Narrative:

We arrived at the airplane at the gate in stl at XA10. The WX was clear and sunny with temperature of -7 degrees C. On taxi out, flight attendants rang saying a passenger observed frost on top of the wings. I had observed no moisture or contamination on the aircraft during my preflight. The captain sent me back for an inspection from within the cabin. With the sunshine on the wing there appeared to be a few patches of thin hoar frost which was not visible from my ground walkaround. We taxied back to the gate and were deiced. After being deiced, the captain sent me back for another inspection. The wings were clear, I thanked the passenger who had pointed it out, and we continued our flight.

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Original NASA ASRS Text

Title: A PAX NOTES HOAR FROST ON THE WING DURING TAXI, NOTIFIES CREW WHO INVESTIGATES AND RETURNS TO THE GATE FOR DEICING.

Narrative: WE ARRIVED AT THE AIRPLANE AT THE GATE IN STL AT XA10. THE WX WAS CLR AND SUNNY WITH TEMP OF -7 DEGS C. ON TAXI OUT, FLT ATTENDANTS RANG SAYING A PAX OBSERVED FROST ON TOP OF THE WINGS. I HAD OBSERVED NO MOISTURE OR CONTAMINATION ON THE ACFT DURING MY PREFLT. THE CAPT SENT ME BACK FOR AN INSPECTION FROM WITHIN THE CABIN. WITH THE SUNSHINE ON THE WING THERE APPEARED TO BE A FEW PATCHES OF THIN HOAR FROST WHICH WAS NOT VISIBLE FROM MY GND WALKAROUND. WE TAXIED BACK TO THE GATE AND WERE DEICED. AFTER BEING DEICED, THE CAPT SENT ME BACK FOR ANOTHER INSPECTION. THE WINGS WERE CLR, I THANKED THE PAX WHO HAD POINTED IT OUT, AND WE CONTINUED OUR FLT.

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.