Some suggest that you should switch tanks every 30 so that if one was to become unusable for any reason, then you find out about it while you still have plenty in the other tank
The reason the fuel is unusable will be because the cock has jammed, fractured, sheared off........it really is the weak point in the fuel system. Well the gascolator is of major concern also of course. - they literally are hanging in there by a thread...... and a very sloppy one these days. These items are all that a seperating you from a fuel starvation issue.
change tank 30 min after take off and then every hour after that. When its only using 30lph (22kg) their really isnt much point changing every 30min, never any balance issues,
I do basically that. fly until the end of the good terrain on the right tank (20 or 30 mins), change at the last landing point..... and then fly the remainder on the left tank.
On a Tomahawk that is 2 1/2 hours flying.... changing only once, no imbalance issues and I know that the 2 plus hours in the right tank is still there.
Crossing any large body of water requires a little planning, I plan the fuel management about that. Basically doing the change to the full tank at least 5 minutes prior to leaving land...... and touching nothing until reaching land again.
Some aircraft have notoriously unreliable fuel systems...... I have seen guys setting off on ferry flights in the likes of an Islander and returning because the tip tank valves didn't operate. Sure the little electric switch clicked up.....
I was thinking about all the flying instructors I have met or flown with..... and then judged their knowledge of the fuel system. I suspect there was one that knew his aircraft.....
Don't start me on some of the others. A schematic in a POH is exactly that...a schematic, simplified, - and still some would struggle with it.
I have yet to meet a 'bad' pilot.... could it also be that 'good' fuel management is actually not that CRASH hot also.
I do know I got a got deal on an aircraft purchase after a PPL showed his proficiency in fuel mismanagement and precautionary landing techniques.....
Brilliant.