Relatório do Acidente ocorrido no Incêndio Florestal de Yarnel Hill

Analysis
There is a gap of over 30 minutes in the information available for the Granite Mountain IHC.
From 1604 until 1637, the Team cannot verify any communications from the crew, and we have
almost no direct information from them. We cannot fully know how they made their decisions
prior to their entrapment and fire shelter deployment around 1642. No crewmembers from the
deployment site survived to tell why the crew took the
actions they took.
However, for the sake of creating a learning tool, the
Team has developed an understanding of what the
Granite Mountain IHC likely knew and saw during this
period. The Team based this on information from
various sources, including accounts from others on the
fire, information from dispatch logs, photographs,
radio conversations, and fire modeling. The Team
conducted site visits to retrace events, drew from their
understanding of wildland fire operations and culture,
and considered the perspectives and experience of
SMEs.
This Analysis helps reconstruct the context in which
the crew was operating. The Team attempts to avoid
oversimplifying and judging the crew’s actions in
hindsight. Instead, we aim to understand how the
Granite Mountain IHC and others on the fire made
sense of their situation at the times when they took
the critical actions.
Foresight vs. Hindsight
After an accident, investigators
learn information that participants
may not have known at the time,
such as the actual rate and
direction of fire spread, the
outcomes of various events, and
other relevant details. This
information can be very clear in
“hindsight,” but it may not have
been so clear at the time.
To understand key actions more
fully, it is necessary to set aside
the information that we only
know in hindsight, and try to
understand what they knew in
“foresight.” The purpose is to try
to put ourselves in their shoes
and minimize “hindsight bias.”
Three key actions this section focuses on are A) The
Granite Mountain IHC’s movement to the southeast
along the two-track road sometime after 1604; B) Their descent from the two-track road
sometime around 1620; and C) Their shelter deployment around 1642.
This is the Team’s interpretation and reconstruction of these moments. The Team may be
assuming a more deliberative thought process than what the Granite Mountain IHC actually
used at the time. Nobody will ever know how the crew actually saw their situation, the options
they considered, or what motivated their actions. The purpose of this section is to provide a
tool that others can use for learning and prevention.
Yarnell Hill Fire Serious Accident Investigation 33