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

gums 26th Mar 2020 18:48

Salute!

Yep, Jinda.

If you actually have to go to war without some pissant system that is not essential to deliver ordnance, navigate to a target, takeoff and land, etc., then I don't have a problem with declaring the plane "operational"

We always had to "fess up" about the FMC ( full mission capable) numbers of the Viper when I was the Ops Plans weenie for the first unit in the world. As with all new systems, we had our growing pains. And we identified the weak sisters early, then got help or a new vendor for the system/component.

In the Sluf I flew previously to the Viper, I was also in the first "operational" wing at The Beach. Iit was common to have a blank panel where the projected map display was or the ground map radar CRT ( the pencil beam radar function that gave tgt range in the dive toss mode did not need a steenkeeng CRT display). We also had a backup/aux UHF that didn't matter for most missions. Oh yeah, how about our doppler that helped the inertial? You could fly 99% of your missions without that thing and still have a 15 meter CEP.

My feeling is there are many trying to find anything they can to keep another platform active or in production, or just don't like this new jet. Our U.S. congress had one Warthog stalwart that was very influential. And then the female Hawg driver from the same state. The first was living in a CAS world that existed in the 60's, the one I had 400 missions in. The latter has more current experience, but never flew the types of missions I did or have the same avionics we had before she was even in kindergarden. I respect the combat experience above all, but sooner or later you have to move on to meet the new envisioned threat.

Gums sends...


ORAC 1st Apr 2020 20:56

https://breakingdefense.com/2020/03/...of-f-35-fleet/

USMC Debates Size and Future of F-35B Fleet

WASHINGTON: : The Marine Corps’ inability to recruit enough pilots has led the commandant to question the F-35’s place in the already budget-constrained Corps’ future plans, a potentially huge shift for the service that first fielded the Joint Strike Fighter and fought harder than any other service to build it and buy it.

“Our continued inability to build and sustain an adequate inventory of F-35 pilots leads me to conclude that we must be pragmatic regarding our ability to support” the program,” Gen. David Berger says in a blunt new 10-year force design plan. He calls for an external assessment of the aircraft’s place within the service relative to what he’s being asked to do in the National Defense Strategy and the forthcoming Joint Warfighting Concept, a document the Joint Staff is expected to wrap up later this year.

Berger not only singles out pilot shortfalls, but also notes high costs of maintaining and flying the F-35B as factors he’s weighing “in reconciling the growing disparity between numbers of platforms and numbers of aircrew.” The general has been very clear he does not expect his annual budgets to grow at any point in the near future, suggesting the best case scenario is that they remain flat as he wrestles with fleets of aging planes, helicopters and vehicles which grow increasingly costly to maintain........



Less Hair 2nd Apr 2020 13:46

USMC wants different stuff but their budget is set to remain the same. So they have to trade in things. Picking the most expensive ones to be chopped for new drones and bots.

sandiego89 2nd Apr 2020 14:21

Having the US Marines operate the C version is the things makes the least sense to me. Seems they wanted the Marines to operate a few C squadrons (and the first just became operational) to make up for gaps in carrier based US Navy squadrons.

Have the Marine focus on the B and get them some Super Hornets for conventional aviation.

gums 2nd Apr 2020 17:52

Salute!

Hate tellya, sandiego, but the Super Bug doesn't hold a candle to the "C" Stubbie in terms of range or ordnance delivery accuracy or A2A capability, and there's some "interoperability" aspects of the USMC having Stubbies replace their Bugs. Operating from the boats with the same jet as the USN simplifies logistics as well as basic operating procedures.

In WW2 the USMC flew off the USN boats as well as land strips. And that tradition has continued to this day. The Harrier changed things to some extent, because the USMC could operate off of austere fields that were not possible before. In 'nam, they had to install arresting gear on some fields so they could use their Scooters and Double Uglies other than at Da Nang, Cam Rahn, etc.

The USMC still insists on the ability to operate from austere fields to provide the support of their grunts. The F-35 satisfies that requirement.

The agreement to buy some Cee models makes the overall budget to the U.S. Congress more palitable, and is not a major change from using the Super Bug and Harriers.

