UK MOD in a muddle over F-35C

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Unread post17 Aug 2017, 16:08

It is official CHUTER is another Fwit SPELla of 'Lightening' for Fsake. Either that or the editor of story is a MORON but hey.
HMS Queen Elizabeth makes an early appearance at its home port
16 Aug 2017 Andrew Chuter

"...The warship entered the naval base, south of England, sooner than expected after the Royal Navy and the industry alliance that built the carrier changed the original plan and brought HMS Queen Elizabeth into Portsmouth midway through the sea trials now underway rather than when the tests were expected to be completed later this year.

Engineering work was originally planned to be undertaken at Rosyth Dockyard, Scotland, where the warship was built and then the sea trials got underway June 27, will now be conducted at the naval base ahead of the warship heading out for a second phase of trials.

About 12 days into the trials, the warship berthed at the deepwater port of Invergordon, Scotland, spending two weeks for a planned replenishment and refueling and the resolution of engineering issues. The ship’s propulsion system was also checked by divers after the HMS Queen Elizabeth hit debris, possibly fishing nets, during the trials in the North Sea.

After resuming trials, the aircraft carrier returned to Invergordon earlier this month ahead of sailing to Portsmouth....

...The ships will not both be operated at once. The British do not have the manpower, money or aircraft to do that, but they will enable the Royal Navy to operate a single carrier continuously....

...The Royal Navy will operate the F-35B Lightning II short takeoff and vertical landing strike jets and Merlin airborne early warning helicopters from the warship.

The U.K. has 11 F-35B’s delivered so far. By the end of this year, all 14 jets so far ordered will be delivered. Flight trials from the carrier’s deck are on track to begin next year, with initial operational capability expected in 2020 and full capability three years later.

The British government said in its 2015 strategic defence and security review that it would buy at least 48 of the F-35B version of the strike jets and committed to eventually purchase 138 Lightening II, without specifying the types.

The F-35B will be operated by the Royal Navy and the Royal Air Force, but there have been hints the RAF could eventually be equipped with the F-35A version used by the U.S. Air Force."

Source: http://www.defensenews.com/naval/2017/0 ... home-port/
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Unread post17 Aug 2017, 16:53

BACK IN BUSINESS
Sep 2017 Tim Ripley

"HMS QUEEN ELIZABETH Britain’s newest and biggest aircraft carrier, HMS Queen Elizabeth (R08), is approaching the end of a first phase of sea trials. Tim Ripley visited her in Rosyth dockyard and reports on the UK’s return to the aircraft carrier business....

...fast jet trials. What is termed a ‘technology insertion period’ will take place to install the equipment needed to operate helicopters and F-35Bs on a sustained basis. This includes the F-35B’s computerised Autonomic Logistics Information System (ALIS), which is essential to operating the Lightning II from the ship.

“In 14 months’ time, we will be on the eastern seaboard of the US to embark the first Lockheed Martin F-35B Lightning II,” Kyd said. “Then we will be carrying out hundreds of landings and take-offs under different wind and light conditions.” British and US aircraft and personnel from the F-35 Integrated Test Force based at Naval Air Station Patuxent River, Maryland, will be at the heart of these trials. For reasons of national prestige, the first F-35B to land on HMS Queen Elizabeth will be a British jet, piloted by a British test pilot. The MOD is expecting this work to be carried out in autumn 2018.

Senior officers onboard HMS Queen Elizabeth are confident there will not be any major problems putting the F-35Bs onto the carrier. Many of the aircraft’s landing controls are automated and they have been repeatedly practised in simulations.

A lot of the early work will involve proving that the computer simulations of flight operations are valid and will look at the environmental impact of operating the F-35B over the deck. The carrier deck will have to cope with 1,500-degree centigrade [this is just insane but crap memes never die - they just get repeated] heat from the F-35B’s engine. The original coating did not pass muster and a new Thermal Metal Spray System, consisting of a metallic compound of aluminium and titanium, has since been applied to important parts of Queen Elizabeth’s flight deck. One officer described this as a “science project” because until a jet actually tries to land on the ship no one will know what will happen. “We are pretty confident the deck is not going to burst into flames as soon as a jet tries to land,” he said. “What we are interested in is working out how long the coating will last and what type of maintenance regime we need to put in place to maintain its effectiveness.”

