A worker has been critically injured in a Kemah Boardwalk rollercoaster accident. The man, in his late 50s, fell about 50-feet while working on the wooden rollercoaster known as the Boardwalk Bullet. The man, whose identity has not been released as of Tuesday evening, was performing maintenance work about halfway up the popular ride. He fell to a platform about halfway between the point at which he was working and the ground. Officials speculate the accident would have been fatal…