Gums sends...




typerated 3rd Apr 2020 06:19

Frustrating there are less B models planned now. As making a common machine that can VSTOL has (severely) compromised the A and C models.
Think the thick shoulders for the lift fan placement and the induced drag that brings.

Much better in the first place to have designed a Superior conventional and carrier machine - and, designed as a separate machine for the Marines a Harrier 3.

But here we are.


Asturias56 3rd Apr 2020 07:14

Problem is Type that a "conventional" airframe means every Navy has to buy a conventional carrier...... and they are very very expensive. A "Harrier 3" would either look like the F-35 B (so no savings at all). or like a Harrier - in which case you'd be telling people like the USMC they had to go into action in (say) 2040, with a basic design that's very old and probably very easy to shoot down.

flighthappens 3rd Apr 2020 07:29


Originally Posted by Asturias56 (Post 10737753)
Problem is Type that a "conventional" airframe means every Navy has to buy a conventional carrier...... and they are very very expensive. A "Harrier 3" would either look like the F-35 B (so no savings at all). or like a Harrier - in which case you'd be telling people like the USMC they had to go into action in (say) 2040, with a basic design that's very old and probably very easy to shoot down.

or modify the design to reduce commonality (post SWAT how much commonality is really there anyway ) and keep the mission systems the same.

the mission systems is where it’s going to get expensive over time.

typerated 3rd Apr 2020 07:59


Originally Posted by Asturias56 (Post 10737753)
Problem is Type that a "conventional" airframe means every Navy has to buy a conventional carrier...... and they are very very expensive. A "Harrier 3" would either look like the F-35 B (so no savings at all). or like a Harrier - in which case you'd be telling people like the USMC they had to go into action in (say) 2040, with a basic design that's very old and probably very easy to shoot down.

I disagree.

How many Navy's operate a Harrier at the moment and How many are upgrading to F-35B? 2/5 of bugger all
Apart from the RN - who wanted the C model anyway!!!

And that is worth seriously comprising the 1000s of conventional and carrier airframes so a few B can be built?
Don't think so.

And what makes you think a Harrier 3 would be vulnerable than any other non stealthy airframe? Super Hornet, Typhoon for example?

It was crazy that nobody quashed the Marine's wanting a VSTOL bomb truck as a separate model of a conventional long range, supersonic, stealthy strike fighter.

And now they don't want as many B's - FFS

Less Hair 3rd Apr 2020 08:52

The VTOL seriously compromised the other versions, drove the cost to new heights and still the carrier version had to be redeveloped in many aspects. So the single airframe approach didn't pay off this time.
Maybe just the software (radar, networking, sensors, armament) should be unified but not the airframes themselves for future projects?

Asturias56 3rd Apr 2020 09:59

"How many Navy's operate a Harrier at the moment and How many are upgrading to F-35B? 2/5 of bugger all Apart from the RN - who wanted the C model anyway!!!"

I tend to agree - although I'm sure it was the USMC requirement that drove the B version - LM wouldn't build a VSTOL for the RN

THE big mistake IMHO was confusing the "conventional long range (cough cough), supersonic, stealthy strike fighter." with a bomb truck to support littoral campaigns. But history is littered with "we can save money by getting this aircraft to do all these other tasks"

ORAC 3rd Apr 2020 10:33

If the RN had asked for conventional large carriers with conventional aircraft they wouldn’t have got them. In the same way they wouldn’t have got conventional carriers in the 1970s rather than “through deck cruisers”.

Ask for new VSTOL carriers to replace the Ark Royal class - but just bigger, because steel is cheap and they’re really just big empty boxes. Ask for JSF to replace the SHar because they’re wearing out - and the USA say they are going to be cheap. Then work up from there. The step to switch to the C and fit EMALS was screwed by BAe.....

Asturias56 3rd Apr 2020 16:30

yes - got greedy and told the truth about the costs - they should have said "of course we can do it.... " and waited until the only option was the F-35C to 'fess up

weemonkey 6th Apr 2020 10:43


Originally Posted by gums (Post 10729199)
Salute!

Yep, Jinda.

If you actually have to go to war without some pissant system that is not essential to deliver ordnance, navigate to a target, takeoff and land, etc., then I don't have a problem with declaring the plane "operational"

.

