Turbo 182: correct mixture for final approach at high altitude?

"john smith" wrote in message
...
[...] Had you need to do a go
around, the cruise mixture would have been sufficient for a full power
go-around.

You do understand that he's talking about a turbocharged engine, right?
Generally speaking, full rich is the correct mixture setting for a
turbocharged piston engine, for full-power takeoffs regardless of altitude.

Pete

Peter Duniho wrote:

You do understand that he's talking about a turbocharged engine, right?
Generally speaking, full rich is the correct mixture setting for a
turbocharged piston engine, for full-power takeoffs regardless of altitude.


'Generally speaking', but not necessarily. Full-rich is the correct takeoff
setting for a FUEL-INJECTED engine regardless of altitude, but *not* for a
CARBURETED engine.

Most turbocharged engines are injected, but not all. In fact, the Turbo 182 has
one that isn't: a (carbureted) Lyc 0-540.

Really - my carbureted 182 calls for full rich on takeoff

"Mark Mallory" wrote in message
...


'Generally speaking', but not necessarily. Full-rich is the correct
takeoff
setting for a FUEL-INJECTED engine regardless of altitude, but *not* for a
CARBURETED engine.

Most turbocharged engines are injected, but not all. In fact, the Turbo
182 has
one that isn't: a (carbureted) Lyc 0-540.

Michael 182 wrote:
Really - my carbureted 182 calls for full rich on takeoff

So does mine - at SL on a standard day.

But not on a hot 95 degF afternoon at 5000 MSL.

"Mark Mallory" wrote in message
...

Michael 182 wrote:
Really - my carbureted 182 calls for full rich on takeoff

So does mine - at SL on a standard day.

But not on a hot 95 degF afternoon at 5000 MSL.

What's the critical altitude of the turbocharged engine in your airplane?
Is it above or below the density altitude for that 95 F at 5000'?

As long as you are taking off at full power, I see no reason why you would
not use full rich mixture. Conversely, if even with the turbocharger, you
cannot make full power, I can believe one would need to lean.

I don't see why the difference should be between fuel-injected versus
carbureted. The metering is basically the same for both; only the method of
delivery is different.

Pete

Peter Duniho wrote:

"john smith" wrote in message
...
[...] Had you need to do a go
around, the cruise mixture would have been sufficient for a full power
go-around.

You do understand that he's talking about a turbocharged engine, right?
Generally speaking, full rich is the correct mixture setting for a
turbocharged piston engine, for full-power takeoffs regardless of altitude.


Yes, I remembered the turbo part this afternoon.
For descent there is no reason to change the mixture unless you are
going to push the throttle back in beyond the cruise power setting.
For takeoff, the turbo should maintain sealevel power up to 12,000 feet
MSL, so full rich or slightly leaned mixture would be used on takeoff. I
think I would still lean for best power prior to releasing brakes for
takeoff.

"john smith" wrote in message
...
[...]
For takeoff, the turbo should maintain sealevel power up to 12,000 feet
MSL, so full rich or slightly leaned mixture would be used on takeoff. I
think I would still lean for best power prior to releasing brakes for
takeoff.

You need to use full rich to keep the exhaust temperature down. With the
turbocharged engine I normally fly, in my airplane, about a third of the
fuel is used just for cooling (30 gph at full power, when theoretically only
about 20 gph would be needed for the 270 hp). The turbocharger controller
ensures that I am getting best power, without any fiddling with the mixture
at all. Even in an aircraft with a manual wastegate, one would ensure best
power using that control, not the mixture.

Pete