What is the Variable Exhaust Nozzle (VEN)?

What is the Variable Exhaust Nozzle (VEN)?

• A. A fixed nozzle with no moving parts.
• B. A digital sensor for nozzle temperature.
• C. A cam and link-positioned hinged-flap, conversion-divergent nozzle mounted to the aft end of the afterburner case.
• D. An electronic control module for engine start.

Answer: (C)

The key idea is how the nozzle geometry is varied to optimize engine performance. The Variable Exhaust Nozzle is a mechanically actuated convergent-divergent nozzle that is mounted to the aft end of the afterburner case. It uses a cam-and-link arrangement to move hinged flaps, allowing the nozzle exit area to change. By adjusting these flaps, the nozzle can transition between smaller and larger openings to control the exhaust expansion, which helps maintain efficient pressure recovery and thrust across different engine states and afterburner conditions. That combination of moving parts, location, and function distinguishes it from a fixed nozzle, a temperature sensor, or an electronic start module.

The key idea is how the nozzle geometry is varied to optimize engine performance. The Variable Exhaust Nozzle is a mechanically actuated convergent-divergent nozzle that is mounted to the aft end of the afterburner case. It uses a cam-and-link arrangement to move hinged flaps, allowing the nozzle exit area to change. By adjusting these flaps, the nozzle can transition between smaller and larger openings to control the exhaust expansion, which helps maintain efficient pressure recovery and thrust across different engine states and afterburner conditions. That combination of moving parts, location, and function distinguishes it from a fixed nozzle, a temperature sensor, or an electronic start module.