Hi gums

Of course your pre requisite is that the "pissant systems" were there in the first place....

stay safe.

wm

Arcanum 7th Apr 2020 20:18


Originally Posted by Asturias56 (Post 10738427)
yes - got greedy and told the truth about the costs - they should have said "of course we can do it.... " and waited until the only option was the F-35C to 'fess up

Perhaps the MRA4 cost overrun and cancellation in 2010 was still fresh in BAEs mind? Better to be paid for a completed pair of carriers, plus through life costs, than low-ball the CATOBAR cost and risk another cancellation when the overruns kick in.

The cost of the carriers remains controversial today, would they have survived in CATOBAR form with F35C?

West Coast 8th Apr 2020 00:56

Commandant is busy transforming the Marine Corps to fight the Chinese. He’ll either be spot on or make the Marine Corps irrelevant.

I know you don’t want to fight the last war, but there’s no solid indication the last war, or at least that type of war is over.

I watch with surprise at the speed he is transforming the Corps.

Asturias56 8th Apr 2020 09:18

"there’s no solid indication the last war, or at least that type of war is over."

The USMC really never needed all those tanks and strike aircraft if they'd been restricted to doing what they were good at and what they were originally designed for - littoral operations, not full time war fighting onshore miles in the interior. .

The Army and Air Force could easily have handled every big fight since Inchon.

It happened because they didn't want to be seen to be sitting out the fight - mainly because they're patriots and aggressive as hell but also because if they weren't in Afghanistan etc some people would claim they were irrelevant and they'd be cut back. So they finished up as a duplicate of the USN and USAF both role & equipment-wise.

Now they're being re-oriented back to what I guess you could call "core values"

Not_a_boffin 8th Apr 2020 10:00


Originally Posted by ORAC (Post 10738012)
If the RN had asked for conventional large carriers with conventional aircraft they wouldn’t have got them. In the same way they wouldn’t have got conventional carriers in the 1970s rather than “through deck cruisers”.

Ask for new VSTOL carriers to replace the Ark Royal class - but just bigger, because steel is cheap and they’re really just big empty boxes. Ask for JSF to replace the SHar because they’re wearing out - and the USA say they are going to be cheap. Then work up from there. The step to switch to the C and fit EMALS was screwed by BAe.....

If only all the independent (ie not RN) force level operational analysis conducted in the mid and late 90s hadn't said that :
1. Carriers were needed and
2. They needed to deliver a decent sortie count, which meant a decent number of aircraft, which meant they had to be of a certain size, which meant that CTOL configuration became an option

STOVL was always the baseline choice for a number of reasons, primarily to do with training burden and force size, together with the perceived risk of EMALS (immaturity) or steam (sustainability) catapults. CTOL was a fallback option because of the perceived performance risk of the B-variant, enabled by the size of the ship which was driven by deck park arrangement for reduced manning. It did have advantages in both variety of potential aircraft and MASC capability. For a brief period when the B looked in real trouble, it was a good option to have, given 1 and 2 above.

The brief CTOL switch and then reversion was made too late (by about 3 or 4 years) to make it affordable, although I'm reasonably sure that the ACA over-egged the conversion costs to make certain.

The total spent and budgetted to date on both QEC and F35B are still significantly less than that on Typhoon - moreso if one considers NPV.


pr00ne 8th Apr 2020 10:30

typerated,

"​​​​​​And what makes you think a Harrier 3 would be vulnerable than any other non stealthy airframe? Super Hornet, Typhoon for example?"

Because it would be much MUCH slower and much MUCH more non stealthy!

weemonkey 8th Apr 2020 12:48


Originally Posted by Not_a_boffin (Post 10743526)
If only all the independent (ie not RN) force level operational analysis conducted in the mid and late 90s hadn't said that :
1. Carriers were needed and
2. They needed to deliver a decent sortie count, which meant a decent number of aircraft, which meant they had to be of a certain size, which meant that CTOL configuration became an option

STOVL was always the baseline choice for a number of reasons, primarily to do with training burden and force size, together with the perceived risk of EMALS (immaturity) or steam (sustainability) catapults. CTOL was a fallback option because of the perceived performance risk of the B-variant, enabled by the size of the ship which was driven by deck park arrangement for reduced manning. It did have advantages in both variety of potential aircraft and MASC capability. For a brief period when the B looked in real trouble, it was a good option to have, given 1 and 2 above.

