Federal Register / Vol. 61, No. 89 / Tuesday, May 7, 1996 / Rules and Regulations 20669

Note 2: Operators must 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

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 accreted on the

airframe in areas not normally observed to

collect ice

—Accumulation of ice on the upper surface

of the wing aft of the protected area

• Since the autopilot 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 icing detection lights must be

operative prior to flight into 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

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 during extended

operation 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) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager,

Standardization Branch, ANM–113, FAA,

Transport Airplane Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Operations

Inspector, who may add comments and then

send it to the Manager, Standardization

Branch, ANM–113.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Standardization Branch,

ANM–113.

(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) This amendment becomes effective on

June 11, 1996.

Issued in Renton, Washington, on April 24,

1996.

Ronald T. Wojnar,

Manager, Transport Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 96–10775 Filed 5–1–96; 3:26 pm]

BILLING CODE 4910–13–P

14 CFR Part 39

[Docket No. 96–NM–14–AD; Amendment

39–9595; AD 96–09–19]

RIN 2120–AA64

Airworthiness Directives; Jetstream

Model 4101 Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to all Jetstream Model 4101

airplanes, that requires revising the

Airplane Flight Manual (AFM) to

provide the flight crew with recognition

cues for, and procedures for exiting

from, severe icing conditions, and to

limit or prohibit the use of various flight

control devices. This amendment is

prompted by results of a review of the

requirements for certification of the

airplane in icing conditions, new

information on the icing environment,

and icing data provided currently to the

flight crews. The actions specified by

this AD are intended to prevent or

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.

EFFECTIVE DATE: June 11, 1996.

ADDRESSES: Information pertaining to

this rulemaking action may be examined

at the Federal Aviation Administration

(FAA), Transport Airplane Directorate,

Rules Docket, 1601 Lind Avenue, SW.,

Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

William Schroeder, Aerospace Engineer,

Standardization Branch, ANM–113,

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(206) 227–2148; fax (206) 227–1149.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to

include an airworthiness directive (AD)

that is applicable to all Jetstream Model

4101 airplanes was published in the

Federal Register on January 25, 1996

(61 FR 2142). That action proposed to

require revising the Airplane Flight

Manual (AFM) to specify procedures

that would prohibit flight in freezing

rain or freezing drizzle conditions (as

determined by certain visual cues), limit

or prohibit the use of various flight

control devices, and provide the flight

crew with recognition cues for, and

procedures for exiting from, severe icing

conditions.

Disposition of Comments

For the disposition of comments on

this rulemaking action, see Docket No.

95–NM–146–AD; Amendment 39–9604;

AD 96–09–28, Airworthiness Directives;

Aerospatiale Model ATR–42 and ATR–

72 Series Airplanes, published

elsewhere in this issue of the Federal

Register.
20670 Federal Register / Vol. 61, No. 89 / Tuesday, May 7, 1996 / Rules and Regulations

Conclusion

After careful review of the available

data, including the comments noted

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule with the changes

previously described. The FAA has

determined that these changes will

neither increase the economic burden

on any operator nor increase the scope

of the AD.

Cost Impact

The FAA estimates that 35 airplanes

of U.S. registry will be affected by this

AD, that it will take approximately 1

work hour per airplane to accomplish

the required actions, and that the

average labor rate is $60 per work hour.

Based on these figures, the cost impact

of the AD on U.S. operators is estimated

to be $2,100, or $60 per airplane.

The cost impact figure discussed

above is based on assumptions that no

operator has yet accomplished any of

the requirements of this AD action, and

that no operator would accomplish

those actions in the future if this AD

were not adopted.

In addition, the FAA recognizes that

this AD may impose operational costs.

However, those costs are incalculable

because the frequency of occurrence of

the specified conditions and the

associated additional flight time are

indeterminable. Nevertheless, because

of the severity of the unsafe condition

addressed, the FAA has determined that

continued operational safety

necessitates the imposition of these

costs.

Regulatory Impact

The regulations adopted herein will

not have substantial direct effects 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. Therefore, in

accordance with Executive Order 12612,

it is determined that this final rule does

not have sufficient federalism

implications to warrant the preparation

of a Federalism Assessment.

For the reasons discussed above, I

certify that this action (1) is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under DOT

Regulatory Policies and Procedures (44

FR 11034, February 26, 1979); and (3)

will not have a significant economic

impact, positive or negative, on a

substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A final evaluation has

been prepared for this action and it is

contained in the Rules Docket. A copy

of it may be obtained from the Rules

Docket at the location provided under

the caption ADDRESSES.

