Knold, re your
so I assume the characteristics of the type IV fluid has been changed since this recommendation was issued, correct?
It is always a danger to assume anything in aviation. I do not know of any specific changes in the specification, but there could have been a tightening of the testing of fluids against the specification or additions to the specification to clarify the problems of dry out. However many problems remain such as the fluid characteristics when ‘contaminated’ with precipitation during hold over; I understand that the Canadian DoT has done some testing in this area. Similarly there could be problems if the fluid is over applied; a very thick layer may not shear off the tail / wing or fall into in the tailplane/ elevator / servo control tab gap, leading to aerodynamic degradation.
hawk37, I understand that the ATR series of aircraft have large performance restrictions when using any thickened fluid (type 2 or type 4); similarly the Saab 2000 has revised takeoff speeds and trim settings. And possibly the Dash 8 too. Some BAE turboprops have notes to crew re increased control forces.
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