Investigators also focused on deicing practices at LaGuardia . They found that the airport was using only Type I deicing fluid , not Type II . Type I fluids are used for the actual deicing of the jet , while Type II fluids are used for preventing buildup of ice . At the time of the accident , LaGuardia had prohibited the use of Type II deicing fluid because tests suggested that if it fell onto runways it reduced friction . Investigators noted the change had been made because of LaGuardia 's shorter runways and the fact that if an aircraft left the vicinity of the runway , it would come to rest in the cold water surrounding Runway 13 . The accident report , however , criticised the fact that the majority of the airplane operators in the United States relied only upon Type I fluids for protection , and they do not use Type II . The board stated that tests have shown that both Type I and Type II fluids do flow off the wings of a treated airplane in significant amounts during the initial takeoff ground run . The NTSB stated : There are a number of views on the potential uses of Type I and II fluids . The use of Type I fluid raises concern because its holdover time is shorter than the holdover time for Type II fluid under certain conditions . Both fluids are under scrutiny for their environmental impacts , and it is uncertain if Type II fluid diminishes the runway coefficient of friction since the fluid rolls off the airplane during the takeoff roll . Also , the use of either type fluid may result in a temporary degradation in the airplane 's aerodynamic performance , a reduced stall margin , and an increase in drag . While it was not named as a cause of the accident , investigators also found that the passenger safety briefing cards in the airplane showed two types of galley service doors . However , only one door is installed on a particular F28 model at any one time . The examination also showed that the safety card did not show how to operate either of the two types of galley service doors in the emergency mode if the normal opening mode failed . However , the final report stated that this " did not contribute to the fatalities in the accident . " The final report , published by the NTSB , cited the probable cause of the accident to be : ... the failure of the airline industry and the Federal Aviation Administration to provide flight crews with procedures , requirements , and criteria compatible with departure delays in conditions conducive to airframe icing and the decision by the flight crew to take off without positive assurance that the airplane 's wings were free of ice accumulation after 35 minutes of exposure to precipitation following de-icing . The ice contamination on the wings resulted in an aerodynamic stall and loss of control after lift-off . Contributing to the cause of the accident were the inappropriate procedures used by , and inadequate coordination between , the flight crew that led to a takeoff rotation at a lower than prescribed air speed . The NTSB made several recommendations to the FAA , including requiring that " flight crew members and appropriate ground personnel responsible for the inspection of transport-category airplanes for wing contamination receive specific periodic training that will illustrate what contamination looks like and feels like on a wing and the amount of contamination that is detectable under different light conditions " . They also ordered " airlines to establish a way to inform fight crews of the type of deicing fluid and mixture used , the current moisture accumulation rate , and the available holdover time . " With regard to the obstructions that the airplane collided with during the accident sequence , the NTSB ordered the modification or replacement of " all pump houses adjacent to Runway 13/31 so that they are not obstructions to airplanes " . They also ordered a study on the " feasibility of building a frangible ILS antenna array for LaGuardia Airport " Further , they ordered a review of Fokker F28-4000 passenger safety briefing cards " to ensure that they clearly and accurately depict the operation of the two types of forward cabin doors in both their normal and emergency modes and that they describe clearly and accurately how to remove the overwing emergency exit and cover . " The crash was featured on National Geographic Channel in an episode of the television program '' Mayday '' ( '' Air Crash Investigation '' / '' Air Emergency '' ) entitled '' Cold Case '' , where the accident was compared with Air Ontario Flight 1363 , which crashed in Dryden , Ontario , after the crew did not deice their jet . The program opened by saying that Canadian investigators were " stunned " to hear of the USAir accident , as it mirrored the Air Ontario flight which had occurred three years earlier
Air Ontario Flight 1363
Air Ontario Flight 1363
USAir Flight 405