The following was
posted on the Mistral-Engines web site. It is another data point on the very
harsh environment of the exhaust system, particularly in the NA
engines.
Giff
Marr
LIV-P/Mistral
70%
More fear than
harm
07 June
2008
On Tuesday morning, 3rd of June, our
test pilot, Mr Stephen Roth, took off for a first one-hour flight that went
flawlessly. He landed at Palatka’s Kay Larkin Field Airport,Florida, to refuel. Pre-take-off checks
were normal and so was take-off. On initial climb, however, the engine
started to lose power while still running perfectly smoothly. The pilot
performed a 180° turn to return to the airport. The loss of power increased,
and the pilot was unable to maintain altitude.
He landed the plane under control and
at minimal airspeed in a wooded area to avoid buildings and houses. The
wings were sheared off, one of them staying in a tree, and the fuselage fell
sideways onto the ground. Coming to his rescue, two courageous citizens
helped him out of the cockpit conscious and unharmed. There was no
post-crash fire, only smoke from engine coolant leaking onto the heat
exhaust.
MISTRAL Engines is extremely happy and
most relieved to announce that Stephen Roth suffers only from minor cuts and
bruises. After a thorough check in the hospital, which proved to be short,
he was released and able to go back to the site to contribute to the
beginning FAA enquiry.
MISTRAL Engines immediately dispatched
to the site Mr Gordon Anderson, its Chief Operating Officer. On Thursday 5th
of June, Mr Anderson, Mr Roth and the FAA investigator inspected the plane’s
wreckage as well as the whole engine data log which was retrieved entirely
uncompromised from MISTRAL’s proprietary Digital Engine Management (DEM)
system.
It was quickly evident that all engine
parameters were normal from the moment of take-off to the moment of the
accident, with the exception of abnormally low propeller RPM. The cause of
the power loss was subsequently found in the failure of the internals of the
exhaust system’s muffler, obstructing the free flow of exhaust gases from
the engine.
This particular muffler was a temporary
and experimental solution developed and manufactured by a third party, which
was planned to be replaced this coming summer by a certifiable unit,
developed in-house. The FAA, acting on behalf of the NTSB1, retained the muffler in order to conduct flow
tests.
A preliminary report was produced by
MISTRAL Engines. It will be posted on this website shortly. A final company
report will be issued after further analysis of the engine is conducted at
MISTRAL’s facility in Geneva.
After its pilot emerging unscarred from
this mishap, MISTRAL is extremely relieved that its technology is proven
uninvolved in the cause of the accident and that, through the innovative
data logging capability of its DEM system, it was able to significantly
contribute to a prompt and thorough determination of the
causes.
MISTRAL Engines is in the process of
acquiring a new airframe to resume its flight testing programme as soon as
possible, and the type certification programme of its G-300 engine model
continues unhindered.
1 NTSB :
National Transportation Safety Board