F-35 Cancelled, then what ?
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It's official!
F-35 is
"badASS"
there's even a video..
So it must be true.....
Question. What is the similarity between F-35 and Climate gate??
Ans. True believers will literally say and do anything for the "cause".....
"badASS"
there's even a video..
So it must be true.....
Question. What is the similarity between F-35 and Climate gate??
Ans. True believers will literally say and do anything for the "cause".....
Last edited by glad rag; 31st May 2015 at 22:03. Reason: ho hum.
Originally Posted by Engines
You'd be interested to know that for a typical air to air burst length, the Mauser puts more shells on target than the 25mm Gatling. All Gatlings take a while to get spun up). And the 25mm round, while very good, isn't as good as the 27mm. However, water under the bridge and all that.
Firing the Mauser air-to-air or air-to-ground is a death ray. I have had consistently good results with it in the F-3. The high muzzle velocity, the stable barrel and the virtually instant start are all excellent features that make it that way.
I used the 20mm Gatling on the F-4 as a podded gun (a-a and a-g) and in the F-15 (a-a). Apart from the harmonisation issues on the F-4, they were, essentially the same weapon, but with an amazing aiming system in the Eagle. Against benign targets, allowing for a relatively short spin-up time, the Gatling is sufficiently accurate. Maybe not the death ray, but I could hit targets with it.
Now the differences.
1500 rounds per minute in a single stream, 260g projectile. 6000 rounds per minute, probably half that weight. I would need to put, maybe, 3 rounds through a target to hurt it with the Mauser, I would probably need 5 with the 20mm Gatling. Against a benign target, a dart or a flag, I would probably achieve the required number of hits very easily with the Mauser.
Against a manoeuvring target, when my aircraft isn't necessarily at the ideal speed or attacking position (as I would have from an academic, training set-up) things are very different. I may not be able to track the target. If I can, it may not be the ideal QWI firing solution. It may be a raking pass. It may be a very high angle-off or even close to head-on. Under those circumstances the death ray would be great only if I can point it at the target accurately enough and long enough to hit it - a few times. Distance between rounds becomes a much more significant factor. And that is where the 6000 rpm becomes such a dominant issue. And in that situation one doesn't need to wait until the sighting solution is perfect, rather one opens fire early so the spin-up time is no longer a factor.
Who would use a rifle to hit a flying bird? I would choose a shotgun.
On paper, yes, the Mauser looks good. And it is an excellent weapon. Given the choice in the less benign environment of combat ops, I would be very happy with the Gatling.
Differences in calibre. Yes, hence more hits required for the Gatling and remember I have been talking 20mm, not 25. I once stood in the Royal Ordinance Factory's test range and watched the difference between 30mm HE Aden Cannon rounds at 1200 rpm and the Vulcan cannon. The destructive power of the Aden was incredible. The move to 25mm closes that gap hugely, especially at the higher rate of fire.
As I understand it there has been not a lot of if any trials of SRVL, rolling landing on the QEC class carriers
, this is necessary to enable a loaded F35B to return to the ship with weapons aboard.
Let us hope that the stresses of ski jump take off and rolling landing do not necessitate the F35D, an F35B with the heavier undercarriage of the F35C....
If "Engines" had written this post he would have been a bit more polite. But he's a bit more professional than I am, whereas I've just seen this stuff done and felt I ought to say something.
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No Hover
Yes I am aware that SRVL has been simulated, I am also aware that the landing of an F35C on a UK Carrier was simulated as a fait accompli, this was before it became apparent that there were problems with the hook catching a wire, since resolved. Something can be simulated with all the best inputs but it does not necessarily mean that the real aircraft will behave as the simulator suggests.
There was a discussion I think on here about the bring back weight for a Vertical Landing for an F35B and as I recall it did not allow much unused ordnance to return to the ship, implicitly this might mean having to drop say an unused Storm Shadow into the drink, yes when the interface has been done, also as far as I am aware the F35B is not cleared to use any external points at the moment so has at most been taking off and landing on USS Wasp with a full tank of fuel, 2 1,000 lb bombs and two AMRAAMs, not a particularly heavy load out.
