No cats and flaps ...... back to F35B?
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Thats not true
Theres no reason why you can't investigate technology independently of actual production. Used to happen in the past: the P.1127 is a good example, the Fairy Delta another. or more recently, the work on the rewinged FBW "unstable" Jaguar (sorry, I can't remember the acronym for it)
Those sort of aircraft all provided technical information as to what was possible - and could be used in a new model
Even the Spitfire was only possible because of the work on the Schneider Trophy aircraft - which were basically pure experiments
Theres no reason why you can't investigate technology independently of actual production. Used to happen in the past: the P.1127 is a good example, the Fairy Delta another. or more recently, the work on the rewinged FBW "unstable" Jaguar (sorry, I can't remember the acronym for it)
Those sort of aircraft all provided technical information as to what was possible - and could be used in a new model
Even the Spitfire was only possible because of the work on the Schneider Trophy aircraft - which were basically pure experiments
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Milo Minderbinder,
I totally agree that in a perfect world that lots of different technologies would be developed and tested. Unfortunately companies need to make a profit to keep shareholders happy and to not go bankrupt, so development when their are no sales won't be perceived as being acceptable. The governments of today can't afford to fund such projects either. A slight generalisation there as it does happen, but on a small scale. We also rarely see the type of persons who are generous enough to aid such developments through magnanimity these days.
The Jaguar FBW aircraft was called Active Control Technology (ACT). Registration was XX765.
I totally agree that in a perfect world that lots of different technologies would be developed and tested. Unfortunately companies need to make a profit to keep shareholders happy and to not go bankrupt, so development when their are no sales won't be perceived as being acceptable. The governments of today can't afford to fund such projects either. A slight generalisation there as it does happen, but on a small scale. We also rarely see the type of persons who are generous enough to aid such developments through magnanimity these days.
The Jaguar FBW aircraft was called Active Control Technology (ACT). Registration was XX765.
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>>>The F-35 series of fighters are highly complex systems that will work, sometime.
I doubt it.
The F35b carries a large lift-fan, when there is no need for one whatsoever. It has trouble transitioning to the hover, because of fan door and airflow issues. It cannot go supersonic without returning to base after five minutes. It cannot vector in flight. The 'c' version cannot catch a cable, without a hook so long you could see it on your weather radar. And now to increase performance, it has external stores - "hey, Bud, why can every radar in Eyerakk see me?" Duhhhhh...
So in the end, after all this computer designed cutting edge technology, we will not get anything better than the 1970s Harrier. Happy days.
I doubt it.
The F35b carries a large lift-fan, when there is no need for one whatsoever. It has trouble transitioning to the hover, because of fan door and airflow issues. It cannot go supersonic without returning to base after five minutes. It cannot vector in flight. The 'c' version cannot catch a cable, without a hook so long you could see it on your weather radar. And now to increase performance, it has external stores - "hey, Bud, why can every radar in Eyerakk see me?" Duhhhhh...
So in the end, after all this computer designed cutting edge technology, we will not get anything better than the 1970s Harrier. Happy days.
The theory for bigger carriers was sound.
No it wasn't. A nation has to live according to its budget. To have had four smaller carriers would have been much more flexible and probably cheaper (economies of scale) than two large ones. It was the most stupid idea ever, and who knows why the Admiralty fell for it.
Utter hoop I'm afraid. Every single study by any nation on taking aircraft to sea since the 1970s has conclusively demonstrated that both in terms of UPC and also operating costs, economy of scale favours larger ships. Or do you really think duplicating the required facilities and personnel for ops across more ships can somehow work out cheaper?
The external stores issue is to allow for flexibility in a situation where additional weapons / fuel might be more useful for that particular situation than an LO configuration.
As for the debate on aarse about survivability, that too is being conducted from a level of misconception as to STOVL ops. The nub of the argument appears to be that "a bomb crater" in the flightdeck will preclude cat n'trap operations. This conveniently misses the point that there will be two cats in different locations and also that without access to a ski-ramp and it's runway, which is a larger target than a cat and might therefore be statistically more likely to suffer damage, STO becomes VTO which is just about enough to get you off the deck to circle the ship and then land again. There are some detailed differences in survivability between the two modes, but the actual delta is literally in single figures of percent.
