avatar_Thorvic

F-35B may well become a What-if program !

Started by Thorvic, January 06, 2011, 04:07:54 PM

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Thorvic

Well it looks like the F-35B as an operational aircraft may well end up a What-if, Gates has put it on 2 yrs probation to fix its problems or it it gets cancelled !!

http://www.flightglobal.com/articles/2011/01/06/351600/us-military-unveils-possible-f-35b-redesign-in-sweeping-budget.html

http://www.aviationweek.com/aw/blogs/defense/index.jsp?plckController=Blog&plckBlogPage=BlogViewPost&newspaperUserId=27ec4a53-dcc8-42d0-bd3a-01329aef79a7&plckPostId=Blog%3a27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post%3ab8a1e69a-f078-4436-bd44-51b1167f9db4&plckScript=blogScript&plckElementId=blogDest

Now we know why the UK jumped ship to the CATOBAR CVF & F-35C, as there is no way they cold base their future Carrier Strike policy on a system that is in serious danger of being cancelled !!!.
Project Cancelled SIG Secretary, specialising in post war British RN warships, RN and RAF aircraft projects. Also USN and Russian warships

chrisonord

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If you cant eat it hump it or fight it,
Pee on it and walk away!!

Maverick

One wonders if the idea of a separate lift motor is that clever.  At the end of the day, it's just extra weight the thing is hauling when not VTOLing.  I was astonished when I found out that was the case back in the day for the F-35B.  Whilst not as fancy, one would think that the Pegasus concept is much more doable.

Regards,

Mav

PR19_Kit

#3
Quote from: Maverick on January 06, 2011, 04:30:58 PM
One wonders if the idea of a separate lift motor is that clever.  At the end of the day, it's just extra weight the thing is hauling when not VTOLing.  I was astonished when I found out that was the case back in the day for the F-35B.  Whilst not as fancy, one would think that the Pegasus concept is much more doable.

AFAIK the F-35B doesn't have a separate lift engine as such. The main engine has the world's biggest clutch at the front end which connects to a lift fan that's just behind the cockpit. In VTOL mode the fan is clutched in and the exhaust pipe translates through 90 deg to produce the vertical thrust.

I doubt you'd get much arguement from Rolls-Royce or BAe over the Pegasus concept versus the F135 all the same, the lift fan and clutch have nothing to do in conventional flight.

Way back in 1965 the Bristol BS100 engine was already producing 84% of the thrust of the F135, and that didn't need clutches or fans either.............  :-\

Kit's Rule 1 ) Any aircraft can be improved by fitting longer wings, and/or a longer fuselage
Kit's Rule 2) The backstory can always be changed to suit the model

...and I'm not a closeted 'Take That' fan, I'm a REAL fan! :)

Regards
Kit

Taiidantomcat

Quote from: Thorvic on January 06, 2011, 04:07:54 PM

Now we know why the UK jumped ship to the CATOBAR CVF & F-35C, as there is no way they cold base their future Carrier Strike policy on a system that is in serious danger of being cancelled !!!.

No, the UK just has no money  ;D Also the F-35C is not exactly proceeding perfectly itself.  There are structural concerns, landing gear issues, and a few other problems, so it wasn't to dodge some technical bullet. They have pushed the whole F-35 schedule up, since they canceled the F-22-- so yeah there will be problems. Also the F-35Bs main problems are things like doors not opening and some structural cracks, things that are solvable given a bit more time, and not uncommon with new aircraft.

If the USMC wants it, they will get it. The Osprey is a case in point. The USMC has based it's entire future on the F-35B... it will happen one way or another even if it exceeds two years. The Osprey got killed and resurrected at least 3 times over its development phase. Moreover, if the F-35B goes belly up the Navy and USAF will push to buy more superbugs, and restart f-22 production.  The only people who are excited about the F-35 is the USMC.
"Imagination is the one weapon in the war against reality." -Jules de Gaultier

"My model is right! It's the real world that's wrong!" -global warming scientist

An armor guy, who builds airplanes almost exclusively, that he converts to space fighters-- all while admiring ship models.

dy031101

It got me wondering...... has there ever been attempt by the USN to absorb the fixed-wing tactical aviation arm of the USMC?
To the individual soldiers, *everything* is a frontal assault!

====================

Current Hobby Priority...... Sigh......

