|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Altitude||msl bound lower : 16000|
msl bound upper : 16500
|Controlling Facilities||tower : chs.tower|
|Operator||general aviation : personal|
|Make Model Name||Turbo Commander 690C|
|Flight Phase||cruise : level|
|Function||flight crew : single pilot|
oversight : pic
|Qualification||pilot : multi engine|
pilot : instrument
pilot : private
|Experience||flight time last 90 days : 100|
flight time total : 2300
flight time type : 275
|Anomaly||altitude deviation : excursion from assigned altitude|
inflight encounter : weather
inflight encounter : turbulence
inflight encounter other
non adherence : clearance
|Resolutory Action||controller : issued advisory|
flight crew : regained aircraft control
flight crew : returned to assigned altitude
flight crew : took evasive action
|Problem Areas||Flight Crew Human Performance|
Deviating along line (southwest-northeast) of cumulo nimbus, crossed a 'saddle' at 16000 ft on the southwest end of the line. Entered the top of a low, rapidly building cumulo nimbus. Updraft caused the plane to climb in excess of 2000 FPM in spite of 15-20 degrees nose down attitude. Unsure of total altitude deviation, but greater than 5000 ft (up). Regained control and was descending through 16300 ft for 16000 ft when center inquired as to my altitude. Another aircraft stepped on my initial transmission and I reported level at 16000 ft on the re-transmission. No further mention of the deviation was made by the controller.
Original NASA ASRS Text
Title: AC90 PLT ENCOUNTERS CUMULO NIMBUS UPDRAFT AND FIGHTS TO CTL CLB RATE AND RETURN TO ASSIGNED ALT AS ZFW CTLR REQUESTS ALT VERIFICATION.
Narrative: DEVIATING ALONG LINE (SW-NE) OF CUMULO NIMBUS, CROSSED A 'SADDLE' AT 16000 FT ON THE SW END OF THE LINE. ENTERED THE TOP OF A LOW, RAPIDLY BUILDING CUMULO NIMBUS. UPDRAFT CAUSED THE PLANE TO CLB IN EXCESS OF 2000 FPM IN SPITE OF 15-20 DEGS NOSE DOWN ATTITUDE. UNSURE OF TOTAL ALTDEV, BUT GREATER THAN 5000 FT (UP). REGAINED CTL AND WAS DSNDING THROUGH 16300 FT FOR 16000 FT WHEN CTR INQUIRED AS TO MY ALT. ANOTHER ACFT STEPPED ON MY INITIAL XMISSION AND I RPTED LEVEL AT 16000 FT ON THE RE-XMISSION. NO FURTHER MENTION OF THE DEV WAS MADE BY THE CTLR.
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.