The NTSB has determined in the case of two EMS helicopters that collided near Flagstaff Medical Center last June, killing all seven persons aboard, that had the pilots "been more attentive and aware" and communications more thorough the accident could have been prevented. According to the NTSB, the actions of both pilots contributed to the accident that destroyed the two Bell 407 EMS helicopters while on approach to the helipad. En route, the pilots of the aircraft were in communication with their communications centers and both provided position reports. The communications center at Flagstaff Medical Center advised the first pilot that the other helicopter would be dropping off a patient and advised the second pilot's communication center of the first aircraft's arrival. However, that communication center failed to relay the information to the second pilot (and was not required to do so, according to the NTSB). The second pilot then failed to contact communications at Flagstaff Medical Center, which was required, and so arrived on scene uninformed of the first aircraft's presence. Further, the first pilot flew a non-typical approach that was not in accord with noise abatement guidelines and would not have been expected by the second pilot. Neither aircraft had onboard a collision avoidance system.
The NTSB found that had a typical approach been flown by one of the aircraft, had either aircraft been equipped with a collision avoidance system (not required), and had required communications procedures been employed it is likely the accident could have been avoided.