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ZID controller observed 4 simultaneous TCASII RA's when flight crew failed to adhere to assigned crossing restr while fourth aircraft descended on a stack of 3 lower aircraft causing RA with top aircraft.
| Attributes | |
| ACN | 646385 |
| Time | |
| Date | 200501 |
| Place | |
| Locale Reference | navaid : flm.vor |
| State Reference | KY |
| Altitude | msl bound lower : 33000 msl bound upper : 36000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Dusk |
| Aircraft 1 | |
| Controlling Facilities | artcc : zid.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | A320 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : enroute altitude change |
| Flight Plan | IFR |
| Aircraft 2 | |
| Controlling Facilities | artcc : zid.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | DC-9 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Qualification | controller : radar |
| Experience | controller limited radar : 4 controller non radar : 5 controller radar : 3 controller time certified in position1 : 3 flight time total : 70 |
| ASRS Report | 646385 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met conflict : airborne critical non adherence : clearance |
| Independent Detector | atc equipment : conflict alert aircraft equipment : tcas other controllera |
| Resolutory Action | controller : issued alert controller : issued new clearance flight crew : took evasive action |
| Consequence | faa : investigated |
| Miss Distance | horizontal : 18000 vertical : 900 |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
A320 was issued crossing at FL340 and was traveling northbound. Pilot acknowledged clearance. Sector to the north of falmouth coordination that he had traffic at FL340 and requested the A320 at FL360 or FL330. I reissued a crossing to A320 to cross flm at FL330. Pilot acknowledged clearance to FL330 at flm. Then I got new traffic for A320. A320 northbound had traffic converging at flm VOR (a D39-3) sebound at FL350 and a H/B744 swbound at FL340. As A320 got close to flm; I observed that he was probably not going to make his crossing; so I asked the pilot to verify he would make the crossing. Pilot acknowledged he would make crossing. After this statement by pilot; I informed him that he had traffic north of him at FL350 and FL340. Pilot arrived over flm at FL360 and descended; which caused an RA for DC93 at FL350. The A320 answered next with an RA. DC93 descended to RA and A320 climbed to RA. The DC93's descent caused an RA with an H/B744 at FL340. Before the RA event with the H/B744; I vectored him (H/B744) when I was aware that the A320 was not going to make his crossing. I did this for safety; so targets would not merge.
Original NASA ASRS Text
Title: ZID CTLR OBSERVED 4 SIMULTANEOUS TCASII RA'S WHEN FLT CREW FAILED TO ADHERE TO ASSIGNED XING RESTR WHILE FOURTH ACFT DSNDED ON A STACK OF 3 LOWER ACFT CAUSING RA WITH TOP ACFT.
Narrative: A320 WAS ISSUED XING AT FL340 AND WAS TRAVELING NBOUND. PLT ACKNOWLEDGED CLRNC. SECTOR TO THE N OF FALMOUTH COORD THAT HE HAD TFC AT FL340 AND REQUESTED THE A320 AT FL360 OR FL330. I REISSUED A XING TO A320 TO CROSS FLM AT FL330. PLT ACKNOWLEDGED CLRNC TO FL330 AT FLM. THEN I GOT NEW TFC FOR A320. A320 NBOUND HAD TFC CONVERGING AT FLM VOR (A D39-3) SEBOUND AT FL350 AND A H/B744 SWBOUND AT FL340. AS A320 GOT CLOSE TO FLM; I OBSERVED THAT HE WAS PROBABLY NOT GOING TO MAKE HIS XING; SO I ASKED THE PLT TO VERIFY HE WOULD MAKE THE XING. PLT ACKNOWLEDGED HE WOULD MAKE XING. AFTER THIS STATEMENT BY PLT; I INFORMED HIM THAT HE HAD TFC N OF HIM AT FL350 AND FL340. PLT ARRIVED OVER FLM AT FL360 AND DSNDED; WHICH CAUSED AN RA FOR DC93 AT FL350. THE A320 ANSWERED NEXT WITH AN RA. DC93 DSNDED TO RA AND A320 CLBED TO RA. THE DC93'S DSCNT CAUSED AN RA WITH AN H/B744 AT FL340. BEFORE THE RA EVENT WITH THE H/B744; I VECTORED HIM (H/B744) WHEN I WAS AWARE THAT THE A320 WAS NOT GOING TO MAKE HIS XING. I DID THIS FOR SAFETY; SO TARGETS WOULD NOT MERGE.
Data retrieved from NASA's ASRS site as of January 2009 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.