1.   Fuel can cause the most damage in a plane crash.

2.   Poor fuel caused the engines to fail on a giant military cargo plane that crashed in Siberia earlier this month, a Russian news agency reported Wednesday.

3.   Russian news reports suggested poor fuel may have caused engine failure during take off.

4.   Substandard fuel may have caused its engines to stall, investigators have said.

5.   The dumped fuel caused a small fire on a runway, but it was immediately put out by firefighters and caused only minor disruptions to other flights.