Narrative:

On a VFR flight from schenectady, ny, to chester, ct, a decision was made, based on reported WX, to proceed over the mountains on top of a scattered to broken layer. Conditions east of the mountains were reported at 3000' scattered, 12000' overcast, 6+. Climbs from 5500 to 7500', and then to 9500' were necessary to remain clear of clouds. Tops were at about 7000' with visibility at 9500' at greater than 10 mi. Bradley approach was being monitored with the intention of calling VFR advisory service at about 25 mi from bradley, my normal procedure even though well above and outside the arsa. Radio traffic was heavy, so I delayed calling. (Squawking 1200 and mode C.) when southwest of bradley at about 18 mi, course about 150 on a bearing of 060 degrees (to my 9 O'clock position) and about 6 mi, a commercial jet appeared, apparently just climbing out of the overcast. I initiated a right turn, as did the jet. Closest approach I estimated at 3 mi or so. The jet continued its climb and I resumed course as soon as we were clear. Point to be made: a jet climbing at perhaps 200 KTS and 2000 FPM covers 3 mi in 2000' of climb. Potentially at an apparently safe distance above clouds of 2000+', it is possible to have only 1 min to respond to a jet climbing out through the clouds. When flying VFR on top of a broken or overcast layer, within 25 mi of an airport with jet traffic, be sure contact is made with approach control by requesting VFR advisories. If unable, then skirt the area by 25 mi minimum. This occurred at a position which coincides with a straight climb out from the probable active at bradley, runway 24, but not all clbouts are straight out, so all directions are potential conflict areas, as I estimate, to about 25 mi.

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Original NASA ASRS Text

Title: CPR-SMA IS SURPRISED BY AN ACR-MLG CLIMBING RAPIDLY OUT OF THE UNDERCAST.

Narrative: ON A VFR FLT FROM SCHENECTADY, NY, TO CHESTER, CT, A DECISION WAS MADE, BASED ON RPTED WX, TO PROCEED OVER THE MOUNTAINS ON TOP OF A SCATTERED TO BROKEN LAYER. CONDITIONS E OF THE MOUNTAINS WERE RPTED AT 3000' SCATTERED, 12000' OVCST, 6+. CLBS FROM 5500 TO 7500', AND THEN TO 9500' WERE NECESSARY TO REMAIN CLR OF CLOUDS. TOPS WERE AT ABOUT 7000' WITH VISIBILITY AT 9500' AT GREATER THAN 10 MI. BRADLEY APCH WAS BEING MONITORED WITH THE INTENTION OF CALLING VFR ADVISORY SVC AT ABOUT 25 MI FROM BRADLEY, MY NORMAL PROC EVEN THOUGH WELL ABOVE AND OUTSIDE THE ARSA. RADIO TFC WAS HVY, SO I DELAYED CALLING. (SQUAWKING 1200 AND MODE C.) WHEN SW OF BRADLEY AT ABOUT 18 MI, COURSE ABOUT 150 ON A BEARING OF 060 DEGS (TO MY 9 O'CLOCK POS) AND ABOUT 6 MI, A COMMERCIAL JET APPEARED, APPARENTLY JUST CLBING OUT OF THE OVCST. I INITIATED A RIGHT TURN, AS DID THE JET. CLOSEST APCH I ESTIMATED AT 3 MI OR SO. THE JET CONTINUED ITS CLB AND I RESUMED COURSE AS SOON AS WE WERE CLR. POINT TO BE MADE: A JET CLBING AT PERHAPS 200 KTS AND 2000 FPM COVERS 3 MI IN 2000' OF CLB. POTENTIALLY AT AN APPARENTLY SAFE DISTANCE ABOVE CLOUDS OF 2000+', IT IS POSSIBLE TO HAVE ONLY 1 MIN TO RESPOND TO A JET CLBING OUT THROUGH THE CLOUDS. WHEN FLYING VFR ON TOP OF A BROKEN OR OVCST LAYER, WITHIN 25 MI OF AN ARPT WITH JET TFC, BE SURE CONTACT IS MADE WITH APCH CTL BY REQUESTING VFR ADVISORIES. IF UNABLE, THEN SKIRT THE AREA BY 25 MI MINIMUM. THIS OCCURRED AT A POS WHICH COINCIDES WITH A STRAIGHT CLBOUT FROM THE PROBABLE ACTIVE AT BRADLEY, RWY 24, BUT NOT ALL CLBOUTS ARE STRAIGHT OUT, SO ALL DIRECTIONS ARE POTENTIAL CONFLICT AREAS, AS I ESTIMATE, TO ABOUT 25 MI.

Data retrieved from NASA's ASRS site as of August 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.