Narrative:

I am a cfii who was taking an instrument student out for a lesson in basic attitude instrument flying in an IFR equipped PA28 archer. Smooth air would be preferable, and there were some cumulus clouds above fws airport the morning of the event, so I wanted to climb through the breaks and get above the clouds if possible. The FBO's WX radar showed no precipitation, and visually there appeared to be significant holes between the areas of cloud coverage. We launched and I put the student under the hood during climb out. In the climb out I found cloud bases were about 2500 ft MSL as I vectored the student through major gaps in the clouds looking for a big hole or to get on top. At 3500 ft MSL we were on top of nearly everything and I elected to have the student climb to 4500 ft for proper VFR cloud clearance. As we continued climbing southwest from fws the clouds seemed to be getting higher and the gaps closed in a bit. Once level at 4500 ft I looked around for a cloud-free area large enough to do our air work. To the west I saw what appeared to be an area of either clear air or simply lower cloud tops, so I vectored the student around one last cloud in that direction. As we rounded the corner a part of the cloud not previously visible was there to meet us and other clouds were suddenly so close as to preclude a course reversal using a standard rate turn. The student rolled out on the heading I had assigned and we entered the cloud. I had the student hold heading for a min or so thinking such an action was preferable because I had previously seen clear air very close in this direction. When we did not clear the cloud in a min or so, I found a hole downward, took the airplane and descended rapidly through the hole until we were in the clear and at least 500 ft below the clouds at 2200 ft MSL. We continued the attitude instrument flying lesson, and as part of the lesson I discussed with the student the mistake I had made and the necessity to have a clearance before entering IMC. I also applauded him for flying a pretty good airplane while I was searching for a suitable clear area large enough for more than just straight and level practice. My basic mistake was allowing a VFR flight to continue into worsening conditions. Though aircraft control and a safe outcome to the flight were never in doubt in my judgement, perhaps my judgement could stand some refining. This has been a rather large slice of humble pie.

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Original NASA ASRS Text

Title: PA28 INSTRUCTOR TAKES STUDENT OUT INTO BROKEN CLOUD CONDITION AND ENCOUNTERS IMC WHILE FLYING VFR.

Narrative: I AM A CFII WHO WAS TAKING AN INST STUDENT OUT FOR A LESSON IN BASIC ATTITUDE INST FLYING IN AN IFR EQUIPPED PA28 ARCHER. SMOOTH AIR WOULD BE PREFERABLE, AND THERE WERE SOME CUMULUS CLOUDS ABOVE FWS ARPT THE MORNING OF THE EVENT, SO I WANTED TO CLB THROUGH THE BREAKS AND GET ABOVE THE CLOUDS IF POSSIBLE. THE FBO'S WX RADAR SHOWED NO PRECIPITATION, AND VISUALLY THERE APPEARED TO BE SIGNIFICANT HOLES BTWN THE AREAS OF CLOUD COVERAGE. WE LAUNCHED AND I PUT THE STUDENT UNDER THE HOOD DURING CLBOUT. IN THE CLBOUT I FOUND CLOUD BASES WERE ABOUT 2500 FT MSL AS I VECTORED THE STUDENT THROUGH MAJOR GAPS IN THE CLOUDS LOOKING FOR A BIG HOLE OR TO GET ON TOP. AT 3500 FT MSL WE WERE ON TOP OF NEARLY EVERYTHING AND I ELECTED TO HAVE THE STUDENT CLB TO 4500 FT FOR PROPER VFR CLOUD CLRNC. AS WE CONTINUED CLBING SW FROM FWS THE CLOUDS SEEMED TO BE GETTING HIGHER AND THE GAPS CLOSED IN A BIT. ONCE LEVEL AT 4500 FT I LOOKED AROUND FOR A CLOUD-FREE AREA LARGE ENOUGH TO DO OUR AIR WORK. TO THE W I SAW WHAT APPEARED TO BE AN AREA OF EITHER CLR AIR OR SIMPLY LOWER CLOUD TOPS, SO I VECTORED THE STUDENT AROUND ONE LAST CLOUD IN THAT DIRECTION. AS WE ROUNDED THE CORNER A PART OF THE CLOUD NOT PREVIOUSLY VISIBLE WAS THERE TO MEET US AND OTHER CLOUDS WERE SUDDENLY SO CLOSE AS TO PRECLUDE A COURSE REVERSAL USING A STANDARD RATE TURN. THE STUDENT ROLLED OUT ON THE HEADING I HAD ASSIGNED AND WE ENTERED THE CLOUD. I HAD THE STUDENT HOLD HEADING FOR A MIN OR SO THINKING SUCH AN ACTION WAS PREFERABLE BECAUSE I HAD PREVIOUSLY SEEN CLR AIR VERY CLOSE IN THIS DIRECTION. WHEN WE DID NOT CLR THE CLOUD IN A MIN OR SO, I FOUND A HOLE DOWNWARD, TOOK THE AIRPLANE AND DSNDED RAPIDLY THROUGH THE HOLE UNTIL WE WERE IN THE CLR AND AT LEAST 500 FT BELOW THE CLOUDS AT 2200 FT MSL. WE CONTINUED THE ATTITUDE INST FLYING LESSON, AND AS PART OF THE LESSON I DISCUSSED WITH THE STUDENT THE MISTAKE I HAD MADE AND THE NECESSITY TO HAVE A CLRNC BEFORE ENTERING IMC. I ALSO APPLAUDED HIM FOR FLYING A PRETTY GOOD AIRPLANE WHILE I WAS SEARCHING FOR A SUITABLE CLR AREA LARGE ENOUGH FOR MORE THAN JUST STRAIGHT AND LEVEL PRACTICE. MY BASIC MISTAKE WAS ALLOWING A VFR FLT TO CONTINUE INTO WORSENING CONDITIONS. THOUGH ACFT CTL AND A SAFE OUTCOME TO THE FLT WERE NEVER IN DOUBT IN MY JUDGEMENT, PERHAPS MY JUDGEMENT COULD STAND SOME REFINING. THIS HAS BEEN A RATHER LARGE SLICE OF HUMBLE PIE.

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.