I know better then the pilots.. now I'm suing!

jtrain609 said:
What did they do that required an entry in the logbook? You've never had a mechanic come out to take a look at something that may be "a little fishy" and had them say, "Oh yeah, they do that sometimes, but we can't recall the fault so don't worry about it; just gremlins."

I've had that happen, and had it just be gremlins that never popped back up again.

EDIT: Or...you deleted your post?
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I did. I misread the report. I thought I understood it to say that they were unable to clear the messages and the mechanic had to do it for them. Obviously not the case, however.
 
jtrain609 said:
Further, it looks like they were on top of the situation the whole time, talking with MX control twice and following the QRH when things started going south. All in all it sounds like they were handed a constantly crumbling crap sandwich and make a series of decisions that, at the time, seemed like good choices, without realizing it was all about to drop out from under them in short order.
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From reading the NTSB recommendations, it sounds like the QRH wasn't very clear--stating that 30 mins of battery power remained, but with no direction to land at the nearest suitable airport.

jtrain609 said:
What did they do that required an entry in the logbook? You've never had a mechanic come out to take a look at something that may be "a little fishy" and had them say, "Oh yeah, they do that sometimes, but we can't recall the fault so don't worry about it; just gremlins."

I've had that happen, and had it just be gremlins that never popped back up again.
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NTSB said:
He noticed five status messages displayed on the lower engine indicating and crew alert system (EICAS) screen; however, he could not recall what the messages were. He then called maintenance to report the messages. A mechanic came into the cockpit, cleared the messages, and stated that they were “good to go.” No logbook entries were made regarding this event.
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The FAA wants *every* discrepancy written up, including status messages that are cleared via reset procedure. They are being extremely strict on this...I wouldn't be surprised if it had something to do with this incident. Not blaming the pilots at all, but I would bet that if something similar happened today they would be looking at certificate action.
 
There is a situation that can develop in the CRJ involving the closing of DC ties. There are two auto ones and and manual. If both auto ties have closed (you are having a REALLY bad day at this point) and then something else happens that causes you to run a QRH that directs the closing of the manual DC tie, you end up painting yourself into a corner that you probably aren't going to come out of. Despite that, until our most recent revision of the QRH there was nothing in there about maybe NOT closing the manual tie if both auto ties have already shut.

Point being, stuff like this happens but when it does, it tends to happen fast. The NTSB report seems to read that it was a slow cascade if system faults and they really didn't know what they wouldn't have (in this case reversers, spoilers, brakes and a way to shut off the engines.
 
BobDDuck said:
There is a situation that can develop in the CRJ involving the closing of DC ties. There are two auto ones and and manual. If both auto ties have closed (you are having a REALLY bad day at this point) and then something else happens that causes you to run a QRH that directs the closing of the manual DC tie, you end up painting yourself into a corner that you probably aren't going to come out of. Despite that, until our most recent revision of the QRH there was nothing in there about maybe NOT closing the manual tie if both auto ties have already shut.
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I haven't been through an initial yet that didn't involve me scribbling notes in the QRH to remind me to think twice before blindly following an abnormal or emergency checklist. Seems that most operators don't want the liability of directing you to think outside the box.
 
jtrain609 said:
Indeed, it took 2.5 hours to go from "battery power" to having no juice left in the batteries, when it should only take 30 minutes to deplete the batteries.
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They weren't running on battery only for that long, but only partial battery power was being used.
 
PGT said:
They weren't running on battery only for that long, but only partial battery power was being used.
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Also.....all these "battery will last for XX minutes on batt only" type things; it's wise to half that time given....or otherwise pad it in some way, as the time given is usually for a brand-new battery. I wouldn't take the 30/40/60/etc minutes the "battery will last" as any kind of gospel or number to hang your hat on.
 
The thing is, there's so much redundancy with the 757/767 electrical system that makes something like this pretty improbable. From my understanding (and keep in mind, I'm still in school on the thing), the left and right main AC and DC buses (which power just about everything important) are normally powered independently via the respective engine generator. In flight, the left and right systems operate completely independently of one another; only a failure of one of the main power sources (an IDG...the engine generator) would cause the bus ties to close and combine the two sides of the system together.

With the main AC and DC systems powered by the IDGs, the main battery doesn't really do much. The battery bus and standby buses (buses that power the "oh crap we lost both engines" stuff) are powered by the main buses. I think (maybe one of the guys above can confirm this) that you should be able to deselect the main battery switch in flight and nothing will happen. The only thing that's going to run down the main battery in-flight is if you lose main AC and DC sources (both engines fail and you don't have your APU up yet) or you physically move the standby bus switch out of the AUTO position.

So, after reading the NTSB report, I'm scratching my head. Someone must have left an arc welder somewhere in the system. ;)

P.S.: Cool this thread popped up when it did. Thinking about how the system works and writing it out actually helps me study and visualize it better!
 
Choosing 22R was done to enable the lottery processors (attorneys) more wiggle room. This lady found a lottery ticket, and wants the payday.

She'll get one too, more than likely.
 
I know there was a reason they used 22R, can't remember exactly why.

I found a rough draft of my presentation, can't find the paper associated with it, here is a slide:

clipboard01ew.jpg
 
"The only thing that's going to run down the main battery in-flight is if you lose main AC and DC sources (both engines fail and you don't have your APU up yet) or you physically move the standby bus switch out of the AUTO position."