The flight trials off the east coast of the US will involve test-instrumented aircraft to collect the required data, rather than operational examples from No 617 Squadron at MCAS Beaufort, South Carolina. The first batch of pilots and ground personnel are in training there ahead of the unit’s return to RAF Marham, Norfolk, next summer. By the end of 2018, nine aircraft should be at Marham, which will enable initial operational capability (IOC) to be declared by the squadron.

In the summer/autumn of 2019, No 617 Squadron is expected to embark on HMS Queen Elizabeth for a series of squadron-level operational test and evaluation exercises, to prove the warfighting tactics and procedures needed to operate a significant number of F-35Bs from the ship. The following year, the operational envelope will be pushed further still via a full task-group-level operational trial that will bring together a squadron of F-35Bs, anti-submarine and airborne early warning Merlins, surface warships, supply vessels and shore-based air power. If successful, this test will allow the Royal Navy to declare carrier strike IOC....
&
...Joint Force Harrier was a combined organisation containing distinct Royal Navy and Royal Air Force flying squadrons, albeit with teams of dark and light blue personnel. The current Lightning Force is a truly integrated organisation, with RAF and RN personnel intrinsically mixed together within squadrons. Some 58% of the force will be RAF and 42% will be RN, with both services contributing commanders at all levels on a merit basis. This could ultimately lead to No 617 Squadron or No 207 Squadron – the Operational Conversion Unit (OCU) – being led by a naval aviator or 809 NAS being commanded by an RAF officer. Unlike US Navy aircraft carriers or the previous British carriers, there will not be a dedicated Commander Air Group, or CAG, to control all the aircraft and personnel embarked on HMS Queen Elizabeth or Prince of Wales. Ad hoc command staff will either be embarked on the ship to plan air campaigns or will issue air tasking orders (ATOs) from a headquarters ashore. When serving in the amphibious operations role landing Royal Marines, Joint Helicopter Command (JHC) is expected to deploy a command team onto the carriers to direct rotary-wing missions....."

Source: AirForces Monthly Magazine September 2017 #354
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Unread post18 Aug 2017, 00:51

Holy Crap! 1500°C! Last I heard that lie it was Farenheit. It just keeps getting hotter and hotter and...

We colonists brew cold, iced tea. The Brits would do well to brew thousands of gallons of the stuff... then run it through heat exchanger tubes embedded in the deck solst her majesty's deck doesn't melt. After a couple Lightening landings around 3pm... they'll have all the hot tea they need for afternoon tea @ 4pm... :doh:
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Unread post18 Aug 2017, 22:00

A couple of articles either in this thread or elsewhere make it clear the STOVL Mode 4 (no afterburner) Vertical Landing does NOT create AfterBurner temperatures SADLY usually quoted to malign something or other about melt deck/F-35Bs.

I'll find the links soon enough MEANWHILE back at the OK Corral QE CVF etc. etc.... (no subscription so not much text).
UK details F-35B carrier trials
17 Aug 2017 Tim Ripley

"The UK’s Queen Elizabeth aircraft carrier is to spend eight weeks off the east coast of the United States carrying out flight trials next year with Lockheed Martin F-35B Lightning II Joint Strike Fighters embarked for the first time. Royal Air Force (RAF) Squadron Leader Andy Edgell, the UK’s lead test pilot for the new carrier’s First of Class Flight Trials (FOCFT), told Jane’s on 16 August that the flight trials during the fourth quarter of 2018 would build up to “maximum rate tasking” for two embarked aircraft, four pilots and the ship’s company.

In the first briefing detailing the FOCFT, Sqn Ldr Edgell described the event as “the Super Bowl of flight tests – it is the definition of development testing … We are taking a brand new aircraft on to a brand new class of carrier”, he said. “This is a huge deal for us.”

The FOCFT project will start with the carrier’s deck crew getting familiar with the jets, their noise and how they move around the deck, said Sqn Ldr Edgell. The intensity of the trials will then ramp up until aircraft and crews are conducting multiple flight cycles – launching and recovering jets during three to four hours long blocks – each day. These will involve day and night flying. Sqn Ldr Edgell said the aim was to get as much out of the trials as possible. “We have a finite period and will aim to make as many flights as we need,” he said...."

