62nd Airlift Wing Recalls Mount St. Helen’s Eruption on 40th Anniversary

  • Published
  • By Ms. Erin Lasley
  • Historian, 62nd Airlift Wing

McChord Field offers a spectacular view of Mount Rainier. The summer sun highlights the gorgeous peaks of the volcano and the winter dawn frames the mountain in different hues of red and gold. While we marvel at its beauty, many of us are aware of its potential threat. However, it was not Rainier which threatened McChord 40 years ago, but another volcano 70 miles southeast.

At 8:32 a.m. on May 18, 1980, Mount St. Helens erupted with a violence that blew more than 1,300 feet off its summit. The first serious indication that the volcano might be girding itself for an explosion was spotted on March 27, when a Portland Air National Guard pilot flying the area noticed the opening of a fissure with steam pouring from the vent. In the next few weeks, seismologists reported harmonic tremors, indicating molten rock moving up inside the mountain. Then, the north side of the volcano began bulging out until it had swollen several hundred feet.

The tremendous pressure caused Mount St. Helens to explode with a force estimated to be 400 times more powerful than the atomic bomb dropped on Hiroshima. The blast leveled more than 150 square miles of forest and sent a torrent of hot mud 30 feet high, roaring across Spirit Lake at the foot of the mountain and down the Toutle River to the Columbia River.

Immediately following the eruption, the Washington State Department of Emergency Services (DES) requested Air Force assistance for disaster relief operations in the area surrounding the volcano. A number of Military Airlift Command (MAC) aerospace rescue and recovery units rushed in to recue scores of people trapped by hot volcanic ash and mud flows. While helicopters continued to search for other survivors and the bodies of victims, other MAC units provided overhead communications links between the helicopters and disaster relief agencies.

A C-141 Starlifter and crew from the 63rd Military Airlift Wing at Norton Air Force Base, California, had stopped at McChord to refuel during a routine mission to Alaska. While the aircraft was at McChord, the McChord command post received a call from the Washington DES for communications assistance. The C-141 diverted to the disaster area and flew above the site for almost three hours, relaying communications between the Washington DES and other aircraft involved in the operations.

A C-130 Hercules crew from the 36th Tactical Airlift Squadron at McChord also flew overhead communications orbits, together with a C-130 from the 303rd Aerospace Rescue and Recovery Squadron, an Air Force Reserve unit from March Air Force Base, California. The 62 MAW C-130 had been scheduled to airdrop Army Rangers near Mount Rainier and then into the Yakima Firing Center when it was diverted and sent into a communications orbit around the volcano.

In addition to devastating areas around the volcano, billowing plumes of ash filled the skies over southeastern Washington following the eruption. A cloud of volcanic dust over ten miles high began drifting eastward.

The command post at McChord received updated weather forecasts every six hours to determine the pattern of wind directions in the event of a large-scale eruption from Mount St. Helens. Because volcanic ash could ruin aircraft engines, it would be necessary to evacuate the wing’s aircraft if the ash reached McChord. Facilities only existed to house 11 of the aircraft permanently assigned. Fortunately, for McChord, the wind carried the enormous ash clouds to the northeast, allowing the base to escape the fallout enveloping other parts of the state immediately following the eruption.

Fairchild Air Force Base was not as lucky. On the morning of May 18, Fairchild planned to hold an open house and air show for the public, but cancelled the show when winds carried the ash Mount St. Helens spewed from its top toward the base. Many transient airshow aircraft were able to escape, but many, including an F-106 from McChord, were forced to hunker down at Fairchild. By the morning of May 19, the base was blanketed with over an inch of ash.

Back at McChord, all flights, save for those involved in search and rescue, were grounded due to the abrasive properties of the fine, gritty ash that could cause major damage to engines and cockpit windows. By May 22, the skies had cleared enough for an aircraft with Great Britain’s Prince Philip, the duke of Edinburg, aboard to land at McChord. He was en route to San Francisco from Canada when his aircraft diverted to McChord to refuel because of the ash.

When the second major eruption occurred on May 25, McChord swung back into action, supporting search and rescue operations and began implementation of aircraft evacuation when it became apparent volcanic ash was headed for McChord and the western coastline. In barely over four hours, McChord launched 26 aircraft to escape the dangerous ash and resumed operations from Travis Air Force Base, California, and Elmendorf Air Force Base, Alaska.

Throughout the summer of 1981, Mount St. Helens would continue to sporadically erupt and disrupt air travel and military operations because of volcanic ash. Unlike Fairchild, McChord only received light dustings of ash and were able to quickly clean up the deposits.

While McChord was fortunate to escape the wrath of Mount St. Helens, the volcano wreaked horrifying damage across Washington. The eruption directly killed 57 people and hundreds of thousands of animals, leveled hundreds of square miles of forest and farmland, and caused over $1 billion in damage. The U.S. Geological Survey estimated Mount St. Helens discharged 24 megatons of thermal energy, equivalent to 1600 times the size of the atomic bomb dropped on Hiroshima.