These things have been done to death years ago if you know where to look.
No it wasn't. A nation has to live according to its budget. To have had four smaller carriers would have been much more flexible and probably cheaper (economies of scale) than two large ones. It was the most stupid idea ever, and who knows why the Admiralty fell for it.
Utter hoop I'm afraid. Every single study by any nation on taking aircraft to sea since the 1970s has conclusively demonstrated that both in terms of UPC and also operating costs, economy of scale favours larger ships. Or do you really think duplicating the required facilities and personnel for ops across more ships can somehow work out cheaper?
The external stores issue is to allow for flexibility in a situation where additional weapons / fuel might be more useful for that particular situation than an LO configuration.
As for the debate on aarse about survivability, that too is being conducted from a level of misconception as to STOVL ops. The nub of the argument appears to be that "a bomb crater" in the flightdeck will preclude cat n'trap operations. This conveniently misses the point that there will be two cats in different locations and also that without access to a ski-ramp and it's runway, which is a larger target than a cat and might therefore be statistically more likely to suffer damage, STO becomes VTO which is just about enough to get you off the deck to circle the ship and then land again. There are some detailed differences in survivability between the two modes, but the actual delta is literally in single figures of percent.
These things have been done to death years ago if you know where to look.
Whatever they order is going to get cancelled anyway, so the whole argument is pointless
However, they will order the - B. and then cancel it. Why? Because as its the more expensive aircraft, they will be able to announce bigger savings when its chopped.
Of course they'll be able to offer an earlier saving by not buying the catapults.
So ....first they announce the most expensive carrier option - and then pull back, so saving a fortune that they were never going to spend anyway, and then they save an even bigger fortune by not buying the aircraft they were never going to buy
However, they will order the - B. and then cancel it. Why? Because as its the more expensive aircraft, they will be able to announce bigger savings when its chopped.
Of course they'll be able to offer an earlier saving by not buying the catapults.
So ....first they announce the most expensive carrier option - and then pull back, so saving a fortune that they were never going to spend anyway, and then they save an even bigger fortune by not buying the aircraft they were never going to buy
And IMHO, the most likely scenario that will occur.
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Silverstrata,
The Harrier had its' own complexities and design limitations. Perhaps the additional lift fan is an attempt to get around these limitations. All aircraft development programmes suffer problems. These are resolved.
I don't see a design fault with the fan door as being a major problem. Most aircraft undergo inlet design changes. As for being unable to catch a cable, that is a current problem that will be resolved also.
Having written the above, I have never been a supporter of over complex kit. Adding things just means there is something else to go wrong. Complex things go wrong more often.
Personally I can't see why they didn't take the basic Harrier principle further by producing a supersonic airframe. Wouldn't look the same but there is an awful lot of technology in the Harrier to provide a base line to start from.
The Harrier had its' own complexities and design limitations. Perhaps the additional lift fan is an attempt to get around these limitations. All aircraft development programmes suffer problems. These are resolved.
I don't see a design fault with the fan door as being a major problem. Most aircraft undergo inlet design changes. As for being unable to catch a cable, that is a current problem that will be resolved also.
Having written the above, I have never been a supporter of over complex kit. Adding things just means there is something else to go wrong. Complex things go wrong more often.
Personally I can't see why they didn't take the basic Harrier principle further by producing a supersonic airframe. Wouldn't look the same but there is an awful lot of technology in the Harrier to provide a base line to start from.
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Not_a_boffin,
You are correct in what you write. I would write though that redundancy is provided by having four smaller ships. I would also like to add that there is no point starting to build ships when one is going to be sold (probably) leaving us with one ship. From my experience you really need to have three/ four ships to provide full time use. You normally have two in various stages of refit and upgrades, one sailing back to port and one sailing out from port.