Source: http://www.janes.com/article/73179/uk-d ... ier-trials
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Unread post18 Aug 2017, 22:09

Some info about deck/concrete temps during an F-35B VL as founded in - just the troof - nuttin' but the troof, ma'am.

600 degrees Fahrenheit = 316 degrees Centigrade - Search the F-35 forum for original posts with text link(s) below.
Shipshape Amphibious ship upgrades vital to JSF and MV-22 deployments
13 Oct 2014 Michael Fahey; AVIATION WEEK & SPACE TECHNOLOGY; DEFENSE TECHNOLOGY INTERNATIONAL

"...The F-35B creates 10-20 sec. of thermal input - 400-500F exhaust - during landings, Navy documents show..."

Source: 13 Oct 2014 AVIATION WEEK & SPACE TECHNOLOGY; DEFENSE TECHNOLOGY INTERNATIONAL

JOINT STRIKE FIGHTER Boeing X-32 - Lockheed Martin X-35
23 April 2001 Geoffrey Buescher

“...Lockheed Martin STOVL Lift Fan System-
...Lift fan has two stages, pressure ratio of 2. Uses 27,000 – 28,000 hp from 70,000 – 80,000 produced by turbine.

• Using lift fan instead of hot flow reduces flow velocity by 30%, lowers [hot exhaust] temperature by 250 deg F; lift fan produces about 18,000 lb thrust.

• Lift fan adds 4,000 lb to airframe, but lifting capacity of STOVL is increased by much more — claims of 60% above direct thrust approach. For CTOL and CV versions, extra space otherwise used for lift fan is used for fuel & avionics.

• Cold [350 deg F approx.] flow from lift fan protects inlet from hot gas ingestion...”

Source: http://www.dept.aoe.vt.edu/~mason/Mason ... escher.pdf (0.7Mb)

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Unread post18 Aug 2017, 23:49

The reasons HMS Queen Elizabeth has two islands
14 Aug 2017 SaveTheRoyalNavy

"...Redundancy and separation can be good
In a moment of inspiration back in 2001, an RN officer serving with the Thales CVF design team developing initial concepts for what became the Queen Elizabeth Class, hit upon the idea of separate islands. There are several advantages to this design but the most compelling reason for the twin islands is to space out the funnels, allowing greater separation between the engines below. QEC has duplicated main and secondary machinery in two complexes with independent uptakes and downtakes in each of the two islands. The separation provides a measure of redundancy, it increases the chances one propulsion system will remain operational in the event of action damage to the other. Gas turbine engines (situated in the sponsons directly below each island of the QEC) by their nature require larger funnels and downtakes than the diesel engines (in the bottom of the ship). The twin island design helps minimise their impact on the internal layout....

...The twin island design has several other benefits. Wind tunnel testing has proved that the air turbulence over the flight deck caused by the wind and the ship’s movement, is reduced by having two islands instead of one large one. Turbulent air is a hindrance to flight operations and aircraft carrier designers always have to contend with this problem....

...Flyco – aft
The QEC aircraft control position, known as flyco is a major change in design philosophy. Instead of being just an appendage to the navigation bridge it has been designed in partnership with Tex ATC Ltd, one of the world’s leading providers of military and civilian airfield control towers. By siting the Flyco separately, it can be positioned in the optimum place to view aircraft as they approach the ship for landing. This is the moment when the pilot requires most help from the ship and a dedicated aircraft controller sitting in Flyco (usually a former pilot) can help talk the plane down if needed. The QEC flyco projects out from the aft island and has enormous 3-metre tall windows with providing a 290º view over the flight deck. Such tall windows allow a good view of high flying aircraft for all, including for the personnel sitting in the small raised gallery at the back of the Flyco. In some older ships, the cramped flyco position looked like an afterthought it was sometimes necessary to get right up close to the small windows to see high flying aircraft.

Source: http://www.savetheroyalnavy.org/the-rea ... o-islands/
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Unread post18 Aug 2017, 23:59

Spaz, we are almost two decades beyond X-35. X-35 is not F-35B.
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Unread post19 Aug 2017, 00:33

quicksilver wrote:Spaz, we are almost two decades beyond X-35. X-35 is not F-35B.


