Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Rejected Takeoff – Low Speed An event to detect that the takeoff roll has begun and the takeoff has been abandoned below a predetermined speed.
CAS, N1 CAS > x knots, CAS < x knots, N1 > x% for x seconds, followed by N1 < x% within 60 seconds Low end CAS should be greater than any anticipated taxi speed. 100 knots is generally accepted as the cutoff between high- and lowspeed aborts.
Rejected Takeoff – High Speed An event to detect that the takeoff roll has begun and the takeoff has been abandoned above a predetermined speed.
CAS, Gross Weight, N1 CAS > x knots, CAS < V1, N1 > x% for x seconds, followed by N1 < x% within 60 seconds If N1 is not an available parameter, V2 or Liftoff Speed may be used as the upper limit.
Liftoff Speed High An event to determine the relationship of the actual liftoff speed to V2.
Air/Ground Switch, Gross Weight, CAS Air/Ground = Ground, CAS > V2 + x knots for x seconds V2 is calculated based on Gross Weight.
Liftoff Speed Low An event to determine the relationship of the actual liftoff speed to V2.
Air/Ground Switch, Gross Weight, CAS Air Ground = Air, CAS < V2 – x knots for x seconds V2 is calculated based on Gross Weight.
Pitch High at Takeoff An event that measures pitch at takeoff in relation to the angle required to strike the tail of the aircraft.
Air/Ground Switch, Pitch Air/Ground = Ground, Pitch > x degrees Limits are based on the angle required for the tail cone to contact the ground with struts compressed.
Takeoff Climb Speed High An event to detect climb speed higher than desired during the Takeoff Phase of flight.
CAS, Gross Weight, HAT HAT > x feet, HAA < x feet, CAS > V2 + x knots Altitude ranges should be used to accommodate different desired climb speeds in those ranges. In certain ranges, the climb airspeed will be based on V2.
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Takeoff Climb Speed Low An event to detect climb speed lower than desired during the Takeoff Phase of flight.
CAS, Gross Weight, HAT HAT > x feet, HAA < x feet, CAS < V2 – x knots Altitude ranges should be used to accommodate different desired climb speeds in those ranges.
Early Flap Retraction An event to detect any flap movement from the takeoff position prior to reaching the altitude at which flap retraction should begin.
HAT, Flap Position HAT< x feet, Flap Position < Flap Position in the preceding sample
Excessive Bank Angle at Takeoff An event to detect when the bank angle exceeds the maximum allowable bank angle.
HAT, Roll HAT > x feet, HAT < x feet, Roll > x degrees for x seconds Altitude ranges should subdivide this event with different bank limitations in each range.
Turbulence – Flaps Extended An event to detect excessive G-forces prior to flap retraction.
Vertical Acceleration, Flap Position Flaps > 0, Vertical Acceleration > x g for x seconds
1.5 g is a generally accepted limit for this type of event.
This event can also occur during the Approach phase of flight.
Slow Initial Climb An event to detect a slower than normal climb to the clean-up altitude.
Air/Ground Switch, HAT Time > x seconds from Air/ Ground = Air to HAT = x feet HAT would be based on clean-up altitude.
Abnormal Flap Retraction An event to detect slow flap movement between any selected flap position and the previously selected flap position.
Flap Position, Flap Handle Position Time from Flap Handle Position = x degrees until Flap Position = x degrees > x seconds This event will also detect stuck flaps.
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Height Loss in Climb An event to detect an interruption in climb in which altitude is lost before the climb resumes.
HAT HAT < than x feet, HAT < HAT in preceding sample This event might benefit from subdivision in altitude ranges.
Climb Speed High An event to detect climb speed higher than 250 knots below 10,000 feet.
Altitude, CAS Altitude < 10,000 feet, CAS > 250 knots for x seconds
Flap Limit Altitude An event to detect when flaps are operated above the maximum allowable altitude for flap operation.
Altitude, Flaps Position Altitude > x feet, Flap Position > 0 degrees Altitude would correspond to the maximum operating altitude for flaps extended.
Turbulence – Flaps Up An event to detect excessive G-force while airborne, indicating an encounter with turbulent conditions.
Air/Ground Switch, Vertical Acceleration Air/Ground = Air, Vertical Acceleration > x g, Vertical Acceleration > -x g This event will measure turbulence from all sources (convective activity, clear air, or wake induced).
Vertical Acceleration limits of +1.5 g to – 0.5 g might be considered.
Holding/ Excess Radar Vectoring An event to detect excessive delays caused by ATC holding/radar vectoring.
