by Ruth Banks

Accident investigators say a missing rivet head may have caused
a plane crash that killed five people in Farnborough in March
2008.

An official report into the accident says the missing component could have caused an inadvertent engine shut-down in the private jet.

The eight-seater Cessna Citation 500 burst into flames after
crashing just minutes after it took off from Biggin Hill airport on
a flight to France.

The pilots had decided to return to the airport, after reporting
engine vibration. Minutes later, they reported a ‘major power
problem’, and crashed into the side of a house.

Everyone on board was killed, including former motorsport
champion David Leslie, and Richard Lloyd, a racing team chief.

The report from the Air Accidents Investigation Branch found
that the "rivet head securing the left engine fuel cut-off lever
had become detached at some time prior to impact", which could have
caused the lever to be moved inadvertently into the fuel cut-off
position, causing an engine shut-down.

It added: "If the right engine had previously been shut down as
a result of the vibration, the aircraft would then have been left
with neither engine running."

Audio: David Learmount, editor at flight international and flight global.com

The investigators said a single engine relight could have
produced enough thrust to prevent impact, but there was evidence
that "one engine had not completed its start sequence before an
attempt was made to start the other. The effect of doing this would
have been to delay the start of both engines.

"Had the pilots been using the manufacturer’s checklist it is
possible that they misinterpreted the requirement to only start one
engine at a time or did not realise the significance of the need to
do so.

"A sense of urgency due to the proximity of the ground or
confusion over the problems they were dealing with might equally
have led to a deliberate attempt to start the second engine before
the first engine had reached idle speed."

The report complained that the "investigation was short of
critical information which could have provided further insight and
a clearer understanding of the factors leading to the loss of the
aircraft" by the lack of a black box flight data recorder.

Planes of this size are not required to carry them, but
proposals have been made to make them compulsory.