[Federal Register Volume 63, Number 181 (Friday, September 18, 1998)]
[Rules and Regulations]
[Pages 49819-49821]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-25003]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-62-AD; Amendment 39-10773; AD 98-05-14 R1]
RIN 2120-AA64


Airworthiness Directives; Cessna Aircraft Company Models T210N, 
P210N, and P210R Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; correction.

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SUMMARY: This amendment clarifies information contained in 
Airworthiness Directive (AD) 98-05-14, which currently requires 
revising the FAA-approved Airplane Flight Manual (AFM) to specify 
procedures that would prohibit flight in severe icing conditions (as 
determined by certain visual cues), limit or prohibit the use of 
various flight control devices while in severe icing conditions, and 
provide the flight crew with recognition cues for, and procedures for 
exiting from, severe icing conditions on certain Cessna Aircraft 
Company (Cessna) Models T210N, P210N, and P210R airplanes. That 
publication incorrectly references the possibility of certain ice 
accumulation on the ``lower'' surface of the wing, instead of the 
``upper'' surface of the wing while operating with the flaps extended. 
This incorrect statement may result in pilot misinterpretation of the 
icing effects with the flaps extended, and lead to an incorrect action. 
This document replaces the word ``lower'' with ``upper'' in this 
sentence. The actions specified in this AD are intended to continue to 
minimize the

[[Page 49820]]

potential hazards associated with operating these airplanes in severe 
icing conditions by providing more clearly defined procedures and 
limitations associated with such conditions.

EFFECTIVE DATE: September 22, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 97-CE-62-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

FOR FURTHER INFORMATION CONTACT: Mr. John P. Dow, Sr., Aerospace 
Engineer, FAA, Small Airplane Directorate, 1201 Walnut, suite 900, 
Kansas City, Missouri 64106; telephone: (816) 426-6932, facsimile: 
(816) 426-2169.

SUPPLEMENTARY INFORMATION:

Discussion

    On February 24, 1998, the FAA issued AD 98-05-14, Amendment 39-
10375 (63 FR 10519, March 4, 1998), which applies to Cessna Models 
T210N, P210N, and P210R airplanes. AD 98-05-14 was the result of a 
review of the requirements for certification of these airplanes in 
icing conditions, new information on the icing environment, and icing 
data provided currently to the flight crew.
    AD 98-05-14 requires revising the Limitations Section of the FAA-
approved Airplane Flight Manual (AFM) to specify procedures that would:
     Require flight crews to immediately request priority 
handling from Air Traffic Control to exit severe icing conditions (as 
determined by certain visual cues);
     Prohibit flight in severe icing conditions (as determined 
by certain visual cues);
     Prohibit use of the autopilot when ice is formed aft of 
the protected surfaces of the wing, or when an unusual lateral trim 
condition exists; and
     Require that all icing wing inspection lights be operative 
prior to flight into known or forecast icing conditions at night.
    That action also requires revising the Normal Procedures Section of 
the FAA-approved AFM to specify procedures that would:
     Limit the use of the flaps and prohibit the use of the 
autopilot when ice is observed forming aft of the protected surfaces of 
the wing, or if unusual lateral trim requirements or autopilot trim 
warnings are encountered; and
     Provide the flight crew with recognition cues for, and 
procedures for exiting from, severe icing conditions.

Need for the Correction

    The AD incorrectly states in paragraph (a)(2) of AD 98-05-14 that:

    Operation with flaps extended can result in a reduced wing 
angle-of-attack, with the possibility of ice forming on the lower 
surface further aft on the wing than normal, possibly aft of the 
protected area.

    The word ``lower'' in this sentence should be ``upper.''
    This incorrect statement may result in pilot misinterpretation of 
the icing effects with the flaps extended and lead to an incorrect 
action. The pilot of the affected airplanes can only see the lower wing 
surface. However, ice accretion on the upper surface of the wing, which 
the pilot cannot observe, is usually accompanied by ice accretion on 
the lower surface. As stated earlier, the pilot can observe ice 
accretion on the lower surface.
    Extension of flaps that results in a reduced angle-of-attack can 
change the relationship of the extent of ice on the upper and lower 
surfaces of the wing. For example, ice will tend to accrete more on the 
upper surface than on the lower surface at a reduced angle-of-attack. 
However, when flaps are extended in certain icing conditions, the 
reduction of ice further aft on the lower surface of the wing may lead 
the pilot to conclude incorrectly that there is a reduction of ice 
further aft on the upper surface. This is not correct; as stated 
earlier, the tendency is for more ice accretion on the upper surface. 
Usually, ice on the upper surface of the wing is more adverse to the 
aerodynamic characteristics of the airplane than is ice on the lower 
surface of the wing.
    Consequently, the FAA saw a need to clarify AD 98-05-14 to assure 
that this visual cue can be followed and that the appropriate cause and 
effect relationship is described.

Correction of Publication

    This document clarifies the intent of the previously discussed 
visual cue in paragraph (a)(2) of AD 98-05-14. This document also adds 
the amendment to section 39.13 of the Federal Aviation Regulations (14 
CFR 39.13).
    Since this action only clarifies the description of a visual cue in 
AD 98-05-14, it has no adverse economic impact and imposes no 
additional burden on any person than would have been necessary by the 
existing AD. Therefore, the FAA has determined that prior notice and 
opportunity for public comment are unnecessary.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Airworthiness Directive 
(AD) 98-05-14, Amendment 39-10375 (63 FR 10519, March 4, 1998), and by 
adding a new AD to read as follows:

98-05-14  R1 Cessna Aircraft Company: Amendment 39-10773; Docket No. 
97-CE-62-AD; Revises AD 98-05-14, Amendment 39-10375.

