AA 757 departed runway at ORD - no injuries

[lomapaseo]

....Read the goddam Report before sprouting such rubbish. A lot of perople died in this accident and if you don't understand what happened then their sacrifice (both the lives of the crew and passengers) are wasted and we are doomed to repeat history.

Please sick to the facts. We don't need a bunch of clowns going around sprouting self-opinionated or other political bull**** to try and change history so those extremely valuable lessons that we in the professional aviation community have learned at enormous human cost are simply denigrated.

This strikes me as little too vitrolic. We should not be looking back at accidents in a blame culture but rather forward in what we would do in the future. I have not interpreted anything that says that anybody intends to ignore the significance of cycling a rudder by command.

[IGh]

Relay-faults, annunciations, & Checklists

B737 cases offer some lessons regarding RELAY-to- Bus faults.

If you are fascinated by various electrical failure-interactions, you’ll enjoy reading the report from Danish AIB [HCLJ], re’ a B737 failure of a RELAY to the Battery Bus (this is an 18-page pdf with photographs of failed relay): the file http://www.aaiu.ie/upload/general/3582-0.pdf

“... The crew were not aware that they could reestablish normal functions and indications by switching STANDBY POWER (P5-5) to the BAT position , as the relevant manuals and checklists for the aircraft did not contain procedures concerning this problem....”

“... Furthermore Boeing explains that these incorrect and lacking indications will vary depending on the specific type of extra equipment installed ...

“... Boeing concludes its ... Bulletin by writing:
Boeing has no technical objection to an airline incorporating a loss of Battery Bus procedure in their Operations Manual. However, since there are so many different electrical configurations throughout the 737 fleet, Boeing is unable to publish a generic procedure in the Boeing Operations Manual which will work for all 737-300/400/500 airplanes.

EDIT -- Here's another B737 case:

AAIB Bulletin: 4/2006 G-EZYN EW/A2005/03/02
... Boeing 737-33V, G-EZYN
... 22 March 2005 at 1050 hrs

"... from Nice to Luton ... experienced progressive abnormal annunciator indications.... there were no procedures in the ... [QRH] ... a failure of a contact post ... the R1 relay ... power had been lost from this Busbar in flight.... no drills published for such a failure ... many different configurations of the electrical system in the Boeing 737-300/400/500 fleet have made it difficult for the manufacturer to produce a generic procedure for this failure, although they have provided information to enable operators to write a procedure for their own aircraft...."

These odd electrical mishaps highlight a manufacturer’s annunciation philosophy, and the operator’s associated checklist philosophy. If the aircraft model includes an EXPLICIT “alert” [eg, an annunciator or EICAS message for specific fault], then the QRH will include a crew response.

?? B757 “MAIN BAT DISCH” message/light ???

[Reviewing discussion in slots # 19 through #29 points up some details.]

IweinVanCaelenberg, in slot #116, you showed a crew’s QRH response to the B757’s “STANDBY BUS OFF” message. Once you switched the STBY POWER selector to “BAT”, wouldn’t you expect [???]:

-- the Standby Bus to be repowered, and thus the message (Standby Bus Off) to extinguish;

-- and then you’ld expect the “MAIN BAT DISCH” message to appear [???] sending you to that procedure.

The NTSB’s Preliminary report does NOT mention anything about any MAIN BAT DISCH message/light, but the Board’s Preliminary report does mention that lastly the “...flightcrew then reviewed the MAIN BATTERY CHARGER procedure referenced in the QRH....”

It could be that this victim-crew followed their QRH’s printed procedures to the letter.
It may prove ironic that AA had initiated an MD80 modification to add a “BATTERY CHARGER” annunciator (Overhead Annunciator Panel) as just such an explicit alert.

[SMOC]

Was there anything wrong with holding the checklist till TOD? Were there any system failures that needed to be restored immediately as a result of the standby bus off?

[bubbers44]

Why would you hold a checklist for TOD?

[SMOC]

When I flew the classic the F/Es during their bi-annual checks were always asked to understand the intent of the checklist and therefore the appropriate time to action it, or part there of in case of running multiple checklists that possibly overlapped. I must admit flying glass it's all to easy to jump straight in with the QRH or electronic checklist as soon as an EICAS/ECAM appears, as that's the way it usually works in the sim.

