No cats and flaps ...... back to F35B?
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The other angle of this is La France - and the cooperation Treaty we signed with them last year on matters naval and nuclear. If we go back to Dave-B (and pls God, make this stupid idea stop) then La France is rather stuff-ed whenever Port-Avion CdG needs to be fixed.
So according to the last rumor I heard, Dave is getting it from Barack and from Sarko: Dude, don't do the stupid thing....!
S41
So according to the last rumor I heard, Dave is getting it from Barack and from Sarko: Dude, don't do the stupid thing....!
S41
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Quote:
Lockheed Martin started it by calling the F35 'Lightning'.
WW,
Simply that I associate 'Lightning' with something that arrives very, very quickly. F35 is, at a guess, 10 years away, maybe more, and some versions it seems may never arrive at all.
Lockheed Martin started it by calling the F35 'Lightning'.
What of it, if you don't mind me asking? 24th Mar 2012 17:38
Simply that I associate 'Lightning' with something that arrives very, very quickly. F35 is, at a guess, 10 years away, maybe more, and some versions it seems may never arrive at all.
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Don't shoot the messenger
Somebody told me that mixed up in this whole sorry B/C story is that the power supplies of the boat will have to be changed (whichever type of cat) and there is some concern about the modest top speed of the class as well.
Somebody told me that mixed up in this whole sorry B/C story is that the power supplies of the boat will have to be changed (whichever type of cat) and there is some concern about the modest top speed of the class as well.
Mr Boffin says that there enough volts to do the job. It needs software changes and cables. And a bloody great plug.
Therefor it is not without logic to think that it will draw its power for each shot from a buffer aka a set of capacitors, this would not require an overwhelmingly large dimentioned powercable from the generator to the capacitors, it'll probably have ample of loadtime (30-45 sec) to prepare for the next shot.
Therefor high peakpower from the generator is probably not required even with 2 (and in the case of the US NAVY 4) CAT's in constant use at its highest possible rate.
AKAIK the US NAVY CVN's must be able to launch 4 planes every 90 seconds at the least, but probably don't better 4 every minute which gives about 1 minute between every launch per CAT.
The current configuration is a bit more steampunk. The juice spins up a bank of seriously big-a55 motor-flywheel-generators which store energy kinetically. Throw switch, dump energy rapidly into cat. SHAZAM! Capacitors are under study, not ready for Ford or PoW.
As for the name Lightning - it reminds me of the scene in To The Manor Born where DeVere tells Audrey (Penelope Keith) that his new horse is named Fearless, and she responds:
"He's a coward. Horses are always named for the opposite of what they actually are. If you ever find a horse called Utter Rubbish, buy it."
Ms Keith was superb in The Good Life, too, but was always upstaged by the dynamic phenomena occurring in Felicity Kendal's shirts.
As for the name Lightning - it reminds me of the scene in To The Manor Born where DeVere tells Audrey (Penelope Keith) that his new horse is named Fearless, and she responds:
"He's a coward. Horses are always named for the opposite of what they actually are. If you ever find a horse called Utter Rubbish, buy it."
Ms Keith was superb in The Good Life, too, but was always upstaged by the dynamic phenomena occurring in Felicity Kendal's shirts.
Mmmmmm, Felicity Kendall........
Right - back to electrickery. The link below gives the details on the EMALS system.
Electromagnetic Aircraft Launch System (EMALS)
The main difference twixt the CVN78 fit and the QEC fit is that for CVN, you have a power generation grid that is separate from the propulsion system, ie the kettle generates electrical power via turbo-generators, but the main propulsion system is geared steam turbines. On QEC, the main engines (two Trent GTAs and 4 Wartsila diesels) generate electrickery (about 110MW) that powers both the ships propulsion system (four 20MW electric motors, scaled up from the T45 plant) and the ships service load. The only difference I can think of is that CVN probably distributes electrical power at 450V AC 60hz, which is what the "Prime Power Interface" will see, whereas QEC distributes shipwide at 11kV AC, but steps down to 440V 60hz for zonal power supplies.
I'm far from being an expert in electrickery, but would have thought that the PPI shouldn't be too difficult to modify to accept 440V. As noted previously, there will have to be work done on the QEC power management system, but it should only be accepting another pair of loads (cat 1 and cat 2) of some small MW. That will cause some balancing issues but nothing that shouldn't be possible to overcome.
