Magnesium metal will burn very violently once it gets going. Among the biggest trouble I got into in high school was when my chem lab partner and I decided it would be entertaining to burn a small piece of magnesium metal. It was rather spectacular, and indeed entertaining. Well worth the Very Stern Lecture.

Some aircraft historian will have to fill in the gaps in this story (what aircraft?), but back during the Korean War era, the USAF had a multi-engine piston-driven plane that was either a transport or a cargo aircraft -- not sure which, but the engine blocks were magnesium to save weight. One of the biggest brown-factor events that you could have was an engine fire, because once it got started, your day was going in a bad direction very fast. A friend's dad was pilot-in-command of a plane fresh out of maintenance. An engine caught fire on climb out. He ordered the rest of the crew to hit the silk and he tried to get back to the field. He did, but the landing was not pretty, and he suffered a nasty leg injury. No more combat rating for him, and he finished is USAF career flying transports, and later had a career as a commercial airline pilot. He was luck to survive that engine fire event.