The brief CTOL switch and then reversion was made too late (by about 3 or 4 years) to make it affordable, although I'm reasonably sure that the ACA over-egged the conversion costs to make certain.

The total spent and budgetted to date on both QEC and F35B are still significantly less than that on Typhoon - moreso if one considers NPV.

hopefully the f35b program can drag itself up by the bootlaces then.

Asturias56 8th Apr 2020 13:12

"2. They needed to deliver a decent sortie count, which meant a decent number of aircraft, which meant they had to be of a certain size, which meant that CTOL configuration became an option"

Interesting - the RAND study "Future Aircraft Carrier Options" back in 2017 has some interesting illustrations of how the perceived threat drives the response which drives the sortie rate which drives Carrier size. This was a major factor in the design of the "Fords"

"Of particular note is the fact that a major impetus for development of a carrier capable of supporting a high SGR (Sortie Generation Rate) was the Navy’s experience in Desert Storm, in which distances were short and the target environment rich. In such a context, high SGR would enable the faster delivery of ordnance and possibly a shortening of the campaign.

Even in the current environment, there are operational scenarios in which high SGR would be highly desirable, with defense against a swarm of small boats being one notable example. There is a large number of targets; the major detection sensor is radar and visual; the ability to use standoff munitions is limited. DCA in an environment in which rapid expenditure of air–air munitions is expected might be another.

In recent experience, however, there has been little need for large numbers of short sorties and a larger emphasis on longer-range sorties in which such features as ability to tank, ability to provide organic EA, and ability to provide long-range battle-space awareness are particularly important. Having the ability to rapidly generate sorties is not a detractor, but it has been less important than other features, and, in either case, the ability of current platforms to provide this support has been more than sufficient."

Not_a_boffin 8th Apr 2020 18:24

Not at all sure how that is relevant - or indeed accurate.

From memory, the six US CVBG on Desert Storm spent a lot of their time in the Red Sea or off Oman, which was hardly a "short trip". Only Midway (?) ended up in the Persian Gulf, adjacent to KTO. The more "recent experience" would appear to refer to OEF where a CVBG sits in the IO and provides ATO lines over Afghanistan - not exactly an exemplar.

The UK requirement was set against a number of scenarios developed in the mid-90s and the SGR derived from them. From memory they didn't include a large amount of CAS (except for one specific scenario), nor were FIAC a particular driver. They did include some significant warfighting phases and remain (generically) relevant.

The point about larger decks is that up to a certain point you're driven by safe parking requirement, which is largely about package size. Beyond which you get to a slightly bigger deck that enables reduced manning for a fixed SGR or a better SGR for a given deck manning setup, because you're not constantly re-spotting for the next launch / recovery serial - it's a marginal effect. The UK teams all went to visit Navy Lakehurst and interacted with the guys doing what became the Ford flightdeck design to examine operating drivers.

ORAC 8th Apr 2020 21:08

That may be perfectly true NAB. But it’s not the justification they used to sell the large carrier size to the politicians........

https://www.pprune.org/military-avia...ml#post9130803

Not_a_boffin 8th Apr 2020 22:50


Originally Posted by ORAC (Post 10744199)
That may be perfectly true NAB. But it’s not the justification they used to sell the large carrier size to the politicians........

https://www.pprune.org/military-avia...ml#post9130803

In case you're not aware how it works, the funding comes from the EAC (as was, now IAC last time I was involved) and is discussed in classified session, where the detail of the OA and economics is outlined (or more precisely, the plethora of studies that support the OR dossier, now IGBC is summarised). Prior to endorsing the requirement (itself a joint process under DCDS(EC)) and approving funding. For the avoidance of doubt, the EAC/IAC is a joint body, not something the Navy, Army or Air Force just pitch up at and ask for some money cos they feel like it.

The HCDC is an unclassified forum at which various pollies get to air their various hobby horses. Detail is not something they do - hence the level of brief from the witnesses. By the way, the "they" you refer to (assuming you mean Blackham) is the joint DCDS(EC) post, so many thanks for pointing out it was a joint endorsement......

