Transcript experience

Air crash investigation
causes and solutions
ULM Safety Day 16 March 2013
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AIR ACCIDENT INVESTIGATION UNIT
(Belgium)
• Part of the Federal Public Service – Mobility and
Transport.
• From the investigations, determine recommendations
for the improvement of flight safety.
• Does NOT determine liabilities nor blame.
• Independent from
DGTA / DGLV.
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NEW EU996/2010, Regulation on Air
accident investigation
• Obligation to investigate all accidents and
serious incidents with aircraft EXCEPT Annex II
aircraft (= ULM, Historic aircraft, paramotors).
• We do not investigate all ULM accidents, only
those for which we (arbitrary) think safety
recommendations can be made.
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NEW WEBSITE: www.mobilit.belgium.be
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ULM AND RESPONSIBILITY
• “Certified” aviation involves (a lot of) formal State
requirements for Standards, Quality Control,
verifications, testing, etc.., throughout the whole
aviation chain, from the designer to the end user.
• “ULM” means, in general terms, that each
element of the chain is (more) free from formal
constraints, but remains responsible for its
actions.
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THERE ARE LESS SAFEGUARDS IN
PLACE IN THE ULM SYSTEM,
AND THE AVIATION CHAIN IS
CONSTITUTED BY HUMANS
(GENERATORS OF HUMAN
ERRORS).
maintenance
assembly
design
THEREFORE THE ULM END-USER
NEEDS TO COPE WITH MORE
ANOMALIES GENERATED EARLIER
IN THE CHAIN TO ENSURE HIS OWN
SAFETY AND OF HIS
PASSENGER.
.
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Experience
feedback
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ULM AND SAFETY
Thanks to the safety awareness of ULM users, and
overall good quality of modern ULM airplanes,
• ULM and “Certified General Aviation (CGA)”
achieve more or less the same level of safety.
• Current fatality rate in Belgium is 5 deads /year
for both CGA and ULM and fatal accident causes
are identical.
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DESIGN
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STORM 280GS
After preflight (including
the draining of the fuel
filter), the pilots takes off,
and performs a series of
touch and goes for 30min.
During climb at 400ft agl,
the engine loses power,
the pilot selects a field
(45° from the axis) and
makes an emergency
landing. (EBCF)
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The inspection of the carburettor
reveals that the main nozzle is
clogged by a grain.
The design of the fuel filter
(originally maritime) is such that
the seal may be positionned off
center and allow contaminants
to pass through.
The carburettors have no “last
chance” screen filters.
However, the fuel filter bowl was
heavily contaminated. There was
no maintenance programme.
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MANUFACTURING
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Rainbow CHEETAH
The airplane takes off with
an instructor and a
passenger for an initiation
flight. In downwind, the
windscreen suddenly breaks
off.
The drag created by the
opened windscreen is very
important.
The pilot is forced to land
the airplane in a reed field.
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The windscreen is made of one
sheet of polycarbonate, bent to
shape and attached to the
structure with rivet nuts. Contact
between the structure and the
windscreen is protected by a
rubber seal.
During ULM assembly, the rubber
seal was omitted, and replaced by
a silicon joint, giving no vibration
dampening protection.
Cracks initiated in the windscreen
by vibration, evolved, and caused
the windscreen to fail.
Nevertheless, cracks in the
window were visible long before
the windscreen failed.
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MAINTENANCE
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Photo by William Larkins
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RANS Coyote (Rotax 582)
The airplane took off from
Ursel airfield. After a
while, the engine
coughed, and stopped.
The pilot made a perfect
emergency landing,
without engine.
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The engine stopped because the
fuel pump stopped.
The fuel pump is activated
pneumatically via an impulse line
leading from the nipple on the
crankcase to the fuel pump. The
tube cracked and failed.
The owner had replaced all fuel
lines 3 years before, except this
one, which was 5 years old when
it failed (the tube was brittle and
became opaque and black,
instead of transparent green).
The material used was polyurethane. All lines showed
evidence of ageing (cracks,
color,..)
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HM293 Pou du Ciel
It was the first flight after
repairs made on the NLG.
The landing on the MLG was
smooth. When the nose
wheel touched the ground,
the whole NLG fork
assembly separated.
The airplane tilted after a
short landing run.
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The pilot-owner intended to
manufacture a new NLG leg
out of 25CD4S steel.
He went to a reputable
retailer, and got a bar of
Stub Steel, advertised by the
shop keeper, as equivalent.
When checking the
specifications of both
material, we found out that
Stub Steel was not adequate
for the intended repair, in
particular the welding
capability.
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Owner’s input
• The owner is responsible to maintain the
airplane in safe condition.
• The owner chooses, decides,
communicates,….
• The owner may not be the only user, so
communication with the other users may
prove valuable to identify potential dangers.
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Owner’s input
• There are “operating manuals” and “operating manuals”.
