Master Switch problem
 

Hi,
I'm due to take a rental grumman tiger away next week for several days. It has an intermittent problem where the electrics still work when the master is OFF.
The mechanic has not been able to replicate the problem and says it's okay to take away on the trip.
I'd appreciate some thoughts on what risks I might be taking if I accept the mechanics assessment fly the plane.
Thanks

Sticky main relay?

Thanks. I'll ask the question.

Risk of running the battery flat. Are the mags live when this problem appears ?

Magnetos should not be affected,,,

Correct; the whole point of magnetos is that they are totally independent entities and not connected to the battery/charging system.

Not very likely but, if you had an electrical fire on board, you'd want to want to knock off electrical power before then trying to work out what cct was causing the fire so you could at least get a few things back on-line. Just something to add to the list! :ok:

Some have been mentioned already:
- Risk of running the battery flat. Try to organise your flights so that you are overnighting at an airfield where you can get a jump start in the morning.
- In an emergency you will not be able to switch everything off by switching off the Master Switch. You may be able to achieve the same by switching off individual components and/or pulling circuit breakers (if they're the type you can pull).
- Check whether any components are directly connected to the battery bus (they should not be). Make sure all the other switches are operational, so that you can switch off all lights (internal lights are sometimes forgotten), all the avionics and all other electrically powered stuff.
- I am not familiar with the type, but have a look if any electrically powered equipment is essential for your flight(s). You will be running a slightly higher risk of electrical problems (it's not a significantly higher risk, most likely, but it has increased) so make sure that if the brown stuff hits the rotating blades, you do not lose anything that you will be relying on.

That's all I can think of right now.

Don’t sweat it, you can just pull over to the Curb (Kerb) if something bad happens, right?

What the hell are you thinking?
You are an incident waiting to happen.
Taking off in an aircraft with such a defect is idiocy.

If the darned thing catches fire and you can’t shut off the electrical system, and the insurers find this thread, those who you leave behind will suffer penury.

Very early on in my flying career I was told: “Always consider how your actions would read in the subsequent report.”

Did you ask the `mechanic` to go with you....?

Thank you
 

Thanks for all the replies. They are all appreciated, even the direct ones :).
I was asking 'if' I accept the mechanic's advice. I was wanting to see if there was anything i had not considered in my own assessment of the situation.
I've already said no to the owner.