At all stages from the endorsement of the original ST(S) in 1997, inclusion in SDR98 and onwards, it was clear that carriers were required and that they needed to be carriers from the off, not just a helicopter carrier with some make do and mends like their predecessors. It's just that some have always struggled to understand that relatively simple point. Not least because they equate size with cost, which is often far from the case. The real money is spent in a very different place from the surface fleet and carriers.

weemonkey 8th Apr 2020 23:06

Very interesting nab thank you

LowObservable 11th Apr 2020 23:13

The answer to much of the above - including the prevalence of RVLs and the change in USMC requirements - is a matter of public record since 2010.

Hint: have you seen (live or on video) any public VL, other than on a steel deck or a NAVFAC-spec'd VL pad?

chopper2004 22nd Apr 2020 16:30

Eielson receives its first F-35A
 
The last frontier receives its first A model.

https://www.eielson.af.mil/News/Arti...-lightning-ii/

cheers

RAFEngO74to09 24th Apr 2020 20:22

Having had the first several shows of the 2020 Season cancelled, the USAF F-35A Demonstration Team put together this excellent display sequence video.

Go "BEO" !


gums 24th Apr 2020 22:36

Salute!

Thanks, Chopper. Great to see the Demons back in action.

Been following the Green Demons since 1971, when I reported to fly one of their planes at The Beach. Outstanding unit.

Flew one to Korat in October 1972 for Linebacker II, and had the oppo to fly the same plane back to the states in December 1975 when the U.S. exited that stoopid war. Was my claim to fame, as my flight was last one of fighter bombers to leave the whole damned war!

The 356th FS should be of interest to all the RAF folks here that seem to own the forum. We flew Mustangs of 9th Air Force, but under operational control of 8th AF - the 354th Fighter Group, which had highest A2A kills of any wing ( don't pay attention to the 4th roosters).

One pilot wrote a well known book about their experience - "Big Friend, Little Friend".

We also had the only fighter pilot in the ETO to be awarded the MoH.

Gums sends...

ORAC 25th Apr 2020 14:28

Marching Back to the 1950s...
 
Back to the days of the Hunter and, of course, the SHar......

https://www.defensenews.com/air/2020...sonic-flights/

The Pentagon will have to live with limits on F-35’s supersonic flights

WASHINGTON — An issue that risks damage to the F-35’s tail section if the aircraft needs to maintain supersonic speeds is not worth fixing and will instead be addressed by changing the operating parameters, the F-35 Joint Program Office told Defense News in a statement Friday.

The deficiency, first reported by Defense News in 2019, means that at extremely high altitudes, the U.S. Navy’s and Marine Corps’ versions of the F-35 jet can only fly at supersonic speeds for short bursts of time before there is a risk of structural damage and loss of stealth capability.

The problem may make it impossible for the Navy’s F-35C to conduct supersonic intercepts.

“This issue was closed on December 17, 2019 with no further actions and concurrence from the U.S. services,” the F-35 JPO statement read. “The [deficiency report] was closed under the category of ‘no plan to correct,’ which is used by the F-35 team when the operator value provided by a complete fix does not justify the estimated cost of that fix...........

Three other category 1 deficiencies have also been officially designated as “closed," meaning they have either been fixed or the performance of the aircraft is being accepted as is, the JPO reported.........

An issue created when the F-35A and F-35B blow a tire, which can result in a severed hydraulic line, will remain uncorrected, the JPO statement said, but it has not come up again since the program switched tires.

“The DR [deficiency report] was closed under the category of ‘no plan to correct’ based on the fact that the landing gear system design meets all F-35 safety standards,” the statement read. “Issues related to premature bursting of tires were resolved by tire design changes during early F-35 development and no instances of dual hydraulic system loss caused by a tire burst have ever been observed on an F-35.”.......

gums 25th Apr 2020 17:14

Salute!

Well, ORAC. big deal.
Not sure about your experience making intercepts at 1.3M or above, and ditto for combat experience. Profile is lacking on those details.
Unlike the Raptor spec that needed "supercruise", the Stubbie needed to have some supersonic capability, but not its primary A2A requirement.
I, too, was surprised about some of the complaints

the F-35 jet can only fly at supersonic speeds for short bursts of time before there is a risk of structural damage and loss of stealth capability, a problem that may make it impossible for the Navy’s F-35C to conduct supersonic intercepts.
That was in 2011!

