Slow approach — FDM event profile

01 · Monitoring purpose

What the profile screens for

Airspeed falls below the applicable target band at a validated approach gate or for a defined persistence period.

Why it matters

Low speed reduces stall and manoeuvre margin and may reflect energy, thrust, target, or windshear effects.

Flight-phase contextApproach

Risk lensesRunway excursion / abnormal runway contactTerrain collision / CFITOperational procedure deviation

02 · Candidate logic frame

Build the event around relationships—not one number.

01 · Gate

Define the operating context

Identify the approach state, aircraft configuration, location, and any required external data before applying logic.

02 · Detect

Screen the signal relationship

Use validated combinations of calibrated airspeed, target speed, angle of attack; avoid treating one isolated value as the whole event.

03 · Validate

Confirm it is a genuine event

Check polarity, units, source, recording rate, dropouts, air/ground logic, persistence, and false-positive mechanisms.

04 · Contextualise

Connect data to the safety question

Review procedures, reports, weather, airport and traffic context, exposure, recurrence, and the strength of the related barriers.

03 · Signal constellation

Recorded signals that may help explain the event.

calibrated airspeedtarget speedangle of attackengine thrust

Calibrated airspeed

Indicated airspeed corrected for instrument and position error, as provided by the aircraft data system.

Open parameter guide ↗% / ratio / aircraft-specific

Engine thrust

One or more recorded measures of commanded or produced propulsion; the correct signal depends on engine and aircraft type.

Open parameter guide ↗

04 · Validation and analysis

Questions before conclusions

Q1
Are calibrated airspeed, target speed, angle of attack valid, correctly decoded, time-aligned, and sampled well enough for this event?
Q2
What changed immediately before, during, and after the slow approach indication?
Q3
How do aircraft configuration, weather, airport geometry, automation state, and crew reports change the interpretation?
Q4
Which current flight manual, SOP, maintenance, or operator event definition controls the final conclusion?

05 · Connected intelligence briefs

Safety topics that broaden the event review.

Topic atlas1 operational connections

SAT-039 · Aircraft control & automation

Stall prevention and recovery

Maintaining angle-of-attack margin, recognizing stall cues, reducing angle of attack, managing thrust, and restoring a safe flight path.

Open topic profile ↗

Deep briefs3 detailed research guides

Flight Operations

Unstable Approach

Recognize when path, speed, configuration, power, or crew readiness has moved outside applicable stabilized-approach criteria.

Open topic brief ↗Flight Operations

Go-Around Decision and Execution

Treat the go-around as both a normal safety decision and a manoeuvre whose mode, thrust, configuration, path, and workload must be monitored.

Open topic brief ↗Flight Operations

Landing Performance

Connect approved landing-distance data with current wind, runway condition, aircraft state, touchdown point, and deceleration technique.

Open topic brief ↗

06 · Related official-source reading

12 useful starting points

Terminology and topic relationships select these links; the publisher source remains authoritative.

No copied report filesSearch all related records →

U.S. Federal Aviation AdministrationRelated safety-topic match

AC 91-79B — Aircraft Landing Performance and Runway Excursion Mitigation

This FAA circular brings together landing-performance planning, time-of-arrival assessment, RCAM information, and operational practices for reducing runway-excursion risk.

Open official source

U.S. National Transportation Safety BoardRelated safety-topic match

Safety Alert SA-077 — Stabilized Approaches Lead to Safe Landings

The NTSB alert highlights the need to establish and maintain a stabilized approach and to go around when an approach falls outside applicable criteria.

Open official source

Flight Safety FoundationRelated safety-topic match

Go-Around Decision-Making and Execution Project — Final Report

The Flight Safety Foundation project examines go-around policy compliance, decision biases, operational pressures, and the risks that also need to be managed during go-around execution.

Open official source

U.S. Federal Aviation AdministrationRelated safety-topic match

SAFO 21006 — SAFO 21006, Boeing Model 757 and 767 Airplane Inadvertent Pilot Activation of Go-Around Mode

Official U.S. Federal Aviation Administration material indexed for aviation safety. Open the publisher source for the complete document, scope, and current status.

Open official source

U.S. Federal Aviation AdministrationRelated safety-topic match

SAFO 15004 — SAFO 15004, Scenario-Based Go-Around Training

Official U.S. Federal Aviation Administration material indexed for human factors. Open the publisher source for the complete document, scope, and current status.

Open official source

U.S. Federal Aviation AdministrationRelated safety-topic match

SAFO 10005 — Go-Around Callout and Immediate Response

Official U.S. Federal Aviation Administration material indexed for aviation safety. Open the publisher source for the complete document, scope, and current status.

Open official source