The AIU is presently approved on the  Gulfstream GII/GIIB aircraft and the Boeing 727-100 aircraft using the Honeywell/Sperry FZ-500 flight director system.

Reference the Manuals page for installation and information manuals.

Instructions for Continued Airworthiness

END COCKPIT CONFUSION

AES has developed the AIU as an answer to an old problem -- Non-integrated flight directors.

In the past, when an older generation aircraft such as B727s or GIIs were upgraded with new flight directors and an FMS, the full benefit of these upgrades could never be achieved due to lack of integration with existing autopilot.  Now that problem is solved by the AIU.

The AIU will couple all of the selectable modes of the flight director to the autopilot.  This means that once the autopilot is engaged, one selection on the flight director will do it all!  All "V" bar commands are coordinated with the autopilot so it looks and feels just like the new, expensive digital autopilots.  The turn knob and pitch wheel functions on your existing autopilot controller will continue to operate the same as always, but separate autopilot mode selections will no longer be needed.

Although the AIU was developed to allow aircraft owners to gain full benefit from their new upgrades, it can also be added to existing FZ-500 flight director systems to provide the same beneficial results.

Above diagram is for reference only. Reference the Manuals page for installation and information manuals.

OPERATIONAL SUMMARY: 

1. Autopilot engaged with no flight director modes selected: normal A/P pitch & turn knob operation.
   
   
2. Selection of valid FD lateral mode enables AIU to process roll commands from FZ-500 and route to A/P heading channel input.
   
   
3. Selection of valid FD pitch modes enables AIU to process pitch commands from FZ-500 and route to A/P V/S command input.
   
   
4. Moving A/P pitch wheel clears ALT, VS, IAS, MACH, APP CAPT, ALT PRESEL CAPT, does not clear ALT PRESEL ARM, or APP ARM.
   
   
5. Moving A/P turn knob clears all lateral modes.
   
   
6. During AIU coupled operations, the A/P pitch mode selector knob and A/P NAV mode selector knobs are disabled, as well as the A/P HDG select switch/solenoid.
   
   
7. In the event of AIU failure, the unit allows control to return to basic A/P operation. The "AIU FAIL" annunciator will light.  Pull the AIU DC circuit breaker to disable the unit.  All A/P controls & modes will operate normally as a backup mode.
   
   
8. Single system operation illustrated: "coupled-1 coupled-2" operation, is operator's choice using switched signals from #2 FZ-500 with coupled-2 relay logic.