CVF Construction

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10 years 2 months

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For anyone that's intrested there is a pic and a page of Text in Warship Technology http://content.yudu.com/A1gka6/WTOCT09/resources/index.htm?referrerUrl=http%3A%2F%2Fwww.rina.org.uk%2Fwt.html if it's not on the correct page then goto page 6. Are you suprised it's not a British ship, i live on the clyde and if you watch the ships go by few are British owned or flagged, hell if you look at the Shipping AIS system there are far far far more foreign ships. Just the way that the maritime industry in the UK has been attacked and neglected by Government, Sea Blindness is a dangerous thing and one day it will come back to bite us in the backside. Btw, F-35 if you can get pics post them if you can:) we would be most thankfull.

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10 years 5 months

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Has anyone got any progress on CVF to report? I have been reading about CVN USS Gerald Ford and it has a new reactor to provide the extra power needed to power the EMALS. The Nimitz class cannot be refitted with EMALS as the cannot generate enough power for them. This got me thinking about CVF and whether it has enough spare power production capacity to power to EMALS and modern arrestor gear. (i don't know if arrestor gear uses electricity) The CVF design has the upgrade potential built into it for catapults and arrestor gear but would it require some kind of extra power generation turbine or does the current units have enough spare capacity? Maybe the design has been built for steam catapults only i don't know. I don't know how much power the current EMALS require but seeing as Nimitz class can't use them i guess it's alot. Maybe in the future EMALS will be developed to require less electricity to operate? Has the French design of CVF been built to be able to use EMALS? I thought it was going to be built with pretty much the same engines as CVF and operate steam catapults. This got me thinking about the arrestor gear and the forces that must be put through it when an aircraft hooks on. Wouldn't be fantastic if the energy absorbed from an aircraft landing could be turned into electricity and stored and be enough to power an EMAL for take off. Probably not possible but i think that if you could harness the energy of the arrested landing and turn it into electricity it would be a substantial amount. While looking into the arrestor gear on USS Gerald Ford CVN-78 it is new and will operate by using electromagnets to stop the aircraft instead of the current hydraulic system. The Advanced Arrestor Gear (AAG) seems like it would be easier to generate electrical power from it. In defence it often feels as if Britian its technological ability and numbers of ships slip through its fingers. Dr StrangeLove the former head of MI6 was on the radio saying how the current government has really stretched the UK in defence matter like budget etc. I'm finally glad someone is standing up for defence.

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13 years 10 months

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Has anyone got any progress on CVF to report? I have been reading about CVN USS Gerald Ford and it has a new reactor to provide the extra power needed to power the EMALS. The Nimitz class cannot be refitted with EMALS as the cannot generate enough power for them. This got me thinking about CVF and whether it has enough spare power production capacity to power to EMALS and modern arrestor gear. (i don't know if arrestor gear uses electricity) The CVF design has the upgrade potential built into it for catapults and arrestor gear but would it require some kind of extra power generation turbine or does the current units have enough spare capacity? Maybe the design has been built for steam catapults only i don't know. I don't know how much power the current EMALS require but seeing as Nimitz class can't use them i guess it's alot. Maybe in the future EMALS will be developed to require less electricity to operate? Has the French design of CVF been built to be able to use EMALS? I thought it was going to be built with pretty much the same engines as CVF and operate steam catapults. This got me thinking about the arrestor gear and the forces that must be put through it when an aircraft hooks on. Wouldn't be fantastic if the energy absorbed from an aircraft landing could be turned into electricity and stored and be enough to power an EMAL for take off. Probably not possible but i think that if you could harness the energy of the arrested landing and turn it into electricity it would be a substantial amount. While looking into the arrestor gear on USS Gerald Ford CVN-78 it is new and will operate by using electromagnets to stop the aircraft instead of the current hydraulic system. The Advanced Arrestor Gear (AAG) seems like it would be easier to generate electrical power from it. In defence it often feels as if Britian its technological ability and numbers of ships slip through its fingers. Dr StrangeLove the former head of MI6 was on the radio saying how the current government has really stretched the UK in defence matter like budget etc. I'm finally glad someone is standing up for defence.
Stabilizers were delivered to Roysth. http://www.mod.uk/NR/rdonlyres/9FFB2F4E-116E-44ED-914D-A1A35C56FAF6/0/desiderIss19forWeb.pdf In regards to the huge electrical loads imposed by EMALS it would be possible to switch out the MT-30 and replace them with GT with more powerful versions. One of the Joys of IEP is that more possible than previous designs

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11 years 10 months

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I believe CVF has space for steam generators or extra electrical generators if they need to be fitted with catapults.

