Approach Chart Symbols - What Every IFR Pilot Must Know Cold

Approach chart symbology is a language, and gaps in that vocabulary become hazardous when you’re flying in actual IMC. This guide breaks down every major symbol on an instrument approach plate - what each one means, where it appears, and why it matters at the exact moment you need it.

The Maltese Cross: Final Approach Fix on Non-Precision Approaches

The Maltese cross marks the Final Approach Fix (FAF) on non-precision approaches. It appears on VOR approaches, RNAV approaches without vertical guidance, and NDB approaches. On an ILS approach, the glideslope itself serves this function - so the Maltese cross is absent.

Crossing the FAF is the trigger for final descent toward the runway environment. At that point, confirm your altitude, set timing if you’re using it to identify the missed approach point, and begin descent.

One critical distinction: the FAF is a point, not the approach course itself. You can be established on the final approach course well before reaching the FAF. Descending to step-down altitudes before crossing it is a violation - and in IMC, a potential safety hazard.

Step-Down Fixes: The Descent Is a Staircase, Not a Slope

Step-down fixes appear on the profile view as small triangles. They define altitude constraints along the final approach segment, placed specifically for terrain and obstruction clearance.

You cannot descend below the altitude associated with a step-down fix until you have passed it. The descent from FAF to minimums follows a structured staircase with mandatory floors at each step. Treating it as a continuous glide path is a misread of the procedure.

The Visual Descent Point (VDP)

The VDP is marked on the profile view with a bold “V” symbol. It identifies the point on final approach from which a normal descent from the Minimum Descent Altitude (MDA) to the touchdown zone can be made.

Reaching the VDP without the runway environment in sight means the remaining distance is insufficient for a safe, stabilized descent to the runway. The VDP is not a mandatory missed approach trigger the way the missed approach point is - but treating it as one is sound judgment. Pilots who press past the VDP with nothing in sight have poor odds of making the runway safely.

Briefing Strip Symbols: The T and A Inverted Triangles

Two symbols in the briefing strip - the block of data running across the top or bottom of the plate - govern critical pre-flight decisions and are not optional reads.

The bold T in an inverted triangle signals non-standard takeoff minimums or specific departure procedures. Standard takeoff minimums are one statute mile visibility for single- and twin-engine aircraft. If the T appears, those standards do not apply at that airport. The actual requirements are published separately in the approach plate booklet or digital navigation source. Departing in low visibility without checking this symbol is a planning failure, not a procedural technicality.

The A in an inverted triangle flags non-standard alternate minimums. Standard alternate filing requires either a precision approach with 200-foot ceilings and ½-mile visibility, or a non-precision approach with 600-foot ceilings and 2-mile visibility. If the A is on the plate, those numbers may be higher - or the airport may not be authorized as an alternate at all. If that airport appears in your flight plan as an alternate, the A demands a check before departure.

Approach Lighting Symbols and Their Effect on Minimums

The airport diagram portion of the plate uses distinct symbology for different approach lighting systems, and the differences affect published minimums directly.

A full Approach Lighting System with Sequenced Flashing Lights (ALSF) - common at towered airports - is depicted differently from the Simplified Short Approach Lighting System (SSALS) used at smaller fields. Some approach procedures publish lower minimums specifically when a certain lighting system is operational. If a NOTAM shows that system out of service, your minimums increase. Briefing the lower number without confirming the lighting system status is a common source of minimum busts.

Aircraft Category and Approach Minimums

Approach plates organize minimums by aircraft category - A, B, C, and D - based on approach speed: 1.3 times the stall speed in the landing configuration.

• Category A: Up to 90 knots (typical for a Cessna 172)
• Category B: 91–120 knots
• Category C: 121–140 knots
• Category D: 141–165 knots

If you intentionally fly faster than your category’s speed threshold - to handle gusts, for example - you should technically apply the higher category’s minimums. Flying category A minimums while operating at category B speeds is a discrepancy with real safety implications on short final. Examiners on instrument check rides watch for this.

Procedure Turn Symbology: The Barb and NoPT

The procedure turn barb on the plan view indicates the direction of the course reversal and which side of the course the turn should be flown. The plate also specifies the maximum distance from a fix within which the procedure turn must be completed.

NoPT means no procedure turn is authorized on that routing. This applies when you’re arriving from a direction that already aligns you with the inbound course, or when ATC is vectoring you to intercept final. Flying a procedure turn after receiving radar vectors to final creates traffic separation problems. NoPT means proceed inbound - no reversal.

The holding-in-lieu-of-procedure-turn (HILPT) uses the familiar racetrack holding pattern symbol. It means you execute a holding pattern entry rather than a traditional course reversal. The technique mirrors standard holding, but the timing and configuration context is specific to the approach. Know which one is depicted before you brief.

RNAV Waypoint Symbology: The Modern Standard

As GPS-based approaches have become standard at thousands of U.S. airports, the plate symbology for RNAV procedures has evolved to reflect their fix architecture:

• IAF (Initial Approach Fix): Depicted with a flag symbol
• IF (Intermediate Fix): Distinct symbol from the IAF
• FAF: Retains the Maltese cross

Understanding where these fixes fall - and what course and altitude constraints apply at each one - is now the core competency for IFR flying. Most pilots are flying RNAV approaches far more frequently than VOR or NDB procedures. These plates deserve the same deliberate study that older procedures historically received.

Briefing the Missed Approach Before the Approach

On precision approaches, the missed approach point is defined by the Decision Altitude (DA) - you reach it and make your call. On non-precision approaches, it’s defined by a fix, a DME reading, or timing from the FAF. The profile view symbol shows exactly where it falls.

The discipline that separates proficient IFR pilots from those who create incidents is straightforward: brief the missed approach before starting the approach, every time. Know the initial instructions, the turn direction, the climb altitude, and the holding fix or routing. Arriving at the missed approach point in reduced visibility with no plan already formed means making real-time decisions in conditions where terrain and traffic leave no margin for hesitation. That is not when you want to be reading the plate for the first time.

Key Takeaways

• The Maltese cross marks the FAF on non-precision approaches; it is a point, not the course - no descent below step-down altitudes until you’ve crossed it.
• Step-down fix triangles on the profile view define mandatory altitude floors along the final approach segment; the descent is a staircase with rules, not a continuous slope.
• The T and A inverted triangles in the briefing strip govern non-standard takeoff minimums and alternate filing requirements - both require a separate lookup and neither is optional.
• The VDP marks the last practical point for a stabilized descent to the runway; reaching it with no runway environment in sight is a strong signal to execute the missed approach.
• RNAV approach symbology (IAF flag, IF, FAF Maltese cross) reflects the fix architecture of GPS-based procedures that now dominate IFR flying - fluency with these plates is the baseline for modern instrument currency.
• Always brief the missed approach procedure before beginning the approach. Never at the moment you need it.