I very carefully said think about how far ahead he is rather than help myself to a slowdown! The TCAS range of 5 miles just happens to be the most convenient on my aircraft as the next range up of 10 miles makes the distances very difficult to estimate.
You guys can be working with a pretty blunt instrument as well. When cleared for the approach our SOP is generally to be flaps five at glide slope intercept and to further configure at 2000' agl, to be stable by 1000'. As our 737 NGs can be considerably slower than the classics (due to crossover speeds), at flaps five there can be up to a third of a mile difference per minute in approach speed if we just fly to SOP. I do not believe you know our landing weight and therefore VREF just on my type alone can differ by 20 knots.
If the guy behind starts catching up we are normally told to maintain 160 to some point which is convenient for you but confusing for my new co-pilots. In the classic it is below flaps 5 speed of 170 so they sometimes ask if they should lower the gear so they can get flaps 15, which is quite the opposite of what you want, which is to maintain separation from the aircraft behind. If the speed reduction point is too close in, (say 4 miles) then we risk not being stable.
I am not having a whinge at ATC, if anything my complaint is about fellow pilots blasting in oblivious to what the guy in front is doing. I do in fact inform ATC if we think a reduction would be helpful. I am not sure ringing up ATC to complain about what other pilots are doing is going to help much. In my opinion the wrong crew gets punished. The purpose of starting a discussion on ATC Issues is to discuss this with ATC professionals. I regularly attend runway safety meetings on behalf of my company and find such exchange of ideas useful.
Last edited by lederhosen; 2nd July 2009 at 10:34.