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 USC 106(g), 40113, 44701.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

96–09–19 Jetstream Aircraft Limited:

Amendment 39–9595. Docket 96–NM–

14–AD.

Applicability: All Model 4101 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 (b) 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, unless

accomplished previously.

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 the effective date

of this AD, accomplish the requirements of

paragraphs (a)(1) and (a)(2) of this AD.

Note 2: Operators must 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

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 accreted on the

airframe in areas not normally observed to

collect ice.

—Accumulation of ice on the upper surface

of the wing aft of the protected area.

—Accumulation of ice on the propeller

spinner farther aft than normally observed.

• Since the autopilot 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 icing detection lights must be

operative prior to flight into 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

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.
Federal Register / Vol. 61, No. 89 / Tuesday, May 7, 1996 / Rules and Regulations 20671

• 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 during extended

operation 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) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager,

Standardization Branch, ANM–113, FAA,

Transport Airplane Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Operations

Inspector, who may add comments and then

send it to the Manager, Standardization

Branch, ANM–113.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Standardization Branch,

ANM–113.

(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) This amendment becomes effective on

June 11, 1996.

Issued in Renton, Washington, on April 24,

1996.

Ronald T. Wojnar,

Manager, Transport Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 96–10777 Filed 5–1–96; 3:26 pm]

BILLING CODE 4910–13–P

14 CFR Part 39

[Docket No. 96–NM–15–AD; Amendment

39–9596; AD 96–09–20]

RIN 2120–AA64

Airworthiness Directives; British

Aerospace Model HS 748 Series

Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to all British Aerospace

Model HS 748 series airplanes, that

requires revising the Airplane Flight

Manual (AFM) to provide the flight

crew with recognition cues for, and

procedures for exiting from, severe icing

conditions, and to limit or prohibit the

use of various flight control devices.

This amendment is prompted by results

of a review of the requirements for

certification of the airplane in icing

conditions, new information on the

icing environment, and icing data

provided currently to the flight crews.

The actions specified by this AD are

intended 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.

EFFECTIVE DATE: June 11, 1996.

ADDRESSES: Information pertaining to

this rulemaking action may be examined

at the Federal Aviation Administration

(FAA), Transport Airplane Directorate,

Rules Docket, 1601 Lind Avenue, SW.,

Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

William Schroeder, Aerospace Engineer,

Standardization Branch, ANM–113,

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(206) 227–2148; fax (206) 227–1149.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to

include an airworthiness directive (AD)

that is applicable to all British

Aerospace Model HS 748 series

airplanes was published in the Federal

Register on January 25, 1996 (61 FR

2139). That action proposed to require

revising the Airplane Flight Manual

(AFM) to specify procedures that would

prohibit flight in freezing rain or

freezing drizzle conditions (as

determined by certain visual cues), limit

or prohibit the use of various flight

control devices, and provide the flight

crew with recognition cues for, and

procedures for exiting from, severe icing

conditions.

Disposition of Comments

For the disposition of comments on

this rulemaking action, see Docket No.

95–NM–146–AD; Amendment 39–9604;

AD 96–09–28, Airworthiness Directives;

Aerospatiale Model ATR–42 and ATR–

72 Series Airplanes, published

elsewhere in this issue of the Federal

Register.

Conclusion

After careful review of the available

data, including the comments noted

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule with the changes

previously described. The FAA has

determined that these changes will

neither increase the economic burden

on any operator nor increase the scope

of the AD.

Cost Impact

Currently, there are no Model HS 748

series airplanes on the U.S. Register.

However, should an affected airplane be

imported and placed on the U.S.

Register in the future, it would require

approximately 1 work hour to

accomplish the required actions, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of this AD would be $60 per airplane.

In addition, the FAA recognizes that

this AD may impose operational costs.

However, those costs are incalculable

because the frequency of occurrence of

the specified conditions and the

associated additional flight time are

indeterminable. Nevertheless, because

of the severity of the unsafe condition

addressed, the FAA has determined that

continued operational safety

necessitates the imposition of these

costs.

Regulatory Impact

The regulations adopted herein will

not have substantial direct effects 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. Therefore, in

accordance with Executive Order 12612,

it is determined that this final rule does

not have sufficient federalism

implications to warrant the preparation

of a Federalism Assessment.

For the reasons discussed above, I

certify that this action (1) is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under DOT

Regulatory Policies and Procedures (44

FR 11034, February 26, 1979); and (3)

will not have a significant economic

impact, positive or negative, on a

substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A final evaluation has

been prepared for this action and it is

contained in the Rules Docket. A copy

of it may be obtained from the Rules

Docket at the location provided under

the caption ADDRESSES.

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: