When the Navy rekindled its interest in lighter-than-air in 1915, among the aircraft the sea service ordered were free balloons and kite balloons, the former used for training and the latter for observation and spotting naval gunfire. Eventually the Navy purchased 117 kite balloons and obtained seventeen more from allies overseas during World War I. Manning them was sometimes a dangerous proposition, with the crew having to climb ladders to reach the baskets suspended beneath the balloons as they floated above the ground or a ship. An easy target for enemy gunners, they never caught on as a reconnaissance platform, and were soon replaced by observation airplanes.