What does the acronym OTPRB or C stand for?


I have been noticing either of those two acronyms (OTPRB or OTPRC) lately on airborne planes and can’t find a reference anywhere. They aren’t equipment codes and don’t seem to be tied to aircraft type. One of them today was a C425/441 favorite of mine that bounced through here but was flight planned from his normal point of departure to OTPRB but after he re-entered the enroute system it showed him from a nav point to his actual destination…


Could it be a similar situation like Fort Myers?

discussions.flightaware.com/view … 3019#43019




I found this one via Google 8)



Ah, missed that bit of one of the better “exchanges” between yourself and “UNoHoo”. Those last few comments make sense because the two OTPRB references today were both out of Oakland, one a C-172 home based in the Reno area and the other was the C-425 based at North Field at KOAK. Others previously would also have had to do with Oakland Center.
Using this line of thought, PRB is Paso Robles VOR/DME but that is 173nm SSE of Oakland. Don’t think either plane was going that way.
Wish I knew someone in Oakland ARTCC or NorCal TRACON.

Thanks, Allen.


Exactly, that was one of the two I noticed. You are just too efficient, must work for the gubmint. :laughing:
Thanks, agin.


It has been suggested by a reputable source that the letters could stand for OutsideThePrimaryRADARBoundary, or, OutsideThePrimaryRADARControl.
Awaiting further information . . .


Probably entered by the clearance delivery controller as an IFR to VFR on top clearance.
Similar to another thread regarding bogus fixes.


That is the correct answer.
I finally got around to calling NorcalTRACON last week and a busy controller said it stands for ‘IFR flight following from departure to VFR OnToP’ and the remaining characters might signify the next fix or the destination.
It makes sense because I always notice it in the SFO Bay Area or along the coast where the marine layer can come in, be up to 3,500’ feet deep, and extend clear into the Central Valley
Apologies for not updating the thread. :blush: