Exercise L · for US student pilots
Numbers, altimeter and time
How the FAA says numbers: altitudes, frequencies, headings, the altimeter and the clock.
Worked here at Palo Alto (KPAO). In the app the same prompts use your own home airport and call sign.
Prompt 1 of 5
NorCal Approach says: "N172SP, Palo Alto altimeter 29.91." Read it back.
What the AIM says: Digit by digit after the word 'altimeter' (AIM 4-2-8 d), with your call sign — e.g. 'altimeter three zero zero one'. Never 'QNH', never hectopascals.Prompt 2 of 5
You are level at 12,500 feet with NorCal Approach. Report your altitude.
What the AIM says: AIM 4-2-9 a: separate digits of the thousands plus the hundreds — 'one two thousand five hundred'. Not 'twelve thousand five hundred'.Prompt 3 of 5
Palo Alto Tower says: "N172SP, contact NorCal Approach on one two zero point four five." Read it back.
What the AIM says: 'One two zero point four five' — each digit, and 'point' for the decimal (AIM 4-2-8 e) — with your call sign.Prompt 4 of 5
NorCal Approach says: "N172SP, fly heading zero niner zero, reduce speed to one two zero knots." Read it back.
What the AIM says: Heading as three digits, speed as digits plus 'knots' (AIM 4-2-10, 4-2-11), in the order given, with your call sign.Prompt 5 of 5
NorCal Approach asks: "N172SP, say your estimated time of arrival at Hayward Executive." It is 1420 UTC and you expect to arrive at 1455 UTC. Reply.
What the AIM says: AIM 4-2-12: UTC in four separate digits — 'one four five five Zulu' ('Zulu' may denote UTC). Minutes only ('five five') where no misunderstanding is likely.
What this exercise is graded against
| Call or readback | Graded against |
|---|---|
| Altimeter setting: the word then four digits | AIM 4-2-8 d |
| Altitudes below 18,000 feet: thousands digit by digit plus hundreds | AIM 4-2-9 a |
| Frequencies: digits with 'point' | AIM 4-2-8 e |
| Headings as three digits; speed as digits plus 'knots' | AIM 4-2-10; 4-2-11 |
| Time: four digits UTC, 'Zulu' | AIM 4-2-12 |
Now say them to a controller
Push-to-talk, at your airport, with today’s altimeter. The AI controller answers and the grader tells you what the AIM says about each call.
Prompts and notes are written in our own words from the FAA Aeronautical Information Manual (Change 3, 7/9/26) and the Pilot/Controller Glossary, with paragraph references. Frequencies are from the FAA NASR data and are for training only. Study aid; not approved or endorsed by the FAA. Always defer to the AIM, current FAA publications, your instructor and your examiner.