Uhh, yeah, but...

What's your point? The X-35 demonstrated the advantages of the lift fan concept. The actual numbers related to the F-35B exhaust will be different, but not that much different. The video is from a 2010 lecture, so the F135-PW-600 had been around for several years. The 2014 document reference stated that the thermal exhaust temps are between 4-500°F, far less than the 1000°F spall temperature noted by Bevilaqua in the video. So... I'm not following what you are trying to say?
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Unread post19 Aug 2017, 01:18

The X-jet proved the concept; the 'B' is heavier -- the laws of physics prevail. More weight requires more lift. If we're talking propulsion system lift that means more thrust. While there have been significant improvements in engine technologies that produce more thrust with less consequential heat, at some point you have to 'turn up the wick' so to speak.

Now we move forward to the generally dismal reporting on F-35; many of these guys and gals dont know the difference between a 'C' at the end of the number or an the 'F'. If confused or unclear, they dont even ask, they report (i.e. inject into the world of the internet) something as fact that is not even close to reality. In many cases, there is no intent to mis-represent the reality, they simply dont know enough to ask the right questions. The inattention to semantics often leads reporters down this path; e.g. they don't know the difference between the 'fan' (ie the lift fan) and the main engine (which happens to be a 'turbofan').

The lift fan (which of its own mechanism burns nothing) is 'cold' air -- 'cold' for a thrust/lift-producing machine that creates close to 20K# of vertical thrust, but hardly cold for airframes and humans and landing surfaces. The main engine (which does all the combustion) is like many other jet engines -- the stuff it spits out the back is really bleeping 'hot'. Of course, the question is how 'hot'? The answer is both 'more than widely reported' and 'not as much as widely reported' -- reference the lift fan discussion above.

The best 'general' reference for the temperature of the main engine exhaust was provided by the then-CMC (Commandant of the Marine Corps) when he stated something to the effect that the exhaust temps of F-35B were/are very similar to Harrier (which, btw, hasnt been melting flight decks for a few decades). Harrier EGT -- measured at the thermocouple -- limits at 800C in short lift wet. By the time the exhaust air travels few feet and makes a few turns it is going to be something less than that. 800C is 1472F; that means that the exhaust that impinges on the deck at the max temp the Pegasus accommodates is something less than 1472F -- which (btw) doesnt melt anything during a VL aboard ship. So, by extension, neither does F-35B. The issue with F-35B is that its empty weight is roughly 2X that of Harrier. If I impart similar thermal stress on a structure with 2x the weight, there will be a long term consequence to the underlying structure. The Commandant wasnt lying (are you paying attention Bill...?); it's not about the temps.

Hope that helps. There is a world-record thread around here somewhere on this stuff. Spaz can help.
Last edited by quicksilver on 19 Aug 2017, 09:41, edited 3 times in total.
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Unread post19 Aug 2017, 01:22

steve2267 wrote:
quicksilver wrote:Spaz, we are almost two decades beyond X-35. X-35 is not F-35B.


Uhh, yeah, but...

What's your point? The X-35 demonstrated the advantages of the lift fan concept. The actual numbers related to the F-35B exhaust will be different, but not that much different. The video is from a 2010 lecture, so the F135-PW-600 had been around for several years. The 2014 document reference stated that the thermal exhaust temps are between 4-500°F, far less than the 1000°F spall temperature noted by Bevilaqua in the video. So... I'm not following what you are trying to say?


Lift fan or main engine? How do you know? You don't...you are reliant on the reporting, which is erroneous.
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Unread post19 Aug 2017, 01:37

The video is about the temperature recorded at/on the concrete so one may imagine at some other recording points between there and the actual exhaust nozzle the temperature will be higher and AFAIK the video is about the F-35B.
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Unread post19 Aug 2017, 01:52

I get it Spaz -- it's Dr B talking. What I'm telling you is that it's X-jet assumptions and modeling. Go find a credible empty weight for the STOVL X-jet; it was a feather compared to F-35B. It didnt have to carry sensors, weapons, weapons system avionics, as much fuel, or as much structure for a specified operational life.

