**\[4910-13\]**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Parts 91, 125, and 135**

**\[Docket No. FAA-2007-29281; Notice No. 08-06\]**

**RIN 2120-AJ09**

**Removal of Regulations Allowing for Polished Frost on Wings of
Airplanes**

**AGENCY:** Federal Aviation Administration (FAA), DOT.

**ACTION:** Notice of proposed rulemaking (NPRM).

**SUMMARY:** The FAA is proposing to remove provisions in its
regulations that allow for operations with "polished frost" (i.e., frost
polished to make it smooth) on the wings of airplanes operated under
parts 125, 135, and certain airplanes operated under part 91. The rule
would increase safety by not allowing operations with polished frost,
which the FAA has determined increases the risk of unsafe flight.

**DATES:** Send your comments on or before \[[INSERT DATE 90 DAYS AFTER
DATE OF PUBLICATION IN THE FEDERAL REGISTER]{.underline}\].

**ADDRESSES:** You may send comments identified by docket number
FAA-2007-29281 using any of the following methods:

-   [Federal eRulemaking Portal]{.underline}: Go to
    [http://www.regulations.gov](http://www.regulations.gov/) and follow
    the online instructions for sending your comments electronically.

-   [Mail]{.underline}: Send comments to Docket Operations, M-30; U.S.
    Department of Transportation, 1200 New Jersey Avenue, SE, Room
    W12-140, West Building Ground Floor, Washington, DC 20590-0001.

-   [Hand Delivery or Courier]{.underline}: Bring comments to Docket
    Operations in Room W12-140 of the West Building Ground Floor at 1200
    New Jersey Avenue, SE, Washington, DC, between 9 a.m. and 5 p.m.,
    Monday through Friday, except Federal holidays.

-   [Fax]{.underline}: Fax comments to Docket Operations at
    202-493-2251.

For more information on the rulemaking process, see the SUPPLEMENTARY
INFORMATION section of this document.

*Privacy:* We will post all comments we receive, without change, to
[http://www.regulations.gov](http://dms.dot.gov/), including any
personal information you provide. Using the search function of our
docket web site, anyone can find and read the electronic form of all
comments received into any of our dockets, including the name of the
individual sending the comment (or signing the comment for an
association, business, labor union, etc.). You may review DOT\'s
complete Privacy Act Statement in the [Federal Register]{.underline}
published on April 11, 2000 (65 FR 19477-78) or you may visit
[http://DocketsInfo.dot.gov](http://dms.dot.gov/).

*Docket*: To read background documents or comments received, go to
[http://www.regulations.gov](http://dms.dot.gov/) at any time and follow
the online instructions for accessing the docket. Or, go to the Docket
Operations in Room W12-140 of the West Building Ground Floor at 1200 New
Jersey Avenue, SE, Washington, DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.

**FOR FURTHER INFORMATION CONTACT:** For technical questions concerning
this proposed rule contact Mike Frank, AFS-260, Federal Aviation
Administration, 800 Independence Avenue S.W., Washington, DC 20591;
telephone (202) 267-8166 ; facsimile (202) 267-5299, e-mail
mike.frank@faa.gov.

For legal questions concerning this proposed rule contact Bruce
Glendening, Operations Law Branch - AGC-220, Federal Aviation
Administration, 800 Independence Avenue S.W., Washington, DC 20591;
telephone (202) 267-3073; facsimile (202) 267-7971, e-mail
bruce.glendening@faa.gov.

**SUPPLEMENTARY INFORMATION:**

Later in this preamble under the Additional Information section, we
discuss how you can comment on this proposal and how we will handle your
comments. Included in this discussion is related information about the
docket, privacy, and handling of proprietary or confidential business
information. We also discuss how you can get a copy of this proposal and
related rulemaking documents.