The fact that we can't afford any ships is irrelevant. Think of all those wasted billions that could have been used to purchase further Astute class submarines or Type 45 Destroyers.
You are correct in what you write. I would write though that redundancy is provided by having four smaller ships. I would also like to add that there is no point starting to build ships when one is going to be sold (probably) leaving us with one ship. From my experience you really need to have three/ four ships to provide full time use. You normally have two in various stages of refit and upgrades, one sailing back to port and one sailing out from port.
The fact that we can't afford any ships is irrelevant. Think of all those wasted billions that could have been used to purchase further Astute class submarines or Type 45 Destroyers.
Last edited by hval; 20th Mar 2012 at 22:01. Reason: Added additional sentence
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Guys,
Just a little proportion here.
Yes, the UK is broke and any defence spending is going to strain the budgets, which are broken anyway, but...
The carriers are not going to 'cripple the Defence budget for years'.Let's look at some NAO figures. Last cost to completion for QE2 class carriers was £5.1bn. Let's look at some other programmes. How about Typhoon, which the NAO reports will cost £20.2bn for 160 aircraft, with total cost of £37bn. How about FSTA at £12bn, or perhaps Meteor at £1.15bn?
Yes, choices have to be made. I'm damn glad I don't have to make them. But the carriers are one part of a broken budget. Personally, I'm not convinced that spending £37bn on an AD aircraft with a very secondary AG capability represents best value for money right now, but I'm not the guy making the calls.
Just a response to silverstrata -
1. The F-35B does not have 'trouble' doing a transition to the hover. It did, that's why the lift fan door was redesigned after the X-35 programme. Now it doesn't. Oh, and a Brit led the redesign.
2. The B needs a lift fan because it is required to land vertically. It's a STOVL aircraft. Sorry if this sounds obvious - but it is.
3. The B can't vector in flight because there was no requirement for it to do so. Harrier doesn't use VIFF operationally.
4. The B (and A and C) has issues right now with supersonic flight due to heat effects on the aft fuselage. This will be fixed.
5. The C has experienced problems with arresting gear tests. A longer hook probably wouldn't be the fix they will choose - they're looking at hook tip and damper rates. If these don't work, they are in real trouble - but they're not, not yet.
6. Like every variant of the F-35, the C is designed to carry external stores as an option when really 'low' LO isn't required. It's a requirement to give flexibility to the system, unlike the F-117, B-2 and other legacy stealth aircraft.
HVAL - sadly, all the studies carried out for around 15 years by the UK and the US showed that the Harrier layout would just not go supersonic in any meaningful way, and carry the avionics and internal stores required. LM were right to go for a concept that split the lift fan and thrust engine and put the thrust engine at the back of the aircraft.
Have a pop at the aircraft by all means - it's a free forum. But look at the facts, then make up your mind. And make any judgement you like - free country.
Very Best Regards
Engines
Just a little proportion here.
Yes, the UK is broke and any defence spending is going to strain the budgets, which are broken anyway, but...
The carriers are not going to 'cripple the Defence budget for years'.Let's look at some NAO figures. Last cost to completion for QE2 class carriers was £5.1bn. Let's look at some other programmes. How about Typhoon, which the NAO reports will cost £20.2bn for 160 aircraft, with total cost of £37bn. How about FSTA at £12bn, or perhaps Meteor at £1.15bn?
Yes, choices have to be made. I'm damn glad I don't have to make them. But the carriers are one part of a broken budget. Personally, I'm not convinced that spending £37bn on an AD aircraft with a very secondary AG capability represents best value for money right now, but I'm not the guy making the calls.
Just a response to silverstrata -
1. The F-35B does not have 'trouble' doing a transition to the hover. It did, that's why the lift fan door was redesigned after the X-35 programme. Now it doesn't. Oh, and a Brit led the redesign.
2. The B needs a lift fan because it is required to land vertically. It's a STOVL aircraft. Sorry if this sounds obvious - but it is.
3. The B can't vector in flight because there was no requirement for it to do so. Harrier doesn't use VIFF operationally.