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10 years 5 months

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I doubt the CVF's were designed with steam cats ever in mind for use. If they still need to use steam cats by the time when they expect the conversion from STOVL to CATOBAR to take place (about mid-life so 25 years time) then the US must be screwed. If it takes them another 25 years to get EMALS working their new CVNs will be impotent. I'm sure that they wouldn't be lauding up the CVFs adaptability without thinking of actually being able to install EMALS, it will have gone past the basic level of being able to physically fit it into the available space.

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10 years 9 months

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Aren't the CVF's "fitted for but not with" an additional pair of MT30's?
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I think so. If what I read is correct, there is space for additional gas turbines, which were omitted on cost grounds, & if electric catapults were to be installed in a refit, more turbines could be fitted at the same time.

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10 years 2 months

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Really? I didn’t know that could you point me to a source please as that’s pretty darn interesting. I’m not saying I don’t believe you but it comes as news to me although I don’t see why not after all it is a massive hull with growth margins. Would adding more turbines in anyway increase the top speed, I would imagine not due to the sizing of the electric motors driving the shafts. Furthermore adding more turbines would eat a fair chunk out of the range and time on station so would require more replenishment. If there is room for additional turbines would it have been anywhere near a good idea to install 4 WR-21’s instead of 2 MT-30’s the reason I say this is lower fuel burn, more redundancy and commonality with the Type 45. The commonality would allow the same people to maintain the turbines and the same spares stock to be used across the fleet. If needed later the WR-21’s could be replaced with the MT-30 giving a massive boost in power. The downside would be increased acquisition cost and possibly fuel burn when at the higher end of the speed range and power need but this would be rare as most of the time they would be cruising along.
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Here are some calculations for a hypothetical Typhoon N, navalized version of EF. Calculations are based on minimum speed demonstrated this Summer in Zeltweg and Craig Penrice's testimony of Typhoon's acceleration. Also, I've "fattened" Typhoon N to 12t empty weight, due carrier requirement airframe/gear adjustments. Vt = take off speed V+ = take off speed + carrier speed (25 kts) R = runway length Mtow (Typhoon N) = 25500 kg Vstall (Mtow) = 168 kts R=150 m Vt=110 kts V+=135 kts R=200 m Vt=126 kts V+=151 kts R=250 m Vt=141 kts V+=166 kts This calculation is given without ski-jump and it seems Typhoon N should be able to handle Mtow take off even from the half runway length (~150m), which is HMS Queen Elizabeth's standard operating distance (according to promo films), using standard EJ200 engines. On the other hand, from full runway (~250m), Typhoon N could be launched even if the carrier is stationary and there's no wind. Does anyone know, if the HMS Queen Elizabeth's layout has been nailed down, or is still under consideration? Thx.

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10 years 2 months

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Cola very nice post interesting indeed any idea what effect thrust vectoring would have on takeoff performance? I would hope for a small improvement or increase in safety would be possible. Furthermore regarding the CVF deck layout I would imagine the minor details are subject to change rather than set in stone and as we all know built with change in mind so should be flexible enough. Changing it around would cost money but should not be a problem as the deck is a long way off from being built and fitted out.
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10 years 6 months

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Cola very nice post interesting indeed any idea what effect thrust vectoring would have on takeoff performance? I would hope for a small improvement or increase in safety would be possible.
None (possibly minor), since the plane leaving ski-jump doesn't have problems with lift-off, the way it'd have on a straight runway. Moreover, I didn't calculate direct-force control (which Rafale and Gripen normally utilize and is far more important than TVC), because I didn't see it being operated on EF up to date, but I guess FCS isn't complete yet, so we may expect further 25-30 kts of approach/take off speed reduction. Thx, for CVF response. I just wanted to make sure that I was using the right blueprint, since there was several floating around...So, is this the correct version?
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Profile picture for user swerve