### Authority for this Rulemaking  

The FAA's authority to issue rules on aviation safety is found in Title
49 of the United States Code. Subtitle I, Section 106 describes the
authority of the FAA Administrator, including the authority to issue,
rescind, and revise regulations. Subtitle VII, Aviation Programs,
describes in more detail the scope of the agency's authority. This
rulemaking is promulgated under the authority described in Subtitle VII,
Part A, Chapter 447---Safety Regulation. Under section 44701 (a)(5), the
FAA is charged with promoting safe flight of civil aircraft by, among
other things, prescribing regulations the FAA finds necessary for safety
in air commerce.

**I. Background**

Currently, 14 CFR 91.527 (a), 125.221 (a), and 135.227 (a) allow pilots
to take off with frost adhering to wings or stabilizing or control
surfaces if that frost has been polished to make it smooth. This frost
is referred to as "polished frost." This procedure first appeared in the
[Federal Register]{.underline} as Civil Air Regulation Draft Release No.
60-13, a proposed revision of part 47 of the Civil Air Regulations, on
August 6, 1960.

Since 1960, the FAA and others have accumulated an extensive amount of
data that would indicate that any amount of contaminants on wings or
critical surfaces could be detrimental to the flight characteristics of
an aircraft. In Advisory Circular (AC) 135-17, the FAA recommends that
all wing frost be removed prior to takeoff, and states that if an
operator desires to polish the frost, the aircraft manufacturer's
recommended procedures should be followed
(<http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/MainFrame?OpenFrameSet>).
No current aircraft manufacturer, however, has issued any recommended
procedures for (1) polishing frost, or (2) conducting operations with
polished frost. In addition, the FAA has no data to support practical
guidance on determining how to polish frost on a surface to make it
acceptably smooth, other than completely removing the frost and
returning the airplane's critical lifting surfaces to uncontaminated
smoothness. Moreover, the term "polished frost" is ambiguous since no
standard of acceptable smoothness is provided. Also, means to ensure
that the "polished frost" surface smoothness is equivalent to that of
the uncontaminated airplane surface is operationally impractical.
Subsequently, the FAA issued two Safety Alerts for Operators
(SAFOs)\--06002 and 06014\-- advising against the practice of polishing
frost
(http://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/).

In addition, there are at least 11 known accidents in which individuals
attempted to "smooth" or polish frost, but the aircraft failed to
generate enough lift and crashed shortly after takeoff.[^1] There have
been a number of other takeoff accidents and fatalities that have
occurred when flightcrews have consciously decided to take off without
removing frost from the wings of their aircraft. Following the January
4, 2002 accident at Birmingham, England, the United Kingdom Aircraft
Accident Investigation Board recommended in its Safety Recommendation
2003-54 that the FAA, and all Authorities who follow FAA practice,
delete all reference to 'Polished Frost' within their regulations and
ensure that the term is expunged from Operations Manuals. In addition,
the U.S. National Transportation Safety Board (NTSB) has issued numerous
safety alerts urging operators to ensure that critical surfaces are free
of all contamination prior to takeoff.

**II.** **General Discussion of the Proposals**

As previously mentioned, numerous FAA ACs and Safety Alerts have been
issued since 1960 clearly pointing out the hazards of attempting to take
off with any frost on aircraft wings or control surfaces, polished or
not. Adverse aerodynamic effects for lifting surfaces begin as soon as
frost begins to adhere to the surfaces. Determining either when
sufficient polishing achieves a smooth surface or the smoothness of the
contaminated surface without instrumentation is impracticable. The sheen
of polished frost and its tactile smoothness can be misleading. In
addition, the FAA believes achieving uniform smoothness on all lifting
and control surfaces or even symmetrical smoothness in an operational
environment is impossible to determine.

