Do any other countries take as long as the US to transfer government power following an election? To learn more, see our tips on writing great answers. Each engine, with all icing protection systems operating, must: (a) Operate throughout its flight power range, including the minimum descent idle rotor speeds achievable in flight, in the icing conditions defined for turbojet, turbofan, and turboprop engines in Appendices C and O of part 25 of this chapter, and Appendix D of this part, and for turboshaft engines in Appendix C of part 29 of this chapter, without the accumulation of ice on the engine components that: (1) Adversely affects engine operation or that causes an unacceptable permanent loss of power or thrust or unacceptable increase in engine operating temperature; or, (2) Results in unacceptable temporary power loss or engine damage; or. Other answers have explained how the ice forms. Before the flight, the copilot called Oakland Flight Service to file an IFR flight plan and request a standard weather briefing. The pilot in command was in the left seat and the copilot, who was working the radios, was in the right seat. Certain atmospheric conditions make ice more likely to form. What did Lego set *instruction manuals* look like in the past? A cool, moist air mass is a perfect recipe for induction ice to form, even if there is no visible moisture present. The FAA has issued an AD (Airworthiness Directive) recently about this, incidents with the newer GEnx engines on 747-8 and 787 aircraft, Hot Meta Posts: Allow for removal by moderators, and thoughts about future…, Goodbye, Prettify. After the accident, the PIC reported that he had noticed a reduction in manifold pressure and airspeed. Use MathJax to format equations. different aircraft and occurs under a wide range of meteorological The general meteorological conditions in the vicinity of the accident site included cloud bases at 2,750 feet msl, extending up to 9,000 feet, with relative humidity at 75 percent. At 6:26 p.m., the Seminole declared an emergency and requested vectors to an airport immediately because of "engine problems relating to induction ice." When ice buildup blocks airflow to the engine, it can lead to a reduction of engine power or even complete engine failure. Nothing at all against Jon Story's nicely technical answer, but I think this one is a far better option with the references to ADs indicating potential issues due to icing in engines. The Seminole was not certified for flight in known icing conditions and, aside from carburetor and pitot heat, had no anti/deice systems. (b) Operate throughout its flight power range, including minimum descent idle rotor speeds achievable in flight, in the icing conditions defined for turbojet, turbofan, and turboprop engines in Appendices C and O of part 25 of this chapter, and for turboshaft engines in Appendix C of part 29 of this chapter. If the ice melts but then freezes again on metal surfaces, accumulating ice can either break into chunks that damage turbine blades, or melt and douse the ignition system. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.