As regards trials of SRVL, I think that you are confirming that as far as anyone is aware there have been no trials of this sort of landing on an area similar to that available on a QEC Carrier. My point was that as much of the flight control of the F35 is down to software, it would seem that, if I am correct, that the software for SRVL has yet to be tested on an actual development aircraft and implicitly therefore has not been released to the fleet.
Yes I am aware that SRVL has been simulated, I am also aware that the landing of an F35C on a UK Carrier was simulated as a fait accompli, this was before it became apparent that there were problems with the hook catching a wire, since resolved. Something can be simulated with all the best inputs but it does not necessarily mean that the real aircraft will behave as the simulator suggests.
There was a discussion I think on here about the bring back weight for a Vertical Landing for an F35B and as I recall it did not allow much unused ordnance to return to the ship, implicitly this might mean having to drop say an unused Storm Shadow into the drink, yes when the interface has been done, also as far as I am aware the F35B is not cleared to use any external points at the moment so has at most been taking off and landing on USS Wasp with a full tank of fuel, 2 1,000 lb bombs and two AMRAAMs, not a particularly heavy load out.
As regards trials of SRVL, I think that you are confirming that as far as anyone is aware there have been no trials of this sort of landing on an area similar to that available on a QEC Carrier. My point was that as much of the flight control of the F35 is down to software, it would seem that, if I am correct, that the software for SRVL has yet to be tested on an actual development aircraft and implicitly therefore has not been released to the fleet.
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PhilipG,
Perhaps I can help here. Two items - VL performance and SRVL control.
F-35B had a hard requirement to be able to land on a ship using a VL with a specified internal ordnance load (two 1000b bombs an two AMRAAMS - about 3,600 lbs) plus enough fuel for a 'wave off' and a go around, at night. That requirement was set against a US specified 'tropical day'. This was a Key Performance Parameter (KPP), so had to be met. And it was, once the programme had sorted out the aircraft's weight in around 2004-6.
The UK, who had originally signed up to the above requirement, then added a more demanding requirement, to be able to recover to a ship at higher temperatures and lower pressures, which equated to summer at the northern end of the Gulf. (ordnance load and fuel requirements unchanged) These conditions became known as the 'UK Hot Day'. SRVLs are the way to meet this requirement.
You might be surprised to learn that very few combat aircraft, land or sea based, are designed to be able to land with anything like a full ordnance load. The designers will assume a maximum landing weight which is always MUCH lower than the aircraft maximum all up weight (MAUW). Many current combat aircraft have to jettison stores or fuel to land on a ship (including cat and trap) and most land base combat aircraft have landing weight restrictions. As an example, the Tornado couldn't land at all with its JP233 weapons fitted.
F-35B has certainly been cleared for a variety of external hard points, but you are correct in that I've not seen any aircraft with pylons or stores doing VLs yet. I would guess that the Pax River team are working through the VL regime on these as we speak. Very extensive computer simulation, wind tunnel and scale model testing has been carried out on F-35B vertical landing aspects, and this will reduce the risks associated with such recoveries.
SRVL software - the aim of the programme was to use the existing flight control modes (and cockpit displays) as far as possible. Remember that SRVLs are a required manoeuvre for the USMC to short strips, and have been cleared for use in service. Work started on SRVL ship landing capability as far back as 2004, but the UK's indecision on F-35B/C procurement between 2010 and 2012 led to delays in the later stages of this work.
You're quite correct that it's not been tested on the ship yet, but as NoHover reasonably points out, the ship's not at sea yet. But it's certainly being developed and tested using both simulators and development (and production) aircraft. Same as the VLs - yes, risks exist until the final trials are carried out and release to service is granted. That's 'ops normal' for any aircraft's flight test/clearance programme.
Hope this helps a little,
Best Regards to those doing the testing,
Engines.
Perhaps I can help here. Two items - VL performance and SRVL control.
F-35B had a hard requirement to be able to land on a ship using a VL with a specified internal ordnance load (two 1000b bombs an two AMRAAMS - about 3,600 lbs) plus enough fuel for a 'wave off' and a go around, at night. That requirement was set against a US specified 'tropical day'. This was a Key Performance Parameter (KPP), so had to be met. And it was, once the programme had sorted out the aircraft's weight in around 2004-6.
