I love eating those chocolate-coated marshmallow treats, also called chocolate teacakes. They combine the soft, fluffy texture of marshmallows, and the sweetness of the chocolate which accentuates the muted flavor of the mallow.
Back in the 1950s, the Royal Air Force included these chocolate teacakes into their ration packs. Everybody loved it. And they made an interesting discovery about these teacakes: they expanded as the aircraft climbed higher altitudes. They noticed that at 15,000 feet, the marshmallow started bursting out of the chocolate coating. Despite this, the flavor wasn't compromised. You basically got more out of the treat than when you started.
One incident, however, burst everybody's bubble, no pun intended. While on a flight, a captain and a student pilot unwrapped one of these teacakes and left it on the instrument panels. Then, the captain pulled an emergency depressurizing switch, which caused the teacakes to explode. The chocolate splattered on the windshield, the control panel, and the pilots' uniforms.
Needless to say, the RAF banned marshmallows from being brought into any aircraft ever again.
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