Aircraft returns to deicing pad after deadheading pilot, a passenger, reports ice on top of wing.

Attributes
ACN	206452
Time
Date	199203
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : den
State Reference	CO
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	ground : holding ground : preflight ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 230 flight time total : 6500 flight time type : 2800
ASRS Report	206452
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 14000 flight time type : 3000
ASRS Report	206221
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

I was the so on a widebody transport from den to iah. The WX in den was 36 degrees F with very light precipitation and 1600 ft ceiling. After arrival from lax and on preflight walkaround outside the aircraft and also viewing the wings and horizontal stabilizer from inside the aircraft, I found no ice, snow, or frost on wings, flight controls, leading edge devices, horizontal stabilizer or any other part of the aircraft as the temperature was above freezing. After a 45 min turnaround from gate and taxi to runway 35L and taking the runway for departure, call from a flight attendant in the rear of the aircraft stated a deadheading pilot saw frost forming on top of the wing. The captain then taxied the aircraft clear of runway 35L to the deice pad where the wings were deiced. I went back to the cabin to view the wings and returned to the cockpit to report to the captain that there was no frost visible. The captain then taxied the aircraft back to runway 35L and we departed for houston. Supplemental information from acn 206221: there was some frost observed on the wing, which happened after refueling, which could easily be mistaken for ice, which I think happened. In my judgement, the airplane and control surfaces were clear of any ice and safe to fly, but because an inexperienced pilot made the comment about needing deicing in the company of passenger, I decided the prudent thing to do was to deice.

Original NASA ASRS Text

Title: ACFT RETURNS TO DEICING PAD AFTER DEADHEADING PLT, A PAX, RPTS ICE ON TOP OF WING.

Narrative: I WAS THE SO ON A WDB FROM DEN TO IAH. THE WX IN DEN WAS 36 DEGS F WITH VERY LIGHT PRECIPITATION AND 1600 FT CEILING. AFTER ARR FROM LAX AND ON PREFLT WALKAROUND OUTSIDE THE ACFT AND ALSO VIEWING THE WINGS AND HORIZ STABILIZER FROM INSIDE THE ACFT, I FOUND NO ICE, SNOW, OR FROST ON WINGS, FLT CTLS, LEADING EDGE DEVICES, HORIZ STABILIZER OR ANY OTHER PART OF THE ACFT AS THE TEMP WAS ABOVE FREEZING. AFTER A 45 MIN TURNAROUND FROM GATE AND TAXI TO RWY 35L AND TAKING THE RWY FOR DEP, CALL FROM A FLT ATTENDANT IN THE REAR OF THE ACFT STATED A DEADHEADING PLT SAW FROST FORMING ON TOP OF THE WING. THE CAPT THEN TAXIED THE ACFT CLR OF RWY 35L TO THE DEICE PAD WHERE THE WINGS WERE DEICED. I WENT BACK TO THE CABIN TO VIEW THE WINGS AND RETURNED TO THE COCKPIT TO RPT TO THE CAPT THAT THERE WAS NO FROST VISIBLE. THE CAPT THEN TAXIED THE ACFT BACK TO RWY 35L AND WE DEPARTED FOR HOUSTON. SUPPLEMENTAL INFO FROM ACN 206221: THERE WAS SOME FROST OBSERVED ON THE WING, WHICH HAPPENED AFTER REFUELING, WHICH COULD EASILY BE MISTAKEN FOR ICE, WHICH I THINK HAPPENED. IN MY JUDGEMENT, THE AIRPLANE AND CTL SURFACES WERE CLR OF ANY ICE AND SAFE TO FLY, BUT BECAUSE AN INEXPERIENCED PLT MADE THE COMMENT ABOUT NEEDING DEICING IN THE COMPANY OF PAX, I DECIDED THE PRUDENT THING TO DO WAS TO DEICE.

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.