However, the bottom line is that the exhaust temps for F-35B aren't even close to prohibitive (in spite of attempts by some to claim otherwise).
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Unread post19 Aug 2017, 02:26

Back in the mists of time 'Dragon029' posted a video of the entire Dr. Bevilacqua lecture. At minute 56 the sim of the F-35B VL impinging on concrete to satisfy USMC it is not stated yea or nay about what aircraft it is so I say it is the F-35B.

https://youtu.be/u-cfy-k_8ew?t=3332 viewtopic.php?f=22&t=21797&p=362550&hilit=version#p362550

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Unread post19 Aug 2017, 04:13

quicksilver wrote:I get it Spaz -- it's Dr B talking. What I'm telling you is that it's X-jet assumptions and modeling. Go find a credible empty weight for the STOVL X-jet; it was a feather compared to F-35B. It didnt have to carry sensors, weapons, weapons system avionics, as much fuel, or as much structure for a specified operational life.

However, the bottom line is that the exhaust temps for F-35B aren't even close to prohibitive (in spite of attempts by some to claim otherwise).


X-35B empty weights:

22,500lbs - https://www.globalaircraft.org/planes/x-35_jsf.pl
22,000lbs - wikipedia (probably for the -A variant. The globalaircraft.org webpage also stated 22,000lbs for the -A).
Weights: X-35A, 26 500 lb; X-35B, 30 697 lb; X-35C 30 618 lb (Ref. 4) (http://www.dept.aoe.vt.edu/~mason/Mason ... escher.pdf)

Yes, the X-35B was lighter than the F-35B, but "a feather compared to the F-35B"? I don't see it. But the empty weight of the aircraft isn't really the issue here -- the thrust of the powerplant is. LM flew the X-35's with a modified F119:

The X-35B features a unique propulsion system in which a drive shaft from the Pratt & Whitney JSF119-611 engine (common to all Lockheed Martin JSF variants) turns a counterrotating lift fan that produces cool-air lifting force during STOVL operations. The Rolls-Royce fan, actuated by a clutch that can be engaged at any power setting, works in concert with an articulating rear duct and under-wing lateral-control nozzles to lift the aircraft with nearly 40,000 pounds of vertical force. Because the fan amplifies the engine's power, the engine is able to run cooler and with less strain, increasing reliability and extending service life. The lift fan provides the propulsion system with about 15,000 pounds more thrust than the engine alone could generate.

Reference: news.lockheedmartin.com/2001-07-16-Lockheed-Martin-JSF-X-35B-Makes-History-After-Vertical-Landing-from-Wingborne-Flight-Short-Takeoff?asPDF=1


So, irrespective of the actual weight of the X-35B vs the F-35B, the X-35B F119-611 engine was capable of putting out "nearly" 40,000lbs of thrust in the vertical mode. The F-35B F135-PW-600 is around 41-42,000lbs and change in Mode 4. This thrust differential (F119 -> F135) is well under 10%. Since another way to get more thrust out of a turbofan is to increase mass flow, I could easily see increased mass flow rate due to fan section changes accounting for the thrust differential compared to the F119 -- rather than having to jack the turbine / combustion temps through the roof. The F135 has been already been described as having a much higher bypass ratio compared to the F119.

Even if the video from Dr Bevilaqua's lecture was from LM modeling an X-35B with the F119 and showing 400-600°F on the ground during a VL, I do not see the F-35B (F135-PW-600) being a factor of two hotter than that F119-611. Spaz also points out that modeling video could very well be of an F-35B anyway. IMO, LM (possibly Dr. B himself) modeled the hell out of the F-35B (and the X-35B), and the videos of Dr. B's presentation accurately reflects what LM calculated.

From an engineering viewpoint, considering Dr. Bevilaqua's description of the combined cycle operation of the F135, I just do not see the exhaust temps going from ~500°F to ~14-1500°F. Is TEG still around? I'd be interested in his opinion on this topic.
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Unread post19 Aug 2017, 09:21

Dr B is talking about heat transfer -- the concrete temp not the exhaust temp. 3000# is alotta weight on a jet you have to lift with propulsion alone.

Trust me, the main engine exhaust -- even on the X-jet -- is not in the 500F range suggested above.
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