December 29, 2010

Differently Similar

I was sitting at Sector 22 (Albany - ALB) all day it seemed. If I wasn't on break, I was at Albany. And when I was at Albany, the same five planes seemed to fly through at the exact same time. Sure, there were a few other planes here and there, but they weren't in the way like these same five over and over.

I've talked about Albany before, but lets go over some basics first.

This is a simplified map of ALB sector. Lets go over some locations.
Each little circle is a VOR:
ALB - Albany, NY
CAM - Cambridge, NY
CTR - Chester, MA
BDL - Bradley (Hartford), CT
PWL - Pawling, NY
EEN - Keene, NH
DNY - Delancey, NY

The ALB sector is surround by 12 other Boston Center sectors, and completely overlays the Albany Approach Control, who owns 10000 feet and below. The northern half of the sector owns 11000 feet up to FL230 (23000 feet), and the southern half owns FL180 up to Fl230.

MPV - Montpelier Sector 52 owns from the ground to FL230.
CON - Concord Sector 37 owns from the ground to FL230.
GDM - Gardner Sector 36 owns from the ground to FL230.
BOSOX - BOSOX sector (named for an intersection used by Boston departures) owns 11000 up to FL230 (mostly).
Sector 20 is the IGN - Kingston Sector which owns FL200 and above (mostly).
Sector 05 (Stewart) and Sector 06 (Pawling) own 7000 up to FL190.
Sectors 23/24 (Hancock and Delancy, in my area discussed previously) owns mostly from the ground to FL270.
Sector 08/09 (Watertown and Utica, also in my area) owns from the ground to FL600.
Sectors 07 (Chester) and 21 (CANAN) are usually combined since they are so small, and they own 11000 to 17000 underneath ALB and parts of BOSOX.
Two Sectors not shown are CAM - Cambridge Sector 39 which owns above the northern half of the ALB sector FL240 and above. ATHENS Sector 38 owns above the southern half of the sector also FL240 and above.

Now that we have our bearings (I hope), lets talk about the airplanes.

Albany works primary flows of traffic that are pretty constant, but also many planes that are simply flying through randomly. The primary flows are EWR (Newark) area arrivals southbound over ALB, LGA (LaGuardia) area arrivals southbound to PWL, pretty much any other airport near New York City descending southbound, MHT (Manchester) arrivals eastbound to EEN, PVD (Providence) and ISP (Islip/Long Island) arrivals eastbound to a point just west of CTR called PONEE and then to BDL, BDL (Hartford) arrivals eastbound from Sector 24 descending into Sector 21, BDL departures over CTR to CAM, and ALB departures going northwest, west and south. The random traffic includes aircraft transitioning to and from the Mid Atlantic states going to northern New England, Montreal traffic, props going to and from the Boston area, Philly traffic going over DNY, and occasional military refueling missions. There is lots of variety. I love the ALB sector!

But out of all of these, there are really only five instances of total conflict, guaranteed. Figure One. Green lines are climbing, Red lines are descending.

ATHENS gives us MHT arrivals descending to FL240. Our job is to descend them to either FL190 or FL210, and hand them off to GDM-Sector 36. The main determining factor in which altitude we assign depends on BDL departures. Most of them fly over CTR and then go to CAM and then westbound to SYR (Syracuse, NY). A few go west over HNK, but the majority fly to CAM, and are almost always in the way of the MHT arrivals. As the BDL departures cross the MHT flow between CTR and CAM, they are usually climbing out of FL190 for FL230. So a decision must be made. Can I outclimb the MHT with the BDL? Or should I stop the BDL at FL200 and stop the MHT at FL210 and wait for them to pass before climbing the departure?

If I stop the BDL departure, I am increasing the chances that that aircraft will be low enough to later conflict with the other major flow in the sector: EWR arrivals.

If I can't climb the BDL departure right away, or they just climb slow anyways, they are usually in the way of the EWR arrivals just west of CAM as they turn towards SYR. The CAM sector will usually tell us to keep them on a northbound heading to go around the back of the EWR traffic, but sometimes they just get stuck underneath. This is bad. EWR traffic is usually cleared to cross ALB at 16000. As strange as it seems, EWR Traffic goes below the BDL arrivals which cross 15 miles south of ALB descending to FL180. Both EWR and BDL traffic are handed off to Sector 21 who then further descends them once they cross.