The UK, who had originally signed up to the above requirement, then added a more demanding requirement, to be able to recover to a ship at higher temperatures and lower pressures, which equated to summer at the northern end of the Gulf. (ordnance load and fuel requirements unchanged) These conditions became known as the 'UK Hot Day'. SRVLs are the way to meet this requirement.
You might be surprised to learn that very few combat aircraft, land or sea based, are designed to be able to land with anything like a full ordnance load. The designers will assume a maximum landing weight which is always MUCH lower than the aircraft maximum all up weight (MAUW). Many current combat aircraft have to jettison stores or fuel to land on a ship (including cat and trap) and most land base combat aircraft have landing weight restrictions. As an example, the Tornado couldn't land at all with its JP233 weapons fitted.
F-35B has certainly been cleared for a variety of external hard points, but you are correct in that I've not seen any aircraft with pylons or stores doing VLs yet. I would guess that the Pax River team are working through the VL regime on these as we speak. Very extensive computer simulation, wind tunnel and scale model testing has been carried out on F-35B vertical landing aspects, and this will reduce the risks associated with such recoveries.
SRVL software - the aim of the programme was to use the existing flight control modes (and cockpit displays) as far as possible. Remember that SRVLs are a required manoeuvre for the USMC to short strips, and have been cleared for use in service. Work started on SRVL ship landing capability as far back as 2004, but the UK's indecision on F-35B/C procurement between 2010 and 2012 led to delays in the later stages of this work.
You're quite correct that it's not been tested on the ship yet, but as NoHover reasonably points out, the ship's not at sea yet. But it's certainly being developed and tested using both simulators and development (and production) aircraft. Same as the VLs - yes, risks exist until the final trials are carried out and release to service is granted. That's 'ops normal' for any aircraft's flight test/clearance programme.
Hope this helps a little,
Best Regards to those doing the testing,
Engines.
PhilipG,
I totally agree with you about simulation vs live trials and I was very interested in NoHoverstop's use of the phrase,
which seems a strange way to describe a simulation. They did a lot of hard sums on other stuff (helmet, 469 bulkhead, the engine, the hook, etc), but some of those didn't measure up when they tried them for real, in the real, non-digital world.
As things stand, it has long been widely acknowledged that SRVL will be the preferred recovery for improved bring back, but it doesn't come without limitations. I was challenged on this last week so I'll address a couple of them now. Deck space for landing at or above 60 kts. Stop other operations from the deck while SRVLs are undertaken. Sea state limits for SRVL, don't know what the limits are, but then who does yet?
That said, if you don't want to throw away your perfectly serviceable Storm Shadows, they will need to sort it out. As far as anyone can tell, they almost certainly will make it work.
As for trials on a QE sized carrier deck, like you, I have seen nothing on this yet. Indeed, the Marines are declaring that they will only do VLs on the smaller ships (yes, I know how big a GE is). But then they are having to accept IOC very soon with a lot of "acceptable" or, at least, "accepted" shortfalls. I gather they are referring to the missing bits finally arriving late as "upgrades" now, perhaps implying that they are making the jet even better.
End of ramble.
Edited to add: Just seen Engines' post. Yes, at this point the situation is very much "ops normal" with regard to this landing mode.
I totally agree with you about simulation vs live trials and I was very interested in NoHoverstop's use of the phrase,
Originally Posted by NoHoverstop
However SRVL has been done for real by a digital STOVL jet pretending to be an F-35B
As things stand, it has long been widely acknowledged that SRVL will be the preferred recovery for improved bring back, but it doesn't come without limitations. I was challenged on this last week so I'll address a couple of them now. Deck space for landing at or above 60 kts. Stop other operations from the deck while SRVLs are undertaken. Sea state limits for SRVL, don't know what the limits are, but then who does yet?
That said, if you don't want to throw away your perfectly serviceable Storm Shadows, they will need to sort it out. As far as anyone can tell, they almost certainly will make it work.