To-do list here

rickshaw

Quote from: PR19_Kit on January 06, 2011, 04:44:18 PM
Quote from: Maverick on January 06, 2011, 04:30:58 PM
One wonders if the idea of a separate lift motor is that clever.  At the end of the day, it's just extra weight the thing is hauling when not VTOLing.  I was astonished when I found out that was the case back in the day for the F-35B.  Whilst not as fancy, one would think that the Pegasus concept is much more doable.

AFAIK the F-35B doesn't have a separate lift engine as such. The main engine has the world's biggest clutch at the front end which connects to a lift fan that's just behind the cockpit. In VTOL mode the fan is clutched in and the exhaust pipe translates through 90 deg to produce the vertical thrust.

I doubt you'd get much arguement from Rolls-Royce or BAe over the Pegasus concept versus the F135 all the same, the lift fan and clutch have nothing to do in conventional flight.

Way back in 1965 the Bristol BS100 engine was already producing 84% of the thrust of the F135, and that didn't need clutches or fans either.............  :-\

That clutching system has some interestingly proposed upgrade possibilities.  One of the future ideas for F-35 development involve placing a whacking great dynamo on the clutch and putting a solid state laser in the area occupied by the lift-fan.  This would have lenses projecting upwards and downwards and be computer controlled, creating a very large laser system in the multi-megawatt range.  Great for zapping planes, missiles, soldiers, etc.

The problem with the Pegasus concept is that it severely limits engine power and therefore aircraft speed.  If you introduce tricks like Plenum Burning to increase both, you pay the penalty in having to have specialised landing/take-off pads otherwise you end up melting runways/decks.  Then there is the problem of the drag that the large intakes require and of course, their effect on the stealthiness of the aircraft.  These are all compromises which need to be understood and addressed if considering the use of a "bigger, better" Pegasus style V/STOL aircraft.  Which is course why we've never seen one.
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

dy031101

Quote from: rickshaw on January 06, 2011, 06:05:55 PM
Quote from: PR19_Kit on January 06, 2011, 04:44:18 PM
Quote from: Maverick on January 06, 2011, 04:30:58 PM
One wonders if the idea of a separate lift motor is that clever.  At the end of the day, it's just extra weight the thing is hauling when not VTOLing.  I was astonished when I found out that was the case back in the day for the F-35B.  Whilst not as fancy, one would think that the Pegasus concept is much more doable.

AFAIK the F-35B doesn't have a separate lift engine as such. The main engine has the world's biggest clutch at the front end which connects to a lift fan that's just behind the cockpit. In VTOL mode the fan is clutched in and the exhaust pipe translates through 90 deg to produce the vertical thrust.

I doubt you'd get much arguement from Rolls-Royce or BAe over the Pegasus concept versus the F135 all the same, the lift fan and clutch have nothing to do in conventional flight.

Way back in 1965 the Bristol BS100 engine was already producing 84% of the thrust of the F135, and that didn't need clutches or fans either.............  :-\

That clutching system has some interestingly proposed upgrade possibilities.  One of the future ideas for F-35 development involve placing a whacking great dynamo on the clutch and putting a solid state laser in the area occupied by the lift-fan.  This would have lenses projecting upwards and downwards and be computer controlled, creating a very large laser system in the multi-megawatt range.  Great for zapping planes, missiles, soldiers, etc.

The problem with the Pegasus concept is that it severely limits engine power and therefore aircraft speed.  If you introduce tricks like Plenum Burning to increase both, you pay the penalty in having to have specialised landing/take-off pads otherwise you end up melting runways/decks.  Then there is the problem of the drag that the large intakes require and of course, their effect on the stealthiness of the aircraft.  These are all compromises which need to be understood and addressed if considering the use of a "bigger, better" Pegasus style V/STOL aircraft.  Which is course why we've never seen one.

I thought people here are kinda re-visiting the system used by the X-32.

Although I'm under the impression that the vectoring-nozzles-only system produced an engine that runs the entire mid and aft fuselage...... was there any usable space between the liftfan and the main engine on the F-35?
To the individual soldiers, *everything* is a frontal assault!

====================

Current Hobby Priority...... Sigh......

To-do list here

JoeP

Quote from: dy031101 on January 06, 2011, 06:05:15 PM
It got me wondering...... has there ever been attempt by the USN to absorb the fixed-wing tactical aviation arm of the USMC?

