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John C
April 27th 06, 06:35 PM
Is the next generation of carriers going to launch planes differently? ie
Mag Lev technology?
When is it due out and is it still considered expirmental?

grassStain
April 27th 06, 07:04 PM
"John C" > wrote in message
...
> Is the next generation of carriers going to launch planes differently? ie
> Mag Lev technology?
> When is it due out and is it still considered expirmental?

There's currently nothing in the works to replace the current steam
catapults (at least in the near future).

FatKat
April 27th 06, 07:59 PM
What would the benefits of MagLev be?

John Dallman
April 27th 06, 08:54 PM
In article om>,
(FatKat) wrote:

> What would the benefits of MagLev be?

Well, adding a whole of of weight to the plane to start with, in either
permanent magnets or electromagnets so that you could get enough repulsion
to lift the plane off the deck. You'd then have three basic strategies:

- Build said magnets into the plane, reducing its performance.
- Put them on some kind of plane carrier, which you discard overboard
like a catapult bridle. Since it weighs around the same amount as
the plane, this will be quite expensive.
- Use a plane carrier but don't discard it. Stopping it will be about
as difficult as arresting a fully-loaded plane, which is going to
push up the size of the carrier in some way or other.

The obvious "advantage" of the first is that it enables you to do without
a conventional undercarriage on the plane, thus saving some weight, and
meaning that you can only land on a correctly equipped carrier or
airfield. All you can do anywhere else is try to crash gently.

Overall, maglev for launching aircraft looks like an even more expensive
version of the "Flexible Deck" silly idea that the Royal Navy played with
in the 1950s.

On the other hand, replacing a steam catapult with a linear accelerator,
that pulls an aircraft along on convention wheels is much less silly.
That's ben discussed, vaguely, for the forthcoming cancellation of the
Royal Navy's CVF. That ship concept doesn't feature a steam plant,
replacing it with gas turbines driving electric generators, plus electric
motors turning the propellers. With that, using the electric plant to
catapult aircraft make sense. However, if they get built, the plan is to
carry STOVL JSF, and use a ski-jump rather than catapults. So the idea
hasn't been studied in much detail, to the best of my knowledge.

---
John Dallman, , HTML mail is treated as probable spam.

Guy Alcala
April 27th 06, 09:09 PM
FatKat wrote:

> What would the benefits of MagLev be?

Well, electromagnetic anyway. Smoother
accel, no steam needed, works much better
with Integrated-electric propulsion (or
whatever the currently in vogue term is),
lighter, less maintenance, modular etc.
See:

http://www.globalsecurity.org/military/systems/ship/systems/emals.htm

Guy

DDAY
April 27th 06, 11:19 PM
----------
In article <TI74g.23$nk4.18@trnddc03>, "grassStain" >
wrote:

> There's currently nothing in the works to replace the current steam
> catapults (at least in the near future).

Are you sure? I was recently at the SeaAirSpace conference and picked up
some literature on current research as well as the next CVN and I found
several references to electromagnetic catapult systems. I'll look for the
stuff I got, but my memory is that this is indeed planned for the next
carrier.




D

grassStain
April 27th 06, 11:22 PM
"DDAY" > wrote in message
ink.net...
> ----------
> In article <TI74g.23$nk4.18@trnddc03>, "grassStain" >
> wrote:
>
> > There's currently nothing in the works to replace the current steam
> > catapults (at least in the near future).
>
> Are you sure?

No

Thomas Schoene
April 27th 06, 11:34 PM
grassStain wrote:
> "John C" > wrote in message
> ...
>
>>Is the next generation of carriers going to launch planes differently? ie
>>Mag Lev technology?
>>When is it due out and is it still considered expirmental?
>
>
> There's currently nothing in the works to replace the current steam
> catapults (at least in the near future).

Wrong. There are both electromagnetic catapults (EMALS) and
turboelectric arresting gear in development.

http://www.ga.com/atg/emals.php
http://www.ga.com/atg/arrestgear.php

I talked to folks from GA earlier this year who said that these are both
on track for inclusion in CVN-78, which is supposed to begin
construction next year.

--
Tom Schoene
To email me, replace "invalid" with "net"

Thomas Schoene
April 27th 06, 11:36 PM
John Dallman wrote:
[snip]
> On the other hand, replacing a steam catapult with a linear accelerator,
> that pulls an aircraft along on convention wheels is much less silly.
> That's ben discussed, vaguely, for the forthcoming cancellation of the
> Royal Navy's CVF. That ship concept doesn't feature a steam plant,
> replacing it with gas turbines driving electric generators, plus electric
> motors turning the propellers. With that, using the electric plant to
> catapult aircraft make sense. However, if they get built, the plan is to
> carry STOVL JSF, and use a ski-jump rather than catapults. So the idea
> hasn't been studied in much detail, to the best of my knowledge.

They've already build working models and the system is going into new
USN carriers in the next few years.

--
Tom Schoene
To email me, replace "invalid" with "net"

John Dallman
April 28th 06, 10:19 PM
In article et>,
(Thomas Schoene) wrote:

> John Dallman wrote:
> [snip]
> > On the other hand, replacing a steam catapult with a linear
> > accelerator, that pulls an aircraft along on convention wheels is
> > much less silly.
> They've already built working models and the system is going into new
> USN carriers in the next few years.

Coo. Are they going to electric propulsion too?

---
John Dallman, , HTML mail is treated as probable spam.

Thomas Schoene
April 29th 06, 02:23 AM
John Dallman wrote:
> In article et>,
> (Thomas Schoene) wrote:
>
>
>>John Dallman wrote:
>>[snip]
>>
>>>On the other hand, replacing a steam catapult with a linear
>>>accelerator, that pulls an aircraft along on convention wheels is
>>>much less silly.
>>
>>They've already built working models and the system is going into new
>>USN carriers in the next few years.
>
>
> Coo. Are they going to electric propulsion too?

Not yet.
--
Tom Schoene
To email me, replace "invalid" with "net"

The Raven
April 29th 06, 04:44 AM
"John C" > wrote in message
...
> Is the next generation of carriers going to launch planes differently? ie
> Mag Lev technology?
> When is it due out and is it still considered expirmental?

Mag Lev would probably cause all sorts of electrical/electronic issues in
the aircraft.

--
The Raven
http://www.80scartoons.co.uk/batfinkquote.mp3
** Now I will bring chaos to the world!

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