    Applicability: Models T210N (serial numbers 21063641 through 
21064897), P210N (serial numbers P21000386 through P21000834), and 
P210R (all serial numbers) airplanes; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (d) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated in the body of this AD, unless 
already accomplished.
    To minimize the potential hazards associated with operating the 
airplane in severe icing conditions by providing more clearly 
defined procedures and limitations associated with such conditions, 
accomplish the following:
    (a) Within 30 days after April 30, 1998 (the effective date AD 
98-05-14), accomplish the requirements of paragraphs (a)(1) and 
(a)(2) of this AD.

    Note 2: Operators should initiate action to notify and ensure 
that flight crewmembers are apprised of this change.

    (1) Revise the FAA-approved Airplane Flight Manual (AFM) by 
incorporating the following into the Limitations Section of the AFM. 
This may be accomplished by inserting a copy of this AD in the AFM.

``WARNING

    Severe icing may result from environmental conditions outside of 
those for which the airplane is certificated. Flight in

[[Page 49821]]

freezing rain, freezing drizzle, or mixed icing conditions 
(supercooled liquid water and ice crystals) may result in ice build-
up on protected surfaces exceeding the capability of the ice 
protection system, or may result in ice forming aft of the protected 
surfaces. This ice may not be shed using the ice protection systems, 
and may seriously degrade the performance and controllability of the 
airplane.
     During flight, severe icing conditions that exceed 
those for which the airplane is certificated shall be determined by 
the following visual cues. If one or more of these visual cues 
exists, immediately request priority handling from Air Traffic 
Control to facilitate a route or an altitude change to exit the 
icing conditions.

--Unusually extensive ice accumulation on the airframe and 
windshield in areas not normally observed to collect ice.
--Accumulation of ice on the lower surface of the wing aft of the 
protected area.

     Since the autopilot, when installed and operating, may 
mask tactile cues that indicate adverse changes in handling 
characteristics, use of the autopilot is prohibited when any of the 
visual cues specified above exist, or when unusual lateral trim 
requirements or autopilot trim warnings are encountered while the 
airplane is in icing conditions.
     All wing icing inspection lights must be operative 
prior to flight into known or forecast icing conditions at night. 
[NOTE: This supersedes any relief provided by the Master Minimum 
Equipment List (MMEL).]''

    (2) Revise the FAA-approved AFM by incorporating the following 
into the Normal Procedures Section of the AFM. This may be 
accomplished by inserting a copy of this AD in the AFM.

``THE FOLLOWING WEATHER CONDITIONS MAY BE CONDUCIVE TO SEVERE IN-FLIGHT 
ICING:

     Visible rain at temperatures below 0 degrees Celsius 
ambient air temperature.
     Droplets that splash or splatter on impact at 
temperatures below 0 degrees Celsius ambient air temperature.

Procedures for Exiting the Severe Icing Environment:

    These procedures are applicable to all flight phases from 
takeoff to landing. Monitor the ambient air temperature. While 
severe icing may form at temperatures as cold as -18 degrees 
Celsius, increased vigilance is warranted at temperatures around 
freezing with visible moisture present. If the visual cues specified 
in the Limitations Section of the AFM for identifying severe icing 
conditions are observed, accomplish the following:
     Immediately request priority handling from Air Traffic 
Control to facilitate a route or an altitude change to exit the 
severe icing conditions in order to avoid extended exposure to 
flight conditions more severe than those for which the airplane has 
been certificated.
     Avoid abrupt and excessive maneuvering that may 
exacerbate control difficulties.
     Do not engage the autopilot.
     If the autopilot is engaged, hold the control wheel 
firmly and disengage the autopilot.
     If an unusual roll response or uncommanded roll control 
movement is observed, reduce the angle-of-attack.
     Do not extend flaps when holding in icing conditions. 
Operation with flaps extended can result in a reduced wing angle-of-
attack, with the possibility of ice forming on the upper surface 
further aft on the wing than normal, possibly aft of the protected 
area.
     If the flaps are extended, do not retract them until 
the airframe is clear of ice.
     Report these weather conditions to Air Traffic 
Control.''
    (b) Incorporating the AFM revisions, as required by this AD, may 
be performed by the owner/operator holding at least a private pilot 
certificate as authorized by section 43.7 of the Federal Aviation 
Regulations (14 CFR 43.7), and must be entered into the aircraft 
records showing compliance with this AD in accordance with section 
43.9 of the Federal Aviation Regulations (14 CFR 43.9).
    (c) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.
    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, FAA, 1201 
Walnut, suite 900, Kansas City, Missouri 64106. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Small Airplane 
Directorate.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (e) All persons affected by this directive may examine 
information related to this AD at the FAA, Central Region, Office of 
the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, 
Missouri 64106.
    (f) This amendment revises AD 98-05-14, Amendment 39-10375.
    (g) This amendment becomes effective on September 22, 1998.

    Issued in Kansas City, Missouri, on September 11, 1998.
Michael K. Dahl,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-25003 Filed 9-17-98; 8:45 am]
BILLING CODE 4910-13-P