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An air carrier twin jet flight crew fails to make a late descent clearance crossing altitude in proximity of thunderstorm activity 10 mi west of ldn, va.
| Attributes | |
| ACN | 475840 |
| Time | |
| Date | 200006 |
| Day | Mon |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| State Reference | LA |
| Altitude | msl bound lower : 11000 msl bound upper : 13000 |
| Environment | |
| Flight Conditions | IMC |
| Weather Elements | Thunderstorm Turbulence |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zdc.artcc tower : lax.tower |
| Operator | common carrier : air carrier |
| Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent : vacating altitude |
| Route In Use | arrival : on vectors arrival star : jasen |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial pilot : multi engine |
| Experience | flight time last 90 days : 120 flight time total : 12000 |
| ASRS Report | 475840 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 4500 |
| ASRS Report | 475841 |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met altitude deviation : undershoot inflight encounter : turbulence inflight encounter : weather non adherence : clearance non adherence : published procedure other anomaly other anomaly other |
| Independent Detector | other flight crewa other flight crewb |
| Resolutory Action | none taken : anomaly accepted |
| Consequence | faa : reviewed incident with flight crew |
| Supplementary | |
| Problem Areas | Weather ATC Human Performance Aircraft Airspace Structure Flight Crew Human Performance |
| Primary Problem | Weather |
| Air Traffic Incident | Pilot Deviation |
Narrative:
We were at FL200 direct to ldn on the jasen 1 arrival to iad airport. We received a clearance to cross 10 mi west of ldn at 11000 ft and 250 KTS. This clearance was given when we were 25 mi west of ldn VOR. The captain began an immediate descent at idle power and the speed brakes deployed to attain the maximum rate of descent. It was immediately apparent that the crossing restr was not readable (11000 ft and 250 KTS) so ATC told us to ignore the 250 KT restr. There were thunderstorms on both sides and the option of turning was not available. There was a great deal of radio congestion. We chose to try our best to make the crossing restr. We were at 13000 ft at the crossing restr fix, instead of our assigned 11000 ft. The controller asked our altitude when we were at the crossing fix and I responded '13000 ft and descending.' the controller replied 'good' and turned us over to approach control. I feel we should have been given more time to make the crossing restr. I believe that we chose the safest course of action under the circumstances. Supplemental information from acn 475841: the controller was busy and there was a lot of radio congestion.
Original NASA ASRS Text
Title: AN ACR TWIN JET FLC FAILS TO MAKE A LATE DSCNT CLRNC XING ALT IN PROX OF TSTM ACTIVITY 10 MI W OF LDN, VA.
Narrative: WE WERE AT FL200 DIRECT TO LDN ON THE JASEN 1 ARR TO IAD ARPT. WE RECEIVED A CLRNC TO CROSS 10 MI W OF LDN AT 11000 FT AND 250 KTS. THIS CLRNC WAS GIVEN WHEN WE WERE 25 MI W OF LDN VOR. THE CAPT BEGAN AN IMMEDIATE DSCNT AT IDLE PWR AND THE SPD BRAKES DEPLOYED TO ATTAIN THE MAX RATE OF DSCNT. IT WAS IMMEDIATELY APPARENT THAT THE XING RESTR WAS NOT READABLE (11000 FT AND 250 KTS) SO ATC TOLD US TO IGNORE THE 250 KT RESTR. THERE WERE TSTMS ON BOTH SIDES AND THE OPTION OF TURNING WAS NOT AVAILABLE. THERE WAS A GREAT DEAL OF RADIO CONGESTION. WE CHOSE TO TRY OUR BEST TO MAKE THE XING RESTR. WE WERE AT 13000 FT AT THE XING RESTR FIX, INSTEAD OF OUR ASSIGNED 11000 FT. THE CTLR ASKED OUR ALT WHEN WE WERE AT THE XING FIX AND I RESPONDED '13000 FT AND DSNDING.' THE CTLR REPLIED 'GOOD' AND TURNED US OVER TO APCH CTL. I FEEL WE SHOULD HAVE BEEN GIVEN MORE TIME TO MAKE THE XING RESTR. I BELIEVE THAT WE CHOSE THE SAFEST COURSE OF ACTION UNDER THE CIRCUMSTANCES. SUPPLEMENTAL INFO FROM ACN 475841: THE CTLR WAS BUSY AND THERE WAS A LOT OF RADIO CONGESTION.
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.