On May 16 a rotor blade broke off a helicopter on the roof of Manhattan’s Pan Am Building after the copter’s landing gear failed, causing it to turn sideways. The blade killed four people and then plunged over the side, broke some windows and killed a woman on the ground.  

The helipad was reopened in February 1977, just three months before the accident. The National Transportation Safety Board determined that the accident was caused by “metal fatigue”. The Pan Am helipad was shut down following the accident and has not reopened.