As for trials on a QE sized carrier deck, like you, I have seen nothing on this yet. Indeed, the Marines are declaring that they will only do VLs on the smaller ships (yes, I know how big a GE is). But then they are having to accept IOC very soon with a lot of "acceptable" or, at least, "accepted" shortfalls. I gather they are referring to the missing bits finally arriving late as "upgrades" now, perhaps implying that they are making the jet even better.
End of ramble.
Edited to add: Just seen Engines' post. Yes, at this point the situation is very much "ops normal" with regard to this landing mode.
Interesting backstory on the gun. At the time the switch to the Gatling was made, in 2003, LM was convinced they had weight margin to play with. They were also thinking of a mod that would have allowed the B to carry 2K JDAMs (which could probably have been recovered VL in temperate conditions and/or with daytime reserves). And the Gat was assessed as having lower life costs relative to adding a new caliber to the Navy/AF logistics system.
They took the decision and then found out about the weight. The F-35A now has that giant wart above the R/H inlet, the gun pod has about two bursts of ammo, and they need a new round anyway...
They took the decision and then found out about the weight. The F-35A now has that giant wart above the R/H inlet, the gun pod has about two bursts of ammo, and they need a new round anyway...
I totally agree with you about simulation vs live trials and I was very interested in NoHoverstop's use of the phrase,
Originally Posted by NoHoverstop
However SRVL has been done for real by a digital STOVL jet pretending to be an F-35B
which seems a strange way to describe a simulation.
Originally Posted by NoHoverstop
However SRVL has been done for real by a digital STOVL jet pretending to be an F-35B
which seems a strange way to describe a simulation.
Carrier trials prove JSF's rolling vertical landing concept - 7/4/2007 - Flight Global
I remain a bit puzzled.
If fitting on the Invincible was never a requirement for STOVL, then what did the UK Ambassador and the MoD and BAE Systems think that the RN would use?
And why were both Boeing and LM going to some pains to ensure that the aircraft would fit pretty much anywhere a Harrier did?
If fitting on the Invincible was never a requirement for STOVL, then what did the UK Ambassador and the MoD and BAE Systems think that the RN would use?
And why were both Boeing and LM going to some pains to ensure that the aircraft would fit pretty much anywhere a Harrier did?
Ecce Homo! Loquitur...
I totally agree with you about simulation vs live trials and I was very interested in NoHoverstop's use of the phrase,
Quote:
Originally Posted by NoHoverstop
However SRVL has been done for real by a digital STOVL jet pretending to be an F-35B
which seems a strange way to describe a simulation.
Quote:
Originally Posted by NoHoverstop
However SRVL has been done for real by a digital STOVL jet pretending to be an F-35B
which seems a strange way to describe a simulation.
WASP trial summary
A summary of the USS WASP trials completed:
Marine Corps F-35Bs depart USS Wasp after carrier tests - 5/30/2015 - Flight Global
-6 aircraft (maybe 7 from the earlier report of a spare flying out)
-10 pilots
-108 Sorties flown over a "week and a half"
-85.5 hours
-As a test. A spare engine flown out in a MV-22.
-Sounds like lots of software workd remains
Marine Corps F-35Bs depart USS Wasp after carrier tests - 5/30/2015 - Flight Global
-6 aircraft (maybe 7 from the earlier report of a spare flying out)
-10 pilots
-108 Sorties flown over a "week and a half"
-85.5 hours
-As a test. A spare engine flown out in a MV-22.
-Sounds like lots of software workd remains
I remain a bit puzzled.
If fitting on the Invincible was never a requirement for STOVL, then what did the UK Ambassador and the MoD and BAE Systems think that the RN would use?
And why were both Boeing and LM going to some pains to ensure that the aircraft would fit pretty much anywhere a Harrier did?
If fitting on the Invincible was never a requirement for STOVL, then what did the UK Ambassador and the MoD and BAE Systems think that the RN would use?
And why were both Boeing and LM going to some pains to ensure that the aircraft would fit pretty much anywhere a Harrier did?
Fitting anywhere a Harrier did might just describe the US LHDs....
As for the artists impression, they usually reach for the nearest available template - and the PR people that commission the work don't know any better.
