540 to 550 Upgrade Path

An IFD550 will display pitch and roll attitude from the internal inertial unit displayed in either a conventional blue-over-brown ADI format, or in a synthetic vision format with 3-D terrain, obstacles, traffic, flight plan, etc.

In the synthetic vision view:

·         If the IFD is connected to a valid heading source, the attitude reference symbol will “point” at the current aircraft heading as provided by the external heading input. The total velocity vector (TVV) will “point” at the flight path angle. The 3D compass will display the current aircraft heading on a digital readout.

·         If the IFD is not connected to a valid heading source, the aircraft reference symbol will “point” at the current aircraft track as provided by the GPS. The 3D compass will display the current aircraft track from the GPS on a digital readout. There will be no display of the TVV.

The TVV is never shown in the conventional attitude indicator view.

The horizontal displacement of the TVV is computed as the angular difference between heading angle and track angle. Without a heading input, there is no computation to be performed and the TVV would be constrained to vertical displacement above/below the attitude reference symbol. While that provides some information, the TVV would serve merely as an angle of attack indicator, and was removed.

The acceptable heading sources for an IFD are:

Any device supplying ARINC 429 Label 320, Magnetic Heading (e.g. Aspen, G500/600, E1 PFD, EFIS40/50, GTX330 (data concentrator), Sandel EHSIs (3308, etc.), configuration items that support Magnetic Heading (in descending priority)

·         INS/IRU

·         EFIS

·         EFIS/Airdata

·         Honeywell EFIS  (e.g. Aspen PFD)

·         Garmin GDU (i.e. Garmin G500/600)

·         Sandel EHSI

·         Airdata/AHRS

·         Garmin GAD 42

·         Garmin GTX 330

·         Garmin GTX 330 w/ Traffic

·         Traffic Advisory

Devices configured Shadin-fadc or Shadin-adc that have a heading input.

Synchro (we have ~5 wires on the J5050 connector dedicated for this)

Stormscope (synchro into the stormscope, which sends it on in serial format)

We have no preference for which you use.  In my test airplane, I have:

Aspen PFD

Garmin G500

GTX330ES

TAS6XXA

TWX670

so it would be a bad day for me not to have heading input and therefore a TVV.