A case like this may have allowed the crew to say ok the STBY BUS is unpowered however the A/C is flying normally X,Y and Z are powered by it, but haven't failed at this point or have but are not required until decent/approach or landing therefore we have time to collect more information from the FCOM other manuals, engineering.

If it's obvious that the failure needs to be actioned immediately then it will and an immediate landing may be made.

It may have been possible to cycle the stby power switch to re-charge the batteries. Checklists cannot cover all scenarios and this is a good example which may result in a system or SOP/QRH change.

Crew did what they thought was right as they should, all safe and we get to learn something that may help in the future.

[bubbers44]

Flying a trip not having standby power doesn't sound very smart to me. Landing seems smart. 30 minutes of battery time is on a fresh battery. How fresh is the one in your aircraft? We can second guess what they did but why not just use the checklist and if it says you have 30 minutes just land. I think they actually tried to extend their trip to destination thinking they could deal with it on the descent but it didn't work. Some of those relay failure problems get pretty tricky.

[bubbers44]

Yes, I think going back to auto on standby power would have charged the battery up again probably losing the standby bus but no checklist says to do that and going to bat again on approach. They landed safely so maybe something will be learned from this incident.

[SMOC]

Also totally agree once your going down the battery road it's time to land. So again in this case it might be prudent to delay the checklist till within 30mins of landing, I used TOD as a point about 30mins out. If you choose to continue or are over the ocean then a good understanding of the intent of the checklist needs to be there so you don't run them flat.

[aa73]

Absolute Rubbish!

These statements are in direct conflict with the conclusions of the Accident Report (Aircraft Accident Report NTSB/AAR-04/04). In particular, read the evidence given by other AA flight deck crew who witnessed this FO previously performing "aggressive" rudder inputs in similar circumstances. When questioned, the FO defended himself by saying that "the AA Advanced Aircraft Maneuvering Program directed him to use to rudder pedals in that manner" (page 12 if you are interested).

Read the goddam Report before sprouting such rubbish. A lot of perople died in this accident and if you don't understand what happened then their sacrifice (both the lives of the crew and passengers) are wasted and we are doomed to repeat history.

Please sick to the facts. We don't need a bunch of clowns going around sprouting self-opinionated or other political bull**** to try and change history so those extremely valuable lessons that we in the professional aviation community have learned at enormous human cost are simply denigrated.

I fly for AA and am very well aware of the human cost. It's clear you put absolutely blind faith in an NTSB report without taking into account that sometimes hidden agendas and political plays affect the outcomes of investigations. If you don't believe me just remember TWA 800.

I attended AAMP when it was introduced and, while I disagreed with heavy dependence on the rudder in certain situations, merely getting out of wake turbulence was not one of them. Aileron first and then rudder to supplement, if necessary. Those are FACTS.

[Ignition Override]

As for the AA A-300 disaster, just after this crash, an aviation magazine ("Av. Week"?) described some unexplained rudder anomolies onboard some foreign airlines' A-300/A-310.
These happened with no pilot inputs on the rudder pedals.

Mentioned were former East German Interflug, Air France and possibly a third airline (Fedex?).
Pilots are such easy scapegoats when they are dead.

Oh well, back to the SKS and Mosin Nagant 44 websites .
Do most pilots have hobbies, or just Pprune?

[Shore Guy]

No editorial comment here…..per our manuals, these are the busses/items that would have been lost in this scenario…

Significantly, earlier B-757 aircraft had alternate stab trim “handles” that were direct cabled to valves.


