KIAD departures to the south, why the circuitous routing north?

[aa73]

Hi all,

I noticed the other day while commuting IAD-MIA, that every time we take off from one of a southerly runway (19s) or even 30, instead of continuing straight ahead (19s) or a left turn to the south (30) on a southerly route (IAD-MIA), ATC has us turning right all the way around to the north and east, almost over DCA, before heading south. Seems to add a good 10mins and who knows how much extra fuel, to the flight. Is there an airspace restriction that prevents us from taking off to the south and climbing out in that direction?
Thx

 

[Blueridgeflyer]

Potomac and ZDC sequence arrivals into a whole host of airports in the lane you speak of (GVE north towards OTT). When I was based there I was only able to transgress west to east across it at 7000 or below. For DIW, ARs and coastal points to the south Potomac will almost always give you the scenic route to the east of P56 then turn you south towards DAILY. In order to continue a departure path to the south ATC would need to get you south and west to at least FAK before cutting you loose. So the circuitous route is sometimes fastest oddly enough.

 

[aa73]

Thx, that's what I was looking for.

Long Live ACA!!
73, ex Blue Ridge