When the injured need to reach a hospital after a major earthquake, helicopters could be the only option.
With so many people in need, loading patients must happen quickly.
"We're trying to get in and out, in and out," said Maj. Patrick Johnson of the Washington Army National Guard, explaining an exercise on Vashon Island Wednesday where volunteers from the Community Emergency Response Team learned how to "hot load" a patient onto a military helicopter.
That means taking a patient to the helicopter while the blades are still moving.
It's a loud and dusty experience.
And it's a skill that Vashon community members now have after drilling with the National Guard as part of the regional Cascadia Rising exercise.
Since they never know what kind of helicopter might arrive to take injured people off the island, the skills could be valuable.
On Vashon, disaster preparedness is taken seriously.
If the ferries can't run, the island will be cut off.
"On the mainland you should be prepared for three days. Here we say be prepared for two weeks to be on your own," said Jim Lilje, a Vashon CERT leader.
That's why volunteers with the Vashon-Maury Island Radio Club built a communications trailer with capabilities that range from Morse code to sending email by ham radio.
"We try to be self-sufficient as much as we can," said John Galus of the radio club.
Since landing on the beach Monday and building a camp, the National Guard has been prominent in the Cascadia Rising drill on Vashon.
But it is the resilience of islanders that will be most critical, if the worst happens.