Technical literature well documents the adverse aerodynamic effects of
surface roughness, such as frost and other ice that adhere to aircraft
surfaces. The literature indicates that surface roughness formed by
frost and adhering ice can result in significant adverse aerodynamic
effects for lifting surfaces, such as wings and flight control surfaces.
For example, (1) a contaminated wing's maximum lift may be reduced by 30
percent or more; (2) the angle of attack for maximum lift may be reduced
by several degrees; (3) drag may be increased significantly; and (4) the
airplane's handling qualities and performance may change unexpectedly
from that of the uncontaminated aircraft. The severity of these adverse
aerodynamic effects varies significantly (1) with the magnitude (height
and density) and location of the surface roughness, and (2) with the
location of the roughness relative to the surface leading edge where
significant variations may occur in the local airspeed and surface air
loads. Therefore, the FAA has determined that complete removal of frost
from critical surfaces to achieve uncontaminated surface smoothness is
necessary to ensure acceptable airplane airworthiness. If all wing
surfaces, other than those under the wing in the area of the fuel
tank[^2], and control surfaces are not uniformly smooth upon takeoff,
the FAA believes an unsafe condition exists.

The FAA is proposing to amend §§91.527 (a)(3), 125.221 (a), and 135.227
(a) to remove language permitting pilots to takeoff with "polished
frost" adhering to the wings or stabilizing or control surfaces.

Within part 91 subpart F, the current text of §91.527 (a) states that no
pilot may take off an airplane that has\-- (1) frost, snow, or ice
adhering to any propeller, windshield, or powerplant installation or to
an airspeed, altimeter, rate of climb, or flight attitude instrument
system; (2) snow or ice adhering to the wings or stabilizing or control
surfaces; or (3) any frost adhering to the wings or stabilizing or
control surfaces, unless that frost has been polished to make it smooth.
The FAA would amend the paragraph to remove the words "unless that frost
has been polished to make it smooth."

Part 91 subpart F provides for the operation of large and
turbine-powered multiengine airplanes and all fractional ownership
program aircraft (regardless of category, class, weight, powerplant or
number of engines). Therefore, the revised provisions in subpart F in
this NPRM would affect the operation of all fractional ownership program
aircraft under subpart K, regardless of whether the aircraft is large or
small and regardless of whether the aircraft is single or multi-engine.

#####  Similarly, current §§125.221 (a) and 135.227 (a) provide that no pilot may take off an airplane that has frost, ice, or snow adhering to any propeller, windshield, wing, stabilizing or control surface, to a powerplant installation, or to an airspeed, altimeter, rate of climb, or flight attitude instrument system, except that takeoffs may be made with frost adhering to the wings, or stabilizing or control surfaces, if the frost has been polished to make it smooth. The FAA would amend those sections to delete the words "except... \[t\]akeoffs may be made with frost adhering to the wings, or stabilizing or control surfaces, if the frost has been polished to make it smooth." These rule changes may also result in changes to an operator's operations specifications (OpSpecs) as they relate to ground deicing operations.

In addition, the FAA is responding to a recommendation from the Part
125/135 Aviation Rulemaking Committee, established on April 8, 2003,
which provided recommendations to the FAA regarding the safety and
applicability of standards of parts 125, 135, and associated
regulations. In this proposed rule, the FAA is therefore taking the
opportunity to correct the structure of §§91.527 (b), 125.221 (c), and
135.227 (c). Currently, in each of those paragraphs the phrase beginning
with the words "unless the aircraft has..." appears to apply only to
paragraph (2); however, that clause applies to all of the provisions of
the paragraph. In 1995, the FAA issued a legal interpretation (included
in the docket for this rulemaking action) to clarify that this language
applies to both IFR flight into known or forecast light or moderate
icing conditions and VFR flight into known light or moderate icing
conditions. The FAA is therefore proposing to re-structure those
paragraphs accordingly.

**III. Paperwork Reduction Act**

The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires that
the FAA consider the impact of paperwork and other information
collection burdens imposed on the public. We have determined that there
is no new information collection requirement associated with this
proposed rule.

**IV. International Compatibility**

In keeping with U.S. obligations under the Convention on International
Civil Aviation, it is FAA policy to comply with International Civil
Aviation Organization (ICAO) Standards and Recommended Practices to the
maximum extent practicable. The FAA has determined that there are no
ICAO Standards and Recommended Practices that correspond to these
proposed regulations.