4. The B (and A and C) has issues right now with supersonic flight due to heat effects on the aft fuselage. This will be fixed.
5. The C has experienced problems with arresting gear tests. A longer hook probably wouldn't be the fix they will choose - they're looking at hook tip and damper rates. If these don't work, they are in real trouble - but they're not, not yet.
6. Like every variant of the F-35, the C is designed to carry external stores as an option when really 'low' LO isn't required. It's a requirement to give flexibility to the system, unlike the F-117, B-2 and other legacy stealth aircraft.
HVAL - sadly, all the studies carried out for around 15 years by the UK and the US showed that the Harrier layout would just not go supersonic in any meaningful way, and carry the avionics and internal stores required. LM were right to go for a concept that split the lift fan and thrust engine and put the thrust engine at the back of the aircraft.
Have a pop at the aircraft by all means - it's a free forum. But look at the facts, then make up your mind. And make any judgement you like - free country.
Very Best Regards
Engines
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Engines,
Apologies, I obviously wasn't clear in what I wrote (making pesto and typing at the same time is not a good idea). I agree the current Harrier airframe can not be made to go supersonic. I was talking about a new airframe with some of the Harrier ideas used.
Personally I don't like the F-35 aircraft, but then I was not fond of the Tornado. That eventually became a good aircraft. I do believe that the F-35 will work.
Apologies, I obviously wasn't clear in what I wrote (making pesto and typing at the same time is not a good idea). I agree the current Harrier airframe can not be made to go supersonic. I was talking about a new airframe with some of the Harrier ideas used.
Personally I don't like the F-35 aircraft, but then I was not fond of the Tornado. That eventually became a good aircraft. I do believe that the F-35 will work.
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HVAL,
Thanks for coming back - hope the pesto turned out right!
The basic problem with the Harrier concept (one engine providing both lift and thrust) was that to get the thrust required to allow a sensibly capable combat aircraft (around 35 to 40 thousand pounds) to hover required an engine just too big for sustained supersonic flight. Cross section got too big, and using hot gas to provide the main lift effort just didn't work.
The other problem with a big engine in the middle of the aircraft, driven by CG, is that it displaces lots of other stuff you want to put there. One of the major issues with the F-35 weight saving effort was to redesign the aircraft to put lots of bits and pieces back in their proper places. Having a dirty great engine in the middle makes that even harder.
Oner good thing to take away from this thread - STOVL is insanely hard. Supersonic, stealthy STOVL is even harder. Getting the F-35B to where it is, and making it part of a whole family of combat aircraft, is even harder than that. And here's the thing - this achievement (and it is a massive achievement) has included many extremely talented Brits doing things that our American friends could not do. Once in a while, it would be nice to celebrate that.
Hope this helps,
Best Regards
Engines
Thanks for coming back - hope the pesto turned out right!
The basic problem with the Harrier concept (one engine providing both lift and thrust) was that to get the thrust required to allow a sensibly capable combat aircraft (around 35 to 40 thousand pounds) to hover required an engine just too big for sustained supersonic flight. Cross section got too big, and using hot gas to provide the main lift effort just didn't work.
The other problem with a big engine in the middle of the aircraft, driven by CG, is that it displaces lots of other stuff you want to put there. One of the major issues with the F-35 weight saving effort was to redesign the aircraft to put lots of bits and pieces back in their proper places. Having a dirty great engine in the middle makes that even harder.
Oner good thing to take away from this thread - STOVL is insanely hard. Supersonic, stealthy STOVL is even harder. Getting the F-35B to where it is, and making it part of a whole family of combat aircraft, is even harder than that. And here's the thing - this achievement (and it is a massive achievement) has included many extremely talented Brits doing things that our American friends could not do. Once in a while, it would be nice to celebrate that.
Hope this helps,
Best Regards
Engines
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Engines,
Thanks for your response, much appreciated. Your explanation is clear and simple to understand.
I totally agree with your last paragraph.