Heading Cumulative Time > x, Heading = Heading + 359 degrees, Time < 600 seconds The start point for this event would occur after the first 360-degree turn and end 600 seconds after the last turn. The event would trigger when the cumulative time exceeds a userdefined value.
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Operating Ceiling Exceeded An event to detect operation of the aircraft above its certificated maximum operating altitude.
Altitude Altitude > x feet for x seconds
Landing Gear Down Speed Exceeded (Mach) The indicated mach number of the aircraft exceeds the maximum allowable mach for operation with the landing gear in the down position.
Mach, Landing Gear Position Landing Gear Position = Down, Mach > x mach number for x seconds Limiting mach number would be MLE.
MMO Exceeded An event to detect occurrences of the indicated mach number of the aircraft in excess of the maximum allowable mach number.
Mach Mach > x mach number for x seconds
VMO Exceeded An event to detect occurrences of the indicated airspeed of the aircraft in excess of the maximum allowable airspeed.
CAS CAS > x knots for x seconds
High Descent Rate An event that measures unusually high rates of descent.
Inertial Vertical Speed, HAT, Altitude Descent rate > x fpm for x seconds, HAT/Altitude > x, HAT/Altitude < x This event can be subdivided into altitude ranges to capture abnormal rates of descent that might be caused by different ATC facilities.
Excessive Speedbrake Usage An event that measures the amount of time the speedbrake is used during descent.
Speed Brake Handle, Air/Ground Switch Air/Ground = Air, Cumulative Time Speed Brake > 0 This event is useful in evaluating arrival procedures into specific airports.
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Approach Speed High An event to detect operation on approach that is in excess of its computed final approach speed.
Gross Weight, CAS, HAT, Flaps HAT > 1,000 feet, HAT < 3,000 feet, CAS > VFE – x knots HAT < 1,000 feet, CAS > VREF + x knots This event should be broken down into altitude bands.
Suggested breakdown would be HAT > 1,000 feet, HAT 500 – 1,000 feet, HAT 50 – 500 feet, HAT < 50 feet.
Speeds above 1,000 feet would reference a lookup table.
Approach Speed Low An event to detect operation on approach that is below its computed final approach speed.
Gross Weight, CAS, HAT HAT > 1,000 feet, CAS < flap maneuvering speed – x knots HAT < 1,000 feet, CAS < VREF – x knots Speeds above 1,000 feet would reference a lookup table.
Excessive Power Increase An event to detect an excessive power increase during final phase of approach.
HAT, N1 ∆ of N1 at 500 feet and N1 < 500 feet > x
Abnormal Configuration – Flaps/Speedbr ake An event to detect the simultaneous use of flaps and speedbrakes.
Speedbrake Handle, Flaps Speedbrake handle > 0, flaps > 0 This event would only be included if this type of operation were prohibited in the flight operations manual.
Abnormal Flap Extension An event to detect slow flap movement between any selected flap position and the previously selected flap position.
Flap Position, Flap Handle Position Time from Flap Handle Position = x degrees until Flap Position = x degrees > x seconds This event will also detect stuck flaps.
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Landing Gear Down Speed Exceeded (IAS) An event to detect when the indicated airspeed of the aircraft exceeds the maximum allowable airspeed for operation with the landing gear in the down position.
Landing Gear Position, CAS Landing Gear = Down, CAS > x knots
Late Landing Flaps An event to detect flap movement to the landing flap position below a predetermined altitude.
HAT, Flap Handle Position, Air/Ground Switch Air/Ground = Air, HAT < x feet, Flap Handle Position at x feet HAT < Flap Handle Position at touchdown This event is slightly different from Late Landing Configuration in that it detects flap movement below a set altitude rather than a flap setting.
Low Power on Approach An event to detect aircraft engines not spooled or the power reduced to an unspooled condition below a predetermined altitude.
Air/Ground Switch, HAT, N1 Air/Ground = Air, HAT < x feet, N1 < x %
Landing Gear Operation An event to detect when the indicated airspeed of the aircraft exceeds the maximum allowable airspeed for operation of the landing gear in transit.
Landing Gear Warning, CAS Landing Gear Warning (in transit) = On, CAS > x knots If the operating limitation is different for landing gear extension and retraction, separate events will need to be created for each limitation.
Operation Left of Localizer Centerline An event to detect deviation left of localizer centerline.
Localizer Deviation Left, HAT Localizer Deviation > x dots, HAT > x feet
Operation Right of Localizer Centerline An event to detect deviation right of localizer centerline.
Localizer Deviation Right, HAT Localizer Deviation > x dots, HAT > x feet
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Operation Above Glideslope An event to detect deviation above glideslope.
Glide Slope Deviation High, HAT Glide Slope > x dots, HAT < x feet
Operation Below Glideslope An event to detect deviation below glideslope.
