A320 RMP ON/OFF Switch
 

Been noticing the practice of switching of all three RMPs specially by flight mechanics during ground stops, is there anything written on this matter?
this is accompanied by a compulsive swtching off of bearing pointers, screens, speakers and audio volume controls.

There is nothing in our manuals requiring that, but that doesn't prevent some crews from doing that as part of the securing checklist on those relatively rare occasions when airplanes are put to bed by flight crews rather than mx personnel.

That being said, there is nothing in our books PROHIBITING that either, so whatever floats your 70ft yacht, I guess...

Obsessive compulsive behavior, there is not other reason. Just like setting 0 feet in the altitude window before a crew change.

At my shop, we set 0 after landing as a reminder that we don't have a clearance for the outbound leg.

Not an issue here, initial cleared altitude is part of the SID and of course has to be set during cockpit preparation and confirmed by both during the departure briefing.

As usual, in the absence of clear instruction from the manufacturer, company SOPs must govern. I've never seen this mentioned before, but that does not mean that it has not been. Without clear direction from SOPs etc., crews that make up their own procedures and rules tend to get burned. Penko's suggestion and those of C.A. and Denti all have merit, but I simply do not want to go there.

Compulsive switching has been anticipated by Airbus.That is why in cockpit preparation SOPs mention RMP CHECK ON.

AFAIK Airbus OEM only says to dim the screens. For the previous 3 operators, this was only supplemented by a shared habit to turn the WXR radar intesity /ND - outer knob/ to the max whilst doing the above. And nothing more.

The present operator seem to have engrained crews with a non-written technique to set RMP OFF as well as to deselect the VOR/ADF switches to neutral. So now I am the one who leaves the cockpit untidy, apparently.

With my electronics hat on: Switching electronic things on and off shortens their life. The switch-off/on cycles stress the components. The fewer times this is done, the longer stuff will last. Also, most switches are mechanical in some way, so operating them more will wear them out more quickly.

Most television broadcasting equipment is left on 24/7. This is much gentler to the circuitry, and it lasts for years.

The only time I have seen RMPs turned off was during a turnaround and crew change on a very hot day in the Caribbean, when you could have fried an egg on the centre console !