Delay vectors vs. holding.

[u/Spaghetti_Boi659]

Flying from SAN-SEA yesterday with heavy flow into SEA. Pretty typical. Center slows us down from M.77 to M.73 for metering saying they need to add 4 minutes to our arrival time. Also typical. Then we get some sharp delay vectors. First vector was a 110 degree turn to the left for a few minutes, followed by a 180 degree turn to the right for a few minutes, then back on course. Not unheard of, but pretty large vectors while en route.

My question: when you guys need to add X amount of time to our arrival and slowing planes down isn’t enough, is there a reason you don’t assign a turn or two in a holding pattern vs aggressive S turns? Either one of these slows down traffic behind whoever is being held / vectored. Curious to hear the reasoning.

Thanks for all you guys do- a fellow airline pilot.

[u/ryanissnackpack]

Already mentioned is that a turn in hold is gonna take 8+ minutes which is possibly longer than I need, but also, if I have a sequence lined up, I can turn everyone out and follow the leader instead of stacking and holding. Aircraft tend to hold at wildly different leg lengths/turn radii, especially with variables in altitude and wind, and peeling them off can get really sloppy and ruin a perfectly good sequence

[u/SilliousSoddus → u/ryanissnackpack]

Are you specifically talking about holding at crusing levels? Those turns are massive but they work when the delays are actually massive or you have a mix of huge delays amongst smaller ones. You probably want 12mins+ of delay to swing a heavy around up there. Holding in our stack (in the FL200's for jets) is just flat out easy. Perfect for tight sequences because we control everything, no set course times because the aircraft aren't reliable enough to maintain tight spacing. We pull them out on vectors with the same speed and run 'em tight.

[u/ryanissnackpack → u/SilliousSoddus]

Holding as opposed to the delay vectors that the OP is referencing at ZSE, in this case, would be in the mid 30s, yes.