Seems if one must use full flaps AND slip in landing, I would say the
approach was an abortion that lived. I prefer slips to flaps as you can
instantly remove a slip but the same can't be said for flaps...

Just MY personal opinion...not trying to slam anybody.

Scott


Bob Moore wrote:
Bertie the Bunyip wrote

This examiner had had a fright in a 172 and
did not alow anyone to slip with flaps out.
While I am firmly in the camp that says some
cessnas can get a litle fuzzy in pitch with
full flaps, this is just stupidity incarnate.


About once-a-year I post the following excerpt from "Cessna, Wings for
the World", a book by William D. Thompson.

Bill Thompson is an Aeronautical engineer from Purdue University and
worked for Cessna Aircraft Company for 28 years as an engineering test
pilot and later as the Manager of Flight Test & Aerodynamics.

-------------------------------------------------------------------
"With the advent of the large slotted flaps in the C-170, C-180, and C-
172 we encountered a nose down pitch in forward slips with the wing
flaps deflected. In some cases it was severe enough to lift the pilot
against his seat belt if he was slow in checking the motion. For this
reason a caution note was placed in most of the owner's manuals under
"Landings" reading "Slips should be avoided with flap settings greater
than 30° due to a downward pitch encountered under certain combinations
of airspeed, side-slip angle, and center of gravity loadings". Since
wing-low drift correction in cross-wind landings is normally performed
with a minimum flap setting (for better rudder control) this limitation
did not apply to that maneuver. The cause of the pitching motion is the
transition of a strong wing downwash over the tail in straight flight to
a lessened downwash angle over part of the horizontal tail caused by the
influence of a relative "upwash increment" from the upturned aileron in
slipping flight. Although not stated in the owner's manuals, we
privately encouraged flight instructors to explore these effects at high
altitude, and to pass on the information to their students. This
phenomenon was elusive and sometimes hard to duplicate, but it was
thought that a pilot should be aware of its existence and know how to
counter-act it if it occurs close to the ground.
When the larger dorsal fin was adopted in the 1972 C-172L, this side-
slip pitch phenomenon was eliminated, but the cautionary placard was
retained. In the higher-powered C-172P and C-R172 the placard was
applicable to a mild pitch "pumping" motion resulting from flap
outboard-end vortex impingement on the horizontal tail at some
combinations of side-slip angle, power, and airspeed."
--------------------------------------------------------------------
1959 C-172
Notice that this prohibition appears in Section III, Operating Details
of the C-172Owner's Manual and NOT in Section IV, Operating Limitations.
It is NOT an FAA limitation. Sounds more like "Lawyer" talk to me.

"LANDING
Normal landings are made power off with any flap setting. Slips are
prohibited in full flap approaches because of a downward pitch
encountered under certain combinations of airspeed and sideslip angle."
---------------------------------------------------------------------

I wear my "Slips with Flaps" T-Shirt proudly!

Bob Moore
12 years instructing in Skyhawks

--
Scott
http://corbenflyer.tripod.com/
Gotta Fly or Gonna Die
Building RV-4 (Super Slow Build Version)