The BDL traffic is only one reason we are always pushing to EWR jets lower. Another reason are the southbound ALB departures. They come climbing off the airport on a northwest heading. They don't get to turn south until they outclimb the EWR and BDL arrivals, or we can squeeze them into gaps between. This is the best part of the ALB sector, in my opinion. Whether or not you have a three way scare just south of ALB is up to you. We can leave the departure on the northwest heading until they're out of FL190 and then turn them back south, or we can send them west and then circle them around a BDL, or we can crank them south to PWL right away and tell them to climb like they're life depends on it, narrowly cutting in front of a EWR jet. Sometimes we can push the BDL arrival below the EWR, and then we have a few thousand feet less to get clear. Each scenario is different.

And yet, as I spend my whole day at Albany, the fact that I keep getting five planes at the same time is getting really old, really fast. The BDL departure departs, the EWR arrival is handed off to me descending quickly to meet the restriction from CAM sector, I get a departure message for a southbound ALB departure, here comes the MHT arrival turning direct EEN, and lo and behold, a BDL arrival screaming in from the west. It takes me 6 minutes to work it all out, 11 transmissions in total, and I am left with no airplanes for a few minutes. I may work a few stragglers here and there. The JFK-Burlington Jetblue, an Air Canada south to LGA, and/or a northwest ALB departure, but all of them are route separated. But once those are through, I take my five handoffs again and 6 minutes later 500 people are safely on their way.

After three or four instances of this, I start noticing a pattern. And so after my next break, the pattern continues. Five planes, three conflicts, six minutes, eleven transmissions, moving on with my life. The monotony is broken when one of the BDL departures turns left at CTR and heads to Pittsburgh via HNK. He's not in conflict with the MHT (yay!), but now he and the ALB departure are climbing up to Fl230 converging just north of PWL. Sigh. Who's climbing faster? Both are climbing about the same. I analyze it a few seconds more. I turn the ALB departure a little left to go behind the BDL departure and coordinate the change with ATHENS, giving them control to turn him back to PWL when they pass. And then I'm left with nothing. Waiting for my next break, or five airplanes, whichever comes first.

Till next time...


PS. The moral of the story: Manchester arrivals need to land, but it isn't that urgent. So we try to get our Bradley departures as high as we can so we can get our Newarks down quick so we have a chance to get our Bradley arrivals down and our Albany departures up and on course.

PPS. We also have a pretty nasty conflict at FL210 just west of CTR. It usually involves New York Metro departures at FL210 going to Burlington or Montreal and the PVD/ISP flow descending to FL190 to BDL. If the BDL departure is going over CTR to HNK, plus throw in a LGA arrival southbound to make you reconsider vectoring someone to the west, and BOSOX has a plane climbing a little higher that departed PVD westbound to HNK, it can get ugly, in a multidimensional way. But this happens maybe once or twice a day at the most, not four or five times an hour. So I didn't include this :) Oh wait, I just did!


Dave Starr said...

Glad to see you "on the scope" again. Hope 2011 brings you zero 'deals" and some time to blog. I really enjoy the techy sort of posts like this .. makes me glad I never opted to try for a controller's job, and a marked appreciation for all that you and your brethern do for us all. Thanks.

Frank Van Haste said...


Neat stuff! Ain't it fascinating how our minds will create patterns out of apparently random inputs. And now it's all organized!

I fly the same route, BDR to VKX (near DCA) a lot and I know the pattern of what each control sector is nearly always going to issue to me. So the same thing happens on the other side of the mike.

I don't have to tell you, tho', that familiarity leads to complacency which leads to error. Some damned pilot out there is just waiting to screw you up by not going along with The Pattern. We all have to be sure to respond to what is happening and not to what we expect to be happening.

Thanks for keeping us safe.


Rich said...

Busy, busy. Say, is there an app for that? Welcome back, btw. I enjoy the blog (used to work at RME).

Alex said...

Hi, I love reading your blog. Just wanted to point out that the Chester VOR (CTR) you mention is actually near Chester, MA. The Chester, CT airport (SNC) is southeast of BDL.

deltamike172 said...

Alex, Good catch! Fixed.

Anonymous said...


What would happen if the VOR at BDL was turned off? The Windsor Locks airport wants to build on the airport and would like the VOR out of the way. Would putting in a RNAV waypoint somewhere else and redesigning the airspace help in this aerial ballet you are describing?

deltamike172 said...

In theory, they could just keep a fix called "BDL" and the GPSs would just fly over it. Anyone without a GPS or RNAV would either not be able to fly the airways, or would have to keep recieving the other VOR at the other end of the airway and then transition over BDL to the next radial off the next airway. Some airways would still be in use, others not.

There are big plans for airspace redesign in the works over the next 5-10 years supposedely.....who knows what will happen.