What would an ATC command telling a pilot to maintain a certain speed until a certain distance from the destination sound like?

Question

For example, instructing an aircraft to maintain a speed of 200 knots until it is 10 nautical miles from the destination / runway threshold?

Answer 1

Typically, the speed assignment would be to maintain a specific speed until reaching a definable point (dme fix, navaid, RNAV/GPS fix/waypoint, visual reference point, etc.) as opposed to (a pilot estimated) 10 nautical miles (NM) from a destination or runway threshold. Although, if the aircraft is equipped with RNAV/GPS equipment the crew could create a waypoint/fix 10 NM from the airport/runway threshold.

The Phraseology would be something like: (could be some variation depending on the type of fix/point involved)

"N12345, maintain two zero zero knots until one zero miles from XYZ (fix/navaid/waypoint, etc.)"

Answer 2

In the united-states it would sound something like this, in the absence of an otherwise-useful named fix/waypoint/NAVAID:

Citation 3AB maintain two zero zero knots until ten-mile final.

You are more likely to hear "five-mile final" as that is the latest point ATC is allowed to require the pilot to fly a specific speed, as spelled out in FAA JO 7110.65 5–7–1:

b. Do not assign speed adjustment to aircraft: 4. Inside the final approach fix on final or a point 5 miles from the runway, whichever is closer to the runway.