After two months of darkness, the villages of Western Alaska are desperate for fresh supplies. Jim attempts a risky landing on a frozen river and Luke has problems getting his plane in the air. A pilot flies to the Russian border to deliver vaccines.

The Iditarod dog sled race brings big business to Era Alaska. Ferno, Ayla and Ariel Tweto run with the reindeer in Anchorage. A pilot battles malfunctioning trim control over the frozen Norton Sound and a tsunami warning threatens the entire West coast.

A late winter storm threatens to shut down Era Alaska's operations. Ben encounters dangerous icing conditions on his way to St. Michael. Lead pilot, Erik, resorts to drastic measures to get desperately needed medicine to a snowed in village.

A group of world-renowned rock climbers arrive in Unalakleet and Jim must fly them deep into the remote Brooks Range.

Jim searches for a group of missing mountain climbers lost somewhere in Alaska's Brooks Range.

Era Alaska provides aid to a village devastated by heavy flooding. Two pilots get lost in a sea of fog off the Russian coast while trying to deliver desperately needed ammunition. In Anchorage, Jim's prized Cessna 180 goes up in smoke.

Ponts' old skate crew arrives to build a skate park for local kids on Unk's newly paved roads. Ariel takes to the skies in a new plane with dangerous results and lead Pilot Erik Snuggerud battles heavy turbulence with a very special delivery.

Two pilots carry propane to a secluded fishing lodge; Luke wrestles with failing equipment over the tundra; Ponts challenges Ariel to execute a perfect landing.

Ariel looks for seagull eggs; Erik has a rough flight over a notorious runaway; Sarah takes her first flight in a 208.

Era digs deep to survive a brutal winter. Ariel joins in on a desperate search for her missing friend. Sarah Fraher attempts a difficult landing to aid a pilot stranded mid-runway. Ponts attempts an emergency medical drop over the isolated Kavik camp.

Alaska's harshest winter in years wreaks havoc on Era's fleet. Sarah Fraher's aircraft door opens mid-flight. Doug's brakes freeze on an icy runway while carrying explosive chemicals. Jim attempts a risky landing atop the frozen Anvik River.

The epic Iditarod dog sled race begins in Anchorage. Pilot Doug Stewart tests his limits while landing on a runway that is melting into the ocean. Pilot John Kapsner races to locate two snow-machiners that are lost overnight deep in the Alaskan Bush.

In Bethel, pilot Erik Snuggerud is plagued by mechanical issues. On Alaska's North Slope, pilots Doug Stewart and John Rende battle to keep their plane from careening off an icy runway. In Unalakleet, Ariel receives a surprise visitor.

In the skies above western Alaska, Ariel disappears from radio contact, putting emergency services on high alert. Over the remote village of Hooper Bay, pilot Erik Snuggerud battles to touch down on a dangerously narrow runway.

Jim makes an impossible landing in Unk. Pilot Sarah Fraher battles strong headwinds while attempting to deliver 2,000 pounds of fuel to the research station. Pilot Ben Pederson braves 50 mph winds to retrieve an elusive priest for Easter service.

Villagers in Wainright lose their water supply due to the Arctic cold. Solar flares leave Ponts and Ben in harm's way. In Unalakleet, a criminal is on the loose and the Tweto's are on edge.

Two pilots push their limits to land vital vaccines two miles from Russia on Alaska's most treacherous runway. In Unalakleet, Ariel Tweto takes to the skies once again and proves that she still has a lot to learn.

In the frigid Alaskan town of Unalakleet, the Tweto's and their family-run airline Era Alaska Aviation battle the arctic elements to transport supplies and passengers to some of the most non-accessible spots in North America.

Pilot Yuri Ivanoff trains in Bethel; Jim tries to do a river landing in Unalakleet.

Unseasonably warm weather sends Jim up to the Brooks Range to look for potential landing strips. Ferno and Ariel prepare an Eskimo feast for returning pilot John Ponts and the week ends with an icy plunge into the Unalakleet River.

In Bethel, construction crews race to finish ERA's newest hanger before the unforgiving winter snows arrive. But when Jim flies in to inspect the progress, he is far from happy. In Unalakleet, fierce crosswinds blow John Ponts' tiny 207 all over the sky.

Halloween in Alaska brings vicious crosswinds that wreak havoc on Era's small planes. Ariel hopes to learn the family business in Unk, but a power blackout tests her abilities when she takes over as station manager.

John Ponts fights heavy turbulence and angry passengers on a flight through the Nulato Hills. Jim and Ferno's leave the terminal in the hands of the pilots and Sarah's flight to rescue a villager lost in a storm turns into a battle for her own survival.

In a dangerous mission, pilot Doug Doherty flies along Russian airspace to transport volatile explosives to the island of St Lawrence. In Unk, Ben slams into a large bird mid-flight.

In the series finale, after 30 years of running Era Alaska, Jim Tweto sets his eye on a new path. Doug loses all avionics while flying over the North Slope. Ariel comes face to face with the FAA in the last step of getting her pilot's license.