In the week or so that has elapsed since the tragic loss of Cliff and Betty
Shaw in their Europa at Oshkosh, in addition to the many expressions of
grief and sympathy which we all share, there have been many postings on this
list regarding the handling characteristics of the aircraft and their
possible contribution to the crash. Some of the posts might be regarded as
scaremongering, and the Europa Club Committee feels it is appropriate to
examine the aspects that might have a bearing on flight safety so that we
all may learn something from the collective thoughts that have followed this
tragedy.
that the aircraft stalled on final approach and appeared to hit the ground
inverted. We do not wish to speculate as to the possibility of pilot
incapacitation or mechanical failure - this is properly left to the NTSB
investigation and their final report - but we have reviewed the design,
build and operation of Europa in the context of a stall/spin accident and
would like to share the following thoughts with the aim of helping others to
think in a way that may help to prevent future accidents.
The handling of the Europa in flight is general regarded as being superior
to many other light aircraft, including certified GA aircraft, and we would
not wish people to gain the impression that its response near and at the
stall was particularly dangerous. Many aircraft will drop a wing at the
stall, especially if the slip ball is not in the centre, and some homebuilt
aircraft may exaggerate this tendency if there is a significant inaccuracy
in build.
When referring to measures used in preventing accidents, airline people use
the analogy of 'layers'. All these 'layers' are like slices of cheese with
holes in them. The potential accident is trying to find its way through and
occasionally it finds a hole in a layer of cheese. Provided the layers of
cheese have few enough holes and there are enough layers and the holes don't
line up, the potential accident should not become a reality. Layers can be
anything from pilot training and aircraft design right through engineering
practices and construction skills to pilot skill and coping with workload.
This helps us move away from scape-goating and looking at ways of either
adding extra layers or reducing the holes in layers. In the present
situation the following layers come to mind:
Design - We believe this was both professional and sound. We were lucky to
have someone as knowledgeable as Don Dykins. If there had been a fundamental
design problem it would have been identified before now.
Construction - Without doubt there are bigger differences in construction of
Classics rather than XS Europas. In both cases accurately setting up
identical angles of incidence and identical flap positions between wings is
every bit as important as aiming for the specified numbers. To ensure the
washout is at least as much as that intended aileron droop should be
avoided. If necessary both ailerons should be a little raised in straight
and level flight. This is generally easier to arrange as the balance weight
clearances from the top wing surface can be a problem if there is any droop.
Pilot training - Whilst monowheels need specific skills for take-off and
landing, stalls and the handling skills required should be no more demanding
than any other aircraft type.
Test Flying - Where possible this should be done by someone with significant
Europa experience on many different aircraft. Also to avoid conflict of
interest at least some test flying should be done by someone with experience
who is not the owner. Where any unusual stall handling is observed this
should be addressed before the aircraft receives its permit. Whether stalls
trips and/or stall warners are used there should be no problem identifying
the impending stall at least 5 to 7kts above the stall. As parts can move
slightly (for instance due to wear) any changes of stall handling during
annual flight tests should be addressed without delay.
Pilot skills - Practice identifying the approaching stall and carrying out
the stall recovery with minimum height loss regularly. Be sure to include
stalls with gear and flap down as well as clean and practice identifying
stalls in the turn. Obviously this should be done at a safe height. Always
fly the aircraft in balanced flight (ie not cross controlled) unless you
have significant excess speed above the stall. When flying in a high
workload environment keep to as standard a pattern as possible. Outside
distractions such as many other aircraft at an airshow or landing at a
difficult strip or landing in bad weather must not prevent accurate control
of speed and flightpath. We know this has led to landing with gear retracted
in monowheels so stalling on base leg or on finals is just as possible in
these situations. As they say Aviate - Navigate - Communicate. Another adage
we use in the airline world is Plane - Path - People. These help you
prioritise your tasks. Do not feel pressurised to continue an approach if
things are not right.
Finally, whilst on the topic of adages, there are two more which come to
mind:
The superior pilot uses his superior knowledge to avoid using his superior
skill.
There are old pilots and bold pilots but no old bold pilots.
We hope this very sad event has helped the rest of us take on board how
suddenly things can change when we are least expecting it.
Fly safely
Mike Gregory
Europa Club Safety Officer
safety@europaclub.org.uk
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