FREE · 30 CLEARANCES · 3 SPEEDS · AUTO-CHECKED
ATC Readback & Numbers Trainer
Hear an ATC clearance, type your readback, and see every item checked — call sign, flight level, heading, QNH, squawk, frequency, runway and conditions. Three levels, from slow single instructions to fast multi-part clearances.
Type the readback
DEBRIEF
Your readback debrief
ICAO number pronunciation: tree, fife, niner
On the radio, digits are spoken one by one, and three of them change shape so they cannot be confused through noise: three becomes tree, five becomes fife and nine becomes niner.
- 0
- ZE-RO
- 1
- WUN
- 2
- TOO
- 3
- TREE
- 4
- FOW-er
- 5
- FIFE
- 6
- SIX
- 7
- SEV-en
- 8
- AIT
- 9
- NIN-er
- Decimal
- DAY-SEE-MAL
- Hundred · Thousand
- HUN-dred · TOU-SAND
- Flight levelEach digit:
flight level two six zero
(FL260). - HeadingThree digits:
heading zero six zero
— never “sixty”. - AltitudeWhole thousands as a group:
fife thousand feet
(5,000 ft). - QNHEach digit:
QNH one zero one tree
; sayQNH niner niner eight
for 998. - SquawkFour digits, 0 to 7 only:
squawk six fife four six
. - FrequencyDigits with
decimal
:one two seven decimal eight
(127.8). - RunwayTwo digits plus left, right or centre:
runway zero four right
. - Call signAlways end the readback with your call sign.
Why readback accuracy matters in the ICAO test
The ICAO English test is not a phraseology exam: it assesses plain language in an operational context. But numbers sit underneath everything — the listening section plays radiotelephony recordings, and the comprehension score depends on catching flight levels, headings and frequencies first time.
This trainer isolates that skill. Level 1 plays one instruction slowly. Level 2 combines two to four items at normal speed. Level 3 is fast and adds conditional clearances such as behind the landing Airbus, line up and wait
, where the condition must be read back too.
Each session has a code. The same code always plays the same order, so you can replay a session after a few days and measure progress, or share it with a colleague.
More free ICAO English exercises
- Picture descriptionTen scenes with Level 4, 5 and 6 model answers.
- Non-routine situationsTen plain-language speaking prompts with Level 5 model answers.
- Free practice testListening and speaking, with an estimated level.
Readback and numbers: common questions
Why do pilots say “tree”, “fife” and “niner”?
To keep digits distinct on a noisy radio channel. “Three” and “tree”, “five” and “fife”, “nine” and “niner” are the radiotelephony forms, so that a 5 cannot be heard as a 9 through static or a strong accent.
Is readback tested in the ICAO English test?
Not as a phraseology exam. LPR tests assess plain language in an operational context, and a typical test includes listening comprehension of radiotelephony or aviation recordings — where catching numbers accurately is essential to answering correctly.
How does the trainer check my readback?
It reads digits or words (“260” or “two six zero”, “tree”, “fife” and “niner” included), finds each cleared item — call sign, flight level, heading, altitude, QNH, squawk, frequency, runway, route or condition — and marks it correct, wrong (showing what you wrote) or missing.
What level is this trainer for?
Level 1 suits candidates working towards Level 4 (Operational), the minimum for radiotelephony on international operations. Levels 2 and 3 add speed and longer clearances for candidates aiming at Level 5 or 6.
Are these real ATC recordings?
No. They are original clearances with invented call signs and waypoints, voiced with synthetic controller audio through a radio filter.
