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An large transport freighter crew, at night, in thunderstorms, stopped their descent on a pilot's discretion descent to avoid a build up.
| Attributes | |
| ACN | 217244 |
| Time | |
| Date | 199207 |
| Day | Fri |
| Local Time Of Day | 0001 To 0600 |
| Place | |
| Locale Reference | atc facility : iiu |
| State Reference | KY |
| Altitude | msl bound lower : 25000 msl bound upper : 29000 |
| Environment | |
| Flight Conditions | Mixed |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | artcc : zid |
| Operator | common carrier : air carrier |
| Make Model Name | Large Transport, Low Wing, 2 Turbojet Eng |
| Navigation In Use | Other Other |
| Flight Phase | descent other |
| Route In Use | arrival other enroute other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp pilot : instrument pilot : commercial |
| Experience | flight time last 90 days : 300 flight time total : 9000 flight time type : 500 |
| ASRS Report | 217244 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial |
| Experience | flight time last 90 days : 150 flight time total : 4500 |
| ASRS Report | 217754 |
| Events | |
| Anomaly | altitude deviation : undershoot inflight encounter : weather non adherence : far other anomaly other |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa |
| Resolutory Action | flight crew : exited adverse environment flight crew : returned to intended course or assigned course flight crew : took evasive action |
| Consequence | faa : investigated |
| Supplementary | |
| Primary Problem | Weather |
| Air Traffic Incident | Pilot Deviation other |
Narrative:
In IMC conditions, with clearance to descend from FL290 to FL240 (at pilot's discretion) I stopped descent at FL270. As I broke out of an overcast layer. I was immediately confronted by a thunderstorm (not showing on the radar) and climbed to FL27.5 to avoid it. ZID asked about our altitude. I said we had climbed to avoid a thunderstorm. He said something else about the altitude and I replied that I was declaring an emergency to avoid the thunderstorm. A couple of mins later he asked if the emergency was over and I said yes. No other discussion occurred about the altitude deviation. Also, I forgot to mention we were deviating for WX at the time. After the flight I called ZID and spoke with the shift supervisor about this. He said that the controller had not said anything about it to him and that it apparently was not a problem. I gave him my name and he said that if there was a problem he would call me. I have not heard from him. Supplemental information from acn 217754. Just below FL270 we encountered a layer of clear air and the captain elected to level there, but just ahead could see that the clouds were beginning to rise. At that instant a flash of lightning was observed in the clouds. The captain turned off the autoplt and simultaneously began a climb to avoid the clouds and call to ATC to advise them of the climb. ATC replied with a 'negative we have traffic descending over you.' the captain then replied 'we'll have to declare an emergency then.' at this point we had climbed about 300 ft and turned slightly left of course, and found ourselves in the clear. When ATC again inquired about the emergency, the captain stated that all was ok again.
Original NASA ASRS Text
Title: AN LGT FREIGHTER CREW, AT NIGHT, IN TSTMS, STOPPED THEIR DSCNT ON A PLT'S DISCRETION DSCNT TO AVOID A BUILD UP.
Narrative: IN IMC CONDITIONS, WITH CLRNC TO DSND FROM FL290 TO FL240 (AT PLT'S DISCRETION) I STOPPED DSCNT AT FL270. AS I BROKE OUT OF AN OVCST LAYER. I WAS IMMEDIATELY CONFRONTED BY A TSTM (NOT SHOWING ON THE RADAR) AND CLBED TO FL27.5 TO AVOID IT. ZID ASKED ABOUT OUR ALT. I SAID WE HAD CLBED TO AVOID A TSTM. HE SAID SOMETHING ELSE ABOUT THE ALT AND I REPLIED THAT I WAS DECLARING AN EMER TO AVOID THE TSTM. A COUPLE OF MINS LATER HE ASKED IF THE EMER WAS OVER AND I SAID YES. NO OTHER DISCUSSION OCCURRED ABOUT THE ALTDEV. ALSO, I FORGOT TO MENTION WE WERE DEVIATING FOR WX AT THE TIME. AFTER THE FLT I CALLED ZID AND SPOKE WITH THE SHIFT SUPVR ABOUT THIS. HE SAID THAT THE CTLR HAD NOT SAID ANYTHING ABOUT IT TO HIM AND THAT IT APPARENTLY WAS NOT A PROBLEM. I GAVE HIM MY NAME AND HE SAID THAT IF THERE WAS A PROBLEM HE WOULD CALL ME. I HAVE NOT HEARD FROM HIM. SUPPLEMENTAL INFO FROM ACN 217754. JUST BELOW FL270 WE ENCOUNTERED A LAYER OF CLR AIR AND THE CAPT ELECTED TO LEVEL THERE, BUT JUST AHEAD COULD SEE THAT THE CLOUDS WERE BEGINNING TO RISE. AT THAT INSTANT A FLASH OF LIGHTNING WAS OBSERVED IN THE CLOUDS. THE CAPT TURNED OFF THE AUTOPLT AND SIMULTANEOUSLY BEGAN A CLB TO AVOID THE CLOUDS AND CALL TO ATC TO ADVISE THEM OF THE CLB. ATC REPLIED WITH A 'NEGATIVE WE HAVE TFC DSNDING OVER YOU.' THE CAPT THEN REPLIED 'WE'LL HAVE TO DECLARE AN EMER THEN.' AT THIS POINT WE HAD CLBED ABOUT 300 FT AND TURNED SLIGHTLY L OF COURSE, AND FOUND OURSELVES IN THE CLR. WHEN ATC AGAIN INQUIRED ABOUT THE EMER, THE CAPT STATED THAT ALL WAS OK AGAIN.
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.