"Simon Robbins" wrote in message ...
"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.

Si

Thanks for the info. So none of the flight controls interface with
the 1553 at all? I'm just now getting familiar with Mil-HDBK-516
(airworthiness criteria) for my new job and not sure if some of the
equipment we are installing on the 1553 bus would affect/cause latency
for flight control. From what you've said, apparently that's a
non-issue then...

I guess on a non-related note, how exactly does equipment on the 1553
bus manage communications to prevent them from overlapping / "stepping
on" each other? Is there something in the data sentence once a unit
begins transmitting that puts all other equipment on "hold" until it
is done sending data? Wouldn't there be interrupts needed for
critical equipment to override less critical sentences?

Thanks again!
Dave