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|
Attributes | |
ACN | 261022 |
Time | |
Date | 199401 |
Day | Fri |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | atc facility : svm |
State Reference | MI |
Altitude | msl bound lower : 18000 msl bound upper : 25000 |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zob tower : pit |
Operator | common carrier : air carrier |
Make Model Name | DC-9 30 |
Operating Under FAR Part | Part 121 |
Flight Phase | climbout : intermediate altitude |
Route In Use | enroute : on vectors |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : flight engineer pilot : instrument pilot : commercial pilot : atp |
Experience | flight time last 90 days : 180 flight time total : 18000 flight time type : 10000 |
ASRS Report | 261022 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : commercial pilot : instrument |
Events | |
Anomaly | conflict : airborne less severe inflight encounter other non adherence : clearance other anomaly other anomaly other anomaly other |
Independent Detector | other controllera other flight crewa |
Resolutory Action | flight crew : exited adverse environment flight crew : regained aircraft control other |
Consequence | Other |
Supplementary | |
Primary Problem | Weather |
Air Traffic Incident | Pilot Deviation |
Narrative:
ATC had assigned 250 KTS on climb out from dtw due to traffic ahead of us. Passing through FL180 (we were assigned FL280) we passed through a cold front and encountered a windshear with severe turbulence resulting in a sudden increase of airspeed (to plus or minus 300 KTS) and rate of climb while on the autoplt. I disconnected the autoplt, increased pitch and reduced power trying to maintain turbulent airspeed va (285 KTS), hoping to find smooth air at a higher altitude. ATC voiced some concern of our airspeed and conflict with traffic ahead while being very upset with our airspeed increase, claimed we had a 100 KT closure. Passing 22300 ft ATC demanded that we level off at FL230 and do a tight 90 degree turn off course. It took everything we had to just control the aircraft in the turbulence while trying to level off and turn and slow down. TCASII never did go off, so we never did know just how close we came to traffic ahead. Later we were told that the winds were 180 degrees out across front and winds reported at 135 KTS at that altitude. Later, after being reassigned to climb to FL310, we encountered shortly after breaking out (FL250?) on top the reverse wind shear with loss of airspeed and rate of climb dropping to '0.' the front was visible later on climb and had a sharp line of definition with clouds looking like a 25000 ft wall on one side, clear on the other side. I never did find out how much of a temperature and pressure difference there was across the front to cause such an upset. (I.e., our DC9-30 was pwred with big engines, -15's, and we had only a medium weight/load. I guess I never gave wind shear at altitude much thought before, until now.
Original NASA ASRS Text
Title: SPD RESTR NOT ADHERED TO IN FLC DEV. SPD DEV.
Narrative: ATC HAD ASSIGNED 250 KTS ON CLBOUT FROM DTW DUE TO TFC AHEAD OF US. PASSING THROUGH FL180 (WE WERE ASSIGNED FL280) WE PASSED THROUGH A COLD FRONT AND ENCOUNTERED A WINDSHEAR WITH SEVERE TURB RESULTING IN A SUDDEN INCREASE OF AIRSPD (TO PLUS OR MINUS 300 KTS) AND RATE OF CLB WHILE ON THE AUTOPLT. I DISCONNECTED THE AUTOPLT, INCREASED PITCH AND REDUCED PWR TRYING TO MAINTAIN TURBULENT AIRSPD VA (285 KTS), HOPING TO FIND SMOOTH AIR AT A HIGHER ALT. ATC VOICED SOME CONCERN OF OUR AIRSPD AND CONFLICT WITH TFC AHEAD WHILE BEING VERY UPSET WITH OUR AIRSPD INCREASE, CLAIMED WE HAD A 100 KT CLOSURE. PASSING 22300 FT ATC DEMANDED THAT WE LEVEL OFF AT FL230 AND DO A TIGHT 90 DEG TURN OFF COURSE. IT TOOK EVERYTHING WE HAD TO JUST CTL THE ACFT IN THE TURB WHILE TRYING TO LEVEL OFF AND TURN AND SLOW DOWN. TCASII NEVER DID GO OFF, SO WE NEVER DID KNOW JUST HOW CLOSE WE CAME TO TFC AHEAD. LATER WE WERE TOLD THAT THE WINDS WERE 180 DEGS OUT ACROSS FRONT AND WINDS RPTED AT 135 KTS AT THAT ALT. LATER, AFTER BEING REASSIGNED TO CLB TO FL310, WE ENCOUNTERED SHORTLY AFTER BREAKING OUT (FL250?) ON TOP THE REVERSE WIND SHEAR WITH LOSS OF AIRSPD AND RATE OF CLB DROPPING TO '0.' THE FRONT WAS VISIBLE LATER ON CLB AND HAD A SHARP LINE OF DEFINITION WITH CLOUDS LOOKING LIKE A 25000 FT WALL ON ONE SIDE, CLR ON THE OTHER SIDE. I NEVER DID FIND OUT HOW MUCH OF A TEMP AND PRESSURE DIFFERENCE THERE WAS ACROSS THE FRONT TO CAUSE SUCH AN UPSET. (I.E., OUR DC9-30 WAS PWRED WITH BIG ENGS, -15'S, AND WE HAD ONLY A MEDIUM WT/LOAD. I GUESS I NEVER GAVE WIND SHEAR AT ALT MUCH THOUGHT BEFORE, UNTIL NOW.
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.