Narrative:

Crew members have reported there to be a common misconception involving the deice card and procedures even among check airmen. The threat is from type iv anti-icing fluid applied on an overnight contaminating the wing and therefore producing >10% loss of lift allowed by FAA testing. The checklist begins with the statement regarding deicing prior to flight crew arrival and advises the crew on what to do if no contamination is expected. This leads the crew to think of contamination in terms of environmental factors and ends with a red stop sign. Directly below that the checklist asks if deicing is required and directs the crew that if anti-icing type iv has been placed on the jet prior to flight crew arrival then the jet needs to be anti-iced with type I. The threat here is that apparently the checklist creates an environment where the hazard of type iv fluid used in a way it was not designed can be easily masked. All deicing fluid is designed to shear off the wing on or by rotation (it is tested at 100 KTS for jets) and produce no more than a 10% loss in lift and an acceptable stall margin. Type iv fluid that is allowed to obtain a concentration greater than its application strength fails this test and does not shear off per FAA testing criteria. Although the card does in fact state this if read through; one member was quoted by his chief pilot that deicing was not required and that he should pay more attention to proper checklist usage. He was counseled that doing anything after the red stop sign was an improper use of the checklist. Hey; I know; I'm just relaying the news. I recommend two action items. One; that training re-emphasizes this. Two; I would recommend coordination with the union human factors department and company to possibly re-order the sequence in the card.

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Original NASA ASRS Text

Title: An air carrier pilot notes a common misconception about Type IV anti-ice fluid application prior to a day's flight can contaminate the wing and must be removed with Type I fluid.

Narrative: Crew members have reported there to be a common misconception involving the deice card and procedures even among Check Airmen. The threat is from Type IV anti-icing fluid applied on an overnight contaminating the wing and therefore producing >10% loss of lift allowed by FAA testing. The checklist begins with the statement regarding deicing prior to flight crew arrival and advises the crew on what to do if no contamination is expected. This leads the crew to think of contamination in terms of environmental factors and ends with a red stop sign. Directly below that the checklist asks if deicing is required and directs the crew that if ANTI-ICING Type IV has been placed on the jet prior to flight crew arrival then the jet needs to be anti-iced with Type I. The threat here is that apparently the checklist creates an environment where the hazard of Type IV fluid used in a way it was not designed can be easily masked. All deicing fluid is designed to shear off the wing on or by rotation (it is tested at 100 KTS for jets) and produce no more than a 10% loss in lift and an acceptable stall margin. Type IV fluid that is allowed to obtain a concentration greater than its application strength fails this test and does not shear off per FAA testing criteria. Although the card does in fact state this if read through; one member was quoted by his Chief Pilot that deicing was not required and that he should pay more attention to proper checklist usage. He was counseled that doing anything after the red stop sign was an improper use of the checklist. Hey; I know; I'm just relaying the news. I recommend two action items. One; that training re-emphasizes this. Two; I would recommend coordination with the Union Human Factors Department and Company to possibly re-order the sequence in the card.

Data retrieved from NASA's ASRS site as of April 2012 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.