7 minute read · Updated for ICAO Doc 9835, 2nd edition
How ICAO English scoring works
The six criteria, the six levels, and the one rule most pilots get wrong. Read this before you take the test — or before you pick a tool to prepare with.
The short version
ICAO sets the rules for how pilots are tested on aviation English. The official document is Doc 9835. It says examiners score you on six things — pronunciation, structure, vocabulary, fluency, comprehension, and interactions — using a six-level scale. Level 4 is the minimum required to fly internationally.
Most preparation tools test you on one of these at a time. Examiners don’t. They watch all six at once, every time you open your mouth. That gap — between sounding ready and being ready — is what this page is about.
The six criteria, explained
These six are the entire scoring framework. They aren’t separate skills you can drill in isolation — they’re six lenses on the same conversation. Here is what each one looks for.
Pronunciation
Can you be understood?
You can have an accent. Every speaker does, including native English speakers. What matters is whether the listener has to work to understand you. Stress, rhythm, and intonation count just as much as individual sounds. The aviation pronunciations — "tree" for three, "fife" for five, "niner" for nine — exist to remove the hardest sounds. Use them. They are not optional.
Structure
Can you build sentences that hold up under pressure?
You do not need flawless grammar. You need grammar that does not break down when something unexpected happens. Examiners look at how you handle the basic patterns — tenses, word order, agreement — and how those patterns survive when you have to think on your feet about an emergency, a weather change, or a clearance you did not expect.
Vocabulary
Do you have the words for the situation?
Standard phraseology is a fraction of what you need. The rest is plain English for everything outside the script — describing what you see out the window, explaining a problem, asking for help. If you do not know a word, can you work around it? Examiners notice when a pilot pauses for a missing word, and when one finds another way to say the same thing.
Fluency
Can you speak without stalling?
Fluency is not speed. It is the absence of long, distracting pauses. Aviation English has its own rhythm — short, clipped, predictable. Examiners listen for whether you can hold that rhythm when the topic shifts from routine to non-routine. Fillers like "um" are fine in moderation. Five-second silences while you assemble a sentence are not.
Comprehension
Can you understand what is said to you?
This is half of the test. Examiners play you ATC recordings and ask questions about them. Some are clean studio audio. Some have radio static and unfamiliar accents. The criterion is not whether you understood every word — it is whether you understood the meaning well enough to act on it correctly.
Interactions
Can you handle a conversation, not just a transmission?
Aviation English is not a monologue. Things go wrong. A controller says something unexpected. You miss half of a clearance. The situation changes. Interactions tests whether you can ask for a repeat, clarify what you heard, confirm what you mean, and keep the conversation moving when it does not go to script. This is the criterion most pilots underestimate.
The one rule most pilots get wrong
Your final ICAO score is not the average of your six scores. It is the lowest one.
A pilot who is excellent at five things and weak at one fails the test. A pilot who is solid at all six passes. Examiners look for your weakest moment, not your strongest one.
This is why drilling only your strongest skill does not help. The bottleneck is somewhere else. Most pilots who fail Level 4 fail on Interactions or Comprehension — not on Pronunciation or Vocabulary, which are easier to study and easier to feel confident about.
The six levels — what they actually mean
ICAO defines six levels of proficiency. Levels 1 through 3 are below the bar to fly internationally. Levels 4, 5, and 6 are operational.
Level 1 — Pre-Elementary. Below the level required for basic communication. Cannot fly under ICAO rules.
Level 2 — Elementary. Can produce isolated, memorized phrases. Cannot hold a conversation. Cannot fly under ICAO rules.
Level 3 — Pre-Operational. Communicates on familiar topics with hesitation. Errors often interfere with meaning. Not enough to fly internationally.
Level 4 — Operational. Communicates effectively in routine situations. Handles unexpected events with some difficulty. Has a noticeable accent that occasionally requires effort from the listener. This is the legal minimum to fly internationally.
Level 5 — Extended. Communicates effectively in routine and most non-routine situations. Fewer errors, faster recovery, broader vocabulary. Often preferred by major airlines at hiring.
Level 6 — Expert. Near-native ability. Comfortable across nearly all contexts. Valid for life — never retested under ICAO rules.
How Avilingo scores you
Avilingo uses the same six criteria. Every drill you complete gets scored on pronunciation, structure, vocabulary, fluency, comprehension, and interactions — not on a single overall number that hides which one is dragging you down.
You see your weakest criterion every time. That is the one you work on next.
The scoring is automated using speech recognition trained on aviation English. It is not an examiner — no AI is. But it is calibrated to the same Doc 9835 standard examiners use, so the practice translates.
How long your certificate lasts
| Level | ICAO validity | EASA validity |
|---|---|---|
| Level 4 (Operational) | 3 years | 4 years |
| Level 5 (Extended) | 6 years | 6 years |
| Level 6 (Expert) | Lifetime | Lifetime* |
Most pilots aim for Level 4 the first time. After two or three renewal cycles, many move toward Level 5 — partly because the validity period is longer, partly because major airlines often prefer it at hiring. Level 6 is rare and usually awarded only to near-native speakers.
Common questions
- Do I have to be a native speaker to pass?
- No. Most pilots passing at Level 4 or Level 5 are not native speakers. The scale was built specifically with non-native speakers in mind. Your accent will not stop you from passing — what matters is whether you can be understood and whether you can handle a real conversation.
- Can I fail one criterion and still pass overall?
- No. Your overall level equals your lowest score across the six criteria. A single Level 3 anywhere makes the whole result Level 3, even if everything else is Level 5.
- How long does the test take?
- Most test formats run 20 to 30 minutes. The test covers listening and speaking only — no reading, no writing.
- Which test format should I take?
- Any test format approved by your national civil aviation authority. The six criteria and six levels are the same across all approved formats — only the test structure differs. Common formats include TEA, EALTS, ELPAC, sayagain, and ICAO4U.
- How long should I prepare?
- It depends on your starting English level. A pilot with strong general English usually needs 4 to 8 weeks of focused aviation-English practice. A pilot starting at Level 3 might need 3 to 6 months. Consistency matters more than total hours — daily short sessions beat occasional long ones.
- Is the certificate valid worldwide?
- ICAO certificates are recognized by all 193 ICAO member states. Validity periods vary slightly between ICAO standards and EASA standards — see the table above.
You do not have to memorize all of this
You have to practice the six things the test measures. That is what Avilingo is built for.