Pesto did turn out alright; eventually. As I was making it I knew I had left something out but couldn't think what. It was the parmesan. It was only when I was making the pasta that I remembered what I had left out. I hurriedly effected modification.
Thanks for your response, much appreciated. Your explanation is clear and simple to understand.
I totally agree with your last paragraph.
Pesto did turn out alright; eventually. As I was making it I knew I had left something out but couldn't think what. It was the parmesan. It was only when I was making the pasta that I remembered what I had left out. I hurriedly effected modification.
A voyage to the bottom of the Internet yielded an actual link to the story Orac cited above:
Gulf Times ? Qatar?s top-selling English daily newspaper - Britain/Ireland
Cameron had been asked by his defence department, and the Navy in particular, to say that Britain would like to buy the limited Short Take Off Vertical Landing version of the new F-35 Joint Strike Fighter for its two new aircraft carriers...
With the spiralling cost of the catapult apparatus, the Navy switched back to the Stovl or “jump jet version” — grandson of the Harrier — for the new plane. Although the plane is very limited in range and payload, it might enable the Navy to afford both carriers to be fully equipped.
This was to be explained to President Obama. However, voices from Washington suggest that the president said this was no option at all...
It is being circulated that the US is now likely to order only four squadrons of the jump-jet “B” version for the US Marine Corps. Since this would be a maximum of about 65 planes, it is now thought in Washington that this is all a preliminary to cancelling the “B” version altogether.
Defence Secretary Philip Hammond appears to have been asked by Cameron “to go through the figures again” with a view to buying the more expensive “B” F-35 and more expensive carrier with “cats and traps” for the aircraft. No announcement is expected before Easter.
OK, this may be full of
. But this is not the work of the guy who covers TOWIE the other four days a week:
Full profile | guardian.co.uk
Curiouser and curiouser.
Gulf Times ? Qatar?s top-selling English daily newspaper - Britain/Ireland
Cameron had been asked by his defence department, and the Navy in particular, to say that Britain would like to buy the limited Short Take Off Vertical Landing version of the new F-35 Joint Strike Fighter for its two new aircraft carriers...
With the spiralling cost of the catapult apparatus, the Navy switched back to the Stovl or “jump jet version” — grandson of the Harrier — for the new plane. Although the plane is very limited in range and payload, it might enable the Navy to afford both carriers to be fully equipped.
This was to be explained to President Obama. However, voices from Washington suggest that the president said this was no option at all...
It is being circulated that the US is now likely to order only four squadrons of the jump-jet “B” version for the US Marine Corps. Since this would be a maximum of about 65 planes, it is now thought in Washington that this is all a preliminary to cancelling the “B” version altogether.
Defence Secretary Philip Hammond appears to have been asked by Cameron “to go through the figures again” with a view to buying the more expensive “B” F-35 and more expensive carrier with “cats and traps” for the aircraft. No announcement is expected before Easter.
OK, this may be full of
. But this is not the work of the guy who covers TOWIE the other four days a week:Full profile | guardian.co.uk
Curiouser and curiouser.
Hval
I understand your point. However, that level of refit/upgrade activity is not typical of what the RN has generally managed over the last 15 years of operating two CVS and one in reserve. The constraint is always the ships complement and (usually) not buying sufficient aircraft / aircrew to maintain 1CAG per ship.
Personally I'd be surprised if whichever of the two QEC doesn't enter service is actually sold. Partly because there are unlikely to be "acceptable" buyers and partly because if we manage to get both ships in the same configuration, you could run them as we do the LPD.
Additional T45 and Astute are of limited value if you don't have the full-spectrum capability (ie organic air) to do proper Fleet ops. This is the conundrum; either have the balanced fleet with the three core capabilities endorsed by every government over the last thirty years, or; build a small coastal fleet of FAC, OPV and MCMV and stay home. A posture that incidentally has similar implications for the Army & RAF.
I understand your point. However, that level of refit/upgrade activity is not typical of what the RN has generally managed over the last 15 years of operating two CVS and one in reserve. The constraint is always the ships complement and (usually) not buying sufficient aircraft / aircrew to maintain 1CAG per ship.