Following the checklist for standby power off, they moved the standby power selector to battery, which disconnects the battery charger from the system, even if it's powered. Then, the "battery discharge" light on the overhead panel comes on. This should have been their clue they needed to land within 30 minutes. That the battery powered the standby AC/DC, battery, and hot battery buss for 2.5 hours is remarkable. Perhaps there is more to the story about why that happened that I'm missing. But, in the end, the AA 757 battery failed and that's why they started losing systems on the standby buses, which is where the important stuff usually is. They lost trim capability which resulted in pitch control difficulty and probably the decision for the flaps 20 landing (faster speed so jet is less out of trim). I'm thinking blown tires on landing because of no antiskid. Then, the engines wouldn't shut down with the fuel control switches or fire handles (no power).

At that point I'd be running like hell away from this possessed airplane that won't do what I'm telling it. Check please.....
 
DE727UPS said:
"The only thing that's going to run down the main battery in-flight is if you lose main AC and DC sources (both engines fail and you don't have your APU up yet) or you physically move the standby bus switch out of the AUTO position."

Following the checklist for standby power off, they moved the standby power selector to battery, which disconnects the battery charger from the system, even if it's powered. Then, the "battery discharge" light on the overhead panel comes on. This should have been their clue they needed to land within 30 minutes. That the battery powered the standby AC/DC, battery, and hot battery buss for 2.5 hours is remarkable. Perhaps there is more to the story about why that happened that I'm missing. But, in the end, the AA 757 battery failed and that's why they started losing systems on the standby buses, which is where the important stuff usually is. They lost trim capability which resulted in pitch control difficulty and probably the decision for the flaps 20 landing (faster speed so jet is less out of trim). I'm thinking blown tires on landing because of no antiskid. Then, the engines wouldn't shut down with the fuel control switches or fire handles (no power).

At that point I'd be running like hell away from this possessed airplane that won't do what I'm telling it. Check please.....
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Good times, good times. That makes sense. I got a chance to sit down and read this over a bit more now that class is out for the day, and I see that it was a failure of a relay that caused this. Not much you can do about that.

I wonder if AA's 757s are ETOPS certified. At my company, the 757's APU battery is paralleled with the main battery to provide power for the AC and DC standby buses. That increases standby power on batteries from 30 to 90 minutes. I'm not sure if that's the normal configuration for non-ETOPS birds as well, or if our batteries are simply beefed up to maintain the 180 ETOPS certification.
 
dasleben said:
I wonder if AA's 757s are ETOPS certified. At my company, the 757's APU battery is paralleled with the main battery to provide power for the AC and DC standby buses. That increases standby power on batteries from 30 to 90 minutes. I'm not sure if that's the normal configuration for non-ETOPS birds as well, or if our batteries are simply beefed up to maintain the 180 ETOPS certification.
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Huh, that's quite different than Delta. Our ETOPS 757's are just like our 767ERs in that they have an HDG (hydraulic driven generator) so no need to up the battery time. The domestic jets only have thirty minutes.

However, I just switched to the Maddog so I have mostly brain dumped the 757. I could be lying about everything above.
 
JoelT said:
Huh, that's quite different than Delta. Our ETOPS 757's are just like our 767ERs in that they have an HDG (hydraulic driven generator) so no need to up the battery time. The domestic jets only have thirty minutes.

However, I just switched to the Maddog so I have mostly brain dumped the 757. I could be lying about everything above.
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Yeah, our 757-200s and 767-300ERs have the 90 minute standby systems and the HDGs (dunno why both). I think one of the 767s may only have the 30 minute batteries, but I'm not sure on that. Either way, if you're depending on the 30 or 90 minute batteries instead of the HDG, APU, or whatever...well, you're having a really really bad day and are probably careening toward the North Atlantic anyway. ;)
 
dasleben said:
Yeah, our 757-200s and 767-300ERs have the 90 minute standby systems and the HDGs (dunno why both). I think one of the 767s may only have the 30 minute batteries, but I'm not sure on that. Either way, if you're depending on the 30 or 90 minute batteries instead of the HDG, APU, or whatever...well, you're having a really really bad day and are probably careening toward the North Atlantic anyway. ;)
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Are you now with the contract carrier that starts with an O or an N?
 
DE727UPS said:
"The only thing that's going to run down the main battery in-flight is if you lose main AC and DC sources (both engines fail and you don't have your APU up yet) or you physically move the standby bus switch out of the AUTO position."

Following the checklist for standby power off, they moved the standby power selector to battery, which disconnects the battery charger from the system, even if it's powered. Then, the "battery discharge" light on the overhead panel comes on. This should have been their clue they needed to land within 30 minutes. That the battery powered the standby AC/DC, battery, and hot battery buss for 2.5 hours is remarkable. Perhaps there is more to the story about why that happened that I'm missing. But, in the end, the AA 757 battery failed and that's why they started losing systems on the standby buses, which is where the important stuff usually is. They lost trim capability which resulted in pitch control difficulty and probably the decision for the flaps 20 landing (faster speed so jet is less out of trim). I'm thinking blown tires on landing because of no antiskid. Then, the engines wouldn't shut down with the fuel control switches or fire handles (no power).

At that point I'd be running like hell away from this possessed airplane that won't do what I'm telling it. Check please.....
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Somewhat related - Do they still do a standby power landing in sim training? I'm legitimately curious how many of the malfunctions (in the book or otherwise) you wind up doing these days.

It's kind of sad that, in a situation that could require out-of-the-book and improvised action, American's guidance was "RTM, skipper." "Right, thanks for the help, but the situation isn't in the manual!"
 
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