As far as "convertible" goes, there appears to be a bit of a misunderstanding. The meaning of the term was always that if during the design, build or service life of QEC, the STOVL option became a non-starter or was superseded by a CTOL aircraft or UCAV, then the design of teh ship was such that cats n' traps could be accommodated. What this actually means is that there is enough space to accommodate cats, recovery deck and safe parking areas, there is enough spare volume in the gallery deck to fit cats n traps of whatever flavour and that there is sufficient weight provision in the stability and structural calculations. It was never intended that you could just plug and play - what it meant was that the ship was essentially capable of conversion without starting again.
IMO opinion the limited speed of QEC (which was one of the early performance trades) might have an impact, but not due to EMALS, more an operational issue when trying to recover aircraft with light winds from astern on the MLA. That basically means you have to turn away from your desired course and work up to a fair speed to have sufficient wind over deck for the cabs to land. You pays your money and takes your choice, it's a minor PITA, rather than a real showstopper.
Right - back to electrickery. The link below gives the details on the EMALS system.
Electromagnetic Aircraft Launch System (EMALS)
The main difference twixt the CVN78 fit and the QEC fit is that for CVN, you have a power generation grid that is separate from the propulsion system, ie the kettle generates electrical power via turbo-generators, but the main propulsion system is geared steam turbines. On QEC, the main engines (two Trent GTAs and 4 Wartsila diesels) generate electrickery (about 110MW) that powers both the ships propulsion system (four 20MW electric motors, scaled up from the T45 plant) and the ships service load. The only difference I can think of is that CVN probably distributes electrical power at 450V AC 60hz, which is what the "Prime Power Interface" will see, whereas QEC distributes shipwide at 11kV AC, but steps down to 440V 60hz for zonal power supplies.
I'm far from being an expert in electrickery, but would have thought that the PPI shouldn't be too difficult to modify to accept 440V. As noted previously, there will have to be work done on the QEC power management system, but it should only be accepting another pair of loads (cat 1 and cat 2) of some small MW. That will cause some balancing issues but nothing that shouldn't be possible to overcome.
As far as "convertible" goes, there appears to be a bit of a misunderstanding. The meaning of the term was always that if during the design, build or service life of QEC, the STOVL option became a non-starter or was superseded by a CTOL aircraft or UCAV, then the design of teh ship was such that cats n' traps could be accommodated. What this actually means is that there is enough space to accommodate cats, recovery deck and safe parking areas, there is enough spare volume in the gallery deck to fit cats n traps of whatever flavour and that there is sufficient weight provision in the stability and structural calculations. It was never intended that you could just plug and play - what it meant was that the ship was essentially capable of conversion without starting again.
IMO opinion the limited speed of QEC (which was one of the early performance trades) might have an impact, but not due to EMALS, more an operational issue when trying to recover aircraft with light winds from astern on the MLA. That basically means you have to turn away from your desired course and work up to a fair speed to have sufficient wind over deck for the cabs to land. You pays your money and takes your choice, it's a minor PITA, rather than a real showstopper.
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About the EMALS, I was just attempting a best guess how it is set up,
Capacitorbanks or flywheel as a buffer, it doesn't really matter I guess but still,
thx for clearing things up.
BTW, I'm certain that I've read somewhere ,over here or on the keypublishing
forums or somewhere else, that the speed of the carrier is supposed to be a lot less important for the use of the EMALS-CAT, even the heaviest planes at MTOW can take off with 0 wind over deck.
The more gradual acceleration and higher total power is supposed to make the EMALS superior in those regards vs the old C11 and C13 steam cat.
ALso the speed for landing is high enough for CDG to work with all its planes, also only 28-ish knots and that is even smaller than the future UK CVF.
Capacitorbanks or flywheel as a buffer, it doesn't really matter I guess but still,
thx for clearing things up.
BTW, I'm certain that I've read somewhere ,over here or on the keypublishing
forums or somewhere else, that the speed of the carrier is supposed to be a lot less important for the use of the EMALS-CAT, even the heaviest planes at MTOW can take off with 0 wind over deck.
The more gradual acceleration and higher total power is supposed to make the EMALS superior in those regards vs the old C11 and C13 steam cat.
ALso the speed for landing is high enough for CDG to work with all its planes, also only 28-ish knots and that is even smaller than the future UK CVF.
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just a follow up question.
All this made me wonder, why doesn't the RN opt for a Nuclear propulsion
for their carriers?