While some might have proposed it, the USN and USMC usually are wise enough to keep their missions separate yet co-operating. Marines pound the ground, and the USN provide air cover, higher-level bombing, and ASW and ASuW. Different aircraft for different missions, and no dilution of training trying to teach a Marine to dogfight or an ASW pilot to strafe.
In want of hobby space!  The kitchen table is never stable.  Still managing to get some building done.

rickshaw

Quote from: dy031101 on January 06, 2011, 06:14:09 PM
Quote from: rickshaw on January 06, 2011, 06:05:55 PM
Quote from: PR19_Kit on January 06, 2011, 04:44:18 PM
Quote from: Maverick on January 06, 2011, 04:30:58 PM
One wonders if the idea of a separate lift motor is that clever.  At the end of the day, it's just extra weight the thing is hauling when not VTOLing.  I was astonished when I found out that was the case back in the day for the F-35B.  Whilst not as fancy, one would think that the Pegasus concept is much more doable.

AFAIK the F-35B doesn't have a separate lift engine as such. The main engine has the world's biggest clutch at the front end which connects to a lift fan that's just behind the cockpit. In VTOL mode the fan is clutched in and the exhaust pipe translates through 90 deg to produce the vertical thrust.

I doubt you'd get much arguement from Rolls-Royce or BAe over the Pegasus concept versus the F135 all the same, the lift fan and clutch have nothing to do in conventional flight.

Way back in 1965 the Bristol BS100 engine was already producing 84% of the thrust of the F135, and that didn't need clutches or fans either.............  :-\

That clutching system has some interestingly proposed upgrade possibilities.  One of the future ideas for F-35 development involve placing a whacking great dynamo on the clutch and putting a solid state laser in the area occupied by the lift-fan.  This would have lenses projecting upwards and downwards and be computer controlled, creating a very large laser system in the multi-megawatt range.  Great for zapping planes, missiles, soldiers, etc.

The problem with the Pegasus concept is that it severely limits engine power and therefore aircraft speed.  If you introduce tricks like Plenum Burning to increase both, you pay the penalty in having to have specialised landing/take-off pads otherwise you end up melting runways/decks.  Then there is the problem of the drag that the large intakes require and of course, their effect on the stealthiness of the aircraft.  These are all compromises which need to be understood and addressed if considering the use of a "bigger, better" Pegasus style V/STOL aircraft.  Which is course why we've never seen one.

I thought people here are kinda re-visiting the system used by the X-32.

Although I'm under the impression that the vectoring-nozzles-only system produced an engine that runs the entire mid and aft fuselage...... was there any usable space between the liftfan and the main engine on the F-35?

Quite a lot.  Occupied by fuel and avionics IIRC.
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

Thorvic

QuoteQuite a lot.  Occupied by fuel and avionics IIRC.

Yeap and and as they cocked up the specs after they did their crash diet progam said kit is now failing due to tempertaures exceeding expected tolerences
Project Cancelled SIG Secretary, specialising in post war British RN warships, RN and RAF aircraft projects. Also USN and Russian warships

Thorvic

#11
Quote from: Taiidantomcat on January 06, 2011, 05:06:48 PM
Quote from: Thorvic on January 06, 2011, 04:07:54 PM

Now we know why the UK jumped ship to the CATOBAR CVF & F-35C, as there is no way they cold base their future Carrier Strike policy on a system that is in serious danger of being cancelled !!!.

No, the UK just has no money  ;D Also the F-35C is not exactly proceeding perfectly itself.  There are structural concerns, landing gear issues, and a few other problems, so it wasn't to dodge some technical bullet. They have pushed the whole F-35 schedule up, since they canceled the F-22-- so yeah there will be problems. Also the F-35Bs main problems are things like doors not opening and some structural cracks, things that are solvable given a bit more time, and not uncommon with new aircraft.

No we are just wise enough not to put our eggs in one basket and put faith in an aircraft that may yet be cancelled or seriously delayed. Don't forget the UK still makes nearly a third of each F-35 aircraft so we would only cancel if the program is no longer viable.

However by switching formats to CATOBAR, there is still the option of Super Hornet or Rafale as off the shelf alternatives should the F-35C fail or be seriously delayed. With the F-35B there is no plan B option for STOVL leaving the Carriers as just helo platforms.
Project Cancelled SIG Secretary, specialising in post war British RN warships, RN and RAF aircraft projects. Also USN and Russian warships

PR19_Kit

Quote from: Thorvic on January 06, 2011, 10:32:26 PM
No we are just wise enough not to put our eggs in one basket and put faith in an aircraft that may yet be cancelled or seriously delayed.

