MOC VTOL.2555 Installation of recorders

This MOC is applicable to each recorder installed to comply with VTOL.2555.

(a)     General:

The recorder should have an ETSO authorisation against one of the following ETSOs or a later equivalent:

(1)     ETSO-C123b; or

(2)     ETSO-C124b; or

(3)     ETSO-2C197

(b)     Recorder installation:

The container of the recording medium should be located and mounted so as to minimise the probability of the container rupturing or the recording medium being destroyed as a result of impact with the Earth’s surface or of heat damage caused by a post-impact fire.

The structural provisions within the aircraft for the mounting of the recorder should be able to withstand the loads resulting from severe vibration (such as those resulting from rotor imbalance). In addition, the strength of the local attachments should be able to withstand the crash safety loads in CS 27.561(b)(3).

If the recorder has an erasure device or function, the installation must be designed to minimise the probability of inadvertent operation and actuation of the erasure device or function during crash impact.

(c)      Recorder identification:

A high proportion of the area of the outer surfaces of the container of the memory medium should be coloured bright orange.

The height, width and depth of the container of the memory medium must each be 4 cm (1.5 inches) or greater

(d)     Recorder characteristics:

The recorder should:

(1)     Permit quick downloading of the flight parameters without having to remove the recorder;

(2)     Be capable of retaining the flight parameters that are recorded during at least the preceding 5 hours and the audio recording during at least the preceding 2 hours;

(3)     Automatically start to record as early as possible after power-on and in any case prior to the aircraft being capable of moving under its own power;

(4)     Continue to record until the termination of the flight when the aircraft is no longer capable of moving under its own power;

(5)     If the recorder has a recording duration of less than 25 hours, have a means for the flight crew to stop the recording upon completion of the flight in such a way that re-enabling the recording is only possible by a dedicated manual action.

(e)     Flight Parameters and audio recording:

The recorder, or the combination of recorders installed to comply with VTOL.2555, should:

(1)     Record the flight parameters required to accurately determine the flight path, speed, attitude, engine power, operation and configuration of the VTOL capable aircraft. The minimum list of flight parameters to be recorded is provided in paragraphs (j) and (l). All recorded parameter values should be accurately time-stamped according to a common time reference and be recorded at a rate not below 4 Hz;

(2)     For aircraft with a minimum flight crew of two pilots, simultaneously record, on separate channels and with reference to a timescale:

(i)      The aural environment of the cockpit (area microphone;)

(ii)     Pilots’ headset audio, including but not limited to voice communications, audio signals for navigation aids, aural alerts.

(f)      Maintenance instructions:

(1)     When developing the ICA for the recorder systems, the applicant should address all the failures that may affect their correct functioning or the quality of the recorded information.

Note: ‘Recorder systems’ designates the recorders and their dedicated equipment (e.g. dedicated sensors or transducers, dedicated data busses, dedicated power source…).

(2)     Examples of failures (indicative and non-exhaustive list):

(i)      Loss of the recording function or of the acquisition function of the recorder;

(ii)     Failure of a means to facilitate the finding of the recording medium after an accident (e.g. an underwater locating device or an emergency locator transmitter attached to the recorder);

(iii)     Failure of a means to detect a crash impact (for the purpose of stopping the recording after a crash impact, or for the purpose of deploying the recorder if it is deployable);

(iv)     Failure of any power source dedicated to the recorder (e.g. dedicated battery);

(v)      Failure of the start-and-stop function;

(vi)     Failure of a sensor dedicated to the recorder system;

(vii)    For flight parameters recording, when any required parameter is missing, or is not correctly recorded;

(viii)   For audio recording (if applicable):

(ix)     Any required audio signal is missing, or is recorded with an audio quality that is rated ‘poor’ (refer to the example of audio quality rating provided in Section 9 of AMC 25.1459);

(x)      Failure of a transducer or amplifier dedicated to the recorder system (e.g. failure of the cockpit area microphone).

