Sorry, more thread drift.
"Max1
Brisbane Center controllers seem to have plenty of time to query enroute estimates - I have been "pulled up" twice in the last 2 weeks and heard a number of others getting the same treatment.
Had to explain (on the very, very busy CEN freq) our GS and the leg distance to the dude on the panel who insisted that the computer was telling him something different.
On each occasion we have been spot on with our estimates
Horatio,"
Horatio
This person was doing their job. You are not 'getting the treatment'. The controller would have been using the Bearing and Range Line (BRL) function to check the System (computer) estimate for your next position.
The computer uses your Flightplanned TAS and the FORECAST winds (note the Forecast winds are updated every 12 hours) to compute an estimate for your enroute waypoints. The BRL uses your current groundspeed over the distance to fly. The controllers BRL would have come up with the same answer as you, and this would also then not have agreed with the System.
If the System Estimate Time Over (SETO) and BRL are out by more than 2 minutes, or considered unreasonable, the controller is REQUIRED to check and confirm with the pilot as to the Pilot Estimate Time Over (PETO) .
As you would appreciate your G/S may not be constant over the entire leg and would change depending on the ACTUAL wind. I have had discrepancies of up to 10+ minutes when measuring with the BRL over long distances and usually find that the pilot estimate will be close to the system estimate , as the nav gear will usually build the forecast winds in to the estimate.
If there is still a discrepancy, the Pilot estimate will be considered sacrosanct. Its your backside on the line. On the rare occasions we have a PETO we still think may be iffy we will usually build a fair bit of fat into the separation standard, just in case. Were you going to go off radar?
I have lost count the number of times I have queried a pilot after they have given me an unrealistic time, which I have again queried, only to get the same answer , only to get a sheepish voice some minutes later saying that they have had another look ( thank you CRM courses) and the time is close to what I thought it would be. That's okay, that's my job. It is also funny that they usually won't agree with my estimate exactly, but move it a minute either side to let me know I wasn't completely right either.
Also, sometimes when it is queried and doesn't agree and I ask their Mach Number I get e.g."M.81"
" What did you plan?"
" M.78, but we're running behind schedule"
This is not a problem (yet), just let us know. If you are going off radar, or are off radar, this can have big implications e.g. Oceanic airspace.
I had an aircraft some years ago ( no names), going NZ-ML on Melbourne Cup Day and we were quite busy and running them tight in the morning, who got a report from Company that ML was fogged in, and pulled it back to min speed halfway across the Tasman without telling us. Turned up six minutes late at waypoint and caused all kinds of drama. Thats why we have big longitudinal separation standards off radar.
Horatio you weren't getting the treatment, the person was just doing their job. One day it may save someone whose estimate aren't spot on.
Come and have a visit someday. Happy to arrange it in Brisvegas.