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37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
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An air carrier B737 flight crew is concerned that they may have climbed to the wrong altitude. They may have confused FL270 with FL370 and later they overheard, in the backgnd of an ATC transmission, a discussion about an aircraft that should have leveled at FL270.
| Attributes | |
| ACN | 379950 |
| Time | |
| Date | 199709 |
| Day | Sat |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : gso |
| State Reference | NC |
| Altitude | msl bound lower : 27000 msl bound upper : 37000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zdc tower : phl |
| Operator | common carrier : air carrier |
| Make Model Name | B737-400 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other |
| Flight Phase | climbout : intermediate altitude |
| Flight Plan | IFR |
| Aircraft 2 | |
| Make Model Name | Any Unknown or Unlisted Aircraft Manufacturer |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 110 flight time total : 8000 flight time type : 2200 |
| ASRS Report | 379950 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | other anomaly other |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : detected after the fact |
| Consequence | Other |
| Miss Distance | horizontal : 42000 vertical : 0 |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | other |
Narrative:
On climb out we received frequency change from low sector to high sector out of FL220. We received clearance to FL370, our filed altitude. We selected FL370 in the altitude window and the captain and I both pointed to it, as is our company procedure. The captain read back FL370 to ATC. Out of FL270 I noticed a target on our TCASII at FL280 7 NM ahead. We continued our climb toward FL370. At approximately FL300 I heard controllers discussing someone who was 'cleared to FL270' and they 'didn't know where he was going,' in the backgnd as we were given a radio frequency change. Nothing was ever indicated to us that there may have been a problem. It was fairly early and there wasn't that much traffic at that time in our area. So later in the day, I began to become concerned that it may have been us the controllers were talking about, and we may not have been cleared to FL370 but to FL270. When issuing altitude clrncs ATC should use the ICAO phonetic three-seven-O to avoid confusion. Also we as pilots should read back clrncs the same way.
Original NASA ASRS Text
Title: AN ACR B737 FLC IS CONCERNED THAT THEY MAY HAVE CLBED TO THE WRONG ALT. THEY MAY HAVE CONFUSED FL270 WITH FL370 AND LATER THEY OVERHEARD, IN THE BACKGND OF AN ATC XMISSION, A DISCUSSION ABOUT AN ACFT THAT SHOULD HAVE LEVELED AT FL270.
Narrative: ON CLBOUT WE RECEIVED FREQ CHANGE FROM LOW SECTOR TO HIGH SECTOR OUT OF FL220. WE RECEIVED CLRNC TO FL370, OUR FILED ALT. WE SELECTED FL370 IN THE ALT WINDOW AND THE CAPT AND I BOTH POINTED TO IT, AS IS OUR COMPANY PROC. THE CAPT READ BACK FL370 TO ATC. OUT OF FL270 I NOTICED A TARGET ON OUR TCASII AT FL280 7 NM AHEAD. WE CONTINUED OUR CLB TOWARD FL370. AT APPROX FL300 I HEARD CTLRS DISCUSSING SOMEONE WHO WAS 'CLRED TO FL270' AND THEY 'DIDN'T KNOW WHERE HE WAS GOING,' IN THE BACKGND AS WE WERE GIVEN A RADIO FREQ CHANGE. NOTHING WAS EVER INDICATED TO US THAT THERE MAY HAVE BEEN A PROB. IT WAS FAIRLY EARLY AND THERE WASN'T THAT MUCH TFC AT THAT TIME IN OUR AREA. SO LATER IN THE DAY, I BEGAN TO BECOME CONCERNED THAT IT MAY HAVE BEEN US THE CTLRS WERE TALKING ABOUT, AND WE MAY NOT HAVE BEEN CLRED TO FL370 BUT TO FL270. WHEN ISSUING ALT CLRNCS ATC SHOULD USE THE ICAO PHONETIC THREE-SEVEN-O TO AVOID CONFUSION. ALSO WE AS PLTS SHOULD READ BACK CLRNCS THE SAME WAY.
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.