CV-18 Fujian/003 CATOBAR carrier thread

[antiterror13]

If you look at the difference between EMALS and steam catapults, the EMALS is a much simpler design with far less complexity.

Is the same (kind of) analogy of vacuum tube and transistor ? or CRT vs LCD ?

 

[snake65]

Not exactly. Mechanical equipment is much simpler indeed, but the electric part is quite complex.

 

[AndrewS]

Is the same (kind of) analogy of vacuum tube and transistor ? or CRT vs LCD ?

A better analogy is an Electric Vehicle Drivetrain versus Petrol Engine Drivetrain

1. EV Drivetrain = Typically 20 parts from the Battery + Power cable + Electric Motor
2. Petrol Drivetrain = Typically 200 parts in the engine + [x] transmission components

Remember that complexity scales exponentially, and is not a linear function.

And lastly, remember a steam catapult relies on piping superheated steam across much of an aircraft carrier. An electricity cable looks easy by comparison.

 

[PeoplesPoster]

A better analogy is an Electric Vehicle Drivetrain versus Petrol Engine Drivetrain

1. EV Drivetrain = Typically 20 parts from the Battery + Power cable + Electric Motor
2. Petrol Drivetrain = Typically 200 parts in the engine + [x] transmission components

Remember that complexity scales exponentially, and is not a linear function.

And lastly, remember a steam catapult relies on piping superheated steam across much of an aircraft carrier. An electricity cable looks easy by comparison.

going by this same analogy, a petrol drive train can be fixed by a backyard mechanic almost anywhere with the right parts wherease a EV drive train, your gonna have to take it back to the dealer.

 

[AndrewS]

going by this same analogy, a petrol drive train can be fixed by a backyard mechanic almost anywhere with the right parts wherease a EV drive train, your gonna have to take it back to the dealer.

Not really.

The latest EV Drivetrains are almost 100% reliable and don't even need to be serviced.
You have Teslas which have done 500,000 miles for example under these conditions.

In comparison, a petrol drivetrain would have need to be serviced at least 20 times, and have almost certainly broken down many times over the same period. Plus a backyard mechanic can't service the latest petrol drivetrains because all the components are controlled by electronics and need a dealer to plug into.

There's a reason why both the Chinese Navy and US Navy are going with EMALS. It's just that the US Navy really screwed up their first design implementation on the Ford, but the next carrier should fix these design mistakes.

 

[kwaigonegin]

Not really.

The latest EV Drivetrains are almost 100% reliable and don't even need to be serviced.
You have Teslas which have done 500,000 miles for example under these conditions.

In comparison, a petrol drivetrain would have need to be serviced at least 20 times, and have almost certainly broken down many times over the same period. Plus a backyard mechanic can't service the latest petrol drivetrains because all the components are controlled by electronics and need a dealer to plug into.

There's a reason why both the Chinese Navy and US Navy are going with EMALS. It's just that the US Navy really screwed up their first design implementation on the Ford, but the next carrier should fix these design mistakes.

Right. EMALS should have significantly less moving parts an any good engineering practitioner will tell you that less less moving parts there is the better it is for reliability and maintenance going forward once they iron out the teething problems.

 

[taxiya]

going by this same analogy, a petrol drive train can be fixed by a backyard mechanic almost anywhere with the right parts wherease a EV drive train, your gonna have to take it back to the dealer.

For old full mechnical petro car engine a "backyeard mechanic" can do the job, but the Navy will always use technicians who are properly trained and certified by the manufacturer (eg. the official dealer shop). So the "backyard" thing isn't relevant regarding maintenance of catapult.

Less moving parts means higher reliability, less chances of breaking down etc, so you have less need of repair to begin with. Most electronics do not wear and will last almost indefinitely so long as it is kept within its operational specification, however a perfectly qualified mechanical part wears naturally and will fail at an unknown time point. If you look at a computer, the first thing breaks are likely battery (chemicals degradation), harddisks (mechanical wearing), fan (mechanical wearing) and monitor (chemical degradation). You will never get the chance to see CPU, RAM and SSD failure before you buy a new computer.

 

[latenlazy]

going by this same analogy, a petrol drive train can be fixed by a backyard mechanic almost anywhere with the right parts wherease a EV drive train, your gonna have to take it back to the dealer.

For old full mechnical petro car engine a "backyeard mechanic" can do the job, but the Navy will always use technicians who are properly trained and certified by the manufacturer (eg. the official dealer shop). So the "backyard" thing isn't relevant regarding maintenance of catapult.

Less moving parts means higher reliability, less chances of breaking down etc, so you have less need of repair to begin with. Most electronics do not wear and will last almost indefinitely so long as it is kept within its operational specification, however a perfectly qualified mechanical part wears naturally and will fail at an unknown time point. If you look at a computer, the first thing breaks are likely battery (chemicals degradation), harddisks (mechanical wearing), fan (mechanical wearing) and monitor (chemical degradation). You will never get the chance to see CPU, RAM and SSD failure before you buy a new computer.

The whole analogy is faulty. In both an ICE drive train and an EV you’re just swapping out parts, whether that’s a mechanical or electrical connector. If the electrical connectors are directly soldered and can’t be replaced via unplugging or replugging cables that’s not an issue inherent to electrical systems but an issue specific to how the electrical component was deliberately designed. And this is no different from a mechanical component which isn’t designed to be disassembled, which ICE cars can also have. Serviceability in general is not a matter of your system is electrical or mechanical but whether you designed a component to be easily serviceable.

 

[davidau]

Not really.

The latest EV Drivetrains are almost 100% reliable and don't even need to be serviced.
You have Teslas which have done 500,000 miles for example under these conditions.

In comparison, a petrol drivetrain would have need to be serviced at least 20 times, and have almost certainly broken down many times over the same period. Plus a backyard mechanic can't service the latest petrol drivetrains because all the components are controlled by electronics and need a dealer to plug into.

There's a reason why both the Chinese Navy and US Navy are going with EMALS. It's just that the US Navy really screwed up their first design implementation on the Ford, but the next carrier should fix these design mistakes.

Probally will copy China's DC configuration!

 

[ACuriousPLAFan]

According to @还是捣蛋 on Weibo, the upper level of the bridge on CV-18 Fujian has got a couple new windows on the starboard side.

This photograph is photoshopped, but the changes are real.


Here's how the bridge looked like before the changes (actual, unedited):


Here's a CGI illustration on the changes, made by @大包CG on Weibo.