What this profile covers
Risk control when dispatching with permitted inoperative equipment, including combinations, intervals, procedures, placards, and operational context.
Why it matters
System events can alter aircraft capability, redundancy, workload, procedures, and the reliability of other safety barriers. For deferred defect management, useful analysis connects the immediate event with exposure, defenses, recurrence, and the wider operating system rather than treating one observation as a final conclusion.
System degradation, warning integrity, technical condition, dispatch decisions, and continued airworthiness.
Understand the subject before interpreting a signal.
In plain language, this profile examines risk control when dispatching with permitted inoperative equipment, including combinations, intervals, procedures, placards, and operational context.
Build a multi-source picture
- Warnings and system parameters
- Technical logs and maintenance history
- Crew reports and operational response
- Engineering inspection, test, and component evidence
Timing, relationships, and recurrence
Relevant recorded context may include normal acceleration, radio altitude, vertical speed, pitch attitude, engine thrust. Use validated mappings and examine signal relationships over the applicable flight phase.
Do not turn an observation into a conclusion
Flight data can reconstruct symptoms and response but does not replace troubleshooting, approved maintenance data, inspection, or an engineering airworthiness decision.
Keep controlling material visible
Apply the current approved manuals, procedures, authority requirements, investigation evidence, and validated organizational definitions for any operational decision.
Normal acceleration
Acceleration measured broadly along the aircraft's vertical body axis; its touchdown peak can help characterize a landing load when interpreted with other signals.
Open parameter guide ↗ftRadio altitude
Height derived from radio altimetry, normally representing the distance from the aircraft to terrain directly below within the system's operating range.
Open parameter guide ↗ft/min or m/sVertical speed
The aircraft's vertical rate. Different recorded sources and smoothing can produce materially different values, especially during flare and touchdown.
Open parameter guide ↗degPitch attitude
Aircraft body attitude above or below the local horizontal reference.
Open parameter guide ↗% / ratio / aircraft-specificEngine thrust
One or more recorded measures of commanded or produced propulsion; the correct signal depends on engine and aircraft type.
Open parameter guide ↗discreteLanding gear status
Command, position, lock, and ground-sensing states associated with the landing gear; these are separate signals with different meanings.
Open parameter guide ↗From a broad topic to a defensible safety review.
Define
State what deferred defect management means for the aircraft, operation, authority, and organization in scope.
Verify
Confirm the provenance, quality, timing, units, completeness, and limitations of every data source used.
Describe
Reconstruct what happened and quantify relevant exposure before discussing causes or corrective action.
Corroborate
Compare flight data with reports, operational context, technical evidence, and authoritative source material.
Test barriers
Identify which preventive, recovery, and consequence-mitigation controls should have worked and how their performance can be measured.
Assure
Assign proportionate action and verify whether the control and safety performance improve without harmful unintended effects.
Questions before conclusions
- Q1
How is deferred defect management defined for the aircraft, operation, authority, and organization being reviewed?
- Q2
Which precursors, recorded signals, reports, and external data would confirm the event and describe its context?
- Q3
Which preventive, recovery, and consequence-reduction barriers should work, and where could they weaken?
- Q4
What does recurrence, exposure, severity potential, or change over time show before choosing a safety action?
4 connected event profiles
These are terminology and family connections for exploration—not claims that FDM alone can determine the topic.
Bounced landing
Recorded air/ground transitions and vertical motion indicate the aircraft became airborne again after initial touchdown.
Open FDM profile ↗FDM-119 · Systems & warningsAnti-ice configuration mismatch
Anti-ice or de-ice system state differs from the validated environmental, phase, or procedure context.
Open FDM profile ↗FDM-121 · Cabin, cargo & evacuationCargo smoke warning
A cargo-compartment smoke or fire warning is recorded during ground or flight operation.
Open FDM profile ↗FDM-122 · Cabin, cargo & evacuationCabin or avionics smoke warning
Recorded smoke, ventilation, avionics, or air-quality warning data indicate a possible occupied-area or equipment-bay smoke event.
Open FDM profile ↗Go deeper into the closest ASIP research guides.
Hard Landing
A structured guide to recognizing, reporting, analyzing, and responding to a suspected touchdown load exceedance without confusing passenger perception with an engineering determination.
Open intelligence brief ↗Aircraft SystemsFlight-Deck Automation
Use mode awareness, active monitoring, and aircraft-response verification to keep automation aligned with crew intent.
Open intelligence brief ↗Aircraft SystemsEngine Failure and Thrust Loss
Separate commanded thrust, actual engine response, system effects, and crew management across partial, asymmetric, and complete thrust-loss events.
Open intelligence brief ↗Aircraft SystemsFire and Smoke
View fire safety as detection, containment, checklist action, diversion, evacuation, and rescue barriers.
Open intelligence brief ↗12 useful starting points
Original ASIP summaries lead to publisher pages. ASIP does not copy or host the reports.
Annex 19 — Safety Management, Third Edition
Annex 19 consolidates ICAO safety-management provisions, including State safety responsibilities, SMS, safety-data collection and processing, and the protection and sharing of safety information.
Open official sourceAnnual Safety Review 2025
EASA's review uses occurrence and accident information to describe performance across aviation domains and to support the European safety-risk-management process.
Open official sourceStatistical Summary of Commercial Jet Airplane Accidents, 1959–2024
Boeing's 56th annual statistical summary organizes commercial-jet accident data using stated definitions and the CAST/ICAO occurrence taxonomy.
Open official sourceIATA Annual Safety Report — 2024
IATA's 61st annual report provides an interactive, method-defined view of commercial aviation accident performance and contributing-factor classifications.
Open official sourceAC 120-92D — Safety Management Systems for Aviation Service Providers
FAA guidance explains performance-based, scalable approaches to integrating safety policy, risk management, assurance, and promotion into aviation organizations.
Open official sourceAC 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 sourceSafety 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 sourceHigh Load Event Reporting
The Airbus Safety First article explains why a pilot report remains central after a suspected high-load event and how recorded reports and analysis tools can support the applicable maintenance process.
Open official sourceSafety Management Manual (Doc 9859), Fourth Edition
ICAO's fourth-edition manual explains how safety data, risk management, assurance, culture, and governance work together in State and service-provider safety management.
Open official sourceGo-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 sourceCAP 739 — Flight Data Monitoring, Second Edition
CAP 739 presents FDM as the systematic, proactive use of routine digital flight data within a non-punitive, just safety culture.
Open official sourceAC 120-82 — Flight Operational Quality Assurance
Active FAA guidance describes one acceptable way to establish a voluntary FOQA programme using de-identified aggregate flight data to identify and reduce operational risk.
Open official sourceCommon Taxonomy Team
International work on common aviation occurrence categories and definitions for consistent reporting and analysis.
Open referenceSafety Risk Management
European safety-risk process connecting data, safety issues, risk portfolios, priorities, and safety action.
Open referenceAnnual programmes and reports
Annual safety reviews and risk portfolios used to identify key risk areas, safety issues, and emerging issues.
Open referenceEuropean Plan for Aviation Safety 2025
A broad evidence-based portfolio showing the scale and connected nature of current aviation safety issues.
Open referenceOperational issues index
A practical discovery index for operational safety subjects; official authority and manufacturer sources remain controlling where applicable.
Open reference