EMALS & JPALS for the JSF

Discuss the F-35 Lightning II
  • Author
  • Message
Offline
User avatar

blindpilot

Forum Veteran

Forum Veteran

  • Posts: 938
  • Joined: 01 Mar 2013, 18:21
  • Location: Colorado

Unread post21 Oct 2017, 06:16

neptune wrote:...

....they'll need a nuke to run it and that is not their strong suit!
:)


The Vishal Class that is installing the EMALS is to be a nuke ship.

FWIW,
BP
Offline

wolfpak

Enthusiast

Enthusiast

  • Posts: 67
  • Joined: 12 Jan 2014, 19:26

Unread post21 Oct 2017, 16:53

Nuclear powered carriers came into being in part to address the issues of steam production and catapults. Oil fired carriers could only launch a number of aircraft before needing to rebuild steam pressure in the system. The nukes generate more heat and can make more steam. Hence they could launch without taking pauses. With the advent of EMALS you don't need as much steam volume because you just direct what you make thru turbines that drive the ship and produce electric power. Catapults are a steam hog taking a lot of volume due to loses in the piping and the one shot use in the piston/cylinder itself. That steam used to generate electricity is condensed and recycled in the system not expended as in traditional catapults so the reactors can be smaller and more efficient.
EMALS uses ship's electric power to run a motor generator coupled to a flywheel to generate the on demand (pulsed) power needed to operate that cats while demanding only continuous power from the ship's plant. Think of them as a electromechanical capacitor storing energy for when needed. That in itself decreases reactor size because you now don't have peak demands but an average power use.
Offline

tincansailor

Forum Veteran

Forum Veteran

  • Posts: 637
  • Joined: 05 Jul 2015, 20:06

Unread post21 Oct 2017, 19:12

[
quote="wolfpak"]Nuclear powered carriers came into being in part to address the issues of steam production and catapults. Oil fired carriers could only launch a number of aircraft before needing to rebuild steam pressure in the system. The nukes generate more heat and can make more steam. Hence they could launch without taking pauses. With the advent of EMALS you don't need as much steam volume because you just direct what you make thru turbines that drive the ship and produce electric power. Catapults are a steam hog taking a lot of volume due to loses in the piping and the one shot use in the piston/cylinder itself. That steam used to generate electricity is condensed and recycled in the system not expended as in traditional catapults so the reactors can be smaller and more efficient.
EMALS uses ship's electric power to run a motor generator coupled to a flywheel to generate the on demand (pulsed) power needed to operate that cats while demanding only continuous power from the ship's plant. Think of them as a electromechanical capacitor storing energy for when needed. That in itself decreases reactor size because you now don't have peak demands but an average power use.

[/quote]

Good job. Very concise exposition. You explained it very well, so even non technical readers could understand. It's amazing what a steam plant can put out, but every technology has it's limits, and the steam catapult has reached that point.
Offline
User avatar

spazsinbad

Elite 3K

Elite 3K

  • Posts: 19235
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post02 Nov 2017, 05:52

Breakthrough to power most advanced jet launch system on China’s second home-grown aircraft carrier
01 Nov 2017 Minnie Chan

"A technological breakthrough in naval propulsion will enable China’s second home-grown aircraft carrier to use the world’s most advanced jet launch system without having to resort to nuclear power, overcoming a huge hurdle in the vessel’s development, military sources said. The development of the integrated propulsion system (IPS) would allow the vessel to be more efficient, allowing more power for an electromagnetic catapult, rather than a less technologically advanced steam-driven catapult launch system, the sources said.

China’s first two carriers, the Liaoning and its sister ship, the Type 001A, are conventionally powered vessels equipped with Soviet-designed ski-jump launch systems. But an electromagnetic aircraft launch system (EMALS) on the Type 002, China’s second home-grown aircraft carrier, would mean less wear and tear on the planes and allow more aircraft to be launched in a shorter time than the ski and steam-catapult systems.

According to a source close to the People’s Liberation Army, China’s Central Military Commission was keen to use EMALS on the Type 002. “[But] the obstacle … was whether a conventionally powered carrier would be able to support EMALS, and now that problem has been solved,” the person, who is close to the PLA’s equipment department, told the South China Morning Post. The solution was provided by a team led by China’s top naval engineer Rear Admiral Ma Weiming, which developed a medium-voltage, direct-current transmission network to replace an earlier system based on alternating current....

...“It wasn’t just a simple switch from alternating to direct current, but a complete overhaul of the energy supply and distribution system – from steam boilers to the energy storage device,” he said. Wang added that in the future, the same technology could be used to launch not just aircraft, but also missiles and satellites, and maybe even power high-speed trains....

