Monday, October 11, 2010

How Many Engineers Does it Take?

OAK 09/200 OAK NAV VORTAC OTS TIL 1010312359

The Oakland VORTAC has been out of service for, well ... I think it was NOTAMed back in April or May of 2010. Pretty amazing when you consider this is one of the major navigation aids on the West Coast: It defines six Victor airways, six Jet airways, and numerous airports have instrument approaches, departure procedures, and arrivals that rely on it. So what is the FAA doing to the Oakland VORTAC and why is it taking so long? This isn't the entire story, just some of the pieces.

The Oakland VORTAC was missing in action for an extended period about six years ago when a range of radials had become unusable and an effort was undertaken to figure out why. Around that time the Ron Cowan Parkway had just been completed, named after the developer of the nearby Harbor Bay business and residential developments.

Sometimes called the road to nowhere, the project to build the Cowan Parkway figured in an FBI probe that started after allegations of impropriety between Mr. Cowan and then state senator Don Perata. It seems that some folk thought the road was primarily designed to increase the value of Mr. Cowan's real estate holdings at Harbor Bay at taxpayer expense, but that's a deep topic. So moving on I'll point out that the Cowan Parkway divides the Oakland Airport in half, provides alternate access to the FedEx ramp and the South Field terminal as well as an alternate route for residents of Bay Farm Island. Cyclists also benefit from bike lanes that flank the road.

Building the parkway was a big project, in part because a tunnel had to be constructed under Taxiway Bravo, the only connection for taxiing aircraft between Oakland's South Field and the North Field. In addition, airport perimeter barriers had to be adapted and new chain link fencing and razor wire installed. After investigating, it was determined that the new fences were close enough to the VORTAC that they were distorting the signals. Sections of the fencing were replaced with redwood (which you can see in the photo above), the FAA's flight check aircraft conducted various tests, there were still some radials in the Northwest quadrant deemed unusable, but the VORTAC was returned to service and life got back to normal, mostly.


Recently an initiative was undertaken to dopplerize the Oakland VORTAC to increase its accuracy and eliminate or reduce the number of unusable radials. This is the project that started in earnest last spring and after a month or so, a bunch of little mushroom-shaped antennae were seen ringing the main bowling pin antenna.

In July the flight check aircraft was testing the results. I remember one of the days because the FAA's flight check King Air made quite a stir, flying the OAK VOR RWY 9R approach when all other traffic was landing runways 29, 27 Left and 27 Right. A student I was flying with had to break off a practice approach, but I didn't mind because I assumed this meant progress was being made. Yet as the end of July approached, the NOTAM was changed to show the VORTAC returning to service at the end of September. Then I got wind of some of what was going on.

It seems that the new configuration failed the high-altitude flight check and a new effort was underway to determine why. At one point a theory was that surplus concrete debris that the airport facilities folks use to repair the numerous dikes and levees around the airport was causing the problem. The concrete chunks were piled up near the VORTAC, some of the chunks contained rebar, and the thought was this was distorting the VORTAC's signals. This isn't the first time rebar has affected aviation at Oakland: A few years ago it was discovered that both compass roses had been constructed with concrete that contained rebar, which could explain why so many compasses that were swung at Oakland seemed screwed up. The compass roses remain closed.

USD 05/081 NUQ AIRSPACE SOUTHLAND ONE DEPARTURE... NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS.

USD 05/083 LVK AIRSPACE LIVERMORE ONE DEPARTURE... PROCEDURE NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS.

USD 05/085 SFO AIRSPACE PORTE THREE DEPARTURE TAKE-OFF RUNWAYS 10L/R AND 19L/R: PROCEDURE NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VOR OTS. 

USD 05/097 SFO AIRSPACE SHORELINE ONE DEPARTURE...
PROCEDURE NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS. 

USD 05/082 OAK AIRSPACE SKYLINE THREE DEPARTURE...
RWYS 9L, 9R, 11 NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS.

USD 05/084 OAK AIRSPACE MARINA FOUR DEPARTURE...
NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV
SYSTEM WITH GPS. OAK VORTAC OTS. 

USD 05/149 OAK AIRSPACE SALAD ONE DEPARTURE NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS.

USD 05/087 CCR AIRSPACE BUCHANAN NINE DEPARTURE PITTS TRANSITIONS: NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS.

USD 05/086 APC AIRSPACE LIZRD THREE DEPARTURE OAKLAND TRANSITIONS: NA EXCEPT FOR AIRCRAFT EQUIPPED WITH SUITABLE RNAV SYSTEM WITH GPS. OAK VORTAC OTS.

Another repercussion has been that a local freight carrier cannot use the SALAD ONE departure because many (or all?) of their aircraft are not RNAV equipped. So instead of departing runway 27L or 27R, turning East over the San Leandro Bay, and intercepting the 060˚ radial, they have to fly heading 310 until high enough to be vectored to the East. The 310 heading takes them right over residential areas of Alameda late at night and in the early morning hours.

Pilots who wish to fly the HWD LOC/DME RWY 28L approach are required to be flying aircraft equipped with a suitable RNAV system because the missed approach holding fix is (wait for it) ... the Oakland VORTAC. I got bitten by this one a couple of weeks ago when the weather into Hayward didn't clear as forecast. My student had to fly the ILS into Oakland, then we sat and waited for VFR weather so we could reposition back to nearby Hayward. Live and learn.

VORTAC with new Counterpoise
I don't know if the theory about rebar in scrap concrete interfering with the VORTAC was itself scrapped, but the latest development was an assessment that the counterpoise (the roof of the VORTAC building) was too small. An effort was undertaken to enlarge the roof, increasing its diameter by some 16 feet to a total diameter of 84 feet. It looks like this part of the project is mostly completed and the latest NOTAM claims the OAK VORTAC should be back in service by the end of October, 2010.

In 2002, the man for whom the road was named defaulted on over $43 million in loans from Lehman Brothers and the investment bank and its property management company seized much of what Cowan owned at Harbor Bay Business Park. The road itself is not heavily travelled, though it did end up reportedly costing taxpayers over $100 million. The road appears indirectly responsible for trouble faced by pilots and a noise-sensitive community. The weather is bound to get worse as winter approaches and fixing the Oakland VORTAC could go down to the wire. We'll just have to wait and see if the FAA can pull a rabbit out of their hat or if the Cowan Parkway will continue to be the gift that keeps giving.

1 comment:

Flyerist said...

Great post. I always wondered why the OAK VOR had such problems. I noted in my blog post that the OAK VOR is a primary NAVAID for engine-out procedures at SFO, especially from the 28's. For older non-glass airplanes, it would require a new procedure.