Hey Bob!
I am shocked and saddened by Cliff and Bettys accident at Oshkosh. This
should not
have happened to a pair who had been so helpful and friendly to others in
the flying
community.
It seems that there is some misunderstanding how a "cross controlled"
situation can
occur.
The classic cross controlled scenario is when the pilot overshoots the
base to final turn being
blown downwind using heavy ailerons and rudder to correct the overshoot up
to the point the plane is headed back to the runway and then the pilot uses
rapid opposite aileron to level the wings. The downgoing aileron on the
upwind side is asked to generate a lot more lift when the airspeed is very
slow, causing the upwind wing to stall precipitating a low altitude spin.
I was taught on the Europa to never use the bottom rudder on the turn from
base to final and just make the turn with ailerons. If you hit the bottom
rudder, you are slowing the inside wing more than the outside wing. It is
permissible to use the top rudder in the turn as this accelerates the inside
wing (which is what you do in a slip). So one can cause a stall by using
bottom rudder and not be cross controlled. I was taught that as long as you
use top rudder only (or no rudder at all) on the base to final turn, the
inside wing cannot stall first. Once lined up on final, I then start using
the rudder to maintain directional allignment with the runway. If I can't
make the turn just using the ailerons, I have screwed up and will do a go
around! The whole idea is that as long as
the aircraft stays coordinated, the wing will only stall straight ahead,
still not a good thing, but
possibly recoverable where a spin entry is not.
Glenn
>From: "Bob Jacobsen" <jacobsenra@hotmail.com>
>Reply-To: europa-list@matronics.com
>To: europa-list@matronics.com
>Subject: Europa-List: Europa Oshkosh Accident
>Date: Fri, 28 Jul 2006 07:55:00 -0700
>
>
>I have additional information on Cliff & Betty's Oshkosh accident. First
>is the NTSB's preliminay report - this can also be found on the NTSB
>website.
>
>Also the NTSB has spoken with Mike and a pilot we know who was an
>eyewitness. Additionally I test flew Cliff's plane for him, knew him well
>and knew what kind of pilot he was. My hope is this information will
>prevent another accident of this type.
>
>First the NTSB Report:
>
>NTSB Identification: CHI06FA196
>14 CFR Part 91: General Aviation
>Accident occurred Sunday, July 23, 2006 in Oshkosh, WI
>Aircraft: Shaw Europa XS, registration: N229WC
>Injuries: 2 Fatal.
>
>This is preliminary information, subject to change, and may contain errors.
>Any errors in this report will be corrected when the final report has been
>completed.
>
>On July 23, 2006, at 0845 central dylight time, a Shaw Europa XS, N229WC,
>collided with the runway following a loss of control while on final
>approach to runway 27 (6,178 feet by 150 feet, dry asphalt) at the Wittman
>Regional Airport (OSH), Oshkosh, Wisconsin. The private pilot and passenger
>were fatally injured. The airplane was destroyed. The 14 Code of Federal
>Regulations Part 91 personal flight was operating in visual meteorological
>conditions without a flight plan. The flight originated from the Portage
>Municipal Airport (C47), Portage, Wisconsin, at approximately 0815.
>
>The airplane was landing at OSH for the EAA AirVenture fly-in. Witness
>reported seeing the airplane "low and slow" on downwind to runway 27. One
>witness, a certified flight instructor, stated the airplane remained slow
>as it overshot final approach. The witnesses reported seeing the airplane
>stall on final approach. The airplane impacted the runway on the displaced
>threshold.
>
>Now information about Cliff's plane.
>
>I test flew the plane for the first time on 6/29/03 - Flight lasted about a
>half hour. I did some slow flight to get airspeed readings but did not
>fully stall the airplane. I felt that it would drop a wing - so I was very
>careful to keep everything centered. About a week later John Hurst was
>flying the plane with Cliff to try to iron out an engine problem. They
>stalled the plane and it flipped inverted instantly. We added some stall
>strips and got it's behavior a bit better - but it was a always a nasty
>stalling airplane.
>
>final. I am sure he pulled a hard turn to final while slow. I can also
>guess he was a bit cross controlled and the plane stalled. snapped inverted
>and went into a spin. I am told the plane impacted nose down and inverted.
> I am also told it had spun "a couple of times".
>
>The Europa is a great design however it does have a very powerful and
>sensitive elevator (thats why is so fun). Additionally the rudder is
>powerful - but must be used correctly. Cross controlling and accelerated
>stalling any airplane is a problem, the Europa is even more so than some
>and probably easier to do with the powerful controls.
>
>
>Here is waht the FAA pilots flying handbook says about this:
>
>According to the FAA publication Airplane Flying Handbook, section on
>accelerated stalls and cross control stalls, ...Stalls which result from
>abrupt maneuvers tend to be more rapid, or severe, than the unaccelerated
>stalls, and because they occur at higher-than-normal airspeeds, they may be
>unexpected by an inexperienced pilot. Failure to take immediate steps
>toward recovery when an accelerated stall occurs may result in a complete
>loss of flight control, notably, power-on spins... a cross control
>stall...is most apt to occur during a poorly planned and executed
>base-to-final approach turn...the airplane often stalls with little
>warning. The nose may pitch down, the inside wing may suddenly drop and the
>airplane may continue to roll to an inverted position...It is imperative
>that this type of stall not occur during an actual approach to a landing
>since recovery may be impossible prior to ground contact due to the low
>altitude...."
>
>
>Bob Jacobsen
>
>
>http://www.matronics.com/Navigator?Europa-List
>http://wiki.matronics.com
>
>
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