Especially as it's happened to us before............ Skybolt for one.
Kit's Rule 1 ) Any aircraft can be improved by fitting longer wings, and/or a longer fuselage
Kit's Rule 2) The backstory can always be changed to suit the model

...and I'm not a closeted 'Take That' fan, I'm a REAL fan! :)

Regards
Kit

Taiidantomcat

Quote from: Thorvic on January 06, 2011, 10:32:26 PM
Quote from: Taiidantomcat on January 06, 2011, 05:06:48 PM
Quote from: Thorvic on January 06, 2011, 04:07:54 PM

Now we know why the UK jumped ship to the CATOBAR CVF & F-35C, as there is no way they cold base their future Carrier Strike policy on a system that is in serious danger of being cancelled !!!.

No, the UK just has no money  ;D Also the F-35C is not exactly proceeding perfectly itself.  There are structural concerns, landing gear issues, and a few other problems, so it wasn't to dodge some technical bullet. They have pushed the whole F-35 schedule up, since they canceled the F-22-- so yeah there will be problems. Also the F-35Bs main problems are things like doors not opening and some structural cracks, things that are solvable given a bit more time, and not uncommon with new aircraft.

No we are just wise enough not to put our eggs in one basket and put faith in an aircraft that may yet be cancelled or seriously delayed. Don't forget the UK still makes nearly a third of each F-35 aircraft so we would only cancel if the program is no longer viable.

However by switching formats to CATOBAR, there is still the option of Super Hornet or Rafale as off the shelf alternatives should the F-35C fail or be seriously delayed. With the F-35B there is no plan B option for STOVL leaving the Carriers as just helo platforms.

Thats a great point. :thumbsup: Sure makes me wonder why the UK spent so much money developing the B in the first place. I guess they decided to cut their losses though.
"Imagination is the one weapon in the war against reality." -Jules de Gaultier

"My model is right! It's the real world that's wrong!" -global warming scientist

An armor guy, who builds airplanes almost exclusively, that he converts to space fighters-- all while admiring ship models.

GTX

Folks,

First up, no one really knows what this "probation" means yet.  What Secretary Gates actually said is this (my emphasis added):

QuoteThe Joint Strike Fighter program received special scrutiny given its substantial cost, ongoing development issues, and its central place in the future of U.S. military aviation. In short, two of the JSF variants, the Air Force version and the Navy's carrier based version, are proceeding satisfactorily.

By comparison, the Marine Corps' short take-off and vertical landing variant is experiencing significant testing problems. These issues may lead to a redesign of the aircraft's structure and propulsion - changes that could add yet more weight and more cost to an aircraft that has little capacity to absorb more of either.

As a result, I am placing the STOVL variant on the equivalent of a two-year probation. If we cannot fix this variant during this time frame and get it back on track in terms of performance, cost and schedule, then I believe it should be cancelled. We will also move the development of the Marine variant to the back of the overall JSF production sequence.
Source

I have already been in contact with the JSF Program People and even they are unsure what this supposedly means for the F-35B let alone the entire F-35 program.  Of course that won't stop the doom and gloom merchants or the anti-F-35 crowd from making up all sorts of stories. :angry:

My own assessment is that the F-35B will continue and will eventually enter service, albeit later than originally hoped.  The USMC introduction of the F-35B was always ambitious (they were to be the first in service with the most complex version!),  The next two years will see a major effort to rectify the issues that have brought this delay about both from Lockheed and its partners and the USMC.  It also is a fact that not only the USMC but other nations (e.g. Spain and Italy) will be wanting the F-35B available to replace their carriers - the Harriers won't last forever and there are no other fixed wing options available for their carriers!  Also, unlike the UK, these countries don't have the ability to change their carriers to handle CTOL (at least easily).

I would also factor in the following to this. Secretary Gates is expected to leave office sometime this year so in two years time when this "probation" ends, there will most likely be a different Secretary of Defence with most likely differing views.  Similarly, it is hoped that the world's, and in particular, the USA's, economic situation will be better therefore taking some of the pressure off the program (trust me, the pressure on companies to hit tight cost, schedule and technical targets on this is already pretty extreme).

Regards,

Greg
All hail the God of Frustration!!!