![]() |
|
|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
![]()
"Greg D. Moore \(Strider\)" wrote:
Of course it doesn't work that way in practice. Person 1 looks and says, "hmm, looks good, besides, if I'm wrong, #2 will catch it." Person 2 looks and says, "well I'm in a hurry, I'm sure #1 caught anything, besides, that's why #3 is there." Person 3 looks and says, "well, I don't want to be the guy that calls out #1 and #2 for being wrong, so I won't say anything. I'm sure if this was really a problem, they'd have caught it." Adding people like this does not necessarily make things any safer and in fact can make things less safe. What's the cause and effect here? Having too many people, or poor implementation/allocation of responsibility, or poor training and supervision? The way to properly due this is to focus on failsafe procedures. For one, an interlock that doesn't permit the clock to go past X time unless the door is registered as closed (and I'd be surprised if they don't have this). On submarines we have a switch that operates a remote display in the control room indicating whether or not a hatch is shut - but when shutting the hatch we still had people verify the hatch shut and locked. The indicator was used to verify that conditions had not changed, but eyeballs and hands (two pairs of each) were used to establish that condition. The people are mostly a feel-good measure. And insurance against instrumentation failure. Nine time out of ten the switch on the hatch I was usually associated with shutting after a period inport was non functional because it had been bumped or damaged as the hatch in question was the main access and loading path into and out of the submarine. And even after the care taken while shutting the hatch, and the care taken to verify its condition on shutting - when we went deep we regularly (as in every five minutes or so) verfied the hatch remained shut and not leaking for the entire time we were deep. When our asses were on the line, if possible we didn't trust instrumention, and if *required* to trust instrumentation we had two completely seperate instruments wherever possible/practical. We had three different instruments for measuring depth - two on seperate power circuits, and the third was mechanical. Think about when you fly. The flight attendants are told to check the doors. They don't have all 3 or 5 or whatever check every door. And for the main loading door, they have a procedure to make sure the door is locked and the slide enabled. When's the last time you heard of a door on an airliner not being sealed properly? I suspect that if on takeoff an airliner was committed irrevocably to a course where minor door failure was extremely dangerous, even if an abort was laid on, and the door absolutely had to perform for as much as two weeks... They just _might_ treat them differently. That they have had decades of experience and millions of operational cycles might also have something to do with it. D. -- Touch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL |
#12
|
|||
|
|||
![]()
Jorge R. Frank wrote:
And there you have it. Are additional inspectors useful or are they not? Are there more people in the white room post CAIB than before ? If not, then isn't it just a case of using the poeple who are already there to tripple check everything ? |
#13
|
|||
|
|||
![]()
airliners routinely go back to airport if they dont pressurize
properly, plus most doors are fail safe, pressure makes them tighter. this info from national geographics air emergency show, excellent show ion how stuff goes wrong......... |
#14
|
|||
|
|||
![]()
Anything our NASA can do, India can do at 10% the cost, as well as
within a fourth the time, and China could cut each of those in half. ~ BG Alan Erskine wrote: No wonder the Shuttle is so pharking expensive to operate! Any news on the nitty-gritty of the Orion hatch; number of people needed for closure? |
#15
|
|||
|
|||
![]()
On Mar 17, 3:40�pm, BradGuth wrote:
Anything our NASA can do, India can do at 10% the cost, as well as within a fourth the time, and China could cut each of those in half. �~ BG Alan Erskine wrote: No wonder the Shuttle is so pharking expensive to operate! Any news on the nitty-gritty of the Orion hatch; number of people needed for closure?- Hide quoted text - - Show quoted text - new indian car coming to US 4 grand. new chinese car 8 grand with 100,000 mile warranty. they just needed dealer network, GM is supplying that by shedding 2/3 of its dealers nationwide |
#16
|
|||
|
|||
![]()
"Derek Lyons" wrote in message
