Pilawt
Final Approach
- Joined
- Sep 19, 2005
- Messages
- 9,480
- Display Name
Display name:
Pilawt
As a counterpoint to Ron's thread about the tower opening at KFDK, our tower is closing next weekend, and a number of questions are left unanswered.
Historic Pearson Field, one of the oldest operating airfields in the country, sits on the north bank of the Columbia River, only three miles west of Portland (Oregon) International. Heavy jets on the ILS to PDX runway 10L pass directly over Pearson's runway, at just about Pearson's pattern altitude. Pearson lies within a cutout of the surface area of the PDX Class C, allowing access to and from Pearson from the northwest.
In the mid-1990s a Class D area was created for Pearson, requiring traffic inbound and departing to contact Portland Tower, on a discrete frequency for VUO, to receive wake turbulence advisories and, on a workload-permitting basis, callouts of known traffic. After the initial contact on 119.0, VUO traffic would then switch to CTAF on 123.0 to self-announce in the pattern. According to the folks at PDX ATCT, this has been the only Class D area in the country with no operating tower anywhere within it.
Last year a major renovation project closed PDX Rwy 10R/28L for six months, routing more jet traffic over Pearson. FAA therefore commissioned a temporary tower at VUO on 4/1/2011, primarily to assist in avoiding wake turbulence. It was originally planned for the tower to exist only for the duration of the PDX runway construction, ending in October 2011.
But a nagging issue for years has been TCAS conflicts between PDX traffic and VUO traffic. During east traffic flow (more common during winter months), arriving air carrier TCAS can ping VUO traffic and cause resolution advisories, even if the VUO traffic is entirely and legally within VUO airspace. Airline procedures require pilots to execute a missed approach in the event of an RA, even if the "threat" is in visual contact. The problem lies in the TCAS programming and procedures, not in any actual collision threat. We're told that there have not been any actual NMACs between PDX jets and VUO traffic since the Class C was created.
In any event, FAA allowed the temporary tower to remain in operation an extra six months, in order to gather data on traffic flows and RAs. It has been successful. Coordination between VUO and PDX towers reduced the number of RAs by 2/3. VUO pilots liked having the tower, and asked FAA to keep it. No dice; they say our traffic count doesn't warrant it.
So the tower closes next weekend, and we go back to the tower-less Class D. The good news is that PDX ATCT will now have a dedicated "Pearson Advisory" position. It will provide services similar to those of an FSS for a remote airport: latest hourly wind and altimeter (if the pilot does not have the VUO one-minute wx from ASOS), wake turbulence and known traffic advisories; but no runway clearances or sequencing of VFR traffic. After the mandatory initial callup to PDX tower, VUO traffic will continue to self-announce in the pattern -- only now the "Pearson Advisory" frequency and the VUO CTAF will be the same, no switching back and forth. That's good; we've been lobbying for that for years.
What's not so good is that FAA higher-ups are "still working out" how to "manage access to VUO Class D" from PDX to avoid TCAS -- "we are not done with that process."
Among the draconian measures mentioned as possibilities at an FAA Wings seminar last weekend were:
Historic Pearson Field, one of the oldest operating airfields in the country, sits on the north bank of the Columbia River, only three miles west of Portland (Oregon) International. Heavy jets on the ILS to PDX runway 10L pass directly over Pearson's runway, at just about Pearson's pattern altitude. Pearson lies within a cutout of the surface area of the PDX Class C, allowing access to and from Pearson from the northwest.
In the mid-1990s a Class D area was created for Pearson, requiring traffic inbound and departing to contact Portland Tower, on a discrete frequency for VUO, to receive wake turbulence advisories and, on a workload-permitting basis, callouts of known traffic. After the initial contact on 119.0, VUO traffic would then switch to CTAF on 123.0 to self-announce in the pattern. According to the folks at PDX ATCT, this has been the only Class D area in the country with no operating tower anywhere within it.
Last year a major renovation project closed PDX Rwy 10R/28L for six months, routing more jet traffic over Pearson. FAA therefore commissioned a temporary tower at VUO on 4/1/2011, primarily to assist in avoiding wake turbulence. It was originally planned for the tower to exist only for the duration of the PDX runway construction, ending in October 2011.
But a nagging issue for years has been TCAS conflicts between PDX traffic and VUO traffic. During east traffic flow (more common during winter months), arriving air carrier TCAS can ping VUO traffic and cause resolution advisories, even if the VUO traffic is entirely and legally within VUO airspace. Airline procedures require pilots to execute a missed approach in the event of an RA, even if the "threat" is in visual contact. The problem lies in the TCAS programming and procedures, not in any actual collision threat. We're told that there have not been any actual NMACs between PDX jets and VUO traffic since the Class C was created.
In any event, FAA allowed the temporary tower to remain in operation an extra six months, in order to gather data on traffic flows and RAs. It has been successful. Coordination between VUO and PDX towers reduced the number of RAs by 2/3. VUO pilots liked having the tower, and asked FAA to keep it. No dice; they say our traffic count doesn't warrant it.
So the tower closes next weekend, and we go back to the tower-less Class D. The good news is that PDX ATCT will now have a dedicated "Pearson Advisory" position. It will provide services similar to those of an FSS for a remote airport: latest hourly wind and altimeter (if the pilot does not have the VUO one-minute wx from ASOS), wake turbulence and known traffic advisories; but no runway clearances or sequencing of VFR traffic. After the mandatory initial callup to PDX tower, VUO traffic will continue to self-announce in the pattern -- only now the "Pearson Advisory" frequency and the VUO CTAF will be the same, no switching back and forth. That's good; we've been lobbying for that for years.
What's not so good is that FAA higher-ups are "still working out" how to "manage access to VUO Class D" from PDX to avoid TCAS -- "we are not done with that process."
Among the draconian measures mentioned as possibilities at an FAA Wings seminar last weekend were:
-- hold VUO departures on the ground, and require arrivals to hold outside the Class D, while airliners are at TCAS-sensitive areas on their approaches (delays could be up to 15-30 minutes at "push" times);
-- prohibit pattern work at VUO during PDX high-volume periods; and
-- offset the VUO downwind leg (always north of the airport) to parallel the PDX localizer instead of the VUO runway. This so-called "Bravo Pattern" was actually adopted for evaluation by the airport manager and published by FAA, then withdrawn after further discussion at the Wings seminar.
We have excellent dealings and cooperation with the good folks at PDX ATCT, but unfortunately they're not the ones making the decisions. We're hoping wiser heads will prevail to guarantee efficient access to this vital and historic airport.-- prohibit pattern work at VUO during PDX high-volume periods; and
-- offset the VUO downwind leg (always north of the airport) to parallel the PDX localizer instead of the VUO runway. This so-called "Bravo Pattern" was actually adopted for evaluation by the airport manager and published by FAA, then withdrawn after further discussion at the Wings seminar.
Last edited:
.. That is quite a big error to actually make in onto a sectional.
God help the controller in that postion.