Reduce to minimum speed

[octavian]

Although, in his original post, Pace didn't given us the context in which the request was made, a later post showed that it related to an aircraft on final approach.

Given that the instruction was given to a biz jet there is a reasonable expectation from controllers that pretty well all turbo prop and jet aircraft will be capable of flying at the generally accepted approach speeds of 240kts below FL100, reducing to 210, then 180 and be expected to maintain 160kts to 4nm final once established and within about 10-12nm. Inside 4nm no speed control can be issued by ATC. Some of the new "mini biz-jets" do have significantly slower approach speeds inside 4nm than other jets including such types as the broad Citation series.

Elsewhere there is a thread running about maintaining separation, and it is the use of speed control during the approach phase which establishes and then maintains the spacing on final approach, whether a distance specified by the tower controller to get best runway utilisation for arriving and departing aircraft or the application of a wake turbulence spacing should this be greater.

Should the spacing be reducing below that which the tower, or indeed radar, controller requires then the phrase identified by Heathrow Director "Reduce to minimum safe approach speed" is a very safe option and in my experience is never queried. Given that a light 757 might have a final approach speed inside 4nm of 125kts (let us know if it is please) perhaps even less and a heavy MD11 could be batting along at 155kts I might ask what the speed might be just to help me decide what happens to the following aircraft, but it is the pilot's call as to the speed flown.

Although Pace did not specifically refer to Cherokees, Chipmunks, Comanches, Cubs and the like, if they are mixing it with pretty much any turbo-prop or jet types the phrase you are most likely to hear is along the lines of "give me your best (fastest safe) speed to short final, what will that be?"

I've just noticed Pace's comment in a later post about a runway obstruction relating to his situation. Perfect example of why "reduce to minimum safe approach speed" might be used. Drag it in fella, we're expecting the obstruction to be cleared it might save a go-around and another 15 minutes in the pattern.

Hope this helps.