KSEA Seattle-Tacoma — Instrument Checkride Guide

What is KSEA and why does it matter for instrument training?

Seattle-Tacoma International Airport (ICAO: KSEA) is a Port of Seattle facility located approximately 10 miles south of downtown Seattle, Washington, at an elevation of 433 feet MSL. It is the primary commercial service airport for the Puget Sound region and operates inside Class B airspace under continuous ATC tower operations. Seattle Center (ARTCC) and Seattle Approach Control manage IFR traffic in and out of the terminal area around the clock.

For instrument students, KSEA's significance is less about conducting the checkride there and more about understanding the approach environment. The published procedures, the SEA VORTAC (116.80 MHz, on-field), and Seattle Approach's sequencing patterns are all commonly tested in oral scenarios. The airport's frequent IFR conditions mean that any pilot based in the Pacific Northwest will likely shoot a KSEA approach in actual IMC before long.

What instrument approaches are published at KSEA?

KSEA has ILS or LOC, RNAV (GPS), and RNAV (RNP) approaches published to all six runway ends, covering both north and south flow operations across three parallel runways. The ILS to runways 16C, 16L, and 16R carries an ILS classification code of IIIE, enabling low-visibility operations down to Cat III minimums. Standard Cat I, Special Authorization Cat I, and Cat II procedures are also charted for the respective runway ends.

Special departure procedures apply at KSEA; consult the published ODP or SID before filing an IFR departure. Current approach charts are available from the FAA Aeronav Terminal Procedures Publication.

What is the runway configuration at KSEA?

KSEA operates three parallel concrete runways oriented roughly north-south (164°/344° magnetic). All three runways support precision approaches in both directions and are equipped with centerline lighting, RVR sensors, and 4-light PAPI systems. Runway lengths vary:

North flow (runways 34C/34L/34R) is used when winds favor a southerly landing direction; south flow (runways 16C/16L/16R) is more common and aligns with the prevailing northerly wind that dominates during clear weather. Parallel approach operations are conducted routinely between 16L and 16R (or 34L and 34R), which means instrument students should understand the staggered approach concept and simultaneous independent approaches when discussing KSEA in an oral exam.

What weather patterns should instrument pilots expect at KSEA?

The Pacific Northwest climate creates a distinct weather profile that makes KSEA one of the most IFR-intensive major airports in the continental U.S. The prevailing onshore flow from the Pacific carries moisture into Puget Sound year-round, but the effect is most pronounced from October through March, when marine stratus and low-level frontal systems routinely produce IFR ceilings and reduced visibility.

• Marine layer: Low stratus often settles in overnight, producing ceilings of 400–900 feet AGL with 1–3 mile visibility in mist or light drizzle. These conditions can persist through mid-morning even on days that ultimately become VFR.
• Pacific frontal systems: Active fronts move through every 5–10 days in winter, bringing sustained IFR ceilings, rain, and occasionally convective activity along prefrontal squall lines.
• Mountain obscuration: The Cascades to the east and the Olympic Range to the west create orographic lifting. Associated icing levels are a significant hazard for instrument flights between October and April.
• Summer: The prevailing marine high-pressure ridge produces predominantly VFR conditions from June through September, with afternoon thermal activity occasionally building towering cumulus near the mountains.

Pilots planning IFR arrivals into the Seattle terminal area should always review the Seattle-area AIRMETs on Aviation Weather Center's Graphical Forecasts for Aviation (GFA) and check the current D-ATIS on 118.0 MHz before contacting Seattle Approach.

What should you expect on an instrument checkride at KSEA?

Most instrument rating practical tests in the Seattle area do not originate at KSEA itself. The airport's Class B airspace, constant air carrier traffic, and general aviation parking restrictions (PPR required; contact 206-433-5481 during 0700–2100 local) make it logistically difficult for checkride operations. In practice, instrument checkrides in the Puget Sound area typically originate from reliever airports such as KBFI (King County International / Boeing Field) or KRNT (Renton Municipal), with KSEA approaches flown under Seattle Approach Control as part of the practical test route.

That said, KSEA approaches are a legitimate and frequently used checkride tool precisely because the environment demands precision. When Seattle Approach sequences a light training aircraft into the flow between commercial departures, the student is managing real ATC communication, runway assignment changes, and potential speed control requests — all of which the Instrument Rating ACS (FAA-S-ACS-8C) expects a candidate to handle competently.

A DPE using KSEA approaches in a checkride scenario will pay particular attention to several competencies. First, Class B clearance awareness: the candidate must demonstrate understanding of when a clearance is required and what to do if the clearance is not received before entering the Class B lateral or vertical limits. Second, approach briefing and currency: with six ILS runway ends and multiple RNAV variants published, the DPE may assign a runway change mid-brief to test whether the candidate can quickly transition to a new approach plate without losing situational awareness. Third, missed approach execution: KSEA's missed approach procedures involve climbs into active departure corridors; executing a missed approach and coordinating with Seattle Approach in a busy traffic environment is a realistic task that separates prepared candidates from those who have only practiced in sterile airspace.

