Page 17 - Forum-2021-JanToMarch

accident. The examination after the accident malities in the helicopter until it collided with
revealed that the G switches that should ac- trees. It is somewhat likely that during the
tivate with impact from the front, left, above, time from when the helicopter turned right
and rear were stuck because the bulb-shaped above the mountains until when the captain’s
parts inside the ELT were rigidly fixed. right upper arm moved, at least there was
Because the ELT is an important piece of nothing wrong with the captain’s condition
equipment whose activation or nonactivation like loss of consciousness.
when an accident occurs can affect human Voices were not recorded after a rescuer
survival, inspection of items established said, “Right rear clear” until the helicopter
by the manufacturer must be carried out collided with trees. From this fact, it is some-
and certainly within the time period set by what likely that all members on board had
the manufacturer. Therefore, the contents not responded to the approaching danger.
contained in the manufacturer’s maintenance However, there is a possibility that the exten-
manual, including that pertaining to function- sion microphone of the video camera might
al inspection of G switches, must be clearly have come off the helmet, but this could not
stated in the ELT system maintenance manual be specified.
of the certified workplace, and the person who It is certain that the captain was under
conducts an inspection or maintenance must treatment for particular diseases, and he was
leave records of that inspection or mainte- taking the prescribed medicines. However,
nance. Even when a G switch satisfies techni- it could not be clarified whether the captain
cal requirements at the time of its manufac- was subject to influence of those previous
ture, it may deviate from those requirements diseases, which would hinder the perfor-
by becoming stuck or degraded with the mance of aviation duties or not, and whether
passage of time. Therefore, it is important to the captain took those prescribed medicines
make periodic inspections of ELT G switches during the flight and he was affected by those
mandatory. medicines or not.
The JTSB recognizes this as an important Regarding the helicopter’s not taking avoid-
issue because there are many accidents in ance maneuver, it is somewhat likely that the
which the ELT signal was not transmitted due captain could not recognize the dangerous
to the problems with the ELT and installa- situation and did not take any avoidance
tion and operation methods of the antenna, maneuver because he was in a state where the
and ELT problems hinder early detection of arousal level was lowered with microsleep,
survivors, and so on, because of fatigue and time differ-
ence. However, it was not possible to clarify
Lesson 8: The ELT is important for saving lives. whether he actually fell into such a state.
The captain should keep watch so as not to
Flight Recorder collide with other objects. If, for some reason,
For aircraft that are required to fly within he could not keep watch, it is highly probable
that it was necessary for him to have instruct-
small safety margins in activities involving ed the mechanic to temporarily keep watch
lifesaving and similar operations, the instal- for him.
lation and utilization of a flight recorder can If the mechanic did not question the cap-
prove useful in better understanding the char- tain about the flight route and the altitude,
acteristics and flight operations by regularly it is somewhat likely that his attention was
analyzing and evaluating the flight conditions focused on the instruments and the log pa-
in ordinary flight operations. If an incident or pers, and therefore he did not keep sufficient
an accident occurs, it will contribute signifi- outside watch; however, this could not be
cantly to precisely identifying its causes and specified.
developing recurrence prevention measures. If the rescuers in the cabin did not question
Accordingly, equipping such helicopter with the captain about the flight route and the al-
flight recorders is considered a high priority, titude, it is somewhat likely that they thought
and it is desired to study for its realization and that the highly experienced captain and the
promotion with the cooperation of relevant mechanic were grasping the outside situation
parties.
and keeping forward watch. Or perhaps that
they got used to low-altitude flight so much
Lesson 9: A flight recorder is important for acci- that their sensitivity to the danger became
dent investigation.
lower due to rescue mission and training;
however, this could not be specified.
Not Taking Avoidance Maneuver It is important for conducting safe helicop-
It is somewhat likely that there were no abnor- ter operations that all crewmembers display
January-March 2021 ISASI Forum • 17