Sunday, July 1, 2007

New Approach(es)

I was introduced to a bunch of new things this week. I got to handle an iPhone and no, I'm not the proud owner. Fancy, flashy devices like this don't fit well with the Flight Instructor Vow of Poverty, but the physical design and user interface are both very slick. If only the designers of the iPhone could redesign aviation GPS user interfaces, that would rock my world.

While having lunch at a local, non-towered airport, I had the chance to ride a Segway. I know the Segway is not new, but I'd never had the opportunity to try one. With a little instruction from the owner, I was easily able to scoot around, accelerate, stop, and make very short radius turns. The stabilization technology in this thing is waaay cool and you move forward or backward by simply redistributing your weight on your feet. Again, the cost of ownership is beyond my modest means, but I admire the design and construction of the Segway.

Cirrus revealed a mock-up of the single-engine jet they are developing, which is an intriguing design. While I realize that the shape of the tail was driven by the positioning of the jet engine, I have to admit that the first thought that went through my mind was "The prophecies have come true! It has a fork-ed tail!" The second thought that went through my mind was "Given the pressurized hull, I sure hope the doors stay shut on this puppy."

A few pilots I regularly fly with pointed out to me that the July 5, 2007 revision of instrument approach procedures for California contain two new approaches for the Hayward airport. I wasn't yet aware of these new approaches because, for whatever reason, my Jeppesen revisions had not yet arrived. At least three pilots I fly with had received their updates last week, but I just received mine yesterday. The two new approaches are the HWD RNAV (GPS) Y 28L and the HWD RNAV (GPS) Z 28L. The HWD GPS 28L approach will be deleted as of July 5, 2007. If you're wondering why two new approaches and what's up with the Y and the Z included in the name of the approaches, here's the deal.

It used to be that the inclusion of a letter was just for approaches that had no straight-in minima due to the approach course being more than 30˚ out of alignment with any runway or because the descent gradient from the final approach fix to the threshold crossing height exceeded 400 feet per nautical mile (this is usually due to terrain or obstacles close to the airport). In these cases the letter A, B, C, or D was included in the name of an approach and there was no mention of a specific runway in the title, such as the HWD VOR or GPS A approach.

As always, do not use any of these approach representations for actual navigation.


With the advent of RNAV (area navigation), the need arose to create different approaches to the same runway that used the same type of approach guidance. Existing FMS and GPS hardware and their databases needed to be able to distinguish between these different approaches, so the design decision (or was it a kludge?) was made to add a single letter to the approach name, but to start at the end of the alphabet and work backwards. Approach names that include the letter Z generally have the lowest minima (though there are supposedly some old approaches out there that violate this convention).

Before getting into the details, I'll point out that instrument approach procedures into Hayward are problematic from the approach controller's perspective. Hayward arrivals conflict with arrivals into Oakland's runway 29 and controllers have to find creative ways to maintain the required separation. Depending on the time of day, there may be a constant stream of arrivals into Oakland and if you're flying a slower aircraft, you can expect significant delays while Norcal tries to make a slot big enough to fit you in. The same is true for instrument departures - more than once I've sat on the ground at Hayward for 20 minutes or more waiting for my IFR release.

Against that backdrop, consider the soon to be defunct HWD GPS RWY 28L which has a convenient initial approach fix at SUNOL at 3900 feet. If an approach controller has to delay your approach clearance due to traffic into Oakland, there's no defined holding pattern and they'll usually put you in a box pattern over the Livermore Valley, north and west of SUNOL. Note that the distance from JOCPI to SUDGE (the final approach fix) is a modest 5 nautical miles and the minimum descent altitude is a respectable 400 feet AGL. That short distance means that once you are cleared for the approach, you should be out of the way of larger aircraft inbound to Oakland fairly quickly.

The new HWD RNAV (GPS) Y 28L has an initial approach fix at ALEYA, which is a whopping 10 nautical miles from the final approach fix at CASGO. My reading of Order 7110.65R and the Instrument Procedures Handbook both say that any vectors issued for an RNAV approach must be to either an Initial Approach Fix or an Intermediate Fix. There even was an accident a few years back that resulted, in part, from a controller vectoring an aircraft to a fix other than an intermediate approach fix.
If you're flying a slower aircraft, this means you'll either proceed direct to ALEYA on your own navigation or the controller will vector you there. And once you're cleared for the approach, this means you'll spend significantly more time in the way of faster aircraft wanting to get into Oakland. If you're told to hold at ALEYA in bad weather, you're at an altitude and in an area that can be conductive to airframe icing. Oh, and the minimum descent altitude for this approach is actually higher than the old GPS approach.

The RNAV (GPS) Z 28L has most of the same disadvantages, but it offers a 300' AGL minimum descent altitude and only 8.8 miles from the IAF to the final approach fix at SUDGE. In short, while I like RNAV approaches and have observed that LPV approaches are easier for pilots to fly accurately, I'm not sure there's any reason to specifically request either approach. The HWD LOC/DME 28L might be a better choice since gets you down almost as low with less time spent in the cross hairs.


If you decide to request one of these approaches and you find the controllers aren't quite up to speed, be patient and remember that they have to learn these new approaches, too. And if the approach controller mistakenly refers to either of these approaches as a GPS approach, remember that approach name items within parentheses are not to be included in either the request for the approach or in the approach clearance phraseology.

Now I'm off to buy a lottery ticket. Who knows, in the near future I just may be able to afford an iPhone, a Segway, and a Cirrus Jet!
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