The marine layer also creates authentic teaching moments during the oral. A DPE may present a scenario where the KSEA ATIS is reporting 600 overcast and 1.5 miles visibility and ask whether the filed alternate meets the alternate minima under 14 CFR 91.169. Because KSEA has precision approaches, its standard alternate minima are 600-2 (ceiling 600 feet and visibility 2 SM); the filed destination forecast at the time of that scenario would require an alternate unless the 1-2-3 rule is satisfied. Candidates who have internalized how Pacific NW weather interacts with alternate planning requirements tend to answer these questions fluently.

Finally, approach minimums under 14 CFR 91.175(c) are a high-probability oral topic at any airport with Cat II/III ILS capability. The DPE may ask what equipment and training requirements apply to fly a Cat II or Cat III approach, and what visual references are required to continue below DA at each category. Understanding the regulatory framework — not just the plate minimums — is what the ACS requires.

Practice Questions

1. KSEA is reporting 300 overcast and 1/2 mile visibility in fog. You are filing IFR to KSEA as your destination. Under 14 CFR 91.169, is an alternate airport required, and if so, what are KSEA's standard alternate minima given its published precision approaches?

2. Seattle Approach assigns you the ILS 16C while you are briefing the ILS 16L. You have 4 miles to the final approach fix. What steps do you take to comply with the new clearance, and what do you tell Approach if you need more time?

3. You are flying the RNAV (GPS) Y 16R at KSEA in a WAAS-equipped aircraft. The approach shows LPV minimums of DA 254 feet and RVR 1800. You arrive at DA with only the ALSF-2 approach lights visible. What does 14 CFR 91.175(c)(3) say about continuing below DA using approach lights alone?

4. What is the SEA VORTAC frequency, and how would you use it to identify your position on a hold-in-lieu-of-procedure-turn missed approach at KSEA?

5. ATC clears you for a simultaneous independent ILS approach to 16L while another aircraft is on the ILS 16R. What does "independent" mean in this context, and what are your responsibilities if you break out of the localizer course?

Frequently Asked Questions

Q: What class of airspace is KSEA?

KSEA operates inside Class B airspace. A clearance is required to enter the Class B, and instrument students conducting approach practice will be working with Seattle Approach Control, which issues clearances for every arrival into the Class B.

Q: What instrument approaches are published at KSEA?

KSEA has ILS or LOC approaches to all six runway ends (16C, 16L, 16R, 34C, 34L, 34R), RNAV (GPS) Y approaches to all six ends, and RNAV (RNP) Z approaches to all six ends. Three visual approach procedures (BAY, HUSKY, MALL) are also published.

Q: What are the ILS categories available at KSEA?

The ILS approaches to runways 16C, 16L, and 16R are classified Cat III (ILS classification code IIIE), enabling low-visibility operations. Standard Cat I and Special Authorization Cat I and II variants are also charted for those runways and for the 34-series runway ends.

Q: How often does KSEA go IFR?

The Pacific Northwest marine layer and persistent onshore flow make IFR conditions common at KSEA from October through March. Low ceilings of 400–900 feet with 1–3 mile visibility in mist or drizzle are routine during the rainy season. Summers are predominantly VFR.

Q: Is KSEA a realistic checkride location for instrument students?

Most instrument rating checkrides do not take place at KSEA itself due to its busy Class B airspace and heavy air carrier traffic. Training flights and checkrides typically originate from reliever airports such as KBFI (Boeing Field) or KRNT (Renton), using KSEA approaches under Seattle Approach control.

Q: What NAVAID is located at KSEA?

The SEA VORTAC is located on the field and operates on 116.80 MHz. It serves as the primary VOR fix for numerous IFR arrivals, holds, and en route segments in the Seattle terminal area.

Q: What D-ATIS frequency should I monitor at KSEA?

The D-ATIS at KSEA broadcasts on 118.0 MHz. Monitor it before contacting Seattle Approach or Clearance Delivery (128.0 MHz) to obtain the current weather, runway in use, and approach in use.

Sources

• AirNav — KSEA Seattle-Tacoma International Airport
• FAA Aeronav — Terminal Procedures Publication
• 14 CFR 91.169 — IFR Flight Plan: Alternate Airport Requirements
• 14 CFR 91.175 — Takeoff and Landing Under IFR
• FAA Instrument Rating ACS (FAA-S-ACS-8C)
• Aeronautical Information Manual — Chapter 3, Section 2 (Class B Airspace)
• Aviation Weather Center — Graphical Forecasts for Aviation (GFA)

This article was researched from FAA primary sources (ACS, FAR/AIM, Advisory Circulars, Instrument Flying Handbook) and citing current 14 CFR Part 91 — drafted by MockDPE. Last updated: May 2026. If you spot an inaccuracy, email corrections@mockdpe.org.