...He [Weiming] also said on the sidelines of the annual National People’s Congress in Beijing that China’s EMALS technology was more advanced and more reliable than the system used on the nuclear-powered USS Gerald Ford supercarrier...."



Source: http://www.scmp.com/news/china/diplomac ... nch-system
Attachments
Type002chineseEMALScarrier.gif
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline

sunstersun

Enthusiast

Enthusiast

  • Posts: 79
  • Joined: 12 Jul 2017, 06:50

Unread post02 Nov 2017, 17:31

Man, China's navy is really beasting ahead.
Offline

afjag

Newbie

Newbie

  • Posts: 15
  • Joined: 29 Aug 2017, 23:15

Unread post02 Nov 2017, 17:41

The danger of industrial espionage is that you also steal all of the current flaws and technical design limitations inherent in new systems. :devil:
Offline

tincansailor

Forum Veteran

Forum Veteran

  • Posts: 637
  • Joined: 05 Jul 2015, 20:06

Unread post02 Nov 2017, 19:03

The proof of the pudding is in the eating. It's hard to imagine that with so little effort, they would get a successful operational system, with their first try. They may have stolen a lot of data, but this is apparently a different system then we are using. DC power is a short cut, that has some drawbacks. We have to wait for the 002 to go to sea, and see how well it works out.
Offline

usnvo

Newbie

Newbie

  • Posts: 17
  • Joined: 01 Jul 2015, 18:51

Unread post02 Nov 2017, 19:55

blindpilot wrote:
neptune wrote:...

....they'll need a nuke to run it and that is not their strong suit!
:)


The Vishal Class that is installing the EMALS is to be a nuke ship.

FWIW,
BP


Besides the article being riddled with errors, the comments were even more laughable.

Just for starters, the reactors on the FORD are more compact and efficient than the ones on the NIMITZ class because they weren't designed in the 1960s! They could power steam catapults even better than the reactors on the NIMITZ if that was how they chose to use them. All a reactor does is generate pressurized hot water for the steam converters.

There is absolutely no reason you need a nuclear power plant to run EMALS. The FORD class has 4 26MW SSTGs (they have 4 diesel generators of similar size for backup) to provide electrical power although it is highly unlikely they will ever use all of them at once. An MT-30 GTG puts out something like 35MW of power and can react to changes in load dramatically quicker than the steam turbines on the carrier. 2 MT-30s can provide all the power required for EMALS, the rest of the ship, and then some without even working hard.
Offline

sprstdlyscottsmn

Elite 3K

Elite 3K

  • Posts: 3139
  • Joined: 10 Mar 2006, 01:24
  • Location: Phoenix, Az

Unread post02 Nov 2017, 20:19

usnvo wrote: 2 MT-30s can provide all the power required for EMALS, the rest of the ship, and then some without even working hard.

Saving power for laser CWIS and railguns. :P
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
Offline

wolfpak

Enthusiast

Enthusiast

  • Posts: 67
  • Joined: 12 Jan 2014, 19:26

Unread post03 Nov 2017, 00:09

The use of DC is probably because they don't have the technology to make AC work. It's a step back in my opinion. The auto industry abandoned DC for similar applications long ago because of the problems and expense of maintaining those systems.

From published reports the reactors on the Fords put out around 770MW compare to 525 or so on the Nimitz class. They're comparable to those in domestic power plants that are rated at 800MW. They may be smaller in size
Offline
User avatar

neptune

Elite 2K

Elite 2K

  • Posts: 2524
  • Joined: 24 Oct 2008, 00:03
  • Location: Houston

Unread post03 Nov 2017, 03:08

spazsinbad wrote:.... to the energy storage device,” he said. Wang added that in the future, the same technology could be used to launch not just aircraft, but also missiles and satellites, and maybe even power high-speed trains.....


....nice idea "IF", I'll wait-to-see when the new trains are competing in the commercial market; until then, the Ford is underway!
:)
Offline
User avatar

spazsinbad

Elite 3K

Elite 3K

  • Posts: 19235
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post10 Nov 2017, 04:16

One wonders how some defence 'reporters' are employed. Apparently having no recent knowledge about topic is OKay. OK?
China claims breakthrough in electromagnetic launch system for aircraft carrier
09 Nov 2017 Mike Yeo

"MELBOURNE, Australia — China has reportedly achieved a breakthrough on a conventional propulsion system for its next carrier, which would allow it to operate advanced catapults for launching aircraft without necessitating the use of nuclear propulsion....

...The People’s Liberation Army Navy, or PLAN, has been operating a pair of catapults at its carrier training base at Huangdicun since the second half of 2016. The pair are believed to consist of a single steam catapult and one EMALS. The service is evaluating both systems and carrying out test launches using a modified Shenyang J-15 (Flying Shark) carrierborne fighter jet....

