Tuesday, September 7, 2010

Avionics Bending: SFENA Attitude Director Indicator (ADI) (Analysis)

Today's posting is on a set of beautiful Attitude Director Indicators. The ones that I selected for the project are actually not common on the L-1011, but they flew on an Airbus A300. Which from a time period point of view, overlaps with the L-1011. The devices are made by SFENA, France and the part number is N32aAM with an original manufacturing date of January 1982.

The ADI as indicators for:
  • Aircraft Attitude
  • Bank Angle
  • Turn Coordination
  • Glide Slope Deviation
  • Localizer Deviation
  • Fast/Slow on Approach
  • Flight Director Pitch
  • Flight Director Roll
  • Decision Height
  • Attention

To see the ADI in check this blog posting: SFENA ADI Working with XPlane

The next few pictures show the unit without the back cover. The instrument is really beautifully engineered. Just as with many other SFENA devices, the entire instrument is built very modular. The ball representing the gyro has two motors: (a) one for pitch inside the globe and (b) another for roll on the backside of the C-shaped mount.

Both the roll and the pitch motors are supported by a 400Hz resolver.

The two flight director bars in action.

1) Flight Director directs a turn to the left.

2) Flight Director directs a climbing right turn.