Learn how to read an instrument approach chart, including fixes, courses, altitude constraints, minima, missed approaches and simulator mismatches.
Read an instrument approach chart in a fixed order: confirm the airport, runway, procedure and revision; study the plan view and frequencies; trace every fix and altitude in the profile; select the correct minima; then brief the missed approach. In real-world aviation and flight simulation, never use one panel in isolation.
Across our Aviation & Real-World Flying guidance, we use approach chart and approach plate to mean the same document. Layouts and symbols vary between national authorities and chart publishers, so the chart's own legend always takes precedence. For real flying, use only current, authorised charts and approved navigation data.
Instrument approach chart sections explained
An approach chart combines a top-down route, a vertical descent profile, operating notes, landing minima and missed-approach instructions.
| Chart section | What to extract | Common trap |
|---|---|---|
| Header, notes and briefing strip | Airport identifier, procedure title, runway, chart revision, restrictions, required equipment and communications | Selecting the wrong Y/Z procedure or overlooking a procedure-not-authorised note |
| Plan view | IAFs, transitions, courses, distances, holds, procedure turns, terrain sectors and final approach track | Assuming north is up without checking the orientation symbol |
| Profile view | Crossing altitudes, step-down fixes, FAF or FAP, descent angle, glideslope intercept, MAP and runway elevation | Reading a minimum altitude as a mandatory crossing altitude |
| Minima table | DA/H or MDA/H, visibility, aircraft category and straight-in or circling line | Choosing the lowest figures despite having the wrong equipment or approach category |
| Missed approach | Initial climb, track or heading, turn direction, holding fix and final altitude | Turning immediately when the procedure requires a climb before the turn |
| Airport sketch | Runway arrangement, lighting and touchdown-zone or airport elevation | Treating the small sketch as a substitute for the full airport diagram |
If the different chart families are unfamiliar, our explanation of how aviation charts fit together in a simulator provides the wider context without duplicating the approach briefing itself.
How do I brief an instrument approach chart?
Brief the chart from identification through to the missed approach, following the same sequence every time so that an omission is obvious.
- Confirm the procedure. Match the airport identifier, runway, approach type and any suffix such as Y or Z. Check the issue or effective information and make sure the runway has not been renumbered in your simulator scenery.
- Read every note. Look for required DME, GNSS, SBAS, RNP capability, temperature limits, remote-altimeter restrictions, speed limits and equipment failures that alter the minima. One note can make an otherwise suitable approach unavailable.
- Match the expected clearance. Identify the IAF, transition, feeder route or vectors-to-final entry you expect to use. Loading a full transition while accepting radar vectors can make the autopilot turn back towards an unwanted fix.
- Set and identify navigation sources. Record the localiser or navaid frequency, identifier, inbound course and relevant communications. Even if the aircraft tunes automatically, verify the displayed source and identifier.
- Trace the lateral path. Follow the cleared route through the IAF, intermediate fixes, FAF or FAP, runway and MAP. Include turn directions, holds, DME references and any maximum speeds.
- Trace the vertical path. Read each minimum, maximum or mandatory altitude in order. Note the published glideslope-intercept altitude, step-down fixes and descent angle; an FMS-drawn path is not permission to ignore a charted restriction.
- Select the minima. Choose the line matching the navigation capability actually available and the correct aircraft category. Set the barometric reference and DA or MDA in the aircraft, including any charted adjustment.
- Brief the landing cues. Identify the runway lighting, touchdown-zone elevation and visual references needed to continue. Confirm that the planned descent can produce a normal landing rather than a rushed dive after breaking cloud.
- Read the missed approach verbatim. State the initial climb, any climb-before-turn requirement, heading or track, holding fix and altitude. Finally, compare the loaded avionics procedure with the chart fix by fix.
How do I interpret fixes and altitude restrictions?
Fix symbols establish where a restriction applies, while the profile view shows what altitude must be maintained or crossed there.
- Minimum, maximum and mandatory altitudes: on many US-style charts, a line beneath an altitude means at or above, a line above means at or below, and both lines mean mandatory. Other chart styles differ, so check the legend rather than relying on typography from memory.
- FAF or FAP: this marks the start of the final approach segment. A non-precision FAF may use a Maltese-cross symbol; an ILS final approach point is normally defined by intercepting the glide slope at the published altitude.
