Charles M. Schulz–Sonoma County Airport (IATA: STS, ICAO: KSTS, FAA LID: STS) is 7 miles (11 km) northwest of downtown Santa Rosa, in Sonoma County, California.^[1][2]

The airport is named after Charles M. Schulz, the famed cartoonist of the Peanuts comic strip, who lived in Santa Rosa for more than 30 years. The airport's logo features Snoopy in World War I flying-ace attire atop his doghouse.

In the 1930s Santa Rosa had a small municipal airfield owned by Richfield Oil Corporation next to the Redwood Highway about 6 miles southeast of the present airport. Use of the 3,000-foot sod runway at the earlier airfield was discontinued during World War II as facilities at the present airport improved.^[3]

Opened in June 1942 and known as Santa Rosa Army Air Field, the airfield was assigned to Fourth Air Force as a group and replacement training airfield. Known units assigned to Santa Rosa were:

The 478th Fighter Group was permanently assigned to Santa Rosa in December 1943 and began training replacement pilots, who were sent to combat units overseas after graduation.

The airfield was inactivated on January 31, 1946 and turned over to the War Assets Administration for eventual conversion to a civil airport.

From the late 1940s to the mid 1970s Southwest Airways and successors Pacific Air Lines, Air West and Hughes Airwest served Santa Rosa. Southwest Airways Douglas DC-3s followed by Pacific, Air West and Hughes Airwest Fairchild F-27s mainly flew to San Francisco.

Commuter airlines flew STS to San Francisco until 2001, and sometimes to San Jose. In the mid 1970s Eureka Aero was flying nonstop to Eureka and Sacramento.^[4] In 1985 Westates Airlines Convair CV-580s flew nonstop to Los Angeles Los Angeles for several months before ceasing operations; their July 1985 timetable listed 38 round trips a week between STS and LAX. Other turboprop flights included American Eagle Fairchild Swearingen Metroliners operated by Wings West Airlines for American Airlines nonstop to SFO and San Jose SJC. In late 1989 American Eagle had three Metros a day to SFO and four a day to SJC.^[5] Reno Air Express had code share BAe Jetstream 31s to San Jose flown by Mid Pacific Air for Reno Air.

In the mid 1980s United Airlines entered into a code sharing agreement with WestAir, a commuter airline that had previously served STS with Cessna 402s and de Havilland Canada DHC-6 Twin Otters to San Francisco.^[6] WestAir then began flying as United Express to SFO until 2001.^[7] Westair used the Embraer EMB-110 Bandeirante, Short 360, BAe Jetstream 31 and Embraer EMB-120 Brasilia.^[8]

In 1989 jet service arrived in Santa Rosa when WestAir (United Express) began four weekday BAe 146-200 nonstops to Los Angeles, soon replaced with Embraer EMB-120 Brasilias, the turboprop service ending in 1991. The Westair BAe 146s were Santa Rosa's only jet flights until Allegiant Air jets appeared on May 19, 2016 followed by American Eagle on February 16, 2017.^[9] WestAir formerly operated as Stol Air Commuter flying Britten-Norman Islanders and Trislanders to San Francisco. Stol Air Commuter had administrative offices in Santa Rosa. United Express left Santa Rosa in 2001 and the airport had no scheduled passenger service several years.

In March 2007 airline service resumed; Horizon Air, a subsidiary of Alaska Airlines, began flights to Seattle/Tacoma and Los Angeles. Horizon added flights to Portland, Oregon in late 2007, to Las Vegas in early 2008,^[10] and to San Diego in mid-2012.

In early 2011 Alaska Airlines announced it would retire its Horizon brand;^[11] and all flights operated by Horizon now use the Alaska Airlines name. In June 2012 the airline ended flights from STS to Las Vegas.^[12]

As part of an agreement between the airport, Alaska Airlines, and the local enotourism industry announced in January 2012 that passengers are allowed to check a 12 bottle case of wine for free on all Alaska Airlines flights from the airport.^[13]

Alaska Airlines flights from Santa Rosa are 76-seat Embraer 175s or 76-seat Bombardier Q400s. Q400s currently fly nonstop to Los Angeles, Orange County, Portland, San Diego and Seattle.^[14]

In March 2016 Allegiant Air announced it would begin flying McDonnell Douglas MD-83s nonstop to Las Vegas McCarran International Airport and nonstop to Phoenix-Mesa Gateway Airport (IWA).^[15] The Las Vegas flight began on May 19, 2016 and the Phoenix flight several days later. The MD-83 was the largest airliner ever scheduled to Santa Rosa; as of October 19, 2016, Allegiant switched from the 166 seat MD-83 to the 155 seat Airbus A319. Allegiant ended flights to Phoenix-Mesa on January 2, 2017 and to Las Vegas on June 30, 2017 and no longer serves Santa Rosa.

