On Fri, 11 Jun 2004 14:06:45 -0700, (Harry
Andreas) wrote:

In article , "Simon Robbins"
wrote:

"David Harper" wrote in message
om...
Does the C-130 have two 1553 buses onboard? One for flight control
and one for EW/mission systems?

I don't think 1553 is used for flight control since the latency and speed
isn't sufficient. Mission systems may well use it though. I think by nature
1553 is dual-redundant so that's where you might get the idea of two from.
Not familiar with the C-130 personally though.

1553 has no inherent connection with dual-redundancy.
In fact, 1553 is usually used as a single bus.

Yep - the spec allows for x-redundancy. Although you'd want to keep a
lid on the amount of redundancy :

More redundancy = more resilience
More redundancy = more bits = more cost.

After a while, the law of diminishing returns comes in, making it daft
to have too many redundant legs. Dual would make a big improvement in
resilience, Triple would be a partial improvement over dual but after
triple, you're probably getting into gold-plating levels. It also
depends on how much space there is. If you do your dual redundance
with the cables in the same runs, you're only effectively getting
single redundancy cos a cut in one place will cut both cables.

Pete Lilleyman

(please get rid of ".getrid" to reply direct)
(don't get rid of the dontspam though ;-)