We saw:
– Manufacturer’s manuals overly cautious:
An engine manufacturer describes Daily checks to be performed,
including verification of accessories mounting, condition of hoses,
rubber couplings for ageing, cables, filters, wiring, etc…
– Operating manual (although complying with the law) not showing
essential safety notes from the airplane’s manufacturer.
– Operating manual with extensive text, essentially advertising the
safety of the airplane.
Look for the right information; Operation manuals are no
advertisement folders; you need all factual and pertinent
information regarding your airplane.
• When the owner subcontracts the performance of tasks,
the Golden Rules are; “trust, but verify” and “Know your supplier”.
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Maintenance
• Maintenance checks are privileged moments for
an airplane; an experienced technician can detect
anomalies, (including “design” and
“manufacturing” anomalies) before they become
critical.
• Maintenance is not just changing engine oil and
tyres for the cheapest price (OK, it is expensive).
It’s an opportunity for advises and learning.
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PILOTS
If an earthquake suddenly opened a fissure in a runway that caused an
accident, investigators would find a way to blame it on pilot error.
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Pilot: the most complex piece of
technology in the ULM.
• Licences: ATPL, CPL, PPL, ULM Pilot
Authorization. Obtaining a pilot license is not
an achievement; it is only the beginning.
• Human Factors play a very important role in
accidents (Get-Home-itis, haste, mission-itis,
lack of knowledge, overconfidence, ...)
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Never trust a fuel gauge.
Airspeed, altitude, or brains;
you always need at least two.
Assumption is the mother of all fuck-ups
Good judgment
comes from
experience and
experience comes
from bad judgment.
Aviate, Navigate,
Communicate
Never let an aircraft
take you somewhere
your brain didn't get to
five minutes earlier
You don't know
what you don't
know.
Failing to prepare is
Preparing to fail
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You can only tie the record
for flying low.
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Airlony Skylane
During a training flight, with an
instructor and a student on
board, the airplane experienced
engine problems. The airplane
was flying at 2000 ft when the
engine stopped.
The instructor took over and
selected a location for an
emergency landing.
The approach and initial touch
down was uneventful. However,
when the nose wheel contacted
the ground, it sunk in the soft
ground, causing the airplane to
tip over.
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The engine stopped due to
fuel starvation.
The flight started with 2fingers height of fuel visible in
the window-indicator.
There are no quantity
markings on the window, and
the quantity of fuel remaining
is not proportional to the
indication.
Solution: calibration of the
“instrument”, to get an
information in the cockpit and
… use a (calibrated) dipstick !!!
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RANS Coyote
• The airplane was flying
back to its home base,
the Buzet airfield.
• The airplane was seen
turning sharp in final,
stalling, and entering a
spin.
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The pilot had started to fly in 2005,
bought his airplane in begin 2011.
Total flight experience: 500FH
Recent experience: from 29/7 till 21/10:
52FH
He flew a lot since he purchased his
own plane, without regular support of
an instructor (only for tail-dragger
conversion), and gained (reportedly) a
lot of self-confidence.
Wind: 040° 6kts
Field orientation: 155°/335°.
For reason of his own, the pilot was
eager to land immediately. The cross
wind was considered a nuisance.
When reaching base, in order to avoid
overshooting the runway axis, the pilot
made a sharp turn, at low speed using
too much rudder and ending in a
skidded turn, eventually stalling the RHAAIU(be)
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Instructors are there to help you!!!.
It is each pilot’s responsibility to
maintain and expand his piloting skills.
Instructor are there to help you, and
not only during basic training.
When flying alone, you may not realize
you’re making errors, and you are
therefore unable to correct them.
(You don’t know what you don’t know).
Flying with an instructor is not a waste
of money; it can save your life.
P.S. THIS IS NOT AN ULM INSTRUCTOR
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EXPERIENCE
Keep looking around. There's always something you've missed.
Learn from the mistakes of others.
You won't live long enough to make all of them by yourself.
EXPERIENCE IS NO LIFE INSURANCE.
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Auster V – 8 Aug 1950 - EBDT
• After a normal take-off, the airplane made a low pass above the
airfield and turned, climbing to 750ft agl. The engine was then
set to idle, the airplane still climbing. The airplane went into a
spin to the left.
After 3 spin turns, the airplane came almost in a horizontal line
of flight when it collided with the ground.
• The pilot and the passenger died
upon impact.
• The engine and flight
controls were inspected,
nothing abnormal was found.
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Capt vlw “Vicky” Ortmans, DFC
5 confirmed Victories;
2 damaged
Awarded DFC with effect from 18th September 1941.Has displayed great
keenness and courage in pressing home his attacks. He has destroyed at least 5
enemy aircraft and damaged a further 2
Shot down a German ace
without firing a shot.
Sabena pilot after the war.
www.vieillestiges.com
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QUESTIONS ?
An accident investigation is conducted by non-flying experts who need
six months to itemize all the mistakes made by a pilot in the sixty
seconds he had to do anything.
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