Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 235; Flight Crew Type 10000
Situational Awareness; Distraction; Time Pressure
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Flight Crew Returned To Gate
Human Factors; Aircraft; Weather
It was a cold 20 degree C early morning. Upon arrival at the aircraft; I took a quick glance at the aircraft surfaces and didn't notice any frost. After my First Officer completed his walk around; I asked if he saw any frost and he said 'No'. During cockpit preparations we were distracted by items like the Flight Attendants requesting more ice; then later they asked for a new credit card battery replacement; then the ground power failed; and finally we noticed the Mode Control Panel (MCP) had no power. Maintenance took about 30 minutes; delaying the flight past scheduled departure. We taxied out and after notifying the flight attendants that we were ready for takeoff; the flight attendants informed us a company commuting Pilot told them there was frost on the wings. We returned to the ramp for deice. I believe the one hour time that elapsed from the preflight walk around to the takeoff; frost must have formed; and my First Officer and I failed to double-check before takeoff. We almost performed a takeoff with frost on the wings; but with help from our commuting Pilot; we averted the dangerous event.
I suppose there was enough time for some frost to form. The conditions were conducive to frost as well; i.e. calm winds. When the report was made to us that frost was on the wings; we again looked at the representative surfaces and could not see frost. But; obviously the Pilot wouldn't have gone through the trouble to report it to us if he didn't see frost.
Although their B737 was free of contamination during preflight by the time the flight crew taxied out; following servicing and maintenance delays; they were advised by a deadheading pilot via a Flight Attendant that there was frost on the wings. They returned for de-icing.