**V. Regulatory Evaluation, Regulatory Flexibility Determination,
International Trade Impact Assessment, and Unfunded Mandates
Assessment**

[V.1. Regulatory Evaluation]{.underline}

Changes to Federal regulations must undergo several economic analyses.
First, Executive Order 12866 directs that each Federal agency shall
propose or adopt a regulation only upon a reasoned determination that
the benefits of the intended regulation justify its costs. Second, the
Regulatory Flexibility Act of 1980 (Public Law 96-354) requires agencies
to analyze the economic impact of regulatory changes on small entities.
Third, the Trade Agreements Act (Public Law 96-39) prohibits agencies
from setting standards that create unnecessary obstacles to the foreign
commerce of the United States. In developing U.S. standards, this Trade
Act requires agencies to consider international standards and, where
appropriate, that they be the basis of U.S. standards. Fourth, the
Unfunded Mandates Reform Act of 1995 (Public Law 104-4) requires
agencies to prepare a written assessment of the costs, benefits, and
other effects of proposed or final rules that include a Federal mandate
likely to result in the expenditure by State, local, or tribal
governments, in the aggregate, or by the private sector, of \$100
million or more annually (adjusted for inflation with base year of
1995). This portion of the preamble summarizes the FAA's analysis of the
economic impacts of this proposed rule. We suggest readers seeking
greater detail read the full regulatory evaluation, a copy of which we
have placed in the docket for this rulemaking.

In conducting these analyses, FAA has determined that this proposed
rule: (1) has benefits that justify its costs, (2) is not an
economically "significant regulatory action" as defined in section 3(f)
of Executive Order 12866, (3) is not "significant" as defined in DOT\'s
Regulatory Policies and Procedures; (4) would not have a significant
economic impact on a substantial number of small entities; (5) would not
create unnecessary obstacles to the foreign commerce of the United
States; and (6) would not impose an unfunded mandate on state, local, or
tribal governments, or on the private sector by exceeding the threshold
identified above. These analyses are summarized below.

Operators and pilots would have at least four alternatives to choose
from to deal with frost that may have accumulated on the wings of their
aircraft. These include: using wing covers, waiting for the frost to
melt, storing the aircraft in a heated hangar, or deicing the wing
surface. The FAA believes that wing covers are the lowest-cost
alternative. Assuming operators impacted by this proposed rule choose to
use wing covers, they would incur total costs of roughly \$164,000
(\$130,000 discounted) over the ten year period from 2009 to 2018. Of
these, \$155,000 (\$123,000 discounted) would accrue to operators in
Alaska, and \$9,500 (\$7,500 discounted) would accrue to mainland U.S.
operators. Benefits total roughly \$460,000 (\$320,000 discounted).
About \$433,000 (\$301,000 discounted) in benefits would accrue in
Alaska, while the remaining \$27,000 (\$19,000 discounted) would accrue
in the mainland U.S. These benefits are attributed to averted accidents,
injuries, and aircraft damage. Since benefits exceed costs for both
Alaska and the mainland U.S., the FAA concludes the proposed rule is
cost beneficial. The FAA calls for comments on this determination and
requests that all comments be accompanied by clear and detailed
supporting economic documentation.

[V. 2. Regulatory Flexibility Determination]{.underline}

The Regulatory Flexibility Act of 1980 (Public Law 96-354) (RFA)
establishes "as a principle of regulatory issuance that agencies shall
endeavor, consistent with the objectives of the rule and of applicable
statutes, to fit regulatory and informational requirements to the scale
of the businesses, organizations, and governmental jurisdictions subject
to regulation. To achieve this principle, agencies are required to
solicit and consider flexible regulatory proposals and to explain the
rationale for their actions to assure that such proposals are given
serious consideration." The RFA covers a wide-range of small entities,
including small businesses, not-for-profit organizations, and small
governmental jurisdictions.

Agencies must perform a review to determine whether a rule will have a
significant economic impact on a substantial number of small entities.
If the agency determines that it will, the agency must prepare a
regulatory flexibility analysis as described in the RFA.

