Narrative:

Daily, ZOA traffic management publishes at least 3 rtes from the united states to the far east. These rtes vary by forecast prevailing winds. On nov/xx/94 rtes were published and flts released on mostly 1 route, R463 to axele then diverging north. Being part of the 'composite route system,' R463 uses non-standard altitudes (FL300, 320, 340, 360, etc). Further it is a bi-directional route. This forces traffic into a sector not designed to work the volume and creates sits by transitioning out of composite to standard separation. It caused many difficult, unusual and potentially dangerous sits that were unnecessarily created by this event. In short, the sector ultimately responsible for separating this heavy traffic from several crossing flts did not have control of the aircraft. Further, because on transitioning from composite altitudes and standard altitudes, and because reduced separation via mach assignments is not available at different altitudes (ie, 340 versus 350). The task became extremely complex. Keep in mind, the united states far east flow is released based on being able to utilize mach technique, so the standard 15 min rarely exists. Opposite direction traffic on R463 existed to create further sits. Callback conversation with reporter revealed the following information: reporter indicated that the use of varying oceanic rtes pertaining to the forecast of prevailing winds has been stopped. Reporter believes that the separation standard for these rtes will be changed thereby eliminating any of the problems indicated in the report.

Google
 

Original NASA ASRS Text

Title: OCEANIC RTE ALT ASSIGNMENT FOR FORECAST OF PREVAILING WINDS.

Narrative: DAILY, ZOA TFC MGMNT PUBLISHES AT LEAST 3 RTES FROM THE UNITED STATES TO THE FAR EAST. THESE RTES VARY BY FORECAST PREVAILING WINDS. ON NOV/XX/94 RTES WERE PUBLISHED AND FLTS RELEASED ON MOSTLY 1 RTE, R463 TO AXELE THEN DIVERGING N. BEING PART OF THE 'COMPOSITE RTE SYS,' R463 USES NON-STANDARD ALTS (FL300, 320, 340, 360, ETC). FURTHER IT IS A BI-DIRECTIONAL RTE. THIS FORCES TFC INTO A SECTOR NOT DESIGNED TO WORK THE VOLUME AND CREATES SITS BY TRANSITIONING OUT OF COMPOSITE TO STANDARD SEPARATION. IT CAUSED MANY DIFFICULT, UNUSUAL AND POTENTIALLY DANGEROUS SITS THAT WERE UNNECESSARILY CREATED BY THIS EVENT. IN SHORT, THE SECTOR ULTIMATELY RESPONSIBLE FOR SEPARATING THIS HVY TFC FROM SEVERAL XING FLTS DID NOT HAVE CTL OF THE ACFT. FURTHER, BECAUSE ON TRANSITIONING FROM COMPOSITE ALTS AND STANDARD ALTS, AND BECAUSE REDUCED SEPARATION VIA MACH ASSIGNMENTS IS NOT AVAILABLE AT DIFFERENT ALTS (IE, 340 VERSUS 350). THE TASK BECAME EXTREMELY COMPLEX. KEEP IN MIND, THE UNITED STATES FAR EAST FLOW IS RELEASED BASED ON BEING ABLE TO UTILIZE MACH TECHNIQUE, SO THE STANDARD 15 MIN RARELY EXISTS. OPPOSITE DIRECTION TFC ON R463 EXISTED TO CREATE FURTHER SITS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR INDICATED THAT THE USE OF VARYING OCEANIC RTES PERTAINING TO THE FORECAST OF PREVAILING WINDS HAS BEEN STOPPED. RPTR BELIEVES THAT THE SEPARATION STANDARD FOR THESE RTES WILL BE CHANGED THEREBY ELIMINATING ANY OF THE PROBS INDICATED IN THE RPT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.