Monday, November 30, 2009

New FAA rule prohibits takeoffs with 'polished frost'

by B.N. Sullivan

FAA logoThe U.S. Federal Aviation Administration (FAA) has issued a new rule that prohibits takeoffs with “polished frost” — frost buffed to make it smooth — on the wings, stabilizers and control surfaces of several classes of aircraft. The new rule applies to aircraft operated under 14 CFR Part 91 subpart F, and Parts 125 and 135, and makes those operations consistent with Part 121 with respect to its prohibition on operations with polished frost.

The FAA summarizes the new Final Rule this way:
This final rule removes language from part 91 subpart F, and parts 125 and 135, which permits aircraft to takeoff with frost that has been polished to make it smooth (“polished frost”) on critical surfaces. Under the final rule, operators will be required to remove any frost adhering to critical surfaces prior to takeoff.
Additionally, the rule restructures language in parts 91, 125, and 135 to clarify that aircraft must have functioning deicing or anti-icing equipment to fly under IFR into known or forecast light or moderate icing conditions, or under VFR into known light or moderate icing conditions.
The new rules become effective on January 30, 2010. According to the FAA, there are 57 operators flying 188 aircraft affected by the rule changes.

Today the FAA issued a press release in conjunction with announcement of the new rule, which said, in part:
Frost can affect the aerodynamics of wings and control surfaces, and the safest action is to completely remove it. Previous FAA guidance recommended removing all wing frost prior to takeoff, but allowed it to be polished smooth if the aircraft manufacturer’s recommended procedures were followed. But manufacturers never published standards of acceptable smoothness for polished frost, and the FAA has no data to determine exactly how to polish frost to satisfactory smoothness.
“The FAA has advised pilots not to take off with frost or ice contaminating their wings for years because it made good sense,” said FAA Administrator Randy Babbitt. “Now, it’s the law.”

Here is the link to the full text of the new rule: Removal of Regulations Allowing for Polished Frost - 27-page 'PDF' file

UPDATE Dec. 3, 2009: A reader alerted me to the fact that the link to the new rule, displayed above, no longer works. Here is the link the FAA Press release about the new rule banning takeoffs with polished frost; the press release contains a brief summary of the rule. The link at the bottom of that press release is the same as the one I have posted above, and it does appear to be broken at this time. I'm hoping that is a temporary situation.

Meanwhile, here is a link to an alternate source for the new FAA rule. The text of the rule begins about halfway down the left hand column of this 7-page 'pdf' document.