Both deficiencies were first observed in late 2011 following flutter tests where the F-35B and F-35C both flew at speeds of Mach 1.3 and Mach 1.4.
Think newer RAM and such might be used now? And I have not seen one reference to "structural" damage.

Unlike the early Hornets, where areo forces on the twin tails caused actual damage. McAir had closed the slots on the LEX of the YF-17, and that resulted in increased buffet and forces on the vertical tails.

There are many who wish to keep the old and faithful birds around that they like or personally have not flown a combat mission in the last 30 years, or even ever.... I think of McCain and his support of the Warthog. Now we have the Hornet mafia. USAF loves its Vipers, but this new jet has all they want and more - ask a few.

The Stubbie can do its missions very well, even beyond what was expected. More misisons than the Raptor or the Rafale or the Tiffie or the brand "x" from some other places. It was never intended to zoom out at the speed of stink and shoot down some enema planes way up in the stratosphere.

I would take the testimomny of those that have flown it and also have flown the Gen 4 planes. Combat experience would be nice, but we haven't had the "luxury" that some of us had back in the 70's, 80's and 90's. Those of us back then had the chance to fly "cold war" iron, then the early computer jets, and then stealth machines.

The F-35 is doing well, considering its complexity ( something I balked about, and that still concerns me), but it looks to be a game changer in the actual arena.

Gums opines...

ORAC 25th Apr 2020 17:40


Well, ORAC. big deal.
Not sure about your experience making intercepts at 1.3M or above, and ditto for combat experience. Profile is lacking on those details.
Fighter Controller for nearly 25 years. Three main reasons I found essential for fighters going supersonic.

1. To get to the fight, whether to achieve a cut-off or in a tail chase.

2. To get out of a fight when bugging out.

3. To be able to trade speed for height either to ID a high flier or to achieve a snap-up.

Most important being number one.


India Four Two 25th Apr 2020 18:28


...this excellent display sequence video.
What's the pilot doing with his left hand at 3:38 during the "pedal turn"?

gums 25th Apr 2020 19:18

Salute!

Good points , ORAC.

Bugging out these days doesn't mean you have to be at 1.5 M for a minute. Even back in my day we only needed to gain 200 or 300 knots in 30 seconds and the bad guy could watch our 36 inch tail pipe turning into a dot. That's assuming his Atoll or Aphid or Archer wasn't chasing us. So the biggie is to be able to rapidly accelerate while staying outta the other guy's launch envelope. Tuff these days with the off-boresight capabilities, but still a great capability to have. Besides, the mach numbers in the spec are usually not related to time to get there from "x" mach. Our Vipers could reach 2.0M, but took us well over a minute from 0.6M or so, more if still loaded with missiles. OTOH, we got to 1.1M or thereabouts within 15 or 20 seconds in a shallow descent.

Speed for height trades seem to be something Frank Luke and Richenbacher and that Hun ace learned a hundred years ago. Guess some things remain true. Heh heh. Supersonic? Well, I'd take 0.85M and be able to climb at a 30 deg angle without losing energy than a very short high pitch and then the slow speed recovery.

The tail chase is passe nowadays, and it was literally that way when I flew interceptors in the 60's. I only wound up in a tail chase when the controller rolled me out cold. Our NORAD standard stern attack was based on 50 knots overtake and a coupla miles at 6. The folks here that were not controllers need to realize that it takes 6 minutes to gain a mile on that sucker when 10 knots faster. So around a minute at 50 knots for each mile. Up at 0.9M you need burner to get any overtake on a co-speed tgt, so supersonic is a requirement. I learned the hard way chasing a B-58 one night. So the secret is not to wind up in a tail chase.
On most A2A intercepts now, we see HO or beam geometry, so total speed not a biggie. Nice to have, but I prefer my extra 1,000 pounds of gas.

Anyway, the supersonic stuff seems to appeal to a few that have little recent operational or combat experience in the A2A arena. The acceleration for bugging out or for a maneuver to gain an advantage or survive is more important than 1.3M that requires 30 or 40 seconds full blower.

