Flying with the Carb-Heat on for a long(er) tour?

Peter,

Hey, your fuse is really short (so what else is new?) ;-)

You and I know that "Don't lean below xxxx feet" is one of the baddest,
wrongest, silliest (are those words?) OWTs (Old Wive's Tales) in
aviation. So, IMHO, we need to do all we can to keep it from getting
propagated. That's all I was trying to do.

--
Thomas Borchert (EDDH)

"Thomas Borchert" wrote in message
...
Hey, your fuse is really short (so what else is new?) ;-)

Yes, I have a low tolerance for people like you who see a need to label a
person wrong, no matter how much you have to stretch your interpretation of
what they said to do it.

You and I know that "Don't lean below xxxx feet" is one of the baddest,
wrongest, silliest (are those words?) OWTs (Old Wive's Tales) in
aviation. So, IMHO, we need to do all we can to keep it from getting
propagated. That's all I was trying to do.

Not that I could tell. The ONLY thing your post claimed was that not all
POHs provide an altitude below which one doesn't lean the engine. Which is
true, but in no way contradicts anything I wrote.

You made no comment whatsoever regarding actual operations. You only
contested your perception of what I wrote (which wasn't accurate anyway).

Pete

noah wrote:

Hi,
After taking two passengers on SF-Bay tours, I realized that I
want to take the tour slower... A north-bay tour (SF, GGB, Ocean
Beach, without the 101/Bravo transition) takes about 40min roundtrip
from OAK - a little quick.

I've been used to flying with the rpm around the bottom of the
green arc for this kind of thing, as my CFI used to always remind me
that "Carb-Heat introduces unfiltered air [into the carb]" which is a
bad thing...

Basically - is it bad for the aircraft (C172) to float around at
around 85kts with the power somewhere below the green arc (say
1800rpm) and the Carb-Heat on? Ok, there is a second benefit - my club
charges based on tach time, and I have to be honest about that -
although I really do wish for the tours to be slower.

The Cessna Pilots Assoc, in its systems and procedures courses,
reccomends that you use whatever amount of carb heat it takes to keep
the carb temp above freezing. You are doing no damage.

In article ,
(noah) wrote:


I've been used to flying with the rpm around the bottom of the
green arc for this kind of thing, as my CFI used to always remind me
that "Carb-Heat introduces unfiltered air [into the carb]" which is a
bad thing...

Basically - is it bad for the aircraft (C172) to float around at
around 85kts with the power somewhere below the green arc (say
1800rpm) and the Carb-Heat on? Ok, there is a second benefit - my club
charges based on tach time, and I have to be honest about that -
although I really do wish for the tours to be slower.

Just because you're RPM is below the green arc doesn't mean you'll
develop carb ice. In fact with a carb air temp gauge you might find
that at high power settings you're colder than at low power settings.

Try it without the carb heat. If you notice any roughness or RPM drop
apply heat.

The O-470 in a 182 makes more ice than most Frigidaires. I never flew
with the carb heat on constantly and I never had any carb ice problems.
I also had a carb air temp gauge.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

noah wrote:

Basically - is it bad for the aircraft (C172) to float around at
around 85kts with the power somewhere below the green arc (say
1800rpm) and the Carb-Heat on? Ok, there is a second benefit - my club
charges based on tach time, and I have to be honest about that -
although I really do wish for the tours to be slower.

No problem, but, as Peter says, lean the engine.

George Patterson
If you're not part of the solution, you can make a lot of money prolonging
the problem.

Thanks everyone for your replies...

Next time I'll fly with the rpm I want, and use Carb Heat below the
green arc as the POH recommends.

BTW: the Bay Tour definitely causes 'Ohh's and 'Ahh's. Even the first
two times I went (no pax) it was tough to stay focused on
traffic/airspace and not just enjoy the view. PS: Now (with pax) I
won't touch a camera at all, and just scan for traffic - as I've seen
quite a bit of traffic going North/South between the GGB and KHAF -
not to mention the low flying tours around the GGB and San Francisco.

Cheers,
Noah