Glide Slope Deviation Low, HAT Glide Slope > x dots, HAT < x feet
Descent Below MDA An event to detect descent below MDA (followed by a climb back to MDA) on nonprecision approaches.
HAT, Altitude HAT < 1,000 feet, Altitude > Altitude in preceding sample + x feet
Flap Limiting Speed An event to detect flap operation at a speed that exceeds the maximum placarded airspeed.
Flap Position, CAS Flap Position = x, CAS > x knots for x seconds This event will be constructed with a different speed limit for each flap setting through the use of a lookup table. It will also detect speed exceedances during retraction in the Takeoff phase of flight.
Go Around An event to detect that the aircraft has begun its descent for landing, discontinues that descent, and does not land from that approach.
HAT, Altitude, N1 HAT < 2,000 feet, HAT > 1 foot, Altitude < preceding Altitude sample for 10 seconds, N1 > 98%, Altitude > any preceding Altitude sample in previous 60 seconds + 300 feet
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
ATC Go Around An event to detect a go-around event in which no other events are triggered, such as approach instability, indicating the go around was directed by ATC.
HAT, Altitude, N1, Localizer Deviation, Glide Slope Deviation, CAS HAT < 2,000 feet, HAT > 1 foot, N1 > 98%, Altitude > any preceding Altitude sample in previous 60 seconds + 300 feet, Localizer Deviation < x dots, Glide Slope Deviation < x dots, CAS = VREF ± x knots
Late Landing Configuration An event to detect that the aircraft is not configured with landing flaps and landing gear in the down and locked position at 500 feet HAT.
HAT, Landing Gear Position, Flap Position HAT < 500 feet, Landing Gear Warning = On, Flap Position < x flaps
Tire Limiting Speed An event to detect if the tire limiting speed is exceeded.
Air/Ground Switch, CAS Air/Ground = Ground, CAS > x knots
Pitch High – Landing An event that measures pitch at landing in relation to the angle required to strike the tail of the aircraft.
Air/Ground Switch, Pitch Air/Ground = Ground, Pitch > x degrees from 6 seconds before to 15 seconds after touchdown Limits are based on the angle required for the tail cone to contact the ground with struts compressed.
Pitch Low – Landing An event that measures pitch attitude where the aircraft is in a nose down attitude that might result in an initial nose-gear touchdown or threepoint landing.
Air/Ground Switch, Pitch Air Ground = Ground, Pitch < x degrees from 3 seconds before to 1 second after touchdown
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Landing in a Crab An event to detect failure to align aircraft with the runway at touchdown.
Heading, CAS ∆ Heading at Touchdown vs. Average Heading until CAS = 60 knots
Hard Landing An event that measures excessive G- force at touchdown, indicating a hard landing.
Air/Ground Switch, Vertical Acceleration Air/Ground = Ground, Vertical Acceleration > x G
Bounced Landing An event that measures excessive G- force at touchdown followed by a second excessive G-force, indicating a bounced, hard landing.
Air Ground Switch, Vertical Acceleration Air/Ground = Ground, Vertical Acceleration > x G, followed by second Vertical Acceleration > x G within 20 seconds of first touchdown
Excessive Brake Usage An event to detect higher-than-normal brake application.
Brake Pressure Sum of Brake Pressure readings (one per second) from Touchdown to Runway Turnoff/1000.
Resulting index number > x A routine operational measurement (ROM) would be helpful to determine normal braking at a given airport.
Thrust Reverser Stowed An event that measures the speed at which the thrust reverser is stowed during landing rollout.
CAS, Thrust Reverser Deploy Thrust Reverser = On for 5 seconds before Thrust Reverser = Off, CAS > x knots
Overweight Landing An event to detect landings made in excess of the maximum gross landing weight.
Air/Ground Switch, Gross Weight Air/Ground from Air to Ground + 20 seconds, Gross weight > x pounds
Appendix A
Event Name Event Description Parameters and Basic Event Definition Notes
Abnormal/ Incorrect Landing Flaps An event to detect that the aircraft touched down with flaps in a position less than the minimum expected landing flap setting.
Air/Ground Switch, Flap Position, Air/Ground from Air to Ground + 5 seconds, Flaps < x degrees Will need to be customized for the recommendations in the flight manual.
Runway/Taxi way Rough An event that measures excessive G- force on the ground, indicating defects in runway/taxiway surfaces.
Air/Ground Switch, Vertical Acceleration, CAS Air/Ground = Ground, CAS < 100 knots, Vertical Acceleration >1.3 g
Stick Shaker Operation An event to detect stick shaker operation.