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Really? I didn’t know that could you point me to a source please as that’s pretty darn interesting. I’m not saying I don’t believe you but it comes as news to me although I don’t see why not after all it is a massive hull with growth margins. Would adding more turbines in anyway increase the top speed, I would imagine not due to the sizing of the electric motors driving the shafts. Furthermore adding more turbines would eat a fair chunk out of the range and time on station so would require more replenishment. If there is room for additional turbines would it have been anywhere near a good idea to install 4 WR-21’s instead of 2 MT-30’s the reason I say this is lower fuel burn, more redundancy and commonality with the Type 45. The commonality would allow the same people to maintain the turbines and the same spares stock to be used across the fleet. If needed later the WR-21’s could be replaced with the MT-30 giving a massive boost in power. The downside would be increased acquisition cost and possibly fuel burn when at the higher end of the speed range and power need but this would be rare as most of the time they would be cruising along.
I can't find my original source for this, but there's an essay on CVF propulsion, & the route to the final configuration, on Richard Beedalls site, here. Up to his usual standards. He does not say that there is still space allocated for additional GTs, but it does seem possible. According to him, the final propulsion configuration was fixed by Spring 2005, at two MT30s & 4 diesels, but -
By Summer 2004 sources were indicating that the CVF machinery was likely to use two Rolls Royce MT30 gas turbines alternators sets (although if required three or even four could still be fitted)
It could be that the option for additional GTs I read about was based on a misunderstanding, & that the option was closed off sometime after Summer 2004. It would be nice to have clarification.

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10 years 2 months

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Thanks for the reply about the Eurofighter, the only effect I know that the TVC would have is to lower approach speeds slightly but apart from that I have no idea how it could be utilised in regards to landing and takeoff. That deck layout looks about right and it should be reliable as it is an official MoD image I will have a look at the Navy Matters website to check. The major things like the deck lifts, weapon lifts and island positions would I’m reasonably confident, be fixed as these would have wider effects than moving around fuel, fire fighting systems and electrical wiring and small equipment. Thank you Swerve I’ll give that essay a read to see what I can discover. I would hope there is additional room within the hull as the design is supposed to have large margins for growth. Growth especially on an all electric ship is logical as power will be an ever increasing demand as different sensors and weapons are added.
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13 years 1 month

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As we are into calculations for takeoffs, I thought this might be of use. I get asked to explain the ski jump regularly, since many seem unable to grasp the point. When you leave the end of the ramp, you will only be at about 80 knots and you aren't actually flying yet. But you are still accelerating and the ramp has converted some of your forward momentum into vertical thrust so you gain altitude whilst you are accelerating. Before you reach the top of the arc you will have reached true flying speed (about 130knots, and you will be at about 200ft). If there is a problem on takeoff such as engine failure, the pilot will have several extra seconds to decide what to do (eg eject) compared to the flat trajectory of a catapult launch. In the latter case a pilot coming off the end of a catapult with a serious malfunction will be lucky to have two seconds to join the Martin Baker appreciation society. EMALS offers the possibility of combining the two systems, gaining the extra safety of the ski jump and the extra payload of the catapult...;)
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Vt = take off speed V+ = take off speed + carrier speed (25 kts) R = runway length Mtow (Typhoon N) = 25500 kg Vstall (Mtow) = 168 kts R=150 m Vt=110 kts V+=135 kts R=200 m Vt=126 kts V+=151 kts R=250 m Vt=141 kts V+=166 kts
I don't get the math. 135 kts << 168kts, so how could Typhoon take-off in 150m??? You also need to add at least 15 knots safety margin to Vstall, so that would implies that at MTOW V+ would have to be around 190kts.
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I don't get the math. 135 kts << 168kts, so how could Typhoon take-off in 150m??? You also need to add at least 15 knots safety margin to Vstall, so that would implies that at MTOW V+ would have to be around 190kts.
You have missed two points. 1) No ramp effect added to that speed. Apparently, 12° ramp adds quite a bit to maximum allowed take off weight, or effectively increases speed, which ever you like better. 2) No DFC, which will further reduce operating speed, as put in second post. So yes, there's a ~33 kts difference margin, but DFC + ramp should offset this by more than enough margin to allow safe take off.
Profile picture for user Stan hyd

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http://img31.imageshack.us/img31/8493/rampu.png lets try this :P

