"Peter Duniho" wrote in message
...
"Bob Gardner" wrote in message
news:_tkec.120289$K91.333719@attbi_s02...
It's common sense, when you think about it. With both halves of the
switch
ON, the alternator field windings are connected across the battery,
creating
a drain in addition to that drawn by the starter

It's worse than that, too. Not only is the battery being used to energize
the alternator field circuit, but having that circuit energized creates
drag
on the engine, making the starter work harder.

It makes sense to me, too, but I've always been told to follow the
procedures in the POH. My 172 POH's don't contemplate the split switch
start. Also, I'm concerned that if I change my routine now, I'll be taking
off with a rapidly draining battery one day.

Having said that, I split the switch to do the flaps and lights check early
in the pre-flight.

-- David Brooks