Why some aircraft have a Noise Certificate—and others legitimately don’t
In just a few weeks, almost 30 aircraft from across Europe will depart on the PrivatePilot.lu Georgia Expedition 2026.
Preparing an international expedition isn’t just about route planning and fuel stops.
It also means collecting aircraft documentation for dozens of airports in eight different countries.
Registration certificates.
Insurance.
Radio licences.
Airworthiness documents.
And sometimes…
Noise Certificates.
That simple request led to an interesting discussion among our participating pilots.
Some could send the document immediately.
Others—despite flying brand-new, state-of-the-art aircraft—simply couldn’t.
Not because the document was missing.
Because it doesn’t exist.
Coincidentally, only days later, EASA announced ENCODE (EASA’s Noise Compliance Demonstration Evaluator), a new tool that standardises how aircraft noise is assessed during certification.
The timing couldn’t have been better.
Because it also helps explain one of the biggest misconceptions in General Aviation.
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First things first: what is a Noise Certificate?
A Noise Certificate is not a document stating that an aircraft is quiet.
Nor is it something measured during the annual inspection.
It is an official document confirming that the aircraft type has successfully completed the international noise certification process defined in ICAO Annex 16.
Only aircraft that have gone through that certification process can receive one.
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Why do certified aircraft have one?
Aircraft such as the:
• Piper PA-28
• Cessna 172
• Diamond DA40
• Cirrus SR22
were all developed under an EASA (or equivalent) Type Certificate.
During certification, manufacturers must prove that the aircraft complies with numerous requirements, including aircraft noise.
Special flight tests are flown under tightly controlled conditions.
EASA’s newly released ENCODE tool demonstrates just how complex those tests actually are.
The measured noise is corrected for:
• aircraft height;
• climb speed;
• atmospheric pressure;
• temperature;
• humidity;
• engine power;
• propeller tip Mach number;
• atmospheric absorption;
• and several other variables.
Only after all these corrections is the official certified noise level determined.
That certified value becomes part of the aircraft’s approved type design.
Each individual aircraft can therefore receive an official Noise Certificate.
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So why don’t many modern aircraft have one?
Because they belong to a completely different certification system.
Many aircraft participating in our Georgia Expedition are nationally regulated aircraft, including French ULMs and other European microlights.
These aircraft are perfectly legal.
They comply with their own national certification requirements.
But they were never required to undergo ICAO Annex 16 noise certification.
No ICAO noise certification means…
…no ICAO Noise Certificate.
That does not mean they are louder.
It simply means they followed a different regulatory pathway.
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The irony
This is where many people get confused.
Imagine two aircraft parked next to each other.
One is a forty-year-old certified trainer powered by a Lycoming engine.
The other is a modern carbon-fibre aircraft with a fuel-injected Rotax engine and a highly efficient composite constant-speed propeller.
Ask almost any pilot which one is quieter.
Most would point to the modern aircraft.
Yet the older aircraft almost certainly has an official Noise Certificate.
The modern aircraft may not.
Not because it is noisier.
But because only one of them was required to complete ICAO noise certification.
The certificate reflects the certification route, not a comparison between two individual aircraft.
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Why this matters during international flying
While preparing our Georgia Expedition, this wasn’t a hypothetical question.
Both the Georgian and Turkish national aviation authorities requested the Noise Certificate as part of our overfly permit applications.
For our EASA type-certificated aircraft, that was a simple attachment.
For our ULM and microlight pilots, it meant explaining—in writing, to a foreign CAA—that the aircraft is nationally regulated, was never required to undergo ICAO Annex 16 noise certification, and therefore has no such certificate to provide.
Once that distinction is understood, the permit process moves forward without further delay.
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Why EASA’s announcement matters
Most private pilots will never open ENCODE.
Manufacturers and certification engineers will.
But by making both the tool and its methodology publicly available, EASA has also given ordinary pilots a fascinating insight into how aircraft noise certification really works.
More importantly, it reminds us that there is a crucial difference between being a quiet aircraft and having a Noise Certificate.
Those are not the same thing.
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Final approach
When our expedition departs Luxembourg for Georgia later this summer, nearly thirty aircraft will fly together towards the Caucasus.
Some will carry an official ICAO Noise Certificate.
Some legitimately never will.
Yet all of them comply with the regulations that apply to them.
And perhaps that’s the real lesson behind EASA’s latest announcement:
A Noise Certificate is not a badge of how quiet an aircraft is. It is evidence of the certification framework under which it was approved.
Understanding that distinction helps pilots, airport operators and authorities speak the same language—and avoids a lot of unnecessary confusion before the propeller even starts turning.
