 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
A departing air carrier maintaining 15000 ft receives a TCASII RA and descends to 14500 ft. Traffic was a business jet also at 15000 ft that passed within 1 mi and 500 ft. Reporter believes that an interfacility coordination problem existed between the center and departure control.
| Attributes | |
| ACN | 361760 |
| Time | |
| Date | 199702 |
| Day | Sat |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : sea |
| State Reference | WA |
| Altitude | msl bound lower : 14500 msl bound upper : 15000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other Other |
| Flight Phase | climbout : intermediate altitude cruise other |
| Route In Use | departure sid : sid enroute airway : zse |
| Flight Plan | IFR |
| Aircraft 2 | |
| Operator | general aviation : corporate |
| Make Model Name | Any Unknown or Unlisted Aircraft Manufacturer |
| Operating Under FAR Part | Part 91 |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 10000 flight time type : 3400 |
| ASRS Report | 361760 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Events | |
| Anomaly | conflict : airborne less severe non adherence : published procedure non adherence : required legal separation |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa |
| Resolutory Action | controller : issued new clearance flight crew : took evasive action other |
| Consequence | Other |
| Miss Distance | horizontal : 6000 vertical : 500 |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Operational Error |
Narrative:
Departed seatac runway 34L summa 5 departure with basically a right downwind flight path. Cleared to 9000 ft then 15000 ft. I leveled at 15000 ft and shortly we received a TCASII descend aural instruction. At the same time ZSE controller gave us clearance to a higher altitude (FL330). We told the controller we were in descent because of a TCASII RA. We reached 14500 ft when we received a 'clear of conflict' from our TCASII. I believe there was a problem with the communication between departure control and ZSE. Both aircraft were at 15000 ft level and on 2 different frequencys. Both aircraft were on IFR flight plans. I feel this is a very dangerous situation that has to be looked into. Had the situation been a little different there might have been a mid- air collision. TCASII helped save the day. At no time did the controller ever point out the small jet to us. I also think the controller was unable to clear us to a higher altitude (above 15000 ft) earlier because of another aircraft above us at 16000 ft. This is the first time my TCASII sounded between 2 IFR jet aircraft. Thanks for your time.
Original NASA ASRS Text
Title: A DEPARTING ACR MAINTAINING 15000 FT RECEIVES A TCASII RA AND DSNDS TO 14500 FT. TFC WAS A BUSINESS JET ALSO AT 15000 FT THAT PASSED WITHIN 1 MI AND 500 FT. RPTR BELIEVES THAT AN INTERFAC COORD PROB EXISTED BTWN THE CTR AND DEP CTL.
Narrative: DEPARTED SEATAC RWY 34L SUMMA 5 DEP WITH BASICALLY A R DOWNWIND FLT PATH. CLRED TO 9000 FT THEN 15000 FT. I LEVELED AT 15000 FT AND SHORTLY WE RECEIVED A TCASII DSND AURAL INSTRUCTION. AT THE SAME TIME ZSE CTLR GAVE US CLRNC TO A HIGHER ALT (FL330). WE TOLD THE CTLR WE WERE IN DSCNT BECAUSE OF A TCASII RA. WE REACHED 14500 FT WHEN WE RECEIVED A 'CLR OF CONFLICT' FROM OUR TCASII. I BELIEVE THERE WAS A PROB WITH THE COM BTWN DEP CTL AND ZSE. BOTH ACFT WERE AT 15000 FT LEVEL AND ON 2 DIFFERENT FREQS. BOTH ACFT WERE ON IFR FLT PLANS. I FEEL THIS IS A VERY DANGEROUS SIT THAT HAS TO BE LOOKED INTO. HAD THE SIT BEEN A LITTLE DIFFERENT THERE MIGHT HAVE BEEN A MID- AIR COLLISION. TCASII HELPED SAVE THE DAY. AT NO TIME DID THE CTLR EVER POINT OUT THE SMALL JET TO US. I ALSO THINK THE CTLR WAS UNABLE TO CLR US TO A HIGHER ALT (ABOVE 15000 FT) EARLIER BECAUSE OF ANOTHER ACFT ABOVE US AT 16000 FT. THIS IS THE FIRST TIME MY TCASII SOUNDED BTWN 2 IFR JET ACFT. THANKS FOR YOUR TIME.
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.