Ah, one of those favourite cautionary tales, trotted out to back up an instruction of "don't touch that!"

Gibson's dive
http://en.wikipedia.org/wiki/TWA_Flight_841_(1979)

National Airlines DC-10 "pull the CB for N1 tach"
http://en.wikipedia.org/wiki/Nationa...ines_Flight_27

It is important to separate the folklore from the actual accidents. As alluded to above, the NTSB investigations were not beyond reproach. In the 727 slat incident, there was a presumption of guilt of the pilot in command. A witch hunt. The NTSB hypothesis was not supported by the subsequent test flight. In the DC-10 incident, the crew were castigated for a failure of discipline. However, the investigation revealed that the fan resonance that caused the uncontained failure of #3 would have remained undetected and happened at some future time.

What is relevant to the topic under discussion is ... the 727 "C/B pullings" are not applicable. IF the crew had pulled the Slat C/B, they were disabling a warning/protective system. It was a system that had limited interrelationships with other systems.

The DC-10 incident is a little closer. The crew hastened the incipient failure of the #3 by doing something the system designer never intended.

Current generation airliners have dropped most 'trouble shoot' procedures in abnormal checklists. Philosophy now seems to be - isolate the fault, then (a) land at nearest suitable aerodrome or (b) if conditions permit with the system disabled, continue.

AFAIK, the reason for replacing a troubleshoot QRH with an isolate then land at nearest suitable is the increasing complexity of the electronic (read micro computer based) control and command systems.

Pulling a slat C/B just used to disable the anti-extend mechanism.

Do that on a current generation airliner and you might disable the stall protection system and force the FADEC onto channel A which the EEC #2 previously set as FAULT, so FADEC then defaults to N1 mode instead of EPR, now autothrottles not available, etc... if you get my drift.

The benefit of all the digital electronics in flight control computers, ADIRUs, brake control units, proximity sensor units, is that they can monitor other systems for faults and failures and modify their status to suit. The drawback is myriad knock on effects for seemingly 'unrelated' system due to a fail/fault in one system, that never existed in second gen airliners.

Pulling C/B in flight? Only if QRH says 'do it' in response to an ECAM/caution/warning.

Pulling C/B on ground to reset computers due to fault indications?
"Incredibly dangerous, never never never!" or
"Its on the ground, and this handy guide has not let me down yet!"

I think the answer is somewhere in between.

Unofficial pilot notes were a good resource for thinking pilots, and a potential trap for the foolish and impatient. But so 'last century!' You now have unprecedented access to first hand advice via that mobile phone in your pocket. Iridium perhaps? HF even?

Call base. Speak to an engineer that knows the system. If he/she says 'give it a try' then go ahead. If he/she is reluctant, then you would be a mug for following your 'pilot notes.'

Don't have the MEL infront of me at the moment, but from memory if ADIRU 2 is U/S, take off cannot be performed in Config 1+F. How on earth can failure of such a seemingly unrelated system have that effect ?

Answer - If erronious airspeed indications were recieved there is nothing for the flap overspeed protection to compare with, and the flaps could retract at the wrong time. One incidence of this happening I think.

What about those spurious ECAM warnings that occasionally come up and disappear all by themselves, also the STS message which pops up briefly but you are never quick enough to push the button to view it before it vanishes.

Welcome to third generation airliners.

How on earth can failure of such a seemingly unrelated system have that effect ?

Not speaking to the context, but this is the generic problem with applying the MEL to multiple problems out in the field ...

I was looking for a better version and I found an app that is available for both Android and iOS. ECAM Resets+ It appears to be kept very up to date and from what I can see completely reflects the Airbus fault-finding workflows.

Apple Store

Android Version

When you guys reset CBs do you enter the defect in the log and quote chapter and verse from the current revision of the AMM/TSM?
Because, when Engineers and Mechs get hauled over the coals by the national regulator and local quality departments because they didn't dot the 'I's and cross the' T's this sort of discussion really sticks in the throat! 🙄😞

Mmm, more like welcome to Airbus!!

Yes. eg “LGCIU 1(2) reset in accordance with QRH ref XYZ. Successful/Unsuccessful. Signed: Capt Roger Victor, Date:17th Dec. 1903”

Mobile Tech
try this. Usual caviats apply.

I can honestly say I've never seen a write up anything like that.

This one?

ELAC 1 PITCH FAULT displayed during F/CTL checks. Reset i.a.w QRH PROC successful, no further warnings.

We used to have “info only” write ups for that but pilots kept making too many mistakes, so now mx control needs to be informed, and they keep track. Don’t like not seeing the history in the book. Having said that, just found an “Info only” for an unsuccesful autoland (facepalm) on an airplane that flew for 2 more days without getting downgraded.

Hence is why the info only was banished where I came from with the 2nd generation of western trained pilots.

The guys were actually on the first courses but as bright-eyed FOs then.

Because info only means exactly nothing specific. For many years the QA, which is much more strict for MX than flight ops here, does not recognze a semi-writeup.

Either its there or not, if yes will be responded to. 'Recorded as per CAMO Manual'. No, does no work well on an outstation or chain schedule downroute unless CAMo Manual and TechLog procedures are ready for it. That needs a bit of forward thinking by the certifying NAA.

The administration part is a pain, not the procedure itself. With cloud TechLogs and electronic signatures this can be overcome but the RoI on that investment is hard to justify (not to calculate, rather to push past the CFO).

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Back in the early days of the A320 family there was a procedure to pull certain cb to extend the flight time on battery only to 60mins and the cb had yellow collars.Is this true or am I thinking of another bus?

Correct tubby. One of our fleet still has it (MSN 10xx). Not well understood by all on the fleet.

Thank you for the reminder jwscud. I had a break from the A320 fleet and when I went back the early sn aircraft had gone as had the collared cb on the over head panel.

LGCIUs, ELAC fault described by Flight Detent , BSCUs... they all require, by QRH, to write up the reset, even if successful. I think there's a couple more in there somewhere