Stick Shaker Stick Shaker + On (L or R)
GPWS Warning An event to detect when a GPWS warning is triggered.
GPWS GPWS = On This event should be subdivided for each of the different warning modes of the GPWS.
Engine Failure An event to detect inflight engine failure/shutdown.
Air/Ground Switch, Fuel Flow, Oil Pressure, EGT Air/Ground = Air, Oil Pressure < x psi, Fuel Flow < x pph, EGT < x degrees
TCAS Advisory An event to detect any TCAS advisory triggered.
TCAS Advisory (Up or Down) TCAS Advisory = On This event should be separated for TCAS Traffic Advisories (TAs) and Resolution Advisories (RAs).
Engine Reverse at Low Speed An event to detect use of engine reverse at low speed that can result in engine overtemps and/or FOD ingestion.
Thrust Reverser, N1, CAS Thrust Reverser = On, CAS < x knots, N1 > x% for x seconds
Appendix A
APPENDIX III. GLOSSARY
GLOSSARY Term Definition ACARS Aircraft Communications Addressing and Reporting System. ACARS is a VHF air/ground data link that uses nearly 600 VHF frequency locations throughout North and Central America, Hawaii, the Caribbean, and several U.S. territories. It relays Aircraft Operational Control (AOC), Airline Administrative Control (AAC), and Air Traffic Control (ATC) messages between ground-based organizations and the cockpit.
ACMS Aircraft Condition Monitoring System. An airborne unit that can create reports such as long-term trend data and aircraft/engine monitoring.
ACMS is mainly used for maintenance applications.
Aggregate Data Detailed data grouped according to some criterion and combined using mathematical or statistical methods (e.g., sum, count, average, standard deviation).
Air Carrier An organization that undertakes -- either directly or by lease or some other arrangement -- to engage in air transportation.
ARINC Aeronautical Radio Incorporated. The ARINC organization is the technical, publishing, and administrative support arm of the Airlines Electronic Engineering Committee (AEEC) groups. AEEC standards define avionics form, fit, function, and interfaces.
ATC Air Traffic Control. A service operated by appropriate authority to promote the safe, orderly, and expeditious flow of air traffic.
COTS Commercial-Off-the-Shelf. Products, components, or software that are readily available through normal commercial channels, as opposed to custom-built units that would achieve the same functionality.
DAR Digital ACMS Recorder. See ACMS.
Data Frame A data map. See LFL.
De-identified Data Data from which any identifying element that could be used to associate them with a particular flight, date, or flightcrew has been removed.
Appendix A
GLOSSARY Term Definition DFDAU Digital Flight Data Acquisition Unit. A device that acquires aircraft data via a digital data bus and analog inputs, and formats that information for output to the flight data recorder in accordance with requirements of regulatory agencies. In addition to the mandatory functions, many DFDAUs have a second processor and memory module that enables them to perform additional Aircraft Condition Monitoring System (ACMS) functions/reports. The DFDAU can provide data and pre-defined reports to the cockpit printer, or a display for the flightcrew, or directly to Aircraft Communications Addressing and Reporting System (ACARS) for transmittal to a ground station, or to a Quick Access Recorder (QAR) for recording/storage of raw flight data.
DFDMU Digital Flight Data Management Unit. A unit that performs the same data conversion functions as the DFDAU and has the added capability to process data onboard the aircraft. Additionally, this unit has a powerful data processor designed to perform in-flight airframe/engine and flight performance monitoring and analysis. Some DFDMUs have ground data link and ground collision avoidance systems incorporated into the units.
DFDR Digital Flight Data Recorder. A digital device that records pertinent parameters and technical information about a flight. At a minimum, it records those parameters required by the governing regulatory agency, but may record a much higher number of parameters. A DFDR is designed to withstand the forces of a crash so that information recorded by it may be used to reconstruct the circumstances leading up to the accident.
DMU Data Management Unit. A unit that performs the same data conversion functions as a Flight Data Acquisition Unit (FDAU) with the added capability to process data onboard the aircraft. Additionally, this unit has a powerful data processor designed to perform in-flight airframe/engine and flight performance monitoring and analysis. Some DMUs have ground data link and ground collision avoidance systems incorporated into the unit.
EGT Exceedance Guidance Team. See FMT.
EMT Event Monitoring Team. See FMT.
Event An occurrence or condition in which pre-determined limits of aircraft parameters have been exceeded. Events represent the conditions to be tracked and monitored during various phases of flight and are based on sensory data parameters available on a specific aircraft fleet. Events may be categorized at different severity levels based on the degree to which the associated limits were exceeded. Most FOQA trend analysis is based on event monitoring and tracking.