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B737-700 flight crew expressed concern they may not have complied with policy when they departed in snowy conditions without conducting a wing check from the cabin.
| Attributes | |
| ACN | 1239664 |
| Time | |
| Date | 201502 |
| Local Time Of Day | 0601-1200 |
| Place | |
| Locale Reference | ZZZ.Airport |
| State Reference | US |
| Environment | |
| Flight Conditions | IMC |
| Light | Dawn |
| Aircraft 1 | |
| Make Model Name | B737-700 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Taxi |
| Flight Plan | IFR |
| Person 1 | |
| Function | Captain |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Experience | Flight Crew Last 90 Days 179 Flight Crew Type 8600 |
| Person 2 | |
| Function | First Officer |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Experience | Flight Crew Last 90 Days 194 |
| Events | |
| Anomaly | Deviation - Procedural Published Material / Policy |
Narrative:
Upon pushback at ZZZ; ATIS a reported 3/4 mile visibility with light snow. This concurred with our snowfall intensity based upon visibility chart and our aircraft was deiced using 100% dow ucar ad-40 with a holdover time between 1+00 to 1+30 minutes. Upon completion of deicing; ATIS east reported 1/4 mile and heavy snow and an RVR of 2400 touchdown and 2600 rollout. The snowfall intensity based upon visibility chart does not have a holdover time for heavy snow in this case but it does contain an RVR component; which indicated that an RVR of 2400 equated to light snow.as we approached the end of runway 01; the tower reported RVR of 4000; but ATIS G reported 1/4 mile visibility and heavy snow. Since the RVR is a reported measurement and the tower visibility is subjective after discussion amongst ourselves we completed the cockpit inspection of the wings; finished our checklist; and departed without incident. I did not complete the cabin wing inspection required in the aom for heavy snow because I felt the reported RVR was a more accurate measurement of visibility and reflected what I was seeing out my window.recommendation: determine and delineate which of these two sources takes precedence when determining snowfall intensity based upon visibility for the calculation of holdover times and required cabin/cockpit wing inspection.
Original NASA ASRS Text
Title: B737-700 flight crew expressed concern they may not have complied with policy when they departed in snowy conditions without conducting a wing check from the cabin.
Narrative: Upon pushback at ZZZ; ATIS A reported 3/4 mile visibility with light snow. This concurred with our snowfall intensity based upon visibility chart and our aircraft was deiced using 100% DOW UCAR AD-40 with a holdover time between 1+00 to 1+30 minutes. Upon completion of deicing; ATIS E reported 1/4 mile and heavy snow and an RVR of 2400 touchdown and 2600 rollout. The snowfall intensity based upon visibility chart does not have a holdover time for heavy snow in this case but it does contain an RVR component; which indicated that an RVR of 2400 equated to light snow.As we approached the end of Runway 01; the Tower reported RVR of 4000; but ATIS G reported 1/4 mile visibility and heavy snow. Since the RVR is a reported measurement and the Tower visibility is subjective after discussion amongst ourselves we completed the cockpit inspection of the wings; finished our checklist; and departed without incident. I did not complete the cabin wing inspection required in the AOM for heavy snow because I felt the reported RVR was a more accurate MEASUREMENT of visibility and reflected what I was seeing out my window.Recommendation: Determine and delineate which of these two sources takes precedence when determining snowfall intensity based upon visibility for the calculation of holdover times and required cabin/cockpit wing inspection.
Data retrieved from NASA's ASRS site 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.