BRADFORD, Vt.—A hot air balloon designer and pilot who died after becoming entangled in gear underneath the basket of his balloon and then fell was known for his eccentricity and prowess in the industry. Brian Boland died Thursday after taking off with his balloon, which was carrying four passengers, from the private Post Mills Airport in the Vermont town of Thetford. Some time later, the balloon touched down in a field and one passenger fell out, but was unhurt. At that point, Boland, 72, became entangled in gear affixed to the balloon as it re-ascended. Police said he eventually “fell to the ground from a height” into a Vermont field and was later pronounced dead. After the pilot’s death, three other passengers remained in the balloon until it caught in a grove of trees about 1.5 miles north in Piermont, New Hampshire, where they escaped without injury. Mick Murphy, a …