B757 operating in class two airspace over the pacific encountered severe turbulence, utilized emergency authority/authorized to offset from course and descend.

Home

Browse by month

Random

Latest

About

Contact

Attributes
ACN	579731
Time
Date	200304
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zoa.artcc
State Reference	CA
Altitude	msl bound lower : 31500 msl bound upper : 33000
Environment
Weather Elements	Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa.artcc tower : owb.tower
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : level
Route In Use	enroute : pacific
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer oversight : pic
ASRS Report	579731
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : turbulence non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllera other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : declared emergency flight crew : exited adverse environment other
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Environmental Factor ATC Human Performance Weather
Primary Problem	Environmental Factor

Narrative:

Location: derok, mid pacific. On course, on altitude, FL330 near derok. Encountered increasing turbulence from moderate to severe. Requested lower altitude 4 times over 20 mins. Told unable due to traffic. Decided to turn off track and parallel at 10 mi and descend to FL315 where turbulence abated. Sfo asked our position and cleared us to offset 60 mi north of track then cleared to FL310 and reclred onto track. Asked if deviation was due to emergency condition. We said, 'yes due to severe turbulence.'

Original NASA ASRS Text

Title: B757 OPERATING IN CLASS TWO AIRSPACE OVER THE PACIFIC ENCOUNTERED SEVERE TURB, UTILIZED EMER AUTH TO OFFSET FROM COURSE AND DSND.

Narrative: LOCATION: DEROK, MID PACIFIC. ON COURSE, ON ALT, FL330 NEAR DEROK. ENCOUNTERED INCREASING TURB FROM MODERATE TO SEVERE. REQUESTED LOWER ALT 4 TIMES OVER 20 MINS. TOLD UNABLE DUE TO TFC. DECIDED TO TURN OFF TRACK AND PARALLEL AT 10 MI AND DSND TO FL315 WHERE TURB ABATED. SFO ASKED OUR POS AND CLRED US TO OFFSET 60 MI N OF TRACK THEN CLRED TO FL310 AND RECLRED ONTO TRACK. ASKED IF DEV WAS DUE TO EMER CONDITION. WE SAID, 'YES DUE TO SEVERE TURB.'

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.