On Mar 4, 10:57 am, "Darkwing" theducksmail"AT"yahoo.com wrote:
wrote in message

...



I just read an interesting argument by Lew Gauge in his E-185 Bonanza
book.

Some background -- the older Bonanzas (straight 35) have a "Flap"
switch. There's no increments unless you stop the motor as the flaps
are being dropped. Apparently it's hard on that design to start-stop
the motor.

Lew said there's no reason to teach incremental flaps in small
airplanes -- and that multiple flap applications just add to the
workload with no advantage-- apply 10 degrees, trim, apply 10 more,
trim, etc.

His argument is that if the sequence is always the same -- gear down,
trim, flaps down, trim -- the approaches will be consistent and reduce
the likelihood of a gear-up landing (since the descent profile with
15" MP and full flaps gear up is very close to 15"+ full flaps + gear
down).

The more I think about this the more it makes sense, except in the
partial flap case (though an argument can be made that there's no
reason to ever go partial -- but that's another topic).

I'm sure this will be contentious, but isn't that the point?

Dan

I think there are advantages to incremental flaps in the pattern because you
are in different phases of flight in speed and angle of turns. By the time
you turn final you need to be at basically landing speed and established on
a stabilized approach, if you jam all the flaps in and try to get a nice
angle for the approach with a stabilized airspeed you are just creating more
work in a shorter amount of time.

OK, but the counter argument is -- Why have different airspeeds?

In a model 35, Vle is 100 MPH (pretty slow). So I get the airplane to
90 on downwind, drop the gear midfield. At the numbers drop full flaps
and turn to base at 80, to final at 80, and then slow to 65-70 on
final (depending on winds). The slowdown on final requires very little
power-attitude-configuration change (a little nose up trim), and thus
I can concentrate on good turns and traffic scans during the turn to
base, turn to final critical phases of flight.

The pitch change in the 35 as the flaps drop to full is negligible,
but the descent rate with 15" MAP goes from straight and level to 700
FPM with no speed change. Trim up to a descent rate is 500' FPM and
target airspeed of 80 MPH.

Dan



This