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Potential conflict occurring as B737-200 descends to occupied altitude with opposite direction traffic. Altitude deviation altitude excursion.
| Attributes | |
| ACN | 341210 |
| Time | |
| Date | 199607 |
| Day | Mon |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : iiu |
| State Reference | KY |
| Altitude | msl bound lower : 23000 msl bound upper : 24000 |
| Environment | |
| Flight Conditions | Mixed |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zid |
| Operator | common carrier : air carrier |
| Make Model Name | B737-200 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent other |
| Flight Plan | IFR |
| Aircraft 2 | |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | other : unknown |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : flight engineer pilot : atp pilot : cfi |
| Experience | flight time last 90 days : 250 flight time total : 10000 flight time type : 4000 |
| ASRS Report | 341210 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : instrument pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 15000 flight time type : 5000 |
| ASRS Report | 341370 |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : clearance other anomaly other |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other controllera |
| Resolutory Action | controller : issued new clearance flight crew : exited adverse environment other |
| Consequence | Other |
| Miss Distance | horizontal : 24000 vertical : 1000 |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Pilot Deviation other |
Narrative:
Initially given descent clearance to 24000 ft from 31000 ft. We asked to delay descent for cloud tops. Told to stay at FL310. Later given descent to FL210. We dialed this into altitude selector, repeated clearance to ATC. As we neared FL240 I noticed a target on TCASII close to us, near our altitude. As I began to shallow descent, ATC told us to now level off at FL220, which we did, and ATC related to other aircraft that we had broken our altitude. He made no statement to us and soon switched us to another controller. We feel that ATC should listen to our own their clrncs, as we felt sure he said 'FL210, expedite,' and we repeated that. Supplemental information from acn 341370: after passing WX, the controller issued clearance to expedite to FL210. We acknowledged and started the descent. Passing FL230 the controller asked our altitude, stated we had been cleared only to FL240, but to descend now to FL220.
Original NASA ASRS Text
Title: POTENTIAL CONFLICT OCCURRING AS B737-200 DSNDS TO OCCUPIED ALT WITH OPPOSITE DIRECTION TFC. ALTDEV ALT EXCURSION.
Narrative: INITIALLY GIVEN DSCNT CLRNC TO 24000 FT FROM 31000 FT. WE ASKED TO DELAY DSCNT FOR CLOUD TOPS. TOLD TO STAY AT FL310. LATER GIVEN DSCNT TO FL210. WE DIALED THIS INTO ALT SELECTOR, REPEATED CLRNC TO ATC. AS WE NEARED FL240 I NOTICED A TARGET ON TCASII CLOSE TO US, NEAR OUR ALT. AS I BEGAN TO SHALLOW DSCNT, ATC TOLD US TO NOW LEVEL OFF AT FL220, WHICH WE DID, AND ATC RELATED TO OTHER ACFT THAT WE HAD BROKEN OUR ALT. HE MADE NO STATEMENT TO US AND SOON SWITCHED US TO ANOTHER CTLR. WE FEEL THAT ATC SHOULD LISTEN TO OUR OWN THEIR CLRNCS, AS WE FELT SURE HE SAID 'FL210, EXPEDITE,' AND WE REPEATED THAT. SUPPLEMENTAL INFO FROM ACN 341370: AFTER PASSING WX, THE CTLR ISSUED CLRNC TO EXPEDITE TO FL210. WE ACKNOWLEDGED AND STARTED THE DSCNT. PASSING FL230 THE CTLR ASKED OUR ALT, STATED WE HAD BEEN CLRED ONLY TO FL240, BUT TO DSND NOW TO FL220.
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.