PDX Traffic Management Tips

Portland is located at the end of the Columbia River Gorge.  The gorge produces strong winds from the east.  These winds exit the gorge about 11 miles east of the airport and spread out across the Willamette Valley.  The standard result for PDX Traffic is winds near the surface from the east, above 1500' from the south to west.  Turbulence is a byproduct of these winds.  During the fall and winter, strong south winds above 1500' with strong east surface winds are common, resulting in sequencing problems on final as the aircraft on different base legs can have a speed difference of up to 200 knots.  Once these aircraft are established on final there is a compression of up to 3 miles depending upon the strength of the east wind.

On three to five days a year, PDX will experience a south wind event.  These events produce south winds as high as 50 to 60 knots at the surface and 100 knots at 6000'.  During these events, the runway configuration is a single runway 21 operation.  Many air carriers will not land or depart.

PDX has a Military Guard unit and alert aircraft for coastal defense located on the south side of the field.  The south runway is equipped with arresting cables for those aircraft.  If the cable is used, the resulting delay for the runway is usually about 30 minutes.  When alert aircraft are called out, they can depart opposite direction to the flow and cause delays for the aircraft on final.

Arrivals:

• 3100 feet separate the parallel runways.  2.5 mile final spacing is approved for runways 10L/R and 28L/R.  Charted visual approaches are published for both 10L/10R and 28L/28R for jets and turboprops.  When runway 3/21 is in use with 10R/28L, arrivals must be sequenced for the crossing intersection.
• Rates for the parallel runway configurations are based on staggered approach separation.
• Exclusions to the rate, or plus rates, are used for small "box hauler" aircraft that descend below the bases to cancel IFR and proceed to the airport VFR.  These aircraft are sequenced by the Local controller for landing.  P80 TMC will insure that an arrival hole is developed to accommodate the VFR aircraft.  Plus rates range from 4 aircraft an hour to an exclusion of all the box hauler aircraft during an hour.  These exclusions can also be specific to an arrival route or direction from the airport.
• The majority of PDX arrival and departure traffic comes and goes to the east and south.  There is a lesser amount that travels to and from the north.  Because of this geographic location, we tend to receive volumes of traffic to one side of the airspace or the other.  During these times, off loading traffic to balance the down winds is needed.
• Fog is common between October and May.  There is a Fog plan developed between P80 and ZSE and is implemented when needed.  SMGCS equipment has just been installed and the opportunity to use it has not yet presented itself.

Departures:

• Gate Hold is used when deicing is required.

Other:

• Troutdale (TTD) is located 11 miles east of PDX, underneath the localizers for runways 28.  TTD has one published approach which is opposite direction to the final flow of RWY28 at PDX.  This approach takes 2 to 4 PDX arrival slots to accommodate the entire procedure.
• Pearson Airfield (VUO) is located 3 miles west of PDX and it shares the localizer for runway 10L.  The approach is a LDA and requires 2 PDX arrival slots to accommodate the approach.  The closeness of PDX also causes TCAS events between aircraft.