Personally I'd be surprised if whichever of the two QEC doesn't enter service is actually sold. Partly because there are unlikely to be "acceptable" buyers and partly because if we manage to get both ships in the same configuration, you could run them as we do the LPD.
Additional T45 and Astute are of limited value if you don't have the full-spectrum capability (ie organic air) to do proper Fleet ops. This is the conundrum; either have the balanced fleet with the three core capabilities endorsed by every government over the last thirty years, or; build a small coastal fleet of FAC, OPV and MCMV and stay home. A posture that incidentally has similar implications for the Army & RAF.
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Not_a_boffin,
I agree that we need a complete range of systems to provide adequate defence, whether this be Navy, Army or Royal Air Force. This need includes aircraft carriers (with aircraft).
Unfortunately there are many items missing, including LRMP, sufficient ASW asets, sufficient air defence assets, sufficient submarines, manpower etc. It therefore comes down to what provides maximum protection for the money available. The system must be robust. I really don't feel that the aircraft carrier are it.
As for a coastal fleet. I do feel that we need to increase the size of this.
It will be interesting to see what does happen with the aircraft carriers and the aircraft that should go with them.
I agree that we need a complete range of systems to provide adequate defence, whether this be Navy, Army or Royal Air Force. This need includes aircraft carriers (with aircraft).
Unfortunately there are many items missing, including LRMP, sufficient ASW asets, sufficient air defence assets, sufficient submarines, manpower etc. It therefore comes down to what provides maximum protection for the money available. The system must be robust. I really don't feel that the aircraft carrier are it.
As for a coastal fleet. I do feel that we need to increase the size of this.
It will be interesting to see what does happen with the aircraft carriers and the aircraft that should go with them.
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Read it and weep.
The good news keeps on coming
http://www.dodbuzz.com/2012/03/20/mo...inty-for-f-35/
F35B probation lift "meaningless"
Software, software, software
Helmet problems that just wont go away
Price inflation for the umptiest time
overall cost now close to 400billion (up from 382)
still design changes expected
testing still at a very low (but steady) pace
rework finished frames 372 million$ on already produced frames payed by government, total = 1 billion$
More specifically on the 'B'
but most remarkable
The good news keeps on coming
http://www.dodbuzz.com/2012/03/20/mo...inty-for-f-35/
F35B probation lift "meaningless"
Software, software, software
Helmet problems that just wont go away
Price inflation for the umptiest time
overall cost now close to 400billion (up from 382)
still design changes expected
testing still at a very low (but steady) pace
rework finished frames 372 million$ on already produced frames payed by government, total = 1 billion$
program now estimates that the number of changes will persist at elevated levels through 2019. Even with the substantial reductions in near-term procurement quantities, DOD is still investing billions of dollars on hundreds of aircraft while flight testing has years to go.
While several technical issues have been addressed and some potential solutions engineered, assessing whether the deficiencies are resolved is ongoing and, in some cases, will not be known for years. According to the program office, two of the five specific problems cited are considered to be fixed while the other three have temporary fixes in place. The Director, Operational Test and Evaluation reported that significant work remains to verify and incorporate modifications to correct known STOVL deficiencies and prepare the system for operational use. Until the proposed technical solutions have been fully tested and demonstrated, it cannot be determined if the technical problems have been resolved.
So it’s another barrage of bad news for the Joint Strike Fighter, although the few House lawmakers who showed up for Tuesday’s brief hearing appeared mostly bored about it. Of the little discussion there was, no one broached cancellation. In fact, their outward lack of interest in the F-35 could be a sign of resignation — an ultimate acceptance that a program this big, this important, can endure almost anything.
Gentleman Aviator
Personally I can't see why they didn't take the basic Harrier principle further by producing a supersonic airframe.
P1154...cancelled in 1965
Cool what-if art... Sadly, though, the PCB (front nozzle reheat) on landing would have been a bit of a sodder in terms of ground environment. Even worse than the Bs back end!
