B737-800
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 153
Situational Awareness; Confusion
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Chart Or Publication; Procedure; Airspace Structure
On the OAKES 2 Arrival to OAK; following the 28L transition; the final fix is BBUBB at 5000 ft. This waypoint at this altitude is well below the floor of the SFO Class B airspace; and as such turbojet aircraft are required by regulation to be at 200 KIAS or minimum clean maneuvering speed at (actually; slightly before) this point. As loaded in the FMC and as published; there is no airspeed associated with the BBUBB waypoint; nor any speed restriction at any prior waypoint that would have the aircraft slowed to the required 200 KIAS. This omission creates several unnecessary threats. First; a Crew that doesn't pull up the SFO range rings may fail to notice that BBUBB is in fact below the SFO Class B airspace and fail to slow. Second; a crew that DOES note the relationship between BBUBB and the Class B airspace will have to override the plan in VNAV in order to be in compliance with the speed requirement. This might involve manually entering a speed restriction of 200 KIAS at BBUBB; or using Speed Intervention and additional drag. Third; when a leading aircraft is aware of the need to be slowed by BBUBB but a following aircraft is not; this sets up a scenario for compression. This happened to us. I noted the relationship to the Class B airspace fairly close to BBUBB and slowed abruptly to 200 KIAS using speedbrakes. The aircraft following behind us was told by ATC to slow to 200 knots; and may have been given vectors for spacing subsequently. There is absolutely no excuse for an arrival designed such that flying it as charted will lead to a Crew violating the below-Class-B speed restrictions. The automation and procedures; in this case VNAV and the charted arrivals; should support the Crews; rather than setting them up for a violation. Some fraction of Crews will miss the not-published-on-the-chart requirement for 200 knots at BBUBB; some fraction will add the speed into the LEGS page and descend accordingly; and some fraction will note the requirement late and slow close-in and aggressively using drag. These differing actions are not predictable by ATC; and set up potentially hazardous situations.The OAKES 2 Arrival specifically; and all arrivals and departures generally; should be scrutinized for places where compliance with the charted speeds and altitudes will place a Crew out of compliance with the below-Class-B speeds; and the procedures should be revised so that the appropriate speeds are coded for the necessary waypoints. For the OAKES 2 Arrival; a NOTAM should be published stating the 200-knot requirement at BBUBB; and the Company weather packet cover page for OAK should state this requirement as well. Don't leave our Crews out there having to guess what restrictions LNAV/VNAV isn't going to meet; with each Crew on their own to (hopefully) adjust their profile to meet the 200-knot requirement. This should be done once and done right at the level of airspace design; rather than leaving it to dozens of Crews each day to 'catch' or not.
A Pilot expressed concern about an RNAV Arrival which requires the aircraft to descend below Class B airspace and reduce speed to 200 knots unexpectedly.