HOT BATTERY BUS
Clock time references
Fire extinguisher bottles
Fueling system
IRS emergency power (R continuous, L & C for 5 minutes)
Landing gear alternate extension
Park brake valve
RAT manual deployment

BATTERY BUS
Alternate equipment cooling
Alternate stabilizer trim switches**
Antiskid system for inboard wheels
APU fuel valve
DC fuel pump
Engine anti-ice
Engine, APU and cargo fire detection
Engine driven hydraulic pump shutoff valves
Engine fuel control valves
Engine start controls
Forward cockpit dome lighting
Fuel crossfeed valve(s)
Fuel quantity system
Generator controls
Hydraulic PTU control
Interphone systems
Landing gear air/ground system
RAT automatic deployment
Spar fuel valves
Standby Engine Indication (SEI)

STANDBY DC BUS
Bleed air isolation valve
Electric stabilizer trim
Left aural warning speaker
Left stick shaker
Left VHF comm system
Left yaw damper*
Manual cabin altitude pressure control
Rudder ratio changer
Rudder trim
Stab trim shutoff valves
Standby Attitude Indicator

Rudder ratio changer***
Rudder trim
Stab trim shutoff valves
Standby Attitude Indicator

STANDBY AC BUS
Bleed air isolation valve*
Cabin altitude/differential pressure indications
Center ILS system
Engine ignition
Left navigation system (VOR, Air Data Computer (ADC) & RDMI)
Left yaw damper*
Main panel flood lights
Standby Instrument Panel lights
Three spoiler pairs
Wheel well fire detection
*Requires both AC and DC power to operate

[IweinVanCaelenberg]

relay faults etc...

IGh wrote:

IweinVanCaelenberg, in slot #116, you showed a crew’s QRH response to the B757’s “STANDBY BUS OFF” message. Once you switched the STBY POWER selector to “BAT”, wouldn’t you expect [???]:

-- the Standby Bus to be repowered, and thus the message (Standby Bus Off) to extinguish;

-- and then you’ld expect the “MAIN BAT DISCH” message to appear [???] sending you to that procedure.

Yep. And here it is. some procedure eh?

MAIN BATTERY DISCHARGE
message: MAIN BAT DISCH
condition: a main battery discharge occurs
----------------------

(The dotted line does mean end of checklist.) For all clarity: I am not passing any judgement on this AA crew or on any other for that matter. Only the stupid, the very lucky or the very inexperienced would do that and I am neither.

[layinlow]

Loss of power

An American Airlines 757 loses power shortly after takeoff. The pilot decides he can fly to New York on battery power alone. Gets as far as Chicago when more and more equipmrnt goes off line. Makes an emergency landing and does not have enough battery power left to shut downt he engines normally. Is that stupid or what? Who wants to bet his ticket is on the line?

[bubbers44]

They had a lot of electrical power left when they landed since both engine driven ac generators were working supplying everything but the four busses shown above. By selecting standby power to bat they removed the battery charger from the system and the battery went dead because it was supplying power to these busses.

[Junkflyer]

They had a lot of power, but you lose a lot without those buses including some pretty handy things like fire detection/protection.

[manrow]

But would the check list tell you that junk flyer

[bubbers44]

At that point in their flight I would have really liked antiskid, spoilers and stabilizer trim more than fire protection. That is what put them off the runway.

[sevenstrokeroll]

didn't fire protection exist for the engines...if they burned they would eventually fall off

apu in fire proof container

[bubbers44]

That would work but letting engines burn off aircraft isn't an approved procedure yet. Hopefully just following the procedure and time limits will work better.

[FlexibleResponse]

I fly for AA and am very well aware of the human cost. It's clear you put absolutely blind faith in an NTSB report without taking into account that sometimes hidden agendas and political plays affect the outcomes of investigations. If you don't believe me just remember TWA 800.

No, one doesn't have to have blind faith in NTSC reports and their conclusions, but NTSC reports do try to report the facts as accurately as is possible. However, most aviators would have very definite problems with folks who try to change the reported factual data to suit their own agenda.

I attended AAMP when it was introduced and, while I disagreed with heavy dependence on the rudder in certain situations, merely getting out of wake turbulence was not one of them. Aileron first and then rudder to supplement, if necessary. Those are FACTS.

This is not really relevant that YOU disagreed with the AA AAMP training as you were not the accident FO. The accident FO was reported for how HE felt about the AAMP and what the AAMP training directed him to do. If anyone is aware or has any evidence that the AA witnesses were lying about this, then they should send that information to the NTSB.

Every man and his dog on this planet are entitled to come to a different conclusion when considering the established facts of the NTSB report. That is a right and privilege of every man.

But, aviators generally don't like folks tampering with or trying to change the facts of an investigation, as they have found by bitter experience that in aviation, bull**** kills.