FAA Powerplant Written Practice Test

What is a key characteristic of Full Authority Digital Engine Control (FADEC)?

1. A It requires constant manual adjustment

2. B It can switch between manual and automatic modes

3. C It has no hydro mechanical fuel control backup

4. D It operates solely on pneumatic signals

The correct answer is: C It has no hydro mechanical fuel control backup

A key characteristic of Full Authority Digital Engine Control (FADEC) is that it has no hydro-mechanical fuel control backup. FADEC is an advanced control system that integrates all engine control functions into a single, digital electronic system. This means that it handles fuel flow, ignition timing, and other critical engine parameters without relying on traditional mechanical components. The absence of a hydro-mechanical backup simplifies the system and enhances reliability, as it can respond more quickly and accurately to changing operating conditions without the potential complications that come with additional mechanical systems. In contrast to other systems that may have mechanical backups or manual adjustments, FADEC operates with full authority and autonomy, allowing for optimized engine performance and efficiency without needing manual intervention or secondary mechanical systems.