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citation: United Kingdom Announces Approval of Third F-35B Joint Strike Fighter Purchase The Joint Combat Aircraft (JCA) program has announced that the United Kingdom has received financial approval to purchase its third Lockheed Martin (NYSE: LMT) F-35B Lightning II operational test aircraft, reinforcing the U.K.'s continued commitment to the Joint Strike Fighter program's upcoming Operational Test and Evaluation (OT&E). "The U.K. this week received financial approval to go ahead and purchase the third U.K. STOVL OT&E aircraft that is planned within LRIP 4. Given the extremely tight financial climate in the U.K. government and the consequent impact across public spending, especially defence, this is a significant achievement," said Air Commodore Graham Farnell, the U.K.'s Joint Combat Aircraft Team head. "I believe it reflects well upon the JSF program and it is a measure of the confidence that the U.K. has in both the F-35 Lightning II and the program to deliver this capability." This approval follows recent F-35 down-select or procurement commitments by Australia, Norway, the Netherlands, Italy and the United States. The strength of the F-35 business case has enabled program suppliers to obtain the capital financing needed to recapitalize the industrial base and produce the F-35 in high quantities over the next 30 years. "The United Kingdom's participation in F-35 Operational Test and Evaluation, and the associated commitment to purchase F-35s in early production lots, help ensure production stability as we move from the current assembly rate of one aircraft per month to our goal of one per day," said Matt Maxwell, Lockheed Martin director for F-35 Low Rate Initial Production. The U.K. has invested $2 billion in the F-35's development - the largest contribution among the program's eight partner nations. More than 100 British companies are involved in the program, including BAE Systems, which produces the aircraft's aft fuselage and tails; Rolls-Royce, developer and manufacturer of the shaft-driven lift fan and other propulsion components for the F-35B STOVL variant; and Martin Baker, maker of the jet's ejection seats. The F-35 is a supersonic, multi-role, 5th generation stealth fighter. Three variants derived from a common design, developed together and using the same sustainment infrastructure worldwide, will replace aircraft in at least 13 services for nine nations initially, making the Lightning II the most cost-effective fighter program in history. Headquartered in Bethesda, Md., Lockheed Martin is a global security company that employs about 140,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services. The corporation reported 2008 sales of $42.7 billion. source http://www.prnewswire.com/news-releases/united-kingdom-announces-approval-of-third-f-35b-joint-strike-fighter-purchase-79922722.html

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10 years 5 months

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Any idea's on where the 3 LRIP F-35 STOVL Joint Strike Fighters will be based? Are these aircraft the final production models or are they still development aircraft? Have LM managed to get the weight down in the B model? I imagine improvements will come as production gets going and the things are identified. This is good news i guess for the carriers. Who is going to own these aircraft? Is the RAF or FAA or some other government organisation? I can't see a delivery date on the above text so hopefully 2010 would be great. I can't wait to see these aircraft up close or in the sky. Good news for the UK, I think the government knows it can't pull out of this one as there is so much riding on these. The parts the UK companies are making are going to generate a lot more cash than these aircraft will cost, also the carriers can't run without them. So the government could look at it as the UK will be getting the aircraft for free and will probably make more money than the aircraft could ever cost. The tax revenue will run into millions more than the cost of the aircraft. All in all a good deal for the UK.

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10 years 5 months

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I thought i would add in some interesting pictures of JSF i found on Richard beddall Navy matters site. This site is wonderful for Navy stuff. http://frn.beedall.com/ What we could of ended up with, BAE and Mcdonnell Douglas Variant. ( not many pictures of this floating around) Personally i like it. http://frn.beedall.com/images/jast-md-ng-bae.jpg Will we see this one day soon? The F-35 operating from the Invincible class carriers deck. i'm guessing we will see this for trials now the 3 aircraft are on order. http://frn.beedall.com/images/f35b-uk-2006.jpg It seems like for the harrier upgrade there was 2 seperate projects i think. I haven't seen much about what these aircraft was going to be like or have on them. Quite an interesting development i think. There is the Harrier 3 here from around the 1990's. http://frn.beedall.com/images/harrier3.jpg And the Super harrier that seems to have been thought of sometime in the 80's. Probably as the success the harrier had in Falklands some people thought lets go crazy. http://frn.beedall.com/images/superharrier.jpg Has anyone got any pic's of the CVF development. How's the super block building getting along. I've not been down to roysth recently but i'm not sure there is any activity going on there anyway with CVF. Maybe some ships in Refit to look at.