Narrative:

I had reported osh en route to ptk. My original intention was to proceed VFR to ptk. WX east of osh was low VFR to IFR, however departing osh in VFR conditions, I was able to climb on top of the WX, through broken then overcast WX at 17500' eastbound. 30-40 mi northeast of the mkg VOR I realized that I could not continue VFR to ptk due to higher cloud ahead. In order to proceed I would have to enter the position control airspace above 18000'. I had difficulty contacting a FSS on 122.2 or 122.5. Finally I was able to raise chicago center. This delay could have been critical had fuel been a factor. I requested RNAV direct ptk from the controller since my aircraft has RNAV unit, approved for IFR flight. I was given direct cratr intersection, direct pontiac. Cratr was described as west of lan on V103. To appropriately identify cratr for an RNAV coordinate, it is 60 DME from yqg. I was 95 mi from this intersection and at altitude FL210, I was not able to receive yqg suitably to navigate to cratr. While trying to fly IFR, and measure 'with a ruler a right and distance from lan, I overshot my altitude by 200'. It would be better if ATC had either assigned a VOR as an intermediate fix, or an intersection that can be defined by radials and distances from 2 sep and different vors, so that if one is not suitable for navigation, the other one will be. I suspect many pilots are given RNAV direct to intxns not easily identifiable, diverting their attention from instruments, while they try to guess the coords.

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Original NASA ASRS Text

Title: SMA PLT VFR IN IMC WITH CLIMB THROUGH BROKEN TO OVERCAST CLOUD LAYER, THEN OVERSHOOTS ASSIGNED ALT AFTER RECEPTION OF IFR CLRNC.

Narrative: I HAD RPTED OSH ENRTE TO PTK. MY ORIGINAL INTENTION WAS TO PROCEED VFR TO PTK. WX E OF OSH WAS LOW VFR TO IFR, HOWEVER DEPARTING OSH IN VFR CONDITIONS, I WAS ABLE TO CLB ON TOP OF THE WX, THROUGH BROKEN THEN OVCST WX AT 17500' EBND. 30-40 MI NE OF THE MKG VOR I REALIZED THAT I COULD NOT CONTINUE VFR TO PTK DUE TO HIGHER CLOUD AHEAD. IN ORDER TO PROCEED I WOULD HAVE TO ENTER THE POS CTL AIRSPACE ABOVE 18000'. I HAD DIFFICULTY CONTACTING A FSS ON 122.2 OR 122.5. FINALLY I WAS ABLE TO RAISE CHICAGO CTR. THIS DELAY COULD HAVE BEEN CRITICAL HAD FUEL BEEN A FACTOR. I REQUESTED RNAV DIRECT PTK FROM THE CTLR SINCE MY ACFT HAS RNAV UNIT, APPROVED FOR IFR FLT. I WAS GIVEN DIRECT CRATR INTXN, DIRECT PONTIAC. CRATR WAS DESCRIBED AS W OF LAN ON V103. TO APPROPRIATELY IDENT CRATR FOR AN RNAV COORDINATE, IT IS 60 DME FROM YQG. I WAS 95 MI FROM THIS INTXN AND AT ALT FL210, I WAS NOT ABLE TO RECEIVE YQG SUITABLY TO NAVIGATE TO CRATR. WHILE TRYING TO FLY IFR, AND MEASURE 'WITH A RULER A R AND DISTANCE FROM LAN, I OVERSHOT MY ALT BY 200'. IT WOULD BE BETTER IF ATC HAD EITHER ASSIGNED A VOR AS AN INTERMEDIATE FIX, OR AN INTXN THAT CAN BE DEFINED BY RADIALS AND DISTANCES FROM 2 SEP AND DIFFERENT VORS, SO THAT IF ONE IS NOT SUITABLE FOR NAV, THE OTHER ONE WILL BE. I SUSPECT MANY PLTS ARE GIVEN RNAV DIRECT TO INTXNS NOT EASILY IDENTIFIABLE, DIVERTING THEIR ATTN FROM INSTRUMENTS, WHILE THEY TRY TO GUESS THE COORDS.

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.