Sure it must be a little more expensive to install (200 million $ per reactor acc. to US NAVY) but so is fuel I would guess, also it would have gotten rid of the exhaust, made for a better smalller island , and limitless 20 year full speed, I would think?
Not that it would need to be a British design, but an American of the shelf reactor like the new A1B on the CVN78 would have done the job , no?
+150000HP is about what you get now with the complex setup of no less than 6 powersources, all of different size and even different fueltypes (GAS and diesel).
https://netfiles.uiuc.edu/mragheb/ww...Propulsion.pdf
Or is this just a dumb question on my behalf ?
All this made me wonder, why doesn't the RN opt for a Nuclear propulsion
for their carriers?
Sure it must be a little more expensive to install (200 million $ per reactor acc. to US NAVY) but so is fuel I would guess, also it would have gotten rid of the exhaust, made for a better smalller island , and limitless 20 year full speed, I would think?
Not that it would need to be a British design, but an American of the shelf reactor like the new A1B on the CVN78 would have done the job , no?
+150000HP is about what you get now with the complex setup of no less than 6 powersources, all of different size and even different fueltypes (GAS and diesel).
https://netfiles.uiuc.edu/mragheb/ww...Propulsion.pdf
Or is this just a dumb question on my behalf ?
It seems to me JSF is flawed by trying to be too many things-
Replacing F-111s for the RAAF at one end of the spectrum to Harriers and A-10s at the other. oh, by the way, can you also make it to be the second best fighter around (after F-22) for the next 30 years. I'm half surprised it was not pencilled in for tac airlift too.
It seems to me the B model should have been a seperate machine - a Harrier 3? Perhaps then we would have two winning machines on the verge of entering service.
Can anyone enlighten me what plans were afoot for a next generation Harrier before it got swallowed up into JSF?
I would also be interested to know - was differential vectoring of thrust ever tested on a Harrier? By that I mean keeping the aft exhausts pointing backwards and rotating the front ones down (slightly). I always thought it would give a massive boost to turning performance - although at the cost of another button to switch between 2 and 4 nozzle vectoring.
Replacing F-111s for the RAAF at one end of the spectrum to Harriers and A-10s at the other. oh, by the way, can you also make it to be the second best fighter around (after F-22) for the next 30 years. I'm half surprised it was not pencilled in for tac airlift too.
It seems to me the B model should have been a seperate machine - a Harrier 3? Perhaps then we would have two winning machines on the verge of entering service.
Can anyone enlighten me what plans were afoot for a next generation Harrier before it got swallowed up into JSF?
I would also be interested to know - was differential vectoring of thrust ever tested on a Harrier? By that I mean keeping the aft exhausts pointing backwards and rotating the front ones down (slightly). I always thought it would give a massive boost to turning performance - although at the cost of another button to switch between 2 and 4 nozzle vectoring.
The carrier speed doesn't affect EMALS which is indeed a zero wod system. Nor does it prevent recovery. Low speed just adds a level of operational embuggerance in certain scenarios , that's all.
As for a kettle powered ship, you have to realise that the decision was taken in the mid-90s, when all of a sudden the decommissioning costs of nuclear ships began to look scary (see the sixteen or so old subs we still have floating in Rosyth & Devonport). The lack of somewhere to store the waste at end of life and the high costs basically killed it without much in way of detailed study.
Given the current debate about PWR3 and UK reactor design capability, a few years later might have brought a different conclusion. Difficult to say really.
As for a kettle powered ship, you have to realise that the decision was taken in the mid-90s, when all of a sudden the decommissioning costs of nuclear ships began to look scary (see the sixteen or so old subs we still have floating in Rosyth & Devonport). The lack of somewhere to store the waste at end of life and the high costs basically killed it without much in way of detailed study.
Given the current debate about PWR3 and UK reactor design capability, a few years later might have brought a different conclusion. Difficult to say really.
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Lockheed Martin started it by calling the F35 'Lightning'.
What of it, if you don't mind me asking?
What of it, if you don't mind me asking?
At appx £200m an aircraft ,with Spitfires /Seafires on the market at £2m each,I think it would be much better if this F-35 was ditched and we bought some quality aircraft instead....Much better for the anoraks,sound better,look better,quantity over perhaps quality;;; As the USAF blame the pilot for the loss of an F-22,because of a design failure,what will happen when someone ditches one of these `wonderful`5th generation warbirds..... What a `waste of space`; who are we presumed to be going up against anyway..? China..? NKorea..? bunch of Somali pirates ?
