"Fly heading 195 out of GILBY..."

[Rocketman99]

OK, many times flying into IAD on the JASEN4 arrival I've been given some clearance like "fly heading 195 out of GILBY" or "after GILBY fly heading 195." GILBY is the last waypoint on the arrival, 6 DME off the AML VOR. My question is, am I expected to lead the turn to 195 and start it around 7.5 DME or so or am I expected to wait until 6 DME, THEN turn to a 195 heading? We are expected to use normal lead points for turns on airways and the like, so is the same thing true here? In case it helps someone answering, it's not a GPS flyover or flyby point. Thanks, this has been an ongoing debate...

[TFaudree_ERAU]

I'd say with the airspace being as tight as it is up there, they want you to wait until passing over GILBY before making the turn. A 4 mile left base leg should be sufficient, right?

And...the clearance is "AFTER" GILBY, fly heading 195.

[casey]

dont lead it.

when you are leading turns enroute you are transitioning from one course to another. there is nothing to lead in this case because you are not intercepting a new course, you are just turning to a heading.

[surreal1221]

Yeah, don't lead it.

[Fox Xray]

Do not lead the turn. Here's why... GILBY (or any fix for that matter) might be on the boundary between the sector issuing the heading and a sector you are leaving. If you lead the the turn you are turning in airspace that you are not cleared to maneuver in... that's a pilot deviation. Happens more then you would believe.

Another reason is when issued depart GILBY on heading 195 turning early will put you in a different spot then the controller expects.

The newer Airbus aircraft always lead turns when joining routes... this has lead to many errors by controllers especially at higher altitudes and speeds. I often see Airbus A/C lead turns by 5-8 miles, this is why myself and many controllers issue headings to Airbus A/C to joins airways if traffic is tight.