Application Note...

Air Data Test Set (ADTS)

Application:

Production testing and repair of altitude gauge, air speed indicators, air data computers and auto pilot controllers.

Challenge:

Customer wanted a high-speed air data controller that could operate and collect data over an IEEE-488 interface. All of the units would have to operate using a common pressure and vacuum source. The auto pilot controller test required that the ADTS operate at 50 feet per minute altitude rate.

Solution:

The standard Mensor Model 8201 ADTS meets all of the requirements except the 50 feet per minute altitude rate requirement. Fifty feet per minute is an extremely low pressure rate of change, especially at high altitudes. To meet this, the regulator had to be custom balanced. To achieve this balance, the flow characteristics of the supply and exhaust regulation systems were match. At the time the initial unit was sold, this was a tedious trial and error procedure. Subsequently, this procedure has been simplified and is now achieved electronically in the circuits that energize each reed valve.