 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Potential conflict, a system error, occurs when 2 air carrier aircraft are assigned the same wbound altitude of FL310, one aircraft eastbound, the other swbound.
| Attributes | |
| ACN | 416960 |
| Time | |
| Date | 199810 |
| Day | Tue |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : ape |
| State Reference | OH |
| Altitude | msl bound lower : 31000 msl bound upper : 31000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zid |
| Operator | common carrier : air carrier |
| Make Model Name | Large Transport, Low Wing, 3 Turbojet Eng |
| Flight Phase | cruise other |
| Route In Use | enroute : direct enroute : on vectors |
| Flight Plan | IFR |
| Aircraft 2 | |
| Operator | common carrier : air carrier |
| Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp pilot : instrument |
| Experience | flight time last 90 days : 186 flight time total : 14000 flight time type : 7000 |
| ASRS Report | 416960 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp pilot : flight engineer |
| Experience | flight time last 90 days : 190 flight time total : 6300 flight time type : 1628 |
| ASRS Report | 416802 |
| Events | |
| Anomaly | conflict : airborne less severe non adherence : required legal separation non adherence : published procedure other anomaly other |
| Independent Detector | atc equipment other atc equipment : unspecified aircraft equipment other aircraft equipment : unspecified |
| Resolutory Action | controller : issued new clearance other |
| Consequence | faa : investigated |
| Miss Distance | horizontal : 26400 vertical : 0 |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Operational Error |
Narrative:
En route from cmh to atl on heading of 190 degrees magnetic until reading odf, then direct, level at FL310 assigned altitude, ZID gave us a right turn to heading 270 degrees magnetic. As we were in the turn, TCASII advised 'traffic, traffic' and I observed target at 9 O'clock, 5 mi, our altitude. Center asked our assigned altitude. I replied FL310. Center called other aircraft and gave a turn to 180 degrees magnetic. Aircraft separation appeared to maintain at 5 NM. Shortly thereafter, center descended us to FL290 and returned us to our original routing. Center did not advise either us or other aircraft as to altitude or separation violation. All 3 crew on our aircraft agree we were cleared to and were level at FL310. I do not know what led to this event (ie, who made the mistake).
Original NASA ASRS Text
Title: POTENTIAL CONFLICT, A SYS ERROR, OCCURS WHEN 2 ACR ACFT ARE ASSIGNED THE SAME WBOUND ALT OF FL310, ONE ACFT EBOUND, THE OTHER SWBOUND.
Narrative: ENRTE FROM CMH TO ATL ON HDG OF 190 DEGS MAGNETIC UNTIL READING ODF, THEN DIRECT, LEVEL AT FL310 ASSIGNED ALT, ZID GAVE US A R TURN TO HDG 270 DEGS MAGNETIC. AS WE WERE IN THE TURN, TCASII ADVISED 'TFC, TFC' AND I OBSERVED TARGET AT 9 O'CLOCK, 5 MI, OUR ALT. CTR ASKED OUR ASSIGNED ALT. I REPLIED FL310. CTR CALLED OTHER ACFT AND GAVE A TURN TO 180 DEGS MAGNETIC. ACFT SEPARATION APPEARED TO MAINTAIN AT 5 NM. SHORTLY THEREAFTER, CTR DSNDED US TO FL290 AND RETURNED US TO OUR ORIGINAL ROUTING. CTR DID NOT ADVISE EITHER US OR OTHER ACFT AS TO ALT OR SEPARATION VIOLATION. ALL 3 CREW ON OUR ACFT AGREE WE WERE CLRED TO AND WERE LEVEL AT FL310. I DO NOT KNOW WHAT LED TO THIS EVENT (IE, WHO MADE THE MISTAKE).
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.