Position Reports and Air-Reports

When position reports are made

On routes defined by designated significant points, position reports are made when over, or as soon as possible after passing, each designated compulsory reporting point. Compulsory is the operative word: significant points come in compulsory and on-request varieties, and only the first demands a report unasked. The ATS unit may request additional reports over other points. On routes not defined by designated significant points, reports are made as soon as possible after the first half hour of flight and at hourly intervals thereafter. Two refinements complete the rule: flights may be exempted from position reports under conditions specified by the appropriate ATS authority (the case where surveillance already feeds the controller adequate flight progress data) and, when prescribed in the AIP or requested, the last report before crossing into an adjacent FIR or control area is made additionally to the unit about to be entered, so the receiving controller hears the handoff from the aircraft itself as well.

The six items of a voice position report

A full voice position report carries six elements, in a fixed order a crew can rattle off under load:

Aircraft identification — who is reporting.

Position — the significant point just passed.

Time — the time over that point.

Flight level or altitude — including the passing level and the cleared level when the aircraft is not maintaining the cleared level.

Next position and the time over it — the estimate the controller's procedural picture runs on.

Ensuing significant point — the one after that, name only.

The omission rules around this list are where the exam hunts. The last three items (level, next position with time over, and ensuing significant point) may be omitted from voice position reports when so prescribed on the basis of regional air navigation agreements: the simplified position report, cutting the call to identification, position and time where the ground picture makes the rest redundant. One item forces its way back in, and one outside element joins it. The level shall always be included in the initial call after a change of air-ground voice communication channel: a new controller must hear the level from the crew once, whatever the surveillance shows, because that read-across verifies the Mode C data on the label. And when the aircraft has been assigned a speed to maintain, the crew include that speed in their position reports and in the initial call after a channel change: an assigned speed is part of the spacing plan, and each new controller needs to know it is still being flown. The omission the other way: the level element may be dropped from routine reports where pressure-altitude-derived level information from SSR Mode C is continuously available to controllers in the labels on their displays, with procedures in place to use it safely.

One phraseology rule belongs to this learning-objective block: when the level being reported is a flight level (vertical position related to 1,013.2 hPa), the figures are preceded by the words "FLIGHT LEVEL". An altitude on QNH is spoken as the number followed by "feet". The words are the reference: a controller hearing "flight level 80" and "8,000 feet" hears two different datums, and the phrasing carries that difference.

ADS: reports without the voice

The acronym the syllabus asks for: ADS (automatic dependent surveillance). Automatic, because no crew action is needed per report; dependent, because everything comes from the aircraft's own navigation and pressure-altitude sources; surveillance, because the ground uses it to watch the flight. In the ADS-C (ADS contract) version used over oceans and remote areas, position reports are made automatically by data link to the ATS unit serving the airspace, under an ADS-C agreement: the controlling ATC unit establishes what is reported and how often, communicates it to the aircraft, and the contract is acknowledged: the machine version of the compulsory reporting point, negotiated instead of published.

Air-reports and the compulsory special list

When meteorological or operational information rides along with the position information, the whole becomes an air-report. A routine air-report by data link has three sections: position information (the six familiar items, and here the level may never be omitted), operational information (estimated time of arrival and endurance, sent only when the operator asks or the pilot-in-command deems it necessary), and meteorological information (wind, temperature and companions, per Annex 3). All air-reports are made as soon as is practicable. The examinable core, though, is the special air-report: the observations every aircraft shall report whenever encountered or observed:

Moderate or severe turbulence — note the threshold: moderate already obliges the report.
Moderate or severe icing — the same moderate threshold as turbulence.
Severe mountain wave — severe only.
Thunderstorms without hail that are obscured, embedded, widespread or in squall lines — an isolated, visible cell does not qualify; hidden or organised convection does.
Thunderstorms with hail that are obscured, embedded, widespread or in squall lines.
Heavy duststorm or heavy sandstorm.
Volcanic ash cloud.
Pre-eruption volcanic activity or a volcanic eruption — unusual or increasing activity that could presage an eruption counts, not just the eruption itself.
Runway braking action encountered that is not as good as reported — the ground-facing member of the list: the next crew brakes on your report.

For transonic and supersonic flight three additions apply: moderate turbulence, hail, and cumulonimbus clouds, hazards a subsonic crew rides through but a supersonic airframe cannot. The pattern across the whole list rewards attention: turbulence is reportable at moderate, mountain waves only at severe, and icing at moderate; the thresholds differ item by item, and the exam swaps them deliberately.

When position reports are made

The six items of a voice position report

Check you understood

ADS: reports without the voice

Air-reports and the compulsory special list

What the exam asks