Prop to High RPM on downwind

In article ,
Roger wrote:

On Sun, 28 Nov 2004 04:39:45 GMT, Orval Fairbairn
wrote:



Exactly, except for those airplanes that cannot maintain level flight at
pattern speed with gear and flaps out at final descent power settings.


You should hear me on a circle to land. Gear out, bout 20-25 deg of
flaps and go to cruise power until within about 30 degrees of the
landing runway heading. Then back to about 12" and full flaps. Turning
with everything hanging out while maintaining altitude takes about
22-23" of MP at 2400 RPM. At that power setting and low altitude
~500' AGL I try to keep it over the airport for the full circle to
land.

I much prefer the 360 overhead pattern:
Circle to land is an instrument procedure. 360 overhead is not an
option. I was commenting on the noise aspect. Also you are required
to maintain at or above MDA until within about 30 degrees of the
runway. (which can be about half the VFR pattern altitude.)


A properly done 360 overhead is quiet, as power is reduced over the
runway.



In the Deb the recommended approach speed is 120 while the VFR pattern
is *usually*: slow to 100-110 on down wind, gear down at the end of
the runway,. Flaps 10-15 degrees, MP about 12 to 14" until gear
down. base 90 with 20-25 degrees of flaps, final is 80 minus 1 MPH for
each 100# under gross which for me is normally around 75 -76 MPH. MP
is around 10" (give or take) and produces a steep descent "Prop on
final", Flaps go full usually just prior to the round out. There is
no trim change with flaps and by the time I reach the round out it's
usually full nose up trim.


1) flying at cruise down the runway at pattern altitude from about 2
miles out (Initial) to just past the threshold,

Doesn't that put you at odds with other traffic on cross wind or
departing? I hit pattern altitude right at the end of the runway on
climb out. (3800 ft runway) and we'd be in each others blind spots.

Nope -- headon traffic is on downwind -- away from the runway. You are
able to monitor downwind traffic as you approach the airport. If any is
there, you either break behind them or carry through and re-enter. Break
is preferable over the threshold.


I almost took a plane head on at MOP while on an instrument approach
when he turned upwind over the runway at pattern altitude. I was
under the hood and all I heard from the instructor was, "Ohhhhh ****!
Pull up! Pull UP!". I hit the power and bout stood the old Deb on
end, bringing the nose down to hold Vx. He never would tell me how
close we were, but I did gather it was a matter of only a few feet.

You were doing a downind approach?



I thought the 360 overhead with the break was done above pattern
altitude.

Nope. Pattern altitude or "popup" to exchange altitude for speed. It is
also easier to see traffic from below, rather than picking through
ground clutter.


2) break to downwind (traffic permitting), pulling power as you break,

3) Keeping at least 45 deg bank, drop gear and flaps when appropriate
speed is reached (usually at the 180 deg point),

4) slow to approach speed, while turning and keeping TD point in sight,

5) touch down on full 3-point attitude on the numbers.

In a nose dragger?:-)) Albeit I usually touch down in the
appropriate attitude for a 3 point in a tail dragger. When I flew
with an AirSafety Foundation instructor he asked if I flew tail
draggers a lot after my first full stall landing.

Nor am I a proponent of touching down on the numbers unless it's a
short runway. Except on short runways I go for the touch down zone.
If it's a log way to the first turn off I ask to land long.

It's a matter of choice. The old chestnut about "runway behind you, blue
sky above you, ...etc."


Properly done, you don't add power any time after the break -- it is a
continuous circle to touchdown. It is the easiest way to recover a
formation -- each plane breaks at 2 - 4 second intervals. I do this all
the time in my Johnson Rocket; I have done it in a Zlin 242 and a
friend's big-engined T-34. The whole "pattern is within a 1/4 to 1/2

The Deb is just a streamlined T34 with a door instead of a sliding
canopy. (It doesn't get airstream separation over the vertical stab
due to the canopy like the T-34) However a typical final takes a bit
of power. Power off is faster and uses quite a bit more runway. To
quote the POH, the extra speed when power off is to add enough energy
to flare. Power off is 90 to 95 while power on is 80 minus the one MPH
for each 100# under gross which makes for a much steeper descent and
shorter roll out. That extra 10 to 15 MPH will pretty much double the
required runway.

mile of the runway.

Prop goes in when you reach approach speed.

As most of my VFR pattern is decelerating I have no need to add power
and as the MP is low enough the prop control is no longer controlling
the RPM... Unless you pull it way out . I also fly a very tight
pattern, but try to keep it conventional due to a lot of students in
the pattern. They get a big enough surprise with instrument
approaches that come in at half their altitude.

Procedures vary according to traffic conditions.

OTOH I do not do the tight, steep approaches when carrying passengers.
Those are the gentle turns with gentle descents.

I do fly the occasional, stabilized pattern, but prefer to vary each
time which helps to know the airplane. If I do a stabilized pattern I
will have to add power as in the circle to land.


True -- that is one of the problems with the "stabilized approach."
Pilots trained with that procedure would be in a heap o' hurt if the
engine fails. Around here there are several flight schools (including
ERAU) that fly 747-type patterns in C172s. Net result is extended
patterns and noise complaints from neighbors.