According to the National Transportation Safety Board (NTSB), the probable cause of a midair collision between two emergency medical service (EMS) helicopters last year was that both pilots failed to see and avoid the other helicopter on approach to the helipad. Contributing to the accident were the failure of one of the pilots to follow arrival and noise abatement guidelines and the failure of the other pilot to follow communications guidelines.
On June 29, 2008, two Bell 407 EMS helicopters, operated by Air Methods Corporation and by
Classic Helicopter Services, collided in midair while
approaching the Flagstaff Medical Center (FMC) helipad in
Flagstaff, Arizona. All 7 persons aboard the two
helicopters were killed and both helicopters were destroyed.
“This accident highlights the importance of adhering to the
regulations and guidelines that are in place,” said Acting
Chairman Mark V. Rosenker. “Had these pilots been more
attentive and aware of their surroundings, and if
communications would have been enhanced, this accident could
have been prevented.”
In its report today, the Board noted that both EMS
helicopters were on approach to the Flagstaff Medical Center
(FMC) helipad to drop off patients. During the flights,
both pilots had established two-way communications with
their communications centers and provided position reports.
The FMC communications center coordinator advised the Air
Methods pilot that there would be another helicopter
dropping off a patient at FMC. The FMC coordinator also
advised Classic communication center that Air Methods would
be landing at FMC, but the Classic communication center did
not inform the Classic pilot nor was it required to do so.
However, the Board stated that if Classic's pilot had
contacted the FMC communications center, as required, the
FMC transportation coordinator likely would have told him
directly that another aircraft was expected at the helipad.
If the pilot had known to expect another aircraft in the
area, he would have been more likely to look for the other
aircraft, the report stated.
As documented in the report, Air Methods did not follow the
noise abatement guidelines, to approach the helipad from a
more easterly direction. Classic approached the helipad from
the northeast, and it is likely that the pilot would have
been visually scanning the typical flight path that other
aircraft approaching the medical center would have used.
Thus, if the Air Methods helicopter had approached from a
more typical direction, the pilot of the Classic helicopter
may have been more likely to see and avoid it.
Neither helicopter was equipped with a traffic collision
avoidance system, nor was such a system required. Had such a
system been on board, the Board noted, it likely would have
alerted the pilots to the traffic conflict so they could
take evasive action before the collision. However, according
to Federal regulations, ultimately the pilots are
responsible for maintaining vigilance and to be on alert and
avoid other aircraft at all times.
The Board’s report, including the probable cause, is
available on the NTSB’s Web site athttp://www.ntsb.gov/ntsb/brief.asp?ev_id=20080715X01051&key=1.