Gentleman Aviator
True LowObs, but they'd have had 47 years to sort it out .......
And IIRC was to have been a single-seater for the crabs, and a tandem for the WAFUs.
And IIRC was to have been a single-seater for the crabs, and a tandem for the WAFUs.
Do a Hover - it avoids G
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Supersonic vertical lander.
Many people have asked me why we never did a supersonic Harrier. My answer to them all was that the Harrier layout did not allow it. To fly supersonically requires an engine specifically designed to produce a very high speed exhaust. In other words the nature of the thrust is important, not just the amount of it.
The physics behind this are remarkably simple. The thrust of a jet engine is calculated by multiplying together just two numbers M and V. M is the mass or amount of air passing through the engine in a given time (pounds per second using the units I was taught at school) while V is the speed increase that the engine imparts to the air as it passes through the engine (feet per second in my day).
With both the Harrier (a typical subsonic fighter) and the F-16 (a typical supersonic fighter) the product of M x V is about 20,000. However the difference between the two aircraft is that the Harrier engine gets its 20,000 by using a big value of M and a modest value of V while the F-16 engine uses a modest value of M but gives it a bigger V.
While 20,000 lb of thrust is plenty to get a small fighter supersonic, it will only do so if the V component of that 20,000 is big enough.
The Harrier engine deliberately uses a small V because a big V would have the ability to damage the surface below it during a VTO and, if not the surface then the under-surfaces of the aircraft itself. Additionally and very importantly, an engine that produces a big V can only do this by making the exhaust very hot. Immersing the bottom of a Harrier and its rubber tyres in such a hot environment would clearly not work.
Helicopters are subject to the same physics regarding thrust so, in the case of a large 20,000 lb helicopter, it uses a huge M (captured by the rotor) and gives it a very small V (the downwash we can feel or see blowing stuff about under a helicopter) but the product is still 20,000.
All this means that you need a different configuration of aircraft from that of the Harrier if you want to produce a practical supersonic vertical landing aircraft.
Finally, any succesful jet lift vertical landing design MUST as in ABSOLUTELY MUST keep efflux that has had fuel burned in it out of the intake during VTO or VL. The Harrier does this by having a front nozzle efflux that splashes reawards and stops the hot air coming forwards. The B does the same thing using the fan efflux.
The physics behind this are remarkably simple. The thrust of a jet engine is calculated by multiplying together just two numbers M and V. M is the mass or amount of air passing through the engine in a given time (pounds per second using the units I was taught at school) while V is the speed increase that the engine imparts to the air as it passes through the engine (feet per second in my day).
With both the Harrier (a typical subsonic fighter) and the F-16 (a typical supersonic fighter) the product of M x V is about 20,000. However the difference between the two aircraft is that the Harrier engine gets its 20,000 by using a big value of M and a modest value of V while the F-16 engine uses a modest value of M but gives it a bigger V.
While 20,000 lb of thrust is plenty to get a small fighter supersonic, it will only do so if the V component of that 20,000 is big enough.
The Harrier engine deliberately uses a small V because a big V would have the ability to damage the surface below it during a VTO and, if not the surface then the under-surfaces of the aircraft itself. Additionally and very importantly, an engine that produces a big V can only do this by making the exhaust very hot. Immersing the bottom of a Harrier and its rubber tyres in such a hot environment would clearly not work.
Helicopters are subject to the same physics regarding thrust so, in the case of a large 20,000 lb helicopter, it uses a huge M (captured by the rotor) and gives it a very small V (the downwash we can feel or see blowing stuff about under a helicopter) but the product is still 20,000.
All this means that you need a different configuration of aircraft from that of the Harrier if you want to produce a practical supersonic vertical landing aircraft.
Finally, any succesful jet lift vertical landing design MUST as in ABSOLUTELY MUST keep efflux that has had fuel burned in it out of the intake during VTO or VL. The Harrier does this by having a front nozzle efflux that splashes reawards and stops the hot air coming forwards. The B does the same thing using the fan efflux.