A320:Smoke Procedure

[stalwart2010]

Hello everyone,

In QRH smoke procedure checklist there is a precondition-If smoke disappears within 5mins-Normal Ventilation restore.
I am unable to understand when is this precondition applicable-Is it applicable after the immediate actions and what items are to be restored in nomal ventilation.

[pineteam]

Hello,

I suggest you have a read on the Airbus Safety First #15 from February 2015. You google it and can download for free. There is an article about Smokes Procedures.

From what I understand: After troubleshooting if no more perceptible smoke within 5 minutes, you can reset the ventilation blower, extract and cabin fans. These were reconfigured to prevent smoke recirculation and for crew protection. If smoke disappears then you should set them back to normal.

Edit: If you go on “Win Airbus” they also have made a couple of videos on how to deal with smokes.

[CrazyStuntPilot]

From a conversation I had with Airbus a while ago:

The 5 minutes period mentioned in the smoke/fumes procedure comes from the original design of the AVIONICS SMOKE ECAM alert, which included a 5-minute timer on older Flight Warning Computers (before and until FWC F4). This older procedure referred to a 5-minute countdown during which the flight crew had to perform troubleshooting to identify the source of the smoke. If the smoke was no longer detected in the avionics bay, before the countdown reached 5 minutes, then the AVIONICS SMOKE ECAM caution disappeared. And if the countdown reached 5 minutes and smoke was still detected, the AVIONICS SMOKE ECAM was latched, remaining displayed on the ECAM (even if after that, the source of the smoke was discovered and stopped).

Since then, Airbus has modified this ECAM logic so that the countdown is removed from the AVIONICS SMOKE ECAM procedure. Feedback has shown that, depending on the smoke scenarios, this 5-minute threshold was not always applicable: in some cases, it was more appropriate to set the electrical emergency configuration well before the 5-minute period, as the situation was deteriorating rapidly. In other cases, even though the smoke source had been isolated, more than 5 minutes were necessary to clear the smoke from the detectors.

The 5-minute requirement to restore normal ventilation was introduced in the Smoke/Fumes procedure to ensure consistency between the various smoke procedures.

However, taking into account the diversity and the complexity of the smoke scenarios, only the flight crew is in a position to assess the situation and to take the decision to restore the ventilation, if they have determined that the source of the smoke has been isolated.

The condition: "If smoke disappears within 5 minutes: NORMAL VENTILATION . . . . RESTORE" requests the flight crew to restore the ventilation system if the smoke disappears within a 5-minute timeframe after the smoke is detected.
The items to restore are the pushbutton switches on the VENTILATION overhead panel: BLOWER, EXTRACT, CAB FANS.

[stalwart2010]

Originally Posted by pineteam

Hello,

I suggest you have a read on the Airbus Safety First #15 from February 2015. You google it and can download for free. There is an article about Smokes Procedures.

From what I understand: After troubleshooting if no more perceptible smoke within 5 minutes, you can reset the ventilation blower, extract and cabin fans. These were reconfigured to prevent smoke recirculation and for crew protection. If smoke disappears then you should set them back to normal.

Edit: If you go on “Win Airbus” they also have made a couple of videos on how to deal with smokes.

Thank you so much for your reply and the references.its a good source of information

[stalwart2010]

Originally Posted by CrazyStuntPilot

From a conversation I had with Airbus a while ago:


The condition: "If smoke disappears within 5 minutes: NORMAL VENTILATION . . . . RESTORE" requests the flight crew to restore the ventilation system if the smoke disappears within a 5-minute timeframe after the smoke is detected.
The items to restore are the pushbutton switches on the VENTILATION overhead panel: BLOWER, EXTRACT, CAB FANS.

Thank you for your reply
.So I understand that 5 mins timing is only applicable to Avionics smoke procedure after the initial actions? or its applicable to other sources ie)packs and cabin equipment?The way this precondition is placed in the QRH is a bit confusing.

[CrazyStuntPilot]

Originally Posted by stalwart2010

Thank you for your reply
.So I understand that 5 mins timing is only applicable to Avionics smoke procedure after the initial actions? or its applicable to other sources ie)packs and cabin equipment?The way this precondition is placed in the QRH is a bit confusing.

No. it is applicable to ALL sources.

[dream747]

Right after LAND ASAP red in the procedure, it says “if perceptible smoke apply immediately” the procedure.

Seeking some opinions on how do you guys interpret “perceptible smoke”. Does invisible smell/fumes that cause physiological effects considered as perceptible smoke this case? Or does Airbus refer this as any kind of fumes/smoke/smell?

[sonicbum]

Originally Posted by dream747

Right after LAND ASAP red in the procedure, it says “if perceptible smoke apply immediately” the procedure.

Seeking some opinions on how do you guys interpret “perceptible smoke”. Does invisible smell/fumes that cause physiological effects considered as perceptible smoke this case? Or does Airbus refer this as any kind of fumes/smoke/smell?

FCTM
The smoke or fumes are perceptible if the flight crew can confirm it visually or by smell.

[CrazyStuntPilot]

Originally Posted by sonicbum

FCTM
The smoke or fumes are perceptible if the flight crew can confirm it visually or by smell.

correct. This requirement comes from the 320 family AVIONICS SMOKE ECAM alert which is incorporated into the QRH. This check is required on 320 family aircraft because the avionics smoke sensor can trigger spurious avionics smoke alerts.