range means either you have to invest in tanking (and where are the specialist tankers?) or you have to put your base closer to the enemy shores just at the time when they are developing long (-er) range anti ship missiles.

Stealth is all very fine but you still need to actually reach the enemy.

you could have the B model...

golder 29th Apr 2020 09:43

Asturias from Italy, does have the B model. The legs on the f-35c is fine. I think it's something he heard, than what he read from a USN briefing.

Mind you, they do get good range out of this



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