Do a Hover - it avoids G
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However SRVL has been done for real by a digital STOVL jet pretending to be an F-35B
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LO,
I sincerely apologise if I've not been sufficiently clear over the way UK requirements influenced the design.
As I think I've already said, the UK's involvement at the early stages (CALF, JAST) was pretty limited. At that time, early studies were informed by the UK's NST 6466, which certainly did call for a replacement STOVL aircraft capable of operating from an Invincible class ship.
However, as nab points out, it soon became clear that getting a larger (over 50,000 lb) aircraft on a CVS was never going to be much of a starter. The requirements for the technical demonstration phase (the X-planes) were very generic, and didn't go into much detail. However, the USMC and made it plain that the new aircraft would be required to fit into roughly the same footprint as an AV-8B. That started setting STOVL size.
The only formal requirements for the F-35 were set out in the JORD, somewhere around 1998/1999/2000. You will remember (but others may not) that this was the culmination of around 5 years' requirements development, and a key piece of that process was making sure that it didn't contain any items that inadvertently lead the design into a bad place - your example of the TSR-2's massive landing gear, (driven by a strange requirement for soft field ops) is an excellent one. Anything before the JORD was general and indicative - the JORD was the document that nailed down exactly what the customers wanted.
By the time the JORD was being nailed down, the UK had already decided to go for CVF, but they were miles away from a defined ship. As a result, the UK decided to put in a minimal set of ship compatibility requirements that would not drive the aircraft anywhere strange. Thats why the requirements were set out in the way I explained in a previous post - 'compatibility with CVS flight deck and hangar layouts'. The folding wingtips for the F-35B were a scheme (not even a design) offered by LM for discussion with the UK - but they were turned down pretty smartly, as the UK had deliberately omitted reference to CVS lifts. Like I said, the UK MoD were terrified of applying additional national requirements that might affect weight and cost. They were by then aiming to design the ship around the aircraft.
On the gun, you're on the money - LM weren't paying very much attention to weight in around 2001, which was a major error for a powered lift aircraft programme. The through life cost estimates they used were skewed to show the Gatling in a good light, the Mauser in a bad light. But, as I've said, water under the bridge now.
Hope this helps,
Best regards as ever to those making the trials work,
Engines
I sincerely apologise if I've not been sufficiently clear over the way UK requirements influenced the design.
As I think I've already said, the UK's involvement at the early stages (CALF, JAST) was pretty limited. At that time, early studies were informed by the UK's NST 6466, which certainly did call for a replacement STOVL aircraft capable of operating from an Invincible class ship.
However, as nab points out, it soon became clear that getting a larger (over 50,000 lb) aircraft on a CVS was never going to be much of a starter. The requirements for the technical demonstration phase (the X-planes) were very generic, and didn't go into much detail. However, the USMC and made it plain that the new aircraft would be required to fit into roughly the same footprint as an AV-8B. That started setting STOVL size.
The only formal requirements for the F-35 were set out in the JORD, somewhere around 1998/1999/2000. You will remember (but others may not) that this was the culmination of around 5 years' requirements development, and a key piece of that process was making sure that it didn't contain any items that inadvertently lead the design into a bad place - your example of the TSR-2's massive landing gear, (driven by a strange requirement for soft field ops) is an excellent one. Anything before the JORD was general and indicative - the JORD was the document that nailed down exactly what the customers wanted.
By the time the JORD was being nailed down, the UK had already decided to go for CVF, but they were miles away from a defined ship. As a result, the UK decided to put in a minimal set of ship compatibility requirements that would not drive the aircraft anywhere strange. Thats why the requirements were set out in the way I explained in a previous post - 'compatibility with CVS flight deck and hangar layouts'. The folding wingtips for the F-35B were a scheme (not even a design) offered by LM for discussion with the UK - but they were turned down pretty smartly, as the UK had deliberately omitted reference to CVS lifts. Like I said, the UK MoD were terrified of applying additional national requirements that might affect weight and cost. They were by then aiming to design the ship around the aircraft.
On the gun, you're on the money - LM weren't paying very much attention to weight in around 2001, which was a major error for a powered lift aircraft programme. The through life cost estimates they used were skewed to show the Gatling in a good light, the Mauser in a bad light. But, as I've said, water under the bridge now.
