Michael,

What do you experience that causes you to have to enrichen your
mixture as you descend on your airplane? Are you descending while
carrying a very high power setting? I'm asking because I've flown
T182s and TR182s and have never run into a situation that required
enrichening the mixture during descent unless I leveled off at some
intermediate altitude and went to a relatively high power setting.

Otherwise, the only reason to enrichen the mixture during descent is
if the engine actually begins to run roughly. (See the POH which only
recommends enrichening if you experience engine roughness.) Most
people descend at 65% power or less, which means that it is impossible
to detonate the engine due to lack of heat and pressure, so it's
impossible to run it too lean (it will simply start to run rough and
then quit if you get it too lean, you won't hurt anything). Keeping
it leaned during descent helps avoid overcooling (if you believe in
shock cooling), helps keep the plugs from fouling and doesn't waste
fuel. In general, once you lean the engine for cruise on a T182 you
needn't touch the mixture control until you pull it to idle cutoff
after landing, or to go to full rich on a go around.

All the best,
Rick

"Michael 182" wrote in message news:KXjMb.26563$5V2.40699@attbi_s53...
Are you sure about this? I always have to enrichen the mixture as I decrease
altitude.

Michael


"john smith" wrote in message
...
Barry Klein wrote:

How should we have found the correct mixture setting
for power-off final approach, when the turbo is basically adding no
boost and we are at high density altitude?

Did you enrichen the mixture between cruise and landing?
There should have been no reason to. As you reduce altitude and MP, the
mixture will enrichen with decrease in altitude. Had you need to do a go
around, the cruise mixture would have been sufficient for a full power
go-around.