Solar Impulse grounded for repairs

The sun-powered Solar Impulse 2 aircraft has been grounded in Hawaii, its crew said Saturday, after a grueling five-day, fuel-less flight across the Pacific Ocean overheated its batteries. The airplane took 118 hours to cross from Japan to Hawaii in the most perilous leg of its goal to circumnavigate the globe without a drop of fuel. The flight last week saw Swiss pilot Andre Borschberg smash a record for the longest solo plane flight. But the historic journey also took its toll on the aircraft's batteries, grounding it for repairs until at least August.
Too much insulation caused the plane's battery temperature to spike on the first day of the flight and there was no way to cool it after Solar Impulse was off the ground, the aircraft's team said.