- MAP: the missed approach point may be defined by a fix, DME distance, timing or runway threshold. A visual descent point is not the MAP and does not authorise descent without the required visual references.
- MSA: minimum sector altitude normally supplies emergency obstacle clearance within the depicted area, commonly 25 NM, but it is not a cleared route altitude and may not guarantee navigation reception. A terminal arrival altitude has a different procedural role.
- Distance labels: determine whether a figure is DME from a specific station, distance between fixes or distance to the threshold. They are not automatically interchangeable.
How do I choose the correct approach minima?
Choose the minima row by the guidance and equipment available, then use the aircraft category required for the planned approach speed.
| Minima line | Required guidance | How it is flown |
|---|---|---|
| ILS | Valid localiser and glide slope | Use DA/H; initiate the missed approach at DA if the required visual references are absent |
| RNAV LPV or LNAV/VNAV | The charted GNSS, SBAS or vertical-navigation capability | Normally uses DA/H; LPV resembles an ILS operationally but is not an ILS |
| RNAV LNAV, VOR, NDB or localiser-only | Valid lateral guidance | Usually uses MDA/H; advisory vertical guidance does not convert it into a DA approach |
| Circling | Approach guidance followed by visual manoeuvring | Use the separate circling MDA/H, visibility and category restrictions |
DA is a decision point: if continuation requirements are not met, begin the missed approach rather than levelling at DA. At an MDA, do not descend below the published altitude until authorised by the required visual references and landing position. If still not visual, do not turn away from the protected final path before the MAP unless the procedure or ATC permits it.
Approach categories are not simply labels for small and large aircraft. Use the category required by the governing rules for the planned speed, moving to a higher category when necessary. For procedures with navigation-performance requirements, see how equipment capability and charted limits shape an RNP approach; an RNP AR procedure also requires specific real-world authorisation.
Why does the approach chart not match my simulator?
A chart and simulator usually disagree because the scenery, navigation database and chart come from different revision cycles.
- The database may contain renamed fixes, changed altitudes or a different Y/Z procedure.
- Older scenery may use a previous runway number even though the navigation database follows the newer magnetic designation.
- The FMS may omit a vectors transition, represent a hold differently or insert a route discontinuity.
- The chart may offer LPV or another minimum that the simulated avionics cannot support.
- A one-degree course difference can result from rounding or magnetic-variation updates rather than an incorrectly coded procedure.
First verify the airport and runway, then compare the chart revision with the navigation-data cycle and load the exact transition. Check every fix, course and altitude instead of trusting the magenta line. A mismatched historical setup can still be used as a documented simulator exercise, but it is not suitable operational material for real flight.
Which instrument approach chart mistakes matter most?
The most serious reading errors involve descent authority, minima and the missed approach rather than the chart's cosmetic details.
- Using MSA as a descent clearance: remain on the published segment altitude unless cleared and established as the applicable rules require.
- Following advisory VNAV below an MDA: a generated glidepath remains advisory when the selected minima line is LNAV, VOR or localiser-only.
- Capturing an ILS from above: intercept the glide slope from below at the charted altitude while established on the localiser; an unexpected capture outside that geometry needs investigation, not blind acceptance.
- Choosing minima by aircraft type alone: confirm the actual approach category, equipment line, visibility and any conditional notes.
- Mixing units or pressure settings: check feet versus metres, nautical miles, QNH and whether the simulator displays hectopascals or inches of mercury.
- Turning early after going missed: follow the published sequence. Climb-before-turn restrictions protect against obstacles that may be close to the final approach path.
What should a complete approach briefing include?
A complete briefing states the procedure, route, vertical constraints, minima, landing requirements and missed approach in a compact, repeatable order.
Approach and runway; transition or vectors; navigation source and frequency; final course; FAF and crossing altitude; DA or MDA and visibility; runway lighting; missed-approach track, altitude and hold; special restrictions or threats.
Keep the briefing short enough to complete before the high-workload final segment. Practising the chart as part of a complete simulator IFR flight exposes FMS and clearance problems early. Where no approved vertical path is provided, use the charted distances and altitudes to convert the descent profile into a practical vertical-speed target.