...The new power-generating system could allow PLAN warships to be armed with modern weapons like electromagnetic rail guns and directed-energy weapons. In March, Ma had told state broadcaster CCTV that the “ultimate aim” of his work on the integrated propulsion system was to “solve the problem of deploying high-energy weapons” from its ships.

He has also subsequently claimed that China’s EMALS technology was more advanced and more reliable than the system used on the U.S. Navy’s aircraft carrier Gerald R. Ford. The Ford marked its first aircraft launches using EMALS during post-commissioning trials in July.

Its development in the U.S. Navy has, however, been beset with problems, particularly concerning reliability while testing modifications of EMALS, which are meant to allow it to launch the Boeing F/A-18E/F Super Hornet and EA-18G Growler while carrying external fuel tanks. [fixed OK-new tech does have problems-but Chinese new tech does not have?]

Source: https://www.defensenews.com/naval/2017/ ... ch-system/
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline
User avatar

neptune

Elite 2K

Elite 2K

  • Posts: 2524
  • Joined: 24 Oct 2008, 00:03
  • Location: Houston

Unread post10 Nov 2017, 23:09

spazsinbad wrote:... operate advanced catapults for launching aircraft without necessitating the use of nuclear propulsion....... “solve the problem of deploying high-energy weapons” ...


....I am looking forward to the public demonstration of the advanced train propulsion system, as associated with this technological breakthru!!
:wink:
Offline
User avatar

spazsinbad

Elite 3K

Elite 3K

  • Posts: 19235
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post11 Nov 2017, 15:45

Raytheon's JPALS Brings Precision Landing
11 Nov 2017 Angus Batey

"What appears to be this counter-intuitive proposition is being made by Raytheon, whose JPALS (Joint Precision Approach and Landing System) is in development for the U.S. Navy, who will use it to help F-35 pilots land on carrier decks. The system, which uses GPS data to provide pilots with a landing spot measured in centimetres, will also be part of the landing technology utilized by the MQ-25 unmanned tanker program, regardless of which aircraft is selected.

Raytheon's contract with the U.S. Navy was let in 2008: the carrier-borne iteration of JPALS is currently in test, and is scheduled to achieve initial operating capability in 2019. Clues to the system's utility on land go back to the roots of the program in the 1990s, when the U.S. Department of Defense published a precision-landing requirement. In 1996, following the deaths of all 34 people on board a USAF Boeing T-43A which crashed on a non-precision approach to Dubrovnik, efforts intensified to field a system that offered that capability in a deployable form....

...So far, the system has been flown on F-35 and F-18 aircraft, but it can be retrofitted to any platform. The hardware is mainly contained in the ship- or ground-based package, which Ray describes as "Humvee-sized": some modification may be required to the aircraft, but usually only to software of equipment already carried on board.

"The JPALS unit can talk to whatever aircraft can receive its waveform," says Raytheon consultant and F-18 pilot Brooks Cleveland. "They need GPS, which almost every airplane these days has; they need an inertial navigation system, which, again, most have; they need some spare processing power, typically found in the mission computer; and then the key piece is a radio that can recognise the JPALS waveform. That's not a new radio: it'll mean a software upgrade, or perhaps a chip in an existing radio."

The need for a new waveform has been driven by security requirements. The links between the JPALS unit and the aircraft are encrypted, and designed to have a low probability of being observed or intercepted by a third party. Unlike the hemispherical radio frequency "bubble" produced by a radar-based system, Cleveland says JPALS' RF footprint is "virtually non-existent." To further minimize any chance of detection in a deployed ground operation, the unit can be placed up to 20 miles away from the desired landing site.

JPALS is capable of guiding up to 50 inbound aircraft simultaneously, from ranges of up to 200 miles....

...The system's reliance on GPS may leave it susceptible to jamming - not of the links between the unit and the aircraft, but of the signals from the GPS satellite constellation. The U.S. DoD has recognized GPS resilience as a potential area of vulnerability, and as part of its mitigations it has contracted with Raytheon for the delivery of a next-generation GPS ground station.

"Our customers will tell you that that's one of the hardest problems we've had to tackle across the DoD," says Ray. "I think the architecture that we're delivering as part of the upgraded GPS will be able to meet those needs and provide more resilience against those low-end jam threats. And because JPALS is going to be accessing the GPS system, as GPS moves to the next-generation system it will make JPALS much more resilient.""

Source: http://aviationweek.com/dubai-air-show- ... on-landing
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Previous

Return to General F-35 Forum

Who is online

Users browsing this forum: mtoner and 11 guests