​Runway Closure at Thun Field Forces Scramble for Local Operators

Facing a critical four-month shutdown starting July 27, tenants and flight schools at Pierce County Airport-Thun Field (KPLU) in South Hill, Washington, are rushing to relocate as the facility begins a $7.18 million federally funded project to replace its aging runway.

“[Runway 17-35] is reaching the end of its lifespan and needs to be reconstructed to remain operational,” said Trent Smith, airport manager with the Pierce County Planning and Public Works Department. “This project safeguards a critical county asset. By securing a new 20-to-30-year runway lifespan, this investment eliminates costly emergency repairs and preserves runway access for airport businesses, tenants, pilots, and emergency services.”

The closure was not a surprise to anyone at the airport, but that doesn’t mean the impact won’t be felt. For months businesses, tenants, and pilots have been wondering where they will go and what they will do during the temporary closure. 

Part of the challenge was that Pierce County, the airport sponsor, had discussed the project for several years. It would surface, then be put on the back burner when more pressing matters came up. Airport tenants began to doubt the project would happen in their lifetime.

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As part of the long-term planning the county discussed the need to replace the 3,651-foot-by-60-foot runway. The county told airport users that the runway’s length will remain the same, but it will be widened to 75 feet, and the airport hangar’s electrical infrastructure will be rehabilitated.

Additionally, the field drainage will be improved, new PAPI (precision approach path indicator) lighting will be installed, two taxiway connectors will be realigned and repaved, and the windsock, segmented circle, and wind tee will be relocated. The trees and brush that obstruct pilot sightlines and block the Automated Weather Observing System (AWOS) will also be removed. 

The construction is being funded by a $7.18 million FAA Airport Improvement Program (AIP) grant. On-site work will kick off with hangar electrical rehabilitation beginning July 24.

During the months of planning the county heard a great deal of concern about the impact a total runway shutdown would have on airport tenants, businesses, and flight schools. Some of them offered the following suggestions to mitigate the impact:

• Perform the work in the winter when there is less flyable weather. However, that idea was shot down immediately as it was noted that weather delays would stretch out the project and increase the cost.

• Perform the work in phases that would allow part of the runway to remain open or at night so that it could be open during the day. This also was rejected. “While we explored alternatives to minimize disruptions, a phased approach or night work is not feasible for this project,” Smith said in a statement to FLYING. “Due to the runway’s specific length requirements and strict budget constraints, the reconstruction must be completed in a single, non-phased timeline during daylight hours.” 

• A proposal to use the taxiway on the west side of the runway as a temporary one was nixed as too risky because it is in close proximity to the hangars.

The county website notes that “monthly fees for hangars and tie-downs remain in effect as these cover the exclusive use of the storage space, which remains accessible. Tenants are encouraged to review their individual lease for any exceptions.”

Hangar tenants, some paying $373 per month for one with electricity, were told they would need to continue to make the payments while the runway is closed or risk losing their space. They were also advised to expect an increase in hangar rent in 2027. 

In airport advisory meetings a few business owners who depend on fly-in traffic asked if they would still have to pay rent during the closure. When the answer was yes, it sent a murmur of displeasure through the audience.

“While the runway will be closed to fixed-wing operations during construction, the airport grounds, hangars, and facilities will remain accessible, allowing businesses to continue operating,” Smith said. “Lease agreements remain in effect, and Pierce County does not anticipate offering rent reductions or adjustments during this period.”

Spencer Aircraft, one of the larger businesses at the airport with a pilot supply store, maintenance, and avionics department, has spent several months adjusting logistics to prepare for the shutdown.

“Avionics is working out of Auburn [Municipal Airport/S50], and Spencer Aircraft will still be working from our location,” said Duane Wetherbee, vice president of Spencer Aircraft. “We will also have a few planes working in our hangar that are staying on the field.”

Some tenants who requested anonymity stated the extended closure would kill their businesses, some of which have not completely recovered from the COVID-19 pandemic that choked supply chains and made it difficult to get parts for aircraft repair. 

Field maintenance providers have been looking for temporary locations from which to operate.

Flight Schools

KPLU is one of the busiest training airports in the Seattle area, with no fewer than three robust flight schools—Safety in Motion (the sister company to Spencer Aircraft), Spanaflight, the oldest flight school in Pierce County, and Clover Park Technical College.

As of Friday morning, all three were preparing to temporarily relocate to Olympia Regional Airport (KOLM), 27 nm to the southwest. The airport is a towered Class D facility with a VOR on the field.

Spanaflight and Safety in Motion have operated satellite schools out of KOLM for several years. During the work Spanaflight will also operate a temporary facility out of Auburn Municipal, a non-towered airport some 14 nm to the north of KPLU.

Clover Park Technical College (CPTC), which has its aviation campus on KPLU’s southeast corner, is also temporarily moving to KOLM. CPTC has been at KPLU since 2000 when a purpose-built facility known as the South Hill campus was constructed to house the flight training and aviation maintenance programs. The main campus for the school is in Lakewood, Washington. CPTC traces its roots back to 1942 when it was established to train people to support the war effort.

Claire Korschinowski, CPTC dean of instruction, aviation and advanced manufacturing, said the relocation of the flight program to KOLM is temporary.

“Training will be done in our fleet with our employees,” Korschinowski said. “We are working under a Part 141 certificate, and the FAA gave us a letter of understanding to allow us to operate in the temporary location. The FAA recognizes this is a set of circumstances that we cannot control, and we want to remain providing service to the community.”

The CPTC program has 47 students enrolled at this time. Usually there are as many as 60, but some students chose not to return for summer quarter because of the impending closure. Many of them are using their Veterans Administration benefits to pay for training.

 Korschinowski said it has been careful about keeping the students, as well as VA administrators, informed.

“The students will still do their ground school on the CPTC South Hill campus,” said Korschinowski, adding that A&P and avionics technician courses will not be interrupted by the closure.

She said the school has spent years preparing for this.

“This is our busiest flying time of year,” she said. “We have been doing lots of strategic planning just waiting for this to happen. A few years ago we heard it was going to happen, and then it didn’t, and then it did, and we hired extra staff to keep up with the demand for training and we kept the students informed.”

Aircraft Owners

Private owners who kept their airplanes in hangars or tied down on the KPLU ramp have also been in scramble mode to find a place to put their machines or risk leaving them to lie dormant for four months.

Ramp space in the Seattle and Tacoma area can be hard to find and expensive. Many pilots have resorted to parking their airplanes at local airparks, such as Shady Acres and Crest, while others were lucky enough to find space at Auburn airport, most of them on the south ramp tie-down area.