Gums opines...

golder 26th Apr 2020 03:15

Scraping away opinion and hand wringing in the article. They did some stuff afterwards. It hasn't happened again.
https://www.f35.com/news/detail/lock...news-reporting

Lockheed Martin Comments on Defense News Reporting


June 12, 2019
F-35B and F-35C Horizontal Tail Durability at Sustained Supersonic Flight


The F-35B and C deliver on all performance requirements. The potential for tailboom or horizontal tail damage during prolonged supersonic speeds was found in the highest extremes of flight testing conditions that are unlikely replicated in operational scenarios. In fact, there have been no cases of this issue occurring in the operational fleet. Additionally, this is not identified as a safety of flight concern.

We implemented a change to the coatings on the horizontal tails and tail boom beginning in Lot 8 that increases durability and resolves this concern. This update allows the F-35B and C to deliver on all performance requirements with no tail boom or horizontal tail damage concerns.


Just This Once... 26th Apr 2020 16:40

gums The modern-day supersonic requirement goes hand-in-glove with long-range AIM-120 tactics. Pre-AMRAAM I would have agreed with your thoughts.

flighthappens 26th Apr 2020 17:20


Originally Posted by Just This Once... (Post 10764023)
gums The modern-day supersonic requirement goes hand-in-glove with long-range AIM-120 tactics. Pre-AMRAAM I would have agreed with your thoughts.

Based on this link, there is not a limit on any variant up to 1.19

its really only a limitation if you want a sustained supersonic run at >1.2 for the B (goodbye endurance) or >1.3 for the C.

seems low priority to me.

ORAC 26th Apr 2020 18:05

The C would burn all its fuel getting to M1.3 to be fair, the transonic acceleration due to that thick wing is considerable.

(M0.8 to M1.2 takes 8 seconds for the A, 16 seconds for B and the C takes.... 43 seconds.)


gums 26th Apr 2020 18:50

Salute!

Maybe the RAF folks could visit the F-35 forums over at F-16.net, and see some of the discussion re: required operational capability requirements, test results, opinions and such.

The test profiles for the Stubbie were about as benign as with most planes since the P-36. Wind up turns, climb steps, acceleration profiles, etc. And they still do things like one gee st and level at max power to get the time to accelerate from "x" to "y". If this jet can go from 0.8 to 1.2 in 8 seconds while st and level, then it beats about every jet since the early F-104's in the 50's, and the F-101B' a few years later. I only flew three jets that were true supersonic designs, and even the Viper could not go thru the mach from 0.8M in a few seconds unless going down hill. The VooDoo back in its day was actually better than the Viper, and we could bunt over to a half a gee or so at 20K on a max burner climb and go thru the mach while still climbing thru 25K , then climb at 1.3M or so to over 50K. The Zipper folks have as good or better war stories, as do the RAF Lightning folks.

ORAC's observation about fuel is the biggie. Ask any Eagle, Viper, Hornet, Tiffie, Rafale, 'nado pilot how many seconds they flew supersonic in an engagement once past the merge. Getting to the fight or intercept is a different aspect of the scenario.

@ Once, my "supersonic to the intercept" thot was pre-Slammer. The Slammer gave us the capability to shoot way out there with little or no giant white plume like the Sparrow. We didn't need the speed. The intercept geometry might still make a supercruise capablility a player, but most engagements since the early days of VietNam were not the stereotypical stern conversions that ORAC is very familiar with. Read some of the Combat Tree stuff and the 1972 engagements using Teaball and such.

The modern A2A scenarios favor gaining and maintaining energy for the areodynamics, super situational awareness ( like the Stubbie has) and missiles that can be launched and hit from parameters we could not dream of back in the day.

So the supersonic stuff is passe except for the RAM that might need to be re-applied to keep the RCS down to the level of a house wren.

Gusm opines...

flighthappens 26th Apr 2020 19:37


Originally Posted by ORAC (Post 10764089)
The C would burn all its fuel getting to M1.3 to be fair, the transonic acceleration due to that thick wing is considerable.

(M0.8 to M1.2 takes 8 seconds for the A, 16 seconds for B and the C takes.... 43 seconds.)

those numbers are incorrect.

the numbers you have provided are how much they missed the mark on the Transonic acceleration KPP by. I apologise but I cannot find what the KPP called for.

8s from 0.8 to 1.2 would be insane, and I suspect most would think that 43 seconds for 0.8 to 1.2 is “okay”.


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