Airport Of The Month – Winsted

When runways were invented, they were mostly grass, at least in Minnesota.

A strip of land was graded and rolled until it was fairly smooth and flat, then grass was planted and a turf runway came into existence. Not much engineering was involved and the quality was pretty variable.

Winsted Municipal Airport had a turf runway, but the subsoil was rather poor and the turf surface would get rutted and have a "washboard" effect. The drainage needed some work and the lighting system became badly out of date. Not an ideal situation and one that required a lot of maintenance.

The city started looking into making it a hard surface runway, but there were complications with zoning and land. To pave the runway, a business and a road would have to be relocated so the decision was made to reconstruct the turf.

They got some engineering help and went to work. State and federal grants were secured and construction began in 2019 with the relocation of a gas pipeline that was under the runway. Wet weather delayed that work so the runway construction didn't start until 2020 and everything was finished except for getting grass to grow. Ironically for a project that started with a "rain delay," the 2021 growing season was mostly a drought so the opening was delayed until that October.

Proving that airport engineering is money well spent, the new turf runway has a very innovative design. The existing topsoil was removed and edge drains installed. A layer of compacted borrow was placed to assure a good foundation then topped with 12 inches of select granular material.

This subbase was covered with geotextile fabric to provide strength and the whole thing surfaced with 9 inches of "Aggregate Turf Pavement," that's P-217 in FAA speak. FAA pavement specifications are contained in an Advisory Circular (150/5300-10) including every possible combination of aggregates and binders.

"This item shall consist of an aggregate-turf composed of a base course of soil-bound crushed stone, soil-bound gravel, or soil-bound sand and a seedbed of suitable soil or a combination of soil and aggregate constructed on a prepared subgrade or a previously constructed underlying course..." and so on.

The city installed new Medium Intensity Runway Lights (MIRLs) and replaced the below ground fueling system with a new above ground, self-service unit. An already delightful airport is now significantly better.

Winsted is a popular place with 40-plus hangars and an estimated 13,500 operations each year. If you're just stopping by the Winsted Arrival/Departure Building has all the facilities for a nice stay and is open 24/7. Half a dozen restaurants are within a mile of the parking area.

Better yet you can camp with your aircraft. Just south of the airport is the site of the "Winstock Country Music Festival" that happens for three days during the first two weeks in June and supports the Holy Trinity Catholic School system.

Poor soil and drainage might have been why the runway needed reconstruction but an alternate theory goes back to the first airshow at the Winsted Municipal Airport on July 31, 1966. Minnesota Flyer Founder Sherm Booen was the Master of Ceremonies and arranged a fly-by with Capt. Spencer Marsh of Northwest Airlines. Marsh grew up in nearby Glencoe and was instructor on a training flight in a Boeing 707 that day.

A very sedate "low" pass at about 500 feet above the runway so everyone could take pictures was expected. As it turned out, the 707 lined up on final approach, gear and flaps down. At 10 feet above the threshold, the crew applied power, leveled off, and flew the length of the runway.

The blast from the four jets scorched some grass and the wing tip vortices put a couple little tail draggers on their nose, but without any damage to the airplanes.

Possibly the turf never recovered from being burned by an airliner, or Capt. Marsh scared the fescue out of 50 years of growth. In any case, the runway at Winsted is now first class thanks to some excellent engineering.