(g)     Data transmission & ground recording: [Reserved]

(h)     The following flight parameters should as a minimum be recorded with a recording resolution at least as high as specified in EUROCAE Documents ED-155 or ED-112:

(1)     Time

(2)     Altitude

(3)     Latitude

(4)     Longitude

(5)     Indicated airspeed or calibrated airspeed

(6)     Groundspeed

(7)     Outside Air Temperature (OAT)

(8)     Heading (magnetic or true)

(9)     Track

(10)    Vertical speed

(11)    Pitch attitude

(12)    Roll attitude

(13)    Longitudinal acceleration (body axis)

(14)    Normal acceleration

(15)    Lateral acceleration

(16)    Roll rate or Roll acceleration

(17)    Pitch rate or Pitch acceleration

(18)    Yaw rate or yaw acceleration

(19)    If electric engines are used:

(i)      Electric Engines: rotation speed of each rotor (in RPM)

(ii)     Electric Engines: health status of each electric engine controller

(iii)     Electric Engines: temperature of each electric engine

(iv)     Electric Engines: temperature of each electric engine controller

(v)      Electric Engines: measured electrical current for each electric engine

(vi)     For liquid cooled electric engines: pressure and temperature of the cooling liquid

(20)    Flight controls

(i)      Pilot input positions on all axis and corresponding flight control,

(ii)     Outputs (e.g. target RPM for each electric engine, flight surface positions, …)

(21)    Status of each flight control computer

(22)    Wings angle (if applicable)

(23)    Nacelles angles (if applicable)

(24)    Propeller pitch (for each variable pitch propeller)

(25)    Air-Ground status such as Weight on Wheels or equivalent parameter

(26)    Alerts (including master warning and master caution status)

(27)    Manual voice transmission keying (if voice communications are used)

(28)    For each battery used for propulsion and/or flight controls:

(i)      Health status, State Of Charge (SOC), voltage, temperature, current flow,

(ii)     if available:

(A)     State of Power (SOP); or

(B)     Calculated remaining flight time.

(29)    Health status of each electrical distribution unit (e.g. distribution units, converters) contributing to the propulsion and/or flight controls

(30)    Status of the battery management system (if any)

(31)    If combustion engine(s) are used:

(i)      Fuel parameters;

(ii)     Oil pressure and oil temperature;

(iii)     Parameters required to determine propulsive thrust or power delivered;

(iv)     Turbine RPM (if applicable);

(v)      FADEC health status (if applicable);

(vi)     Aircraft inputs used by the FADEC (if applicable);

(vii)    Any electrical current generation; and

(viii)   Any other parameter subject to a limitation

(i)      In addition, the following flight parameters should be recorded if they are used by the aircraft systems or are available for use by the pilot to operate the aircraft. They should be recorded with a recording resolution at least as high as specified in EUROCAE Documents ED-155 or ED-112:

(1)     Active AFCS mode

(2)     Radio altitude or terrain elevation

(3)     Current navigation source,

(4)     Vertical and lateral deviation with respect to current active navigation path

(5)     DME 1 & 2 distances

(6)     Drift angle

(7)     Wind speed

(8)     Wind direction

(9)     Landing gear position

(10)    Ice: ice detection, status of de-icing or anti-icing system

(11)    Electric Engine: vibration level

(12)    Traffic advisories or alerts, if installed (e.g. ADS-B IN, ACAS…)

(13)    Obstacle and terrain alerts, if installed (e.g. TAWS, …)

(j)      If the VTOL capable aircraft has datalink communication capabilities, the following should be recorded:

(1)     data link communication messages to and from the aircraft, including messages applying to the following applications:

(i)      data link initiation and termination,

(ii)     controller-pilot communication,

(iii)     addressed surveillance,

(iv)     flight information, including weather data (if required for operation),

(v)      aircraft broadcast surveillance,

(vi)     aircraft operational control data, and

(vii)    graphics.

(2)     information that enables correlation to any associated records related to data link communications and stored separately from the helicopter; and

(3)     information on the time and priority of data link communications messages, taking into account the system’s architecture.