However, if an agency determines that a rule is not expected to have a
significant economic impact on a substantial number of small entities,
section 605(b) of the RFA provides that the head of the agency may so
certify and a regulatory flexibility analysis is not required. The
certification must include a statement providing the factual basis for
this determination, and the reasoning should be clear.

This proposed rule would improve aviation safety by removing references
to the "polished frost" technique found in 14 CFR 91.527 (a), 125.221
(a), and 135.227 (a). At this time there is no part 91 operator that has
an authorized deicing program that incorporates the polished frost
procedure; therefore, this rulemaking only affects on-demand and
commuter services operating under parts 125 and 135. There are 57
operators operating 188 aircraft that would be affected by the rule.
Based on the SBA size standard defining a small unscheduled air carrier
as one having 1,500 employees or less per company, all of these
operators are considered small entities. As a result, the Regulatory
Flexibility Act applies.

The FAA assumes that most operators would choose to buy and use wing
covers to comply with the proposed rule. The other alternatives (waiting
for the frost to melt, storing the aircraft in a heated hangar, or
deicing the aircraft) are more expensive than using wing covers. The FAA
estimates that operators would choose to buy wing covers at an initial
cost of \$400, plus minimal additional fuel costs and, if needed, an
additional cost of \$400 after five years to replace a worn wing cover.

In Alaska, there are 21 operators with one aircraft apiece, and 30
operators operating the remaining 156 aircraft. In the mainland U.S.,
there are six operators operating 11 aircraft. The smallest operators
operate only one plane, and would incur a cost of approximately \$99 per
year as a result of this rulemaking, a cost that the FAA does not
consider significant. The operator that would be most impacted by the
rule operates 16 affected aircraft, and would incur costs of
approximately \$1,584 per year as a result of this rulemaking. This
operator has annual revenues of \$5 million. The cost of this rulemaking
represents 0.03 percent of the gross revenues of that operator, and the
FAA does not consider that amount significant. As a result, the FAA
certifies that this proposed rule would not have a significant economic
impact on a substantial number of small entities. The FAA requests
comments from affected entities on this finding and determination.

[V.3. International Trade Impact Assessment]{.underline}

The Trade Agreements Act of 1979 (Public Law 96-39) prohibits Federal
agencies from establishing any standards or engaging in related
activities that create unnecessary obstacles to the foreign commerce of
the United States. Legitimate domestic objectives, such as safety, are
not considered unnecessary obstacles. The statute also requires
consideration of international standards and, where appropriate, that
they be the basis for U.S. standards. The FAA has assessed the potential
effect of this proposed rule and has determined that it would have only
a domestic impact and would not affect international trade.

[V.4. Unfunded Mandates Assessment]{.underline}

Title II of the Unfunded Mandates Reform Act of 1995 (Public Law 104-4)
requires each Federal agency to prepare a written statement assessing
the effects of any Federal mandate in a proposed or final agency rule
that may result in an expenditure of \$100 million or more (adjusted
annually for inflation with the base year 1995) in any one year by
State, local, and tribal governments, in the aggregate, or by the
private sector; such a mandate is deemed to be a "significant regulatory
action." The FAA currently uses an inflation-adjusted value of \$136.1
million in lieu of \$100 million. This proposed rule does not contain
such a mandate.

**VI. Executive Order 13132, Federalism**

The FAA has analyzed this proposed rule under the principles and
criteria of Executive Order 13132, Federalism. We determined that this
action would not have a substantial direct effect on the States, on the
relationship between the national Government and the States, or on the
distribution of power and responsibilities among the various levels of
government, and, therefore, would not have federalism implications.

**VII. Regulations Affecting Intrastate Aviation in Alaska**

Section 40113(f) of 49 U.S.C. requires the Administrator, when modifying
regulations in title 14 of the CFR in a manner affecting intrastate
aviation in Alaska, to consider the extent to which Alaska is not served
by transportation modes other than aviation, and to establish
appropriate regulatory distinctions. Because the majority of potentially
affected operators are in Alaska, this proposed rule could, if adopted,
affect intrastate aviation in Alaska. The FAA believes, however, that
over 60% of aircraft currently operating in Alaska do not rely on this
procedure. For the remainder of affected operators, the cost of
compliance would be minimal. The FAA, therefore, specifically requests
comments on whether there is justification for applying the proposed
rule differently in intrastate operations in Alaska.

