Initial call structure

Structure of the Initial Call

The initial call on a new frequency or first contact with a station follows a clearly structured format. A correct initial call saves time and gives clear context.

Source: ICAO Doc 9432 Manual of Radiotelephony, ICAO Annex 10 Volume II.

Standard format

[Called station], [own callsign], [type + position + altitude + intentions]

Components in detail

1. Called station (addressee)

• Tower: "Munich Tower" / "Innsbruck Tower"
• Ground: "Munich Ground"
• Departure / Approach: "Munich Departure" / "Munich Approach"
• FIS (Flight Information Service): "Munich Information" / "Vienna Radar"
• Centre (en-route): "Munich Radar" / "Rhein Radar"
• Radar — special callsign for ATC stations with radar service (see below).
• Radio (uncontrolled fields): "[Field name] Radio"
• Information (self-service fields): "[Field name] Information"

"Radar" callsign — what does it mean?

"Radar" as part of an ATC callsign (e.g. "Munich Radar", "Bremen Radar", "Frankfurt Radar") signals that the ground station provides radar identification and service:

• Pilot can query own position (lat/lon, distance from a VOR).
• ATC can issue vectors (heading instructions for navigation).
• Traffic information with radar-based accuracy.

→ When position information is needed: call a Radar station (rather than a pure FIS station, which relies only on pilot position reports).

Example:

• Pilot: "Bremen Radar, DEMRA, request own position."
• ATC: "DEMRA, Bremen Radar, position 5 NM south of Bremen VOR."

2. Own callsign

Full callsign on initial contact (phonetically spelled).

3. Aircraft type (optional but recommended)

• "Cessna 172"
• "Diamond DA-40"
• "PA-28"

4. Position

• Visual Reference Points (VRP): "Over VRP November"
• VOR radial + distance: "TGO 270 radial, 15 NM"
• Distance + direction to field: "5 NM north of Munich"
• Geographic name: "Over Augsburg city"
• Waypoint: "Over BIBOS"

5. Altitude

• AAL / AMSL for VFR: "level 3000 ft QNH 1015"
• FL for IFR / higher: "FL080"

6. Intentions / request

• "Inbound for landing"
• "Request VFR transit through TMA"
• "Request flight information service"
• "Request joining instructions"

Examples

Example 1: VFR approach to controlled field

Pilot: "Munich Tower, Delta Echo Mike Romeo Alpha, Cessna 172, VFR from Augsburg, 5 NM north of field, level 3000 ft QNH 1015, request joining instructions for runway 26."

ATC: "Romeo Alpha, Munich Tower, expect right base for runway 26, descend to 2500 ft QNH 1015."

Pilot read-back: "Right base runway 26, descend 2500 ft QNH 1015, Romeo Alpha."

Example 2: FIS en-route

Pilot: "Munich Information, Delta Echo Mike Romeo Alpha, Cessna 172, VFR from Stuttgart to Ingolstadt, over BIBOS, level 5500 ft QNH 1010, request flight information service."

ATC: "Romeo Alpha, Munich Information, flight information service, QNH Munich 1014, no known traffic, no SIGMETs."

Example 3: Initial call at uncontrolled field

Pilot: "[Field name] Radio, DEMRA, Cessna 172, VFR from Schliedern, 5 NM west, level 2000 ft, request landing information."

Radio station: "DEMRA, runway 08 in use, QNH 1018, wind 100 degrees 8 knots, traffic Piper Mike Romeo Alpha downwind."

Adaptations by station

Ground / Tower (controlled)

• More detail needed in the initial call: parking spot, ATIS letter received, take-off configuration.

FIS / Centre (en-route)

• Shorter: position + altitude + intentions; service requested.

Radio / Information (uncontrolled)

• Position and intentions primary.
• The station gives no clearances, only information.

ATIS letter

At large fields with ATIS: pilot confirms the ATIS letter on the initial call:

"Munich Tower, DEMRA, Cessna 172, with information Charlie, taxi ramp 4, request taxi."

→ Saves ATC repeating weather, runway, QNH.

Listen before speaking

Before the initial call: listen 5-10 seconds on the frequency so that:

• Other ongoing exchanges aren't overridden.
• Traffic situation understood.
• Your call doesn't fall into an ongoing instruction.

Class C Airspace Entry — 5-minute rule

Important: for VFR entry into Class C airspace below FL100 in the vicinity of international airports, the pilot must establish radio contact with the responsible ATC unit at least 5 minutes before the entry.

Reason: ATC needs time for identification, traffic coordination, and clearance issuance. In dense traffic (e.g. Frankfurt, Munich), the pilot may be delayed or refused — with only 1 min lead-time, safe integration would not be possible.

Example call 5 min before entry:

"Frankfurt Approach, DEMRA, Cessna 172, VFR from Heidelberg, 10 NM south of Frankfurt VOR, level 4500 ft QNH 1015, estimating Frankfurt TMA in 5 minutes, request transit eastbound through Class C."

Frequency change — approval required

Important rule (ICAO Doc 9432 §3):

Leaving a controlled frequency (Tower, Approach, Radar, etc.) requires approval from the responsible unit.

The pilot cannot simply switch frequencies without informing ATC — otherwise ATC loses contact and may trigger an emergency alert.

Standard procedure:

1. Pilot requests frequency change: "Munich Tower, DEMRA, request frequency change."
2. ATC approves: "DEMRA, contact Munich Information 124.45, goodbye."
3. Pilot read-back + switches: "Munich Information 124.45, DEMRA, goodbye."

Exceptions:

• FIS / Information: frequency change usually freer, but announce politely ("Switching to next sector, goodbye").
• Emergency: in Mayday/Pan, pilot may switch to 121.500 without explicit approval.
• On leaving controlled airspace (CTR/TMA): after VFR exit call, pilot may switch without approval.

Common errors

• Calling without listening to ATIS: can delay.
• Vague position: "near Munich" — better "5 NM north of Munich".
• Unclear intentions: ATC must ask.
• Too long: initial call as one long sentence → ATC loses detail.
• Frequency change without approval: ATC loses contact → potential emergency alert.
• Class C without 5-min lead-time: entry refusal possible.