Pyrotechnic Mishaps ...

didn't the Mars Observer Transfer stage have a pyro anomaly
on separation?
when they kicked it out of the shuttle it tossed shrapnel around?

r

In article . com,
pat wrote:
didn't the Mars Observer Transfer stage have a pyro anomaly
on separation?
when they kicked it out of the shuttle it tossed shrapnel around?

No, that was ACTS's TOS stage. (MO went up on a Titan, although it did
use a TOS as the final stage.) The separation command was supposed to fire
both (redundant) detonators attached to one of two (redundant) pyro
systems; instead it fired one detonator on each pyro system, and the
doubled energy threw fragments around. Design error in the wiring
harness, hidden by poorly organized documentation that made the mistake
hard to spot even when the investigators knew what to look for. Testing
verified implementation of the design rather than conformance to specs.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Henry Spencer wrote:

The separation command was supposed to fire
both (redundant) detonators attached to one of two (redundant) pyro
systems; instead it fired one detonator on each pyro system, and the
doubled energy threw fragments around.



That's freakishly close to what happened on Soyuz 11- except in that
case it was the back-up pyro system that fired the primary also, IIRC.

Pat

(Henry Spencer) wrote:

No, that was ACTS's TOS stage. (MO went up on a Titan, although it did
use a TOS as the final stage.) The separation command was supposed to fire
both (redundant) detonators attached to one of two (redundant) pyro
systems; instead it fired one detonator on each pyro system, and the
doubled energy threw fragments around.

Including at least one that pentrated the shuttle's aft bulkhead.

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

In article ,
Derek Lyons wrote:
...instead it fired one detonator on each pyro system, and the
doubled energy threw fragments around.

Including at least one that pentrated the shuttle's aft bulkhead.

Indeed so. No serious harm done, as it happened... but the margins were
thin that day. This was quite properly treated as a worrisome problem,
not written off on the grounds that it didn't actually break anything.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |