 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
B717 captain experiences a TCAS RA at FL320 due to a citation that did not level off at FL300 as assigned. Autopilot vertical speed is used to comply with the RA.
| Attributes | |
| ACN | 1068268 |
| Time | |
| Date | 201302 |
| Local Time Of Day | 0001-0600 |
| Place | |
| Locale Reference | ZDC.ARTCC |
| State Reference | VA |
| Environment | |
| Flight Conditions | VMC |
| Aircraft 1 | |
| Make Model Name | B717 (Formerly MD-95) |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Cruise |
| Flight Plan | IFR |
| Person 1 | |
| Function | Captain Pilot Flying |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Events | |
| Anomaly | Conflict Airborne Conflict Deviation - Altitude Excursion From Assigned Altitude |
| Miss Distance | Horizontal 3000 Vertical 500 |
Narrative:
When the incident began I heard ATC telling a cessna citation to level immediately at FL310. We were in level cruise at FL320 and I had no knowledge of the cessna citation's position. Right after I heard this transmission; the TCAS issued a TA and then a climb RA. I immediately used the vertical speed to put the aircraft in a climb. The commanded climb was about 1;500 FPM. I looked out the window and saw a straight wing cessna citation in front of us below and slightly to the left. I told the first officer to advise ATC that we were in a 'TCAS climb.' he did this. At FL325 the TCAS changed from a commanded climb to 'monitor vertical speed' and I reduced the vs to 0. Shortly thereafter the TCAS issued a 'clear of conflict' and I used the vertical speed to return to our assigned altitude. We advised ATC that we had returned to our previously assigned altitude of FL320. I saw a minimum vertical separation of -800 feet but the first officer stated that he saw -500 feet. I'm guessing that we were about 1/2 mile behind the citation. ATC stated that the citation was supposed to level at FL300. We sent messages to dispatch describing the event.
Original NASA ASRS Text
Title: B717 Captain experiences a TCAS RA at FL320 due to a Citation that did not level off at FL300 as assigned. Autopilot vertical speed is used to comply with the RA.
Narrative: When the incident began I heard ATC telling a Cessna Citation to level immediately at FL310. We were in level cruise at FL320 and I had no knowledge of the Cessna Citation's position. Right after I heard this transmission; the TCAS issued a TA and then a climb RA. I immediately used the vertical speed to put the aircraft in a climb. The commanded climb was about 1;500 FPM. I looked out the window and saw a straight wing Cessna Citation in front of us below and slightly to the left. I told the FO to advise ATC that we were in a 'TCAS climb.' He did this. AT FL325 the TCAS changed from a commanded climb to 'Monitor vertical speed' and I reduced the VS to 0. Shortly thereafter the TCAS issued a 'Clear of Conflict' and I used the vertical speed to return to our assigned altitude. We advised ATC that we had returned to our previously assigned altitude of FL320. I saw a minimum vertical separation of -800 feet but the FO stated that he saw -500 feet. I'm guessing that we were about 1/2 mile behind the Citation. ATC stated that the Citation was supposed to level at FL300. We sent messages to dispatch describing the event.
Data retrieved from NASA's ASRS site as of July 2013 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.