✈️ ICAO Annex 16 – Volume II: Aircraft Engine Emissions Title: Environmental Protection – Aircraft Engine Emissions Objective: To limit and control emissions from aircraft engines that impact local air quality and contribute to climate change. 🔹 Key Components 1. Applicable Emissions Focuses on emissions from turbojet and turbofan engines with thrust > 26.7 kN, specifically: ▪️Nitrogen oxides (NOₓ) ▪️Hydrocarbons (HC) ▪️Carbon monoxide (CO) ▪️Smoke and particulate matter (PM) 2. Certification Standards Emissions are tested during four operating modes: ▪️Idle ▪️Approach ▪️Climb-out ▪️Takeoff Results are compared to ICAO’s regulatory emission limits. 3. Testing Procedures ▪️Engine emissions are measured under controlled conditions (test benches). Standardized using: ▪️Landing and Takeoff (LTO) Cycle: Represents emissions near airports (up to ~3,000 ft). ▪️Prescribed engine settings, fuel flow, and ambient conditions. 4. Smoke & Particulates ▪️Limits on visible smoke are enforced for aesthetic and pollution concerns. ▪️Newer standards also address non-volatile particulate matter (nvPM). 5. Applicability ▪️Applies to new engine types and sometimes retroactively to older models under recertification. ▪️Manufacturers must demonstrate compliance for each engine model. 🌍 Environmental Impact ☢️Pollutant ▶️Effect ☢️NOₓ ▶️Contributes to ozone formation & acid rain ☢️CO ▶️Toxic gas, harmful to health ☢️HC▶️ Contributes to smog and ozone ☢️Smoke/nvPM ▶️Reduces visibility, harms respiratory health