Narrative:

Checked WX (metars and taf) on internet prior to training flight involving cross country flight to klyh and return. Wind at takeoff was 280 degrees at 12 KTS. Takeoff and departure climb were normal with light to moderate turbulence. Leveled for cruise and cleared on course. A lear jet on approach to roa reported severe to extreme turbulence. I don't know the lear's position relative to roa, but suspect was north over mountainous terrain. About 30 seconds later, we encountered a brief pocket of moderate to severe turbulence over a ridge line. ATC asked us about our 'ride,' and I reported 'generally light to moderate turbulence with a brief encounter of severe,' and reported the location of severe. During the encounter, I had heard a metallic sound from the rear of the aircraft. While subsequently (about 1 min) scanning to my right for traffic I caught sight of movement in my peripheral vision and observed that the right rear window in the baggage area was broken. The damage to this apparent non-structural window was causing no adverse handling or aerodynamic result. I advised ATC that I wished to return to kroa and land. I was cleared to do so and landed without incident. That evening I contacted 'WX brief,' and asked if any airmet or SIGMET had been issued for the time of my flight and was advised that they did not retain earlier airmets, etc. I called the national WX service also, and was told that they did not know either. I should have, but did not check this before the flight. Also, I do not know if the damage might have been caused by the tow bar in the baggage compartment and/or a quart of oil also stowed there, or whether fuselage twisting caused the window to break.

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Original NASA ASRS Text

Title: CFI RPTED SEVERE TURB IN THE VICINITY OF ROA, CAUSING A BROKEN WINDOW DURING A TRAINING FLT.

Narrative: CHKED WX (METARS AND TAF) ON INTERNET PRIOR TO TRAINING FLT INVOLVING XCOUNTRY FLT TO KLYH AND RETURN. WIND AT TKOF WAS 280 DEGS AT 12 KTS. TKOF AND DEP CLB WERE NORMAL WITH LIGHT TO MODERATE TURB. LEVELED FOR CRUISE AND CLRED ON COURSE. A LEAR JET ON APCH TO ROA RPTED SEVERE TO EXTREME TURB. I DON'T KNOW THE LEAR'S POS RELATIVE TO ROA, BUT SUSPECT WAS N OVER MOUNTAINOUS TERRAIN. ABOUT 30 SECONDS LATER, WE ENCOUNTERED A BRIEF POCKET OF MODERATE TO SEVERE TURB OVER A RIDGE LINE. ATC ASKED US ABOUT OUR 'RIDE,' AND I RPTED 'GENERALLY LIGHT TO MODERATE TURB WITH A BRIEF ENCOUNTER OF SEVERE,' AND RPTED THE LOCATION OF SEVERE. DURING THE ENCOUNTER, I HAD HEARD A METALLIC SOUND FROM THE REAR OF THE ACFT. WHILE SUBSEQUENTLY (ABOUT 1 MIN) SCANNING TO MY R FOR TFC I CAUGHT SIGHT OF MOVEMENT IN MY PERIPHERAL VISION AND OBSERVED THAT THE R REAR WINDOW IN THE BAGGAGE AREA WAS BROKEN. THE DAMAGE TO THIS APPARENT NON-STRUCTURAL WINDOW WAS CAUSING NO ADVERSE HANDLING OR AERODYNAMIC RESULT. I ADVISED ATC THAT I WISHED TO RETURN TO KROA AND LAND. I WAS CLRED TO DO SO AND LANDED WITHOUT INCIDENT. THAT EVENING I CONTACTED 'WX BRIEF,' AND ASKED IF ANY AIRMET OR SIGMET HAD BEEN ISSUED FOR THE TIME OF MY FLT AND WAS ADVISED THAT THEY DID NOT RETAIN EARLIER AIRMETS, ETC. I CALLED THE NATIONAL WX SVC ALSO, AND WAS TOLD THAT THEY DID NOT KNOW EITHER. I SHOULD HAVE, BUT DID NOT CHK THIS BEFORE THE FLT. ALSO, I DO NOT KNOW IF THE DAMAGE MIGHT HAVE BEEN CAUSED BY THE TOW BAR IN THE BAGGAGE COMPARTMENT AND/OR A QUART OF OIL ALSO STOWED THERE, OR WHETHER FUSELAGE TWISTING CAUSED THE WINDOW TO BREAK.

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.