To all,

Info, since there seems to be some lack of understanding out there:

The east downwind transition is a a phrase coined by controllers to reduce coordination in house. When PCT and Tower use the phrase "east downwind", there is no doubt what each is talking about.

The use of this airspace for VFR traffic between FDK and BRV evolved after the loss of the VFR flyway at 9/11. It is a way that controllers at IAD (now PCT and IAD tower) could provide a service to VFR flights without sending them around the Class B to the west. It is not a published procedure and there are no guarantees you will get it. I have provided you with the information you can use to maximize the probability of getting it by giving you non-conflicting altitudes with IFR traffic and fixes that tell the controller you can navigate the center of the airspace, clear of IAD and DCA traffic patterns.

IN THE BEGINNING:

IAD controllers were required to vector aircraft in the east downwind, landing 1R/19L. The airspace is very tight, allowing for +/- 1 mile lateral deviation from center before losing lateral separation from either DCA airspace (they owned the VFR Flyway airspace) or traffic departing/arriving rwy 1R/19L. It was very work intensive and involved giving many small vectors to all aircraft, while descending from 10,000 feet to 3,000 feet abeam the airport.

UAL/BLR together with IAD specialists designed a procedure that provided lateral and vertical guidance from the outer fixes (ROBRT,now MULRR, and BARIN). Fixes were defined such that each one included a crossing altitude to keep the aircraft in the narrow corridor and vertically protect from other airspace and traffic flows, while keeping arrivals in the Class B from 20 miles out.

These procedures were called "The ROBRT/BARIN FMS TRANSITIONS". They started at ROBRT, now MULRR in the north for landing 1R, and BARIN in the south for landing 19L and ended 10 miles past the airport in the downwind, from which point the pilot was to expect vectors to final. They were published for use by UAL, and BLR only. They were very successful in reducing pilot-controller communications, controller workload in vectoring, and pilot workload as well, and are in use today. Bureaucracy as always has prevented the publishing of these procedures for use by all air carriers and GA aircraft.

These fixes that were defined for the two TRANSITIONS are published by JEPPESSEN in most databases for GPS navigation, VFR or IFR. Some controllers at PCT will clear non-participating IFR aircraft direct to one of the fixes (usually HUSEL or CARAS from the north, STAYO from the south when the aircraft will not overfly BARIN) to minimize the need for vectoring.

Since these fixes are not in any IFR publication available to the general public, the only way you would know about them is if you know about the TRANSITIONS. That now includes all the pilots reading this message.

You only need to know two or three in order to navigate past IAD in the center of the downwind. I suggest HUSEL, CARAS, and STAYO as the only fixes you need to know, since they are the ones that most controllers will know best, and they form a line bisecting the east downwind.

The fixes are depicted on the controllers radar display for you curious ones out there.

For graphic depiction see www.mcaa-md.org in the RESOURCES section.

ENJOY

Gary Harris
N733BZ based at JYO
CFI-AI, SEL, SES
BGI, IGI, AGI
Controller at IAD Tower
gharris1211@earthlink.net