**VIII. Environmental Analysis**

FAA Order 1050.1E identifies FAA actions that are categorically excluded
from preparation of an environmental assessment or environmental impact
statement under the National Environmental Policy Act in the absence of
extraordinary circumstances. The FAA has determined this proposed
rulemaking action qualifies for the categorical exclusion identified in
paragraph 312 and involves no extraordinary circumstances.

**IX. Regulations that Significantly Affect Energy Supply, Distribution,
or Use**

The FAA has analyzed this NPRM under Executive Order 13211, Actions
Concerning Regulations that Significantly Affect Energy Supply,
Distribution, or Use (May 18, 2001). We have determined that it is not a
"significant energy action" under the executive order because it is not
a "significant regulatory action" under Executive Order 12866, and it is
not likely to have a significant adverse effect on the supply,
distribution, or use of energy.

**X. Additional Information**

[Comments Invited]{.underline}

The FAA invites interested persons to participate in this rulemaking by
submitting written comments, data, or views. We also invite comments
relating to the economic, environmental, energy, or federalism impacts
that might result from adopting the proposals in this document. The most
helpful comments reference a specific portion of the proposal, explain
the reason for any recommended change, and include supporting data. To
ensure the docket does not contain duplicate comments, please send only
one copy of written comments, or if you are filing comments
electronically, please submit your comments only one time.

We will file in the docket all comments we receive, as well as a report
summarizing each substantive public contact with FAA personnel
concerning this proposed rulemaking. Before acting on this proposal, we
will consider all comments we receive on or before the closing date for
comments. We will consider comments filed after the comment period has
closed if it is possible to do so without incurring expense or delay. We
may change this proposal in light of the comments we receive.

