PANS-OPS (ICAO Doc 8168, Aircraft Operations)

PANS-OPS is the short name for ICAO Doc 8168, Procedures for Air Navigation Services — Aircraft Operations. As a PANS document it sits alongside the Standards and Recommended Practices in the Annexes rather than inside them: the material is too detailed and too operationally specific for full Standard status, yet it is applied worldwide, so ICAO publishes it as procedures. PANS-OPS governs two connected things — how instrument flight procedures are constructed by procedure designers, and how those procedures are flown by pilots.

Doc 8168 is organized into volumes. Volume I, Flight Procedures, is written for the operational user — the pilot and operator — and covers how procedures are to be flown: departure, approach, holding, altimeter setting, and the operational application of criteria such as minima. Volume II, Construction of Visual and Instrument Flight Procedures, is written for the specialist procedure designer and sets out the geometric and obstacle-clearance criteria used to build a procedure — protected areas, minimum obstacle clearance, gradients, and turn assumptions. A further volume addresses aircraft operating procedures for flight crews. Together these volumes mean that the plate a pilot loads for an ILS, an RNAV approach, a SID or STAR, or a holding pattern is the visible product of PANS-OPS design criteria, and the way that procedure is flown is governed by PANS-OPS operational criteria.

Obstacle clearance is the heart of Volume II. The criteria define the areas that must be kept clear around each segment of a procedure and the minimum clearance the aircraft is guaranteed above obstacles within them, which in turn drive the published minima — the Obstacle Clearance Altitude/Height (OCA/OCH) from which decision altitudes and minimum descent altitudes are derived. These criteria interact directly with the aircraft approach category concept: because faster aircraft need a larger turn radius, PANS-OPS ties the size of the protected areas and the applicable minima to the aircraft's category, which is based on its threshold speed. A pilot reading minima by category on an approach plate is reading a direct consequence of PANS-OPS design assumptions.

The most important comparison for internationally operating pilots is between PANS-OPS and the United States' TERPS (United States Standard for Terminal Instrument Procedures). Both systems achieve safe instrument procedures, but they make different assumptions and therefore produce different protected areas and minima. The best-known divergence is the circling approach: PANS-OPS and TERPS assume different turn radii and apply obstacle clearance differently, so the circling area and the associated minima are not the same. The two systems also treat missed-approach and departure climb gradients differently — TERPS works from a 200 ft per nautical mile standard on an all-engines basis, while PANS-OPS uses a 2.5 percent design gradient as its baseline — which is why a procedure that looks familiar can behave differently depending on which criteria built it. A pilot trained in one system who flies in the other must understand that the numbers on the plate were computed under different rules, even when the symbology looks alike.

For an ATO training pilots who will fly internationally, PANS-OPS is the reason a solid instrument syllabus cannot stop at teaching a student to fly a needle. Cadets need to understand that approach and departure minima are not arbitrary — they descend from a defined body of design criteria — and that those criteria differ between the PANS-OPS world and the TERPS world. A graduate who has only ever internalized one system's assumptions can be quietly surprised abroad, where the same category of approach yields different minima or a different circling area. Building that awareness into ground and simulator training is part of producing a pilot who is genuinely internationally capable.

For operators, PANS-OPS underpins the minima that appear in operations manuals and the assumptions behind performance-based navigation procedures. When an operator publishes company minima, or when it evaluates whether a particular aerodrome procedure is within its aircraft's and crew's capability, it is working downstream of PANS-OPS criteria. Understanding that origin makes it easier to reason about why a given approach carries the minima it does, and to brief crews accurately when operating across regions that use different procedure-design standards.

Aviatize's Training Management module lets an ATO structure an instrument syllabus that tracks not just hours flown but the specific procedures and competencies a cadet must demonstrate — approaches by type and category, departures, and holds — so the training record reflects genuine procedural understanding rather than raw time. Instructors can see at a glance which procedure types a student has covered and where gaps remain before a skill test.

The Ground Training & Checking module supports the classroom and briefing side of the same competency, recording the theoretical knowledge — minima derivation, approach categories, and the differences between procedure-design systems — that a pilot needs before applying PANS-OPS-built procedures in the aircraft.