 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Wave action over the top of a thunderstorm caused up to 1000 foot deviation from assigned altitude that was not noted by ATC and was not reported by the pilot in command, even though the second in command advocated for a report.
| Attributes | |
| ACN | 506080 |
| Time | |
| Date | 200103 |
| Day | Thu |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : zjx.artcc |
| State Reference | FL |
| Altitude | msl single value : 41000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : charter |
| Make Model Name | Light Transport, Low Wing, 2 Turbojet Eng |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : charter |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 111 flight time total : 3200 flight time type : 300 |
| ASRS Report | 506080 |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude inflight encounter : turbulence non adherence : clearance other anomaly other other anomaly other |
| Resolutory Action | flight crew : returned to assigned altitude |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Weather |
| Primary Problem | Weather |
Narrative:
During flight at FL410, aircraft flew over top of thunderstorm. As aircraft approached top (clear above), aircraft encountered strong updraft causing aircraft altimeter to climb to FL41900-42000. Aircraft power levers were reduced to almost idle and pitch lowered in order to re-establish FL410. As soon as aircraft passed thunderstorm, altitude was re-established. Nothing was said by ATC. Flight continued to destination without further incident. During the rapid climb, autoplt was engaged with altitude select at 41000FT. Autoplt was disengaged in order to recover altitude, then re-engaged after being re-established. Co-pilot suggested to captain to notify ATC of altitude climb but no action was taken.
Original NASA ASRS Text
Title: WAVE ACTION OVER THE TOP OF A THUNDERSTORM CAUSED UP TO 1000 FOOT DEVIATION FROM ASSIGNED ALT THAT WAS NOT NOTED BY ATC AND WAS NOT RPTED BY THE PLT IN COMMAND, EVEN THOUGH THE SECOND IN COMMAND ADVOCATED FOR A RPT.
Narrative: DURING FLT AT FL410, ACFT FLEW OVER TOP OF THUNDERSTORM. AS ACFT APCHED TOP (CLR ABOVE), ACFT ENCOUNTERED STRONG UPDRAFT CAUSING ACFT ALTIMETER TO CLB TO FL41900-42000. ACFT PWR LEVERS WERE REDUCED TO ALMOST IDLE AND PITCH LOWERED IN ORDER TO RE-ESTABLISH FL410. AS SOON AS ACFT PASSED THUNDERSTORM, ALT WAS RE-ESTABLISHED. NOTHING WAS SAID BY ATC. FLT CONTINUED TO DESTINATION WITHOUT FURTHER INCIDENT. DURING THE RAPID CLIMB, AUTOPLT WAS ENGAGED WITH ALT SELECT AT 41000FT. AUTOPLT WAS DISENGAGED IN ORDER TO RECOVER ALT, THEN RE-ENGAGED AFTER BEING RE-ESTABLISHED. CO-PLT SUGGESTED TO CAPT TO NOTIFY ATC OF ALT CLB BUT NO ACTION WAS TAKEN.
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.