[Availability of Rulemaking Documents]{.underline}

You can get an electronic copy of rulemaking documents using the
Internet by---

1.  Searching the Federal eRulemaking Portal
    ([http://www.regulations.gov](http://dms.dot.gov/search));

```{=html}
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1.  Visiting the FAA's Regulations and Policies web page at
    http://www.faa.gov/regulations_policies/; or

2.  Accessing the Government Printing Office's web page at
    http://www.gpoaccess.gov/fr/index.html.

You can also get a copy by sending a request to the Federal Aviation
Administration, Office of Rulemaking, ARM-1, 800 Independence Avenue
S.W, Washington, DC  20591, or by calling (202) 267-9680. Be sure to
identify the docket number, notice number, or amendment number of this
rulemaking.

You may access all documents the FAA considered in developing this
proposed rule, including economic analyses and technical reports, from
the internet through the Federal eRulemaking Portal referenced in
paragraph (1).

**List of Subjects**

[14 CFR Part 91]{.underline}

Aircraft, Airmen, Airports, Aviation safety, Freight.

[14 CFR Part 125]{.underline}

Aircraft, Airmen, Aviation safety.

[14 CFR Part 135]{.underline}

Air taxis, Aircraft, Airmen, Aviation safety.

### The Proposed Amendment

In consideration of the foregoing, the Federal Aviation Administration
proposes to amend chapter I of title 14, Code of Federal Regulations, as
follows:

**PART 91\--GENERAL OPERATING AND FLIGHT RULES**

1\. The authority citation for part 91 continues to read as follows:

Authority: 49 U.S.C. 106(g), 1155, 40103, 40113, 40120, 44101, 44111,
44701, 44704, 44709, 44711, 44712, 44715, 44716, 44717, 44722, 46306,
46315, 46316, 46504, 46506--46507, 47122, 47508, 47528--47531, articles
12 and 29 of the Convention on International Civil Aviation (61 Stat.
1180).

2\. Amend §91.527 by revising paragraphs (a) and (b) to read as follows:

**§91.527 Operating in icing conditions.**

\(a\) No pilot may take off an airplane that has frost, ice, or snow
adhering to any propeller, windshield, stabilizing or control surface;
to a powerplant installation; or to an airspeed, altimeter, rate of
climb, or flight attitude instrument system or wing, except that
takeoffs may be made with frost under the wing in the area of the fuel
tanks if authorized by the FAA.

\(b\) No pilot may fly under IFR into known or forecast light or
moderate icing conditions, or under VFR into known light or moderate
icing conditions, unless---

\(1\) The aircraft has functioning deicing or anti-icing equipment
protecting each rotor blade, propeller, windshield, wing, stabilizing or
control surface, and each airspeed, altimeter, rate of climb, or flight
attitude instrument system; or

\(2\) The airplane has ice protection provisions that meet section 34 of
Special Federal Aviation Regulation No. 23; or

\(3\) The airplane meets transport category airplane type certification
provisions.

\* \* \* \* \*

##### PART 125---CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD CAPACITY OF 6,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT

3\. The authority citation for part 125 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701--44702, 44705, 44710--44711,
44713, 44716--44717, 44722.

4\. Amend §125.221 by revising paragraphs (a) and (c) to read as
follows:

**§125.221 Icing conditions: Operating limitations.**

\(a\) No pilot may take off an airplane that has frost, ice, or snow
adhering to any propeller, windshield, stabilizing or control surface;
to a powerplant installation; or to an airspeed, altimeter, rate of
climb, flight attitude instrument system, or wing, except that takeoffs
may be made with frost under the wing in the area of the fuel tanks if
authorized by the FAA.

\* \* \* \* \*

\(c\) No pilot may fly under IFR into known or forecast light or
moderate icing conditions, or under VFR into known light or moderate
icing conditions, unless---

\(1\) The aircraft has functioning deicing or anti-icing equipment
protecting each rotor blade, propeller, windshield, wing, stabilizing or
control surface, and each airspeed, altimeter, rate of climb, or flight
attitude instrument system; or

\(2\) The airplane has ice protection provisions that meet appendix C of
this part; or

\(3\) The airplane meets transport category airplane type certification
provisions.

\* \* \* \* \*

**PART 135---OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS
AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT**

5\. The authority citation for part 135 continues to read as follows:

Authority: 49 U.S.C. 106(g), 41706, 40113, 44701--44702, 44705, 44709,
44711--44713, 44715--44717, 44722, 45101--45105.

6\. Amend §135.227 by revising paragraphs (a) and (c) to read as
follows:

**§135.227 Icing conditions: Operating limitations.**

\(a\) No pilot may take off an aircraft that has frost, ice, or snow
adhering to any rotor blade, propeller, windshield, stabilizing or
control surface; to a powerplant installation; or to an airspeed,
altimeter, rate of climb, flight attitude instrument system, or wing,
except that takeoffs may be made with frost under the wing in the area
of the fuel tanks if authorized by the FAA.

\* \* \* \* \*

\(c\) No pilot may fly under IFR into known or forecast light or
moderate icing conditions or under VFR into known light or moderate
icing conditions, unless---

\(1\) The aircraft has functioning deicing or anti-icing equipment
protecting each rotor blade, propeller, windshield, wing, stabilizing or
control surface, and each airspeed, altimeter, rate of climb, or flight
attitude instrument system; or

\(2\) The airplane has ice protection provisions that meet section 34 of
appendix A of this part; or

\(3\) The airplane meets transport category airplane type certification
provisions.

\* \* \* \* \*

[]{.mark}

Issued in Washington, DC, on May 2, 2008. .

John M. Allen

Acting Director,

Flight Standards Service

[^1]: Nine of the 11 accidents would not have been prevented by this
    proposed rule, since the aircraft were involved in non-part 91
    subpart F operations. Nevertheless, the FAA believes they illustrate
    the risk involved in flying with polished frost.

[^2]: Takeoffs may be made with frost under the wing area of the fuel
    tanks if authorized by the FAA. (See e.g., 14 CFR 125.221 (a)(2) and
    135.227 (a)(2).)