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Topic: CVR CB Pullout....When.
Username: HAWK21M
Posted 2012-12-17 11:24:54 and read 2768 times.

What is the SOP regarding CVR CB pulling out at the end of the flight....Out here we have two norms....For the B737 The CVR CB is pulled out after every Chocks on post Crew checklist readout,where as on the B757 it is pulled out only after chocks on & crew checklist completion after the LAST flight of the day/night.

Topic: RE: CVR CB Pullout....When.
Username: longhauler
Posted 2012-12-17 11:36:30 and read 2761 times.

Per SOP, we are never instructed to pull out a CVR or FDR C/B unless an incident is suspected. Then when we do, we must advise Maintenance Operational Control that the C/B is pulled.

Topic: RE: CVR CB Pullout....When.
Username: HAWK21M
Posted 2012-12-17 11:55:20 and read 2746 times.

Quoting longhauler (Reply 1):
Per SOP, we are never instructed to pull out a CVR or FDR C/B unless an incident is suspected. Then when we do, we must advise Maintenance Operational Control that the C/B is pulled.

What about long halts when power is switched off the Aircraft totally....

Topic: RE: CVR CB Pullout....When.
Username: CosmicCruiser
Posted 2012-12-17 12:13:49 and read 2740 times.

AS longhauler said we never mess with the CVR CB unless we want to preserve the tape due to a suspected incident.

Topic: RE: CVR CB Pullout....When.
Username: Dogbreath
Posted 2012-12-18 00:20:02 and read 2572 times.

Not sure what type of B737 you fly there HAWK2M, but on the B737-800, there is no requirement to open the CVR CCB after the final shutdown and for long ground stays.

The Flight Recorder has two positions, Auto and On, and is defaulted to Auto.
In the Auto position, the CVR will begin to record after the start of the first engine and will remain recording until 5 minutes after the last engine is shutdown. So there is no reason to open the CCB after the last shutdown.
The ON position (which is held in place by a solenoid) will begin the recording as soon as the switch is held in place (provided it is electrically powered). It spring loads to Auto during the start of the first engine, or when elec power is lost (ie. when shutting down elec power after the last flight).

In my airline's SOP, we select the Flight Recorder switch to ON when doing the pre-flight checks, so that the pre-flight and briefings are recorded, and again after we land and the engines are shutdown, so that the turnaround and subsequent briefings for the next leg is recorded.

Like a few other posters on here have written, any time the CVR CCB is opened a Tech Log entry must be made and the reason why it is opened reported.

Topic: RE: CVR CB Pullout....When.
Username: b78710
Posted 2012-12-18 09:50:07 and read 2457 times.

We have a quality notice to pull it after any reportable incidents.

And usually Maintrol will contact you when they want it pulled.

Not pulled at any other times

Topic: RE: CVR CB Pullout....When.
Username: HAWK21M
Posted 2012-12-18 22:49:34 and read 2365 times.

Quoting Dogbreath (Reply 4):
Not sure what type of B737

That was the B732F in those days.

Quoting b78710 (Reply 5):
We have a quality notice to pull it after any reportable incidents.

Thats done after any Incident reported to avoid rewriting on the CVR and data erasure.

BTW...The Parking brake set & erase button depress facility has to be deactivated out here due Regulatory requirement, by removing the erase supply/card at the module itself.This is not common in other places.

Topic: RE: CVR CB Pullout....When.
Username: TheCol
Posted 2012-12-19 02:13:10 and read 2340 times.

Quoting HAWK21M (Reply 6):
BTW...The Parking brake set & erase button depress facility has to be deactivated out here due Regulatory requirement, by removing the erase supply/card at the module itself.This is not common in other places.

Is that only exclusive for the 732F, or does that apply to all 732s in India? My employer operates 732s in a combi config, and, as far as I'm aware, the crews aren't normally required to pull the CB.

Topic: RE: CVR CB Pullout....When.
Username: HAWK21M
Posted 2012-12-19 02:44:07 and read 2332 times.

Quoting TheCol (Reply 7):
Quoting HAWK21M (Reply 6):
BTW...The Parking brake set & erase button depress facility has to be deactivated out here due Regulatory requirement, by removing the erase supply/card at the module itself.This is not common in other places.

Is that only exclusive for the 732F, or does that apply to all 732s in India? My employer operates 732s in a combi config, and, as far as I'm aware, the crews aren't normally required to pull the CB.

This mandatory modification issued by the Regulatory is required to be complied by ALL aircraft registered in the country.
The intent was to eliminate the erase of CVR recorded data.even the switch disconnection was not reccommended as a short could have still erased data,but required the Card to be removed from the CVR module itself.

Topic: RE: CVR CB Pullout....When.
Username: LimaFoxTango
Posted 2012-12-20 04:29:30 and read 2193 times.

In the Dash 8, the CVR starts recording as soon as power is applied to the aircraft. The FDR starts recording when the anti-col is turned on before engine start or weight off wheels signal.

Topic: RE: CVR CB Pullout....When.
Username: readytotaxi
Posted 2012-12-20 09:31:30 and read 2157 times.

Question, what happens to the box when an aircraft is parked in the dessert for X months, is the box removed after arrival or left in place until scrapping

Topic: RE: CVR CB Pullout....When.
Username: HAWK21M
Posted 2012-12-20 11:07:26 and read 2132 times.

Quoting readytotaxi (Reply 10):
Question, what happens to the box when an aircraft is parked in the dessert for X months, is the box removed after arrival or left in place until scrapping

An Aircraft that is parked under preservation schedule will retain the Module unless it is due for a shop visit.


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