Saint Clair County International (KPHN), Michigan
Landing essentials
Whether you can land, whether you can refuel, and how customs works here.
Overview
St Clair County International Airport, KPHN, sits near Port Huron, Michigan, roughly 44 nautical miles from the metro area it serves. The airport is a public, non-towered field with two paved asphalt runways and on-site customs inspection services, a combination that supports cross-border traffic on the Michigan-Ontario corridor. Fuel is available in 100LL and A+ grades, with Jet A also on the field, and the airport keeps a published attendance schedule of 0800 to 1700 daily.
Runways
Saint Clair County International has two paved runways. The longest, 04/22, is 5,104 ft long and 100 ft wide, with an asphalt surface.
Runway geometry from published threshold coordinates. Not for navigation.
Runways are listed longest first.
Source: FAA Form 5010.
Fuel and airfield services
Saint Clair County International has Jet A+ and 100LL available on the field. Fueling is available from 8am to 5pm, daily, and the airport has no control tower.
Source: FAA Form 5010 / NASR.
Customs
Saint Clair County International has US Customs and Border Protection clearance available onsite, with general clearance for international arrivals. A USDA compliance agreement is in place.
Source: CBP list of ports of entry.
Business aviation traffic
Saint Clair County International recorded 1,036 business aviation movements in 2025. Traffic peaks in June and July. Business aviation traffic at KPHN is concentrated in the summer months, peaking in June and July according to FAA TFMSC data for 2025.
Business jet movements, FAA TFMSC count. Peak month June, 150 movements in 2025.
Source: FAA TFMSC, business jet movements, 2025.
Climate
Weather station is 5.8 NM from the field. Some values are estimated by the agency. 1991–2020 climate normals.
Source: NOAA NCEI.
Operating constraints
Saint Clair County International has published operating constraints in four categories: access, runway notes, environmental and other notes.
For clearance delivery, contact Selfridge Approach. When Selfridge Approach is closed, contact Cleveland ARTCC instead.
Runway lighting is pilot-activated via CTAF: MALSR on runway 04; REIL on runways 22, 10, and 28; PAPI on runways 10 and 28; HIRL on runway 04/22; and MIRL on runway 10/28. PAPI on runways 04 and 22 operates continuously.
Deer and large birds are present on and in the vicinity of the airport.
Flights arriving from outside the United States must notify US Customs one hour prior to entry into the US. Operators must also notify the US Department of Agriculture and the airport manager 24 hours prior for disposal of international aircraft trash.
Source: FAA Chart Supplement.
Nearby airfields
Saint Clair County International has five airfields within 37 NM. The closest is Chris Hadfield Airport (CYZR), 11.03 NM northeast.
Part of the Detroit and Pontiac area.
Source: Skystar calculation from official coordinates.
Skystar at KPHN
We arrange catering, fuel and trip support here. Supplier prices reach you unchanged; our coordination fee sits on its own line.
The same order, priced two ways.
$2,400.00 catering order at KPHN.
Unchanged.
What the kitchen invoices us is what your quote reads.
One line, fixed.
It does not move with the size of the order.
At cost.
Passed on at the exact amount the processor took.
Market practice figures are industry averages, not a specific competitor.
Frequently asked questions
Does KPHN have on-site customs service?
St Clair County International Airport, KPHN, provides on-site customs service through CBP inspection agents. The airport also operates under a USDA compliance agreement covering agricultural inspection needs. Flights arriving from outside the United States must notify CBP one hour before entry into the US. Operators carrying international trash on board must notify the USDA and the airport manager 24 hours ahead of disposal. These notification requirements apply regardless of aircraft type or origin.
What runways are available at St Clair County International Airport?
St Clair County International Airport, identified as KPHN, has two paved asphalt runways. Runway 04/22 is the longer of the two at 5,104 feet by 100 feet wide. Runway 10/28 measures 4,000 feet by 75 feet wide. Both runways support a maximum paved landing distance of 5,104 feet at the field. Neither runway is listed as having a control tower, as KPHN is a non-towered airport.
Is KPHN a towered airport, and how does lighting activation work?
KPHN, St Clair County International Airport, is non-towered, so pilots coordinate on the common traffic advisory frequency. Runway lighting is pilot-activated: MALSR on runway 04, REIL on runways 22, 10, and 28, HIRL on runway 04/22, and MIRL on runway 10/28 are all activated via CTAF. PAPI is installed on runways 10 and 28 with pilot activation, while PAPI on runways 04 and 22 operates continuously. Pilots should plan CTAF calls accordingly when arriving after hours.
Who handles clearance delivery for flights at KPHN?
Clearance delivery for St Clair County International Airport, KPHN, is handled by Selfridge Approach. When Selfridge Approach is closed, pilots should contact Cleveland ARTCC instead for clearance delivery. This arrangement reflects the airport's non-towered status, since local clearance functions are routed through the nearest approach facility. Dispatchers filing IFR should account for this handoff point when the primary approach control is unavailable.
When is business aviation traffic busiest at St Clair County International Airport?
Business aviation traffic at St Clair County International Airport, KPHN, concentrates in the summer months. June and July are the peak months, according to FAA TFMSC data for 2025, with ops climbing well above the levels seen in winter months like January and February. Traffic tapers gradually through the fall before dropping to its lowest points in the December through February window. Operators planning summer trips into KPHN should anticipate this seasonal increase in activity.