Definition
Designated points along an arrival route where Air Traffic Control measures and adjusts the flow of aircraft so they arrive at the airport spaced at the required intervals. Controllers assign speeds, altitudes, or holding to ensure each aircraft crosses the metering fix at a specific time calculated to maintain orderly arrival sequencing.
Plain English
A waypoint where controllers time your arrival so aircraft reach the airport in a smooth, evenly spaced stream rather than all at once.
Context Anchor
Seen in instrument procedures, arrival planning, and discussions of floating waypoints or route points used for traffic flow control.
Derivation
‘Metering’ comes from the verb ‘to meter,’ meaning to measure out or release something at a controlled rate — like a parking meter measures time, or a fuel meter measures flow. Applied to aircraft, it means releasing them past a fixed point at a controlled rate so the airport doesn’t get overwhelmed.
Why Pilots Care
Proper crossing of metering fixes ensures smooth sequencing into busy airports, reducing delays and the need for holding patterns.
Analogy
Like a traffic light at a freeway on-ramp that releases one car every few seconds — it keeps the highway flowing instead of letting a clump of cars merge all at once.
Intuition Check
Do not read metering fixes as repair points or maintenance locations. In this context, fixes are position points, and metering means controlling the flow of aircraft through those points.
Example Sentence 1
ATC instructed us to slow to 250 knots and cross the metering fix at 1432 Zulu to fit into the arrival flow.
Example Sentence 2
Floating waypoints often serve as metering fixes during high-traffic periods to maintain efficient flow.