... "Greg D. Moore \(Strider\)" wrote: Of course it doesn't work that way in practice. Person 1 looks and says, "hmm, looks good, besides, if I'm wrong, #2 will catch it." Person 2 looks and says, "well I'm in a hurry, I'm sure #1 caught anything, besides, that's why #3 is there." Person 3 looks and says, "well, I don't want to be the guy that calls out #1 and #2 for being wrong, so I won't say anything. I'm sure if this was really a problem, they'd have caught it." Adding people like this does not necessarily make things any safer and in fact can make things less safe. What's the cause and effect here? Having too many people, or poor implementation/allocation of responsibility, or poor training and supervision? I'll be honest here, these types of issues have been of interest to me, but I don't really keep track of wher I've read stuff. My simple recollection is it's just a matter of human nature and people not taking responsibility. i.e. not really a matter of training so much. The way to properly due this is to focus on failsafe procedures. For one, an interlock that doesn't permit the clock to go past X time unless the door is registered as closed (and I'd be surprised if they don't have this). On submarines we have a switch that operates a remote display in the control room indicating whether or not a hatch is shut - but when shutting the hatch we still had people verify the hatch shut and locked. The indicator was used to verify that conditions had not changed, but eyeballs and hands (two pairs of each) were used to establish that condition. Which is sort of what I was getting at without being real clear. Note you mention 2 people, which seem to be about the right number. And note I'm not arguing against the Mark I eyeball checking important things like the hatch being open or closed. Merely that adding more people doesn't necessarily help and ideally they are confirming what the system is already telling you. Think about when you fly. The flight attendants are told to check the doors. They don't have all 3 or 5 or whatever check every door. And for the main loading door, they have a procedure to make sure the door is locked and the slide enabled. When's the last time you heard of a door on an airliner not being sealed properly? I suspect that if on takeoff an airliner was committed irrevocably to a course where minor door failure was extremely dangerous, even if an abort was laid on, and the door absolutely had to perform for as much as two weeks... They just _might_ treat them differently. Might, but probably not too much. That they have had decades of experience and millions of operational cycles might also have something to do with it. That is probably by far the bigger factor. -- Greg Moore Ask me about lily, an RPI based CMC. |
#17
|
|||
|
|||
![]()
On Mar 20, 9:57�pm, "Greg D. Moore \(Strider\)"
wrote: "Derek Lyons" wrote in message ... "Greg D. Moore \(Strider\)" wrote: Of course it doesn't work that way in practice. Person 1 looks and says, "hmm, looks good, besides, if I'm wrong, #2 will catch it." Person 2 looks and says, "well I'm in a hurry, I'm sure #1 caught anything, besides, that's why #3 is there." Person 3 looks and says, "well, I don't want to be the guy that calls out #1 and #2 for being wrong, so I won't say anything. �I'm sure if this was really a problem, they'd have caught it." Adding people like this does not necessarily make things any safer and in fact can make things less safe. What's the cause and effect here? �Having too many people, or poor implementation/allocation of responsibility, or poor training and supervision? I'll be honest here, these types of issues have been of interest to me, but I don't really keep track of wher I've read stuff. My simple recollection is it's just a matter of human nature and people not taking responsibility. �i.e. not really a matter of training so much. The way to properly due this is to focus on failsafe procedures. �For one, an interlock that doesn't permit the clock to go past X time unless the door is registered as closed (and I'd be surprised if they don't have this). On submarines we have a switch that operates a remote display in the control room indicating whether or not a hatch is shut - but when shutting the hatch we still had people verify the hatch shut and locked. �The indicator was used to verify that conditions had not changed, but eyeballs and hands (two pairs of each) were used to establish that condition. Which is sort of what I was getting at without being real clear. �Note you mention 2 people, which seem to be about the right number. And note I'm not arguing against the Mark I eyeball checking important things like the hatch being open or closed. �Merely that adding more people doesn't necessarily help and ideally they are confirming what the system is already telling you. Think about when you fly. The flight attendants are told to check the doors. They don't have all 3 or 5 or whatever check every door. �And for the main loading door, they have a procedure to make sure the door is locked and the slide enabled. When's the last time you heard of a door on an airliner not being sealed properly? I suspect that if on takeoff an airliner was committed irrevocably to a course where minor door failure was extremely dangerous, even if an abort was laid on, and the door absolutely had to perform for as much as two weeks... �They just _might_ treat them differently. Might, but probably not too much. That they have had decades of experience and millions of operational cycles might also have something to do with it. That is probably by far the bigger factor. -- Greg Moore Ask me about lily, an RPI based CMC.- Hide quoted text - - Show quoted text - commercial airliners have crashed because of doors not sealed properly, killing all on board and sometimesa just select passengers when outward opening cargo doors come open in flight. |
|
Thread Tools | |
Display Modes | |
|
|