Carb heat: my new policy. Any comments

wrote:
On Sep 8, 11:51 am, Dudley Henriques wrote:

I'd say a vast amount of engine "hiccups" on a go around are caused not
by carb heat but rather by over aggressive use of throttle. SMOOTH is
the key word for throttle use on a go around. Aggressive throttle use
might get you a "hiccup" in a 150 Cessna. It might even cause an engine
failure. It can kill you in a high performance prop airplane.


The hiccup is only one part of the risk when shoving the
throttle in too fast, too. When high manifold pressures are applied at
low RPM, the cylinder pressures get much too high and detonation
becomes a danger. Broken pistons and rings and other cylinder parts
can all result from this, as can overloaded bearings. The propeller is
a very heavy flywheel and we can't expect the same acceleration we get
in our cars. Further, even old cars had variable ignition timing that
would drop the spark advance to 10 or 6 degrees BTDC during
acceleration to avoid detonation, but our LyConts don't have that and
are stuck at 20 or 25 or 28 or whatever degrees. The pilot will never
hear the pinging because of all the other racket, but it's there if
they get too rough with the throttle.

Dan

As a pilot of Warbirds through the years I've run into the problem
consistently when advising new pilots on how to handle these airplanes.
Some SE warbirds will actually torque roll if high MP is applied on a go
around with the prop in full increase (Low pitch/high RPM), if the power
is ham handed in with the airplane under about 120 with high AOA
involved in the power up equation.


--
Dudley Henriques

"Dudley Henriques" wrote in message
...
wrote:
On Sep 8, 11:51 am, Dudley Henriques wrote:

I'd say a vast amount of engine "hiccups" on a go around are caused not
by carb heat but rather by over aggressive use of throttle. SMOOTH is
the key word for throttle use on a go around. Aggressive throttle use
might get you a "hiccup" in a 150 Cessna. It might even cause an engine
failure. It can kill you in a high performance prop airplane.


The hiccup is only one part of the risk when shoving the
throttle in too fast, too. When high manifold pressures are applied at
low RPM, the cylinder pressures get much too high and detonation
becomes a danger. Broken pistons and rings and other cylinder parts
can all result from this, as can overloaded bearings. The propeller is
a very heavy flywheel and we can't expect the same acceleration we get
in our cars. Further, even old cars had variable ignition timing that
would drop the spark advance to 10 or 6 degrees BTDC during
acceleration to avoid detonation, but our LyConts don't have that and
are stuck at 20 or 25 or 28 or whatever degrees. The pilot will never
hear the pinging because of all the other racket, but it's there if
they get too rough with the throttle.

Dan

As a pilot of Warbirds through the years I've run into the problem
consistently when advising new pilots on how to handle these airplanes.
Some SE warbirds will actually torque roll if high MP is applied on a go
around with the prop in full increase (Low pitch/high RPM), if the power
is ham handed in with the airplane under about 120 with high AOA involved
in the power up equation.


--
Dudley Henriques

Oh brother, here we go again.

Lonnie wrote:
"Dudley Henriques" wrote in message
...
wrote:
On Sep 8, 11:51 am, Dudley Henriques wrote:

I'd say a vast amount of engine "hiccups" on a go around are caused not
by carb heat but rather by over aggressive use of throttle. SMOOTH is
the key word for throttle use on a go around. Aggressive throttle use
might get you a "hiccup" in a 150 Cessna. It might even cause an engine
failure. It can kill you in a high performance prop airplane.

The hiccup is only one part of the risk when shoving the
throttle in too fast, too. When high manifold pressures are applied at
low RPM, the cylinder pressures get much too high and detonation
becomes a danger. Broken pistons and rings and other cylinder parts
can all result from this, as can overloaded bearings. The propeller is
a very heavy flywheel and we can't expect the same acceleration we get
in our cars. Further, even old cars had variable ignition timing that
would drop the spark advance to 10 or 6 degrees BTDC during
acceleration to avoid detonation, but our LyConts don't have that and
are stuck at 20 or 25 or 28 or whatever degrees. The pilot will never
hear the pinging because of all the other racket, but it's there if
they get too rough with the throttle.

Dan
As a pilot of Warbirds through the years I've run into the problem
consistently when advising new pilots on how to handle these airplanes.
Some SE warbirds will actually torque roll if high MP is applied on a go
around with the prop in full increase (Low pitch/high RPM), if the power
is ham handed in with the airplane under about 120 with high AOA involved
in the power up equation.


--
Dudley Henriques

Oh brother, here we go again.


Well hello Max. What took you so long? :-)

--
Dudley Henriques