you said "Cleared fix..." is radar vector, and if aircraft should go some fix to join airway, What term should controller use?
No, I said that any IFR clearance that sounds like "Cleared to XYZ airport via direct FIX, airway 123, ..."
etc. is a radar vector (present position direct
to FIX) which wouldn't be possible. Instead, assuming they're even going to issue the pop-up IFR clearance at all, I'm guessing they would do one of two things:
1. Issue a VFR climb to the minimum safe altitude before giving the IFR clearance (which still won't be from "present position" - it will have to begin at some fix and utilize airways since radar separation can't be used).
2. Utilize section 4-2-8(d)(1) of the 7110.65:
1. Before issuing a clearance, ask if the pilot is able to maintain terrain and obstruction clearance during a climb to the minimum IFR altitude.
Pilots of pop-up aircraft are responsible for terrain and obstacle clearance until reaching minimum instrument altitude (MIA) or minimum en route altitude (MEA). Pilot compliance with an approved FAA procedure or an ATC instruction transfers that responsibility to the FAA; therefore, do not assign (or imply) specific course guidance that will (or could) be in effect below the MIA or MEA.
“November Eight Seven Six, are you able to provide your own terrain and obstruction clearance between your present altitude and six thousand feet?”
The last part of the NOTE is where I was suggesting that the pilot would not be given any specific guidance on how to reach the first fix where the IFR flight begins; the pilot would need to maintain his own terrain and obstruction clearance while navigating to that fix (which might be direct, might be a curved path around terrain/weather, etc. etc.).