Noise Abatement

Noise Abatement

Aircraft noise comes from three sources — operational noise (engine), exhaust noise, and propeller noise — and affects every powered aircraft. Noise abatement is required by law (ICAO Annex 16, EU regulations) and by ethics (residents).

Source: ICAO Annex 16 Volume I Environmental Protection — Aircraft Noise; ICAO Doc 8168 PANS-OPS Vol I, Part V — Noise Abatement Procedures; FAA AC 91-53A Noise Abatement Departure Profile (NADP); EASA SERA and national AIP noise rules.

Noise sources in light aircraft

→ Reducing RPM is the most effective lever for light powered flight, because exhaust and propeller noise dominate.

Noise abatement on departure

General principles

• Use full runway length: start take-off roll at the beginning, then full power for maximum climb over residents.
• Once minimum safe altitude is reached (typ. 500 ft AGL above obstacles) or obstacles cleared: reduce power to cruise-climb power.
• Straight ahead until safe altitude — no turns at low altitude over inhabited areas.
• After lift-off, fly the speed for optimum altitude gain (Vy) — quick separation from the ground.
• Follow established departure routes ("noise abatement routes" published in AIP/VAC) when available.
• Circumnavigate inhabited areas when departing nearby, and cross only at sufficient altitude if unavoidable.

Reduction during take-off (essentials)

1. Use the full runway (start the take-off roll at the threshold).
2. Set full power for take-off.
3. Vy for best altitude gain.
4. Climb straight without turns over inhabited areas.
5. Reduce power as soon as minimum safe altitude is reached or obstacles are passed.

Noise abatement en-route

• Sufficient altitude above inhabited areas — operationally feasible 2000 ft AGL or more (varies nationally).
• Low RPM settings (where POH and fuel consumption permit): directly lower propeller and exhaust noise.
• Smooth flight: turns and power changes produce audible noise variations on the ground.

Noise abatement on approach

• High approach (steeper-than-normal glide path), as long as possible — delays ground noise.
• Minimum power setting: idle as high as possible, then power only to stabilise.
• Late descent initiation — stay at altitude as long as possible to reduce ground noise.
• Late configuration: gear and flaps extended only in due time — early flaps require higher power.
• Follow established arrival routes in the AIP.

Descent choreography (example)

• High and dry to start — stay at altitude as long as possible.
• At TOD ("Top of Descent"): reduce power to just enough for a stable descent.
• Flaps / gear as late as possible — typically only once established on final.

Noise abatement vs safety — conflicts

Noise abatement must never compromise safety:

• If obstacle clearance requires steeper climb: Vy / Vx, full power — noise is secondary.
• If weather makes a stabilised approach difficult: do not delay configuration at the cost of stability.
• Pilot in Command is the final authority; safety > noise abatement.

Operational notes

• Noise NOTAMs (Germany: BAF Nachrichten für Luftfahrer) are binding when published.
• Noise sensitivity zones marked on VAC charts (often dashed circles around airfields).
• Resident complaints are frequent — a main driver of airfield closures.
• Glider and ULM aerodromes are especially sensitive.