In October 2016 American Airlines announced it would begin nonstop service between Santa Rosa and its hub in Phoenix (PHX) on February 16, 2017. The daily code share flight was being operated by SkyWest Airlines as American Eagle with Canadair CRJ-700s. American Eagle then added a second nonstop CRJ-700 roundtrip flight to Phoenix and now has one Canadair CRJ-900 a day between Phoenix and Santa Rosa.^[16] American Eagle announced it would begin flying Embraer 175s nonstop to Los Angeles (LAX) effective May 3, 2019 and nonstop to Dallas/Fort Worth (DFW) effective June 6, 2019. American Eagle now has nonstop jets to DFW, LAX and PHX from Santa Rosa.^[17]

In February 2017 United Express announced their return to Santa Rosa with thrice daily service to the United Airlines hub in San Francisco (SFO). The flights began on June 8, 2017; SkyWest Airlines Canadair CRJ-200s operate the code sharing flights for United. United Express announced it would begin nonstop regional jet flights to Denver on March 8, 2019 .^[18]

In March 2017 Sun Country Airlines announced seasonal nonstop service between Santa Rosa and Minneapolis/St. Paul International Airport, to operate from late summer until late fall.^[19] Sun Country was operating weekly 162 seat Boeing 737-800s August 24, 2017 through December 3, 2017, connecting via Minneapolis/St. Paul to Boston, New York John F. Kennedy Airport and Washington Reagan National Airport. Sun Country still operates from the airport but has ended all service to Ronald Reagan Washington National Airport and now serves Washington Dulles Airport instead.^[20] In May 2018 Sun Country Airlines made a surprise announcement that it would be adding a new seasonal destination from Santa Rosa with nonstop flights between STS and Las Vegas (LAS) in addition to its seasonal nonstop service between the airport and MSP. The Sun Country fleet is Boeing 737-700s and 737-800s, the largest aircraft scheduled to the airport.^[21]

The airport covers 1,125 acres (455 ha) at an elevation of 129 feet (39 m). It has two asphalt runways: 2/20 is 5,202 by 100 feet (1,586 x 30 m) and 14/32 is 6,000 by 150 feet (1,829 x 46 m).^[1]

In 2017 the airport had 79,231 aircraft operations, average 217 per day: 83% general aviation, 10% air taxi, 6% airline and 1% military. 315 aircraft were then based at this airport: 85% single-engine, 12% multi-engine, 2% jet, and 1% helicopter.^[1]

In August 2013 the airport started a project to decouple the ends of the two runways and extend runway 14/32 by 885 feet, to 6000 feet and extend runway 2/20 by 200 feet, to 5202 feet. This project was scheduled for completion in November 2014.^{[22] [23]}

A Sonoma–Marin Area Rail Transit station bearing the name of the airport was constructed about 1.5 miles (2.4 km) from the airline passenger terminal on Airport Boulevard^[24] and shuttle buses are currently serving as the link between the two locations as this passenger rail service is now in operation. Sonoma County Airport Express buses connect the airport with Oakland International Airport and San Francisco International Airport.^[25]

Depending on the month of the year, current Alaska Airlines service operated by Horizon Air features a total of seven or eight departures a day from Santa Rosa with two or three nonstop flights a day to Los Angeles (LAX), one or two nonstop flights to Portland (PDX), Seattle (SEA), and one nonstop flight a day to Orange County (SNA), and San Diego (SAN).^[14]

The Sonoma Air Attack Base of the California Department of Forestry and Fire Protection (known as CDF or CAL FIRE) was established in 1964 at the northeast corner of the airport. Sonoma responds to an average of 300 calls per year. It has a battalion chief and a fire captain (air tactics group supervisors), a fire apparatus engineer (base manager) and six firefighters. Aircraft at Sonoma include one OV-10 Bronco (Air Attack 140) and two Grumman S-2 Tracker air tankers (classified as S-2T's, Tankers 85 and 86.)

On average, the base pumps about 300,000 US gallons (1,000 m3) of retardant a year. With the base’s pumps, four loading pits and equipment, Sonoma has a possible peak output of 120,000 US gallons (450 m3) of retardant each day. The base’s immediate response area covers 4,000 square miles (10,000 km2) and includes Marin County and portions of the CDF Sonoma–Lake–Napa, Santa Clara, San Mateo–Santa Cruz, and Mendocino Units.

The Pacific Coast Air Museum is at the southeast corner of the airport, next to the hangar used in the 1963 Hollywood all-star comedy movie, It's a Mad, Mad, Mad, Mad World. Known as the Butler Building, the hangar was built during World War II and is still in use.