Fascinating thread-thanks all.
Now that does beg the question, did anyone presume in say, 1980 that a war with Argentina would be on the cards within a couple of years?
What a `waste of space`; who are we presumed to be going up against anyway..? China..? NKorea..? bunch of Somali pirates ?
Now that does beg the question, did anyone presume in say, 1980 that a war with Argentina would be on the cards within a couple of years?
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With regards to the nuclear propulsion; the only conclusion that I can come to, is that non-nuclear propulsion looked good for short term finances for both its construction years and the years following the end of its service life...the labour government was all about making the numbers look good, even if the underlying truth wasn't good!
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Windspeed, a question.
The F35C doens't need any windspeed to get launched at MTOW with the new EMALS, that much seems to be clear now.
What about the F35B, could that lift off with a skijump at MTOW but without
windspeed over deck ?
The F35C doens't need any windspeed to get launched at MTOW with the new EMALS, that much seems to be clear now.
What about the F35B, could that lift off with a skijump at MTOW but without
windspeed over deck ?
The non-nuclear decision predated the election of the Smiling Menace and his mate the Financial Genius, believe it or not, when the ship was called CV(R). Yes, the gestation has been that long!
As for whether the B will do MTOW with zero WoD/ski-jump, I don't know. ISTR the requirement may have been for that, but don't know whether that stuck. Engines will probably know, but not sure whether it's releasable or not.
As for whether the B will do MTOW with zero WoD/ski-jump, I don't know. ISTR the requirement may have been for that, but don't know whether that stuck. Engines will probably know, but not sure whether it's releasable or not.
Do a Hover - it avoids G
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kbrockman
Windspeed over deck is a landing problem for a trap. Too little and you have the hook out or break the wires.
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too little wind on landing
That's how I figured it would be, I was specifically talking about the
take-off fase.
However, your remark got me thinking, would the 25 knot speed of the new CVF's be to little, to slow ?
As far as I know, the French carrier sails at max 27 knts and it seems to do ok, also with E2 , C2 and the heavy superhornets, no?
Also don't the Naval aviators usually also practise landing on a simulated
portion of dedicated airfields that have a Carrier deck layout incl complete Arrestor wire systems ?
They don't move forward and therefor don't have an extra windcomponent, granted the planes are probably at or close to minimum weight when landing meaning lower app speed and lower stress on the frame , but still ?
Somewhere in Russia;
take-off fase.
However, your remark got me thinking, would the 25 knot speed of the new CVF's be to little, to slow ?
As far as I know, the French carrier sails at max 27 knts and it seems to do ok, also with E2 , C2 and the heavy superhornets, no?
Also don't the Naval aviators usually also practise landing on a simulated
portion of dedicated airfields that have a Carrier deck layout incl complete Arrestor wire systems ?
They don't move forward and therefor don't have an extra windcomponent, granted the planes are probably at or close to minimum weight when landing meaning lower app speed and lower stress on the frame , but still ?
Somewhere in Russia;
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It's the NITKA facility in the Ukraine actually, and they are rumoured to be about to rent it out to the Chinese and/or the Indians in the near future as well as the Russians!
As to the CVF speed, officially 25+ knots. The 'plus' bit is telling to me. The RN has a track record of understating the top speed of it's warships, for years the Invincibles were quoted as being capable of 28 knots, but in the last decade the figure seems to have been revised to 30 knots... I iwould personally be surprised if the CVFs could only do 25 nots in service, but it should also be remembered that Wind-Over-Deck is normally composed of ship speed and local wind, hence the order to 'turn the ship into the wind' before flying operations commence. Nil wind conditions certainly are a factor, but by no means the norm for carrier ops.
As to the CVF speed, officially 25+ knots. The 'plus' bit is telling to me. The RN has a track record of understating the top speed of it's warships, for years the Invincibles were quoted as being capable of 28 knots, but in the last decade the figure seems to have been revised to 30 knots... I iwould personally be surprised if the CVFs could only do 25 nots in service, but it should also be remembered that Wind-Over-Deck is normally composed of ship speed and local wind, hence the order to 'turn the ship into the wind' before flying operations commence. Nil wind conditions certainly are a factor, but by no means the norm for carrier ops.