Hope this helps,
Best regards as ever to those making the trials work,
Engines
...flight trials carried out using a Harrier, not F-35. So no F-35 handling characteristics, not the full F-35 system, not the F135 engine, not the 2015 software, not the F-35 brakes....
A Harrier trying to simulate an F-35? For proving a concept, fine. But that is still a simulation on a completely different airframe. The interest that raised the question, remember, was weather the F-35 had been tested on a QE sized deck.
Sorry, I should add it was proving for the Bedford Array, was it not?
A Harrier trying to simulate an F-35? For proving a concept, fine. But that is still a simulation on a completely different airframe. The interest that raised the question, remember, was weather the F-35 had been tested on a QE sized deck.
Sorry, I should add it was proving for the Bedford Array, was it not?
Last edited by Courtney Mil; 1st Jun 2015 at 16:50.
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Sorry, I should add it was proving for the Bedford Array, was it not?
Do a Hover - it avoids G
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Courtney
Sorry, my post clearly annoyed you. That was not my intention. I think everybody realises that the Yeovilton SRVL flying did not use an F135!
Moving on for those who may not be as familiar with FBW as you, I would point out that the handling characteristics of a FBW aircraft are those that are provided by the FBW system and not those of the aircraft’s aerodynamics. For example In circumstances where the Typhoon is longitudinally unstable aerodynamically it seems normally stable to the pilots thanks to the FBW.
So the SRVL pilots at Yeovilton were definitely looking at the chosen F35 ‘handling’ characteristics (pull the stick back to go up regardless of speed etc) but the software was dealing with Harrier aerodynamics. Mind you I guess at 70 odd kts there is not much V squared about so the different aerodynamics would not have been a huge deal.
Big rant coming about words used.
What does annoy me about this whole Shipboard Rolling Vertical Landing (SRVL) thing is that to the purist it is no such thing. An RVL is where you start from the hover and choose to step forward for the touchdown because of surface conditions. A Slow Landing (SL) is where you have to add wing lift to the vertical component of engine thrust in order to equal your weight. So these SRVLs are (will be) SSLs. Indeed when an RAE boffin introduced me to a new control system in 1954 he called it a Manoeuvre Demand system. How much more correct and informative than FBW.
Sorry, my post clearly annoyed you. That was not my intention. I think everybody realises that the Yeovilton SRVL flying did not use an F135!
Moving on for those who may not be as familiar with FBW as you, I would point out that the handling characteristics of a FBW aircraft are those that are provided by the FBW system and not those of the aircraft’s aerodynamics. For example In circumstances where the Typhoon is longitudinally unstable aerodynamically it seems normally stable to the pilots thanks to the FBW.
So the SRVL pilots at Yeovilton were definitely looking at the chosen F35 ‘handling’ characteristics (pull the stick back to go up regardless of speed etc) but the software was dealing with Harrier aerodynamics. Mind you I guess at 70 odd kts there is not much V squared about so the different aerodynamics would not have been a huge deal.
Big rant coming about words used.
What does annoy me about this whole Shipboard Rolling Vertical Landing (SRVL) thing is that to the purist it is no such thing. An RVL is where you start from the hover and choose to step forward for the touchdown because of surface conditions. A Slow Landing (SL) is where you have to add wing lift to the vertical component of engine thrust in order to equal your weight. So these SRVLs are (will be) SSLs. Indeed when an RAE boffin introduced me to a new control system in 1954 he called it a Manoeuvre Demand system. How much more correct and informative than FBW.
John, no, not annoyed, I was just making a point, somewhat bluntly, perhaps.
I do like your description to those not used to FBW. And even more the use of RVL. Let's face it, something is either vertical or it ain't. I guess the origin of the definition must come from whether it's the wing assisting the lift fan/nozzle or the other way round. In this case it is clearly not vertical.
I do like your description to those not used to FBW. And even more the use of RVL. Let's face it, something is either vertical or it ain't. I guess the origin of the definition must come from whether it's the wing assisting the lift fan/nozzle or the other way round. In this case it is clearly not vertical.