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Old January 21st 05, 03:10 PM
Brian
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Ok, I am CFI, I have been flying about 16 years and have been a CFI for
about 8 years and have over 3000 hrs total with nearly 2000 hrs of
instruction given..

Here is my take on power off on downwind vs. carrying power through
base and final on normal landings (not short or soft)

I had instructors teach me both ways so when they handed me my
Instructor certificate I had to decide what was I going teach. I
primarily teach in Aeronca 7AC, Tomahawks and C-150's.

Here is my thinking on these approaches:

Carrying power through the approach makes the pattern larger and
longer, not necessarily a good thing in a slow Aeronca especially when
trying to do touch and goes with faster aircraft in the pattern.
However it does give new students more time to line up and stabilize
the aircraft on final approach. I do typically use this technique with
new students that seem to have difficulty controlling airspeed and/or
seeing the proper approach path.

Typically if the engine quit on Base while carrying power for the
approach you will not be able to glide to the runway(The bad news)
However you will know exactly when the engine quit and can start
emergency procedures immediately(The good news, I think) Pick your off
airport landing field possibly attempt a restart.

On the other hand if you try gliding from abeam the runway, if the
engine quits on Base you will probably not know that it quit (A wind
milling dead engine often looks and sounds just like an idling one)
However if you have set the approach up correctly you will probably
only discover that the engine died while you are rolling out on the
runway. Because of this issue if you suspect that you might be low,
don't hesitate to add power early and get high enough you are sure you
will make it to the runway. Another plus of practicing this method is
that you learn how to manipulate your pattern and airplane
configuration (Flap, Slips, etc) to make it your landing point without
power, which is excellent practice if you ever have to make dead stick
landing.


My thinking was, as an instructor I may be spending up to 60 hours per
week in the traffic pattern doing takeoffs and landings. My exposure to
a possible engine failure in the pattern is quite high. I would like to
minimize my chances of an off airport landing in the event of an engine
failure. Additionally If one of my students were to experience an
engine failure while solo in the pattern, I have a very high confidence
that they could land it on the runway from nearly any point in the
pattern once they turn downwind. I also would have no problem
explaining to a judge or jury that I started teaching power off
approaches (emergency procedure type) from our very 1st lesson. Also
the students are well practiced at power off approaches and setting up
to land at a designated spot without power so an off airport landing in
the practice area should not be to difficult if they had an engine
problem while doing ground reference maneuvers.

That being said there are many situations were power on approaches are
more appropriate than power off. Short and Soft field landing are a
good example, with power you can manipulate the power to precisely
clear an obstacle and touch down slower at a designated spot. If you
must do a short field landing, the chances of an engine failure are
probably less than the odds of you overshooting the runway. In this
case, carry power go out farther and insure you are not too high on the
approach.

Also larger aircraft (or small aircraft with a high wing loading,
homebuilts) come down very fast without power and require more skill
(or mostly speed) to land well power off. While you should practice
these in case of an emergency, it is probably not the best technique
for these aircraft. Also Shock Cooling becomes more of a factor in
larger engines, As a result my general rule of thumb I avoid frequent
power off approaches with engines having more than 400 cubic inches,
for this reason.

As is the case with many aspects of aviation, many of the procedures
that were designed for larger airline and military aircraft have been
passed down to our little single engine trainers. Many larger schools
have opted to train their pilots to fly these little aircraft like they
were large aircraft, with the thinking that most of these students will
soon be moving into larger aircraft. Unfortunately this training style
is trickling back to the rest the pilots that may never fly large
aircraft. Wouldn't be great if we required all instructors to have
about 50 hours in a Piper J-2 or a Curtis Jenny with a single Magneto.
I bet many instructors would learn a lot about flying smaller single
engine aircraft. Instead we are getting instructors that the smallest
airplane they have flown is a Cessna 172 and the were taught to always
land with full flaps and carry power through the approach like they
were landing a 707.

Hope this gives you something to think about how you fly your
approaches.

Brian
CFIIG/ASEL