AD Amdt-39-10443

final rule

Airworthiness Directives; British Aerospace Model HS 748 Series Airplanes

AD Number
Amdt-39-10443
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. 97-NM-98-AD
FR Citation
63 FR 15751
Technical illustration of an aircraft propeller assembly
Problem area Propeller

Applicability

TypeManufacturerModelDetails
aircraft British 748 Airworthiness Directives; British Aerospace Model HS 748 Series Airplanes

Unsafe Condition

Improper use of the propeller ground beta range during flight can lead to loss of airplane controllability, engine overspeed, and consequent loss of engine power due to power levers positioned below the flight idle stop.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Revise the Airplane Flight Manual (AFM) to modify the flight idle stop positioning limitation and add a statement about the consequences of positioning power levers below the flight idle stop during flight.

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Compliance Time

Before further flight

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Affected Aircraft

British Aerospace Model HS 748 series airplanes

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Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace Model HS 748 series airplanes. This action requires revising the Airplane Flight Manual (AFM) to modify the limitation that prohibits the positioning of the power levers below the flight idle stop during flight, and to add a statement of the consequences of positioning the power levers below the flight idle stop during flight. This amendment is prompted by incidents and accidents involving airplanes equipped with turboprop engines in which the propeller ground beta range was used improperly during flight. The actions specified in this AD are intended to prevent loss of airplane controllability, or engine overspeed and consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.

Document Text

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[Federal Register Volume 63, Number 62 (Wednesday, April 1, 1998)]
[Rules and Regulations]
[Pages 15751-15753]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 98-8540]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-98-AD; Amendment 39-10443; AD 98-07-22]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Model HS 748 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all British Aerospace Model HS 748 series airplanes. This 
action requires revising the Airplane Flight Manual (AFM) to modify the 
limitation that prohibits the positioning of the power levers below the 
flight idle stop during flight, and to add a statement of the 
consequences of positioning the power levers below the flight idle stop 
during flight. This amendment is prompted by incidents and accidents 
involving airplanes equipped with turboprop engines in which the 
propeller ground beta range was used improperly during flight. The 
actions specified in this AD are intended to prevent loss of airplane 
controllability, or engine overspeed and consequent loss of engine 
power caused by the power levers being positioned below the flight idle 
stop while the airplane is in flight.

DATES: Effective April 16, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before June 1, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 97-NM-98-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The information concerning this amendment may be obtained from or 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton,Washington.

FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (425) 
227-2145; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: In recent years, the FAA has received 
reports of 14 incidents and/or accidents involving intentional or 
inadvertent operation of the propellers in the beta range during flight 
on airplanes equipped with turboprop engines. (For the purposes of this 
amendment, beta is defined as the range of propeller operation intended 
for use during taxi, ground idle, or reverse operations as controlled 
by the power lever settings aft of the flight idle stop.)
    Five of the fourteen in-flight beta occurrences were classified as 
accidents. In each of these five cases, operation of the propellers in 
the beta range occurred during flight. Operation of the propellers in 
the beta range during flight, if not prevented, could result in loss of 
airplane controllability, or engine overspeed with consequent loss of 
engine power.
    Communication between the FAA and the public during a meeting held 
on June 11-12, 1996, in Seattle, Washington, revealed a lack of 
consistency of the information on in-flight beta operation contained in 
the FAA-approved Airplane Flight Manual (AFM) for airplanes that are 
not certificated for in-flight operation with the power levers below 
the flight idle stop. (Airplanes that are certificated for this type of 
operation are not affected by the above-referenced conditions.)

FAA's Determinations

    The FAA has examined the circumstances and reviewed all available 
information related to the incidents and accidents described 
previously. The FAA finds that the Limitations Section of the AFM's for 
certain airplanes must be revised to prohibit positioning the power 
levers below the flight idle stop while the airplane is in flight, and 
to provide a statement of the consequences of positioning the power 
levers below the flight idle stop. The FAA has determined that the 
affected airplanes include those that are equipped with turboprop 
engines and that are not certificated for in-flight operation with the 
power levers below the flight idle stop. Since British Aerospace Model 
HS 748 series airplanes meet these criteria, the FAA finds that the AFM 
for these airplanes must be revised to include the limitation and 
statement of consequences described previously.

[[Page 15752]]

U.S. Type Certification of the Airplane

    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. The FAA 
has reviewed all available information, and determined that AD action 
is necessary for products of this type design that are certificated for 
operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, this AD is being issued to prevent loss of 
airplane controllability, or engine overspeed and consequent loss of 
engine power caused by the power levers being positioned below the 
flight idle stop while the airplane is in flight.
    This AD requires revising the Limitations Section of the AFM to 
prohibit the positioning of the power levers below the flight idle stop 
while the airplane is in flight, and to provide a statement of the 
consequences of positioning the power levers below the flight idle stop 
while the airplane is in flight.
    This is considered to be interim action until final action is 
identified, at which time the FAA may consider additional rulemaking.

Cost Impact

    None of the British Aerospace Model HS 748 series airplanes 
affected by this action are on the U.S. Register. All airplanes 
included in the applicability of this rule currently are operated by 
non-U.S. operators under foreign registry; therefore, they are not 
directly affected by this AD action. However, the FAA considers that 
this rule is necessary to ensure that the unsafe condition is addressed 
in the event that any of these subject airplanes are imported and 
placed on the U.S. Register in the future.
    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 charge of $60 per 
work hour. Based on these figures, the cost impact of this AD would be 
$60 per airplane.

Determination of Rule's Effective Date

    Since this AD action does not affect any airplane that is currently 
on the U.S. register, it has no adverse economic impact and imposes no 
additional burden on any person. Therefore, prior notice and public 
procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register.

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and opportunity for public comment, comments are 
invited on this rule. Interested persons are invited to comment on this 
rule by submitting such written data, views, or arguments as they may 
desire. Communications shall identify the Rules Docket number and be 
submitted in triplicate to the address specified under the caption 
ADDRESSES. All communications received on or before the closing date 
for comments will be considered, and this rule may be amended in light 
of the comments received. Factual information that supports the 
commenter's ideas and suggestions is extremely helpful in evaluating 
the effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-98-AD.'' The postcard will be date stamped and 
returned to the commenter.

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 U.S.C. 106(g), 40113, 44701.

Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

98-07-22  British Aerospace Regional Aircraft (Formerly British 
Aerospace, Aircraft Group): Amendment 39-10443. Docket 97-NM-98-AD.
    Applicability: All Model HS 748 series 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 prevent loss of airplane controllability, or engine overspeed 
and consequent loss of engine power caused by the power levers being 
positioned below the flight idle stop while the airplane is in 
flight, accomplish the following:
    (a) Within 30 days after the effective date of this AD, revise 
the Limitations Section of

[[Page 15753]]

the FAA-approved Airplane Flight Manual (AFM) to include the 
following statements. This action may be accomplished by inserting a 
copy of this AD into the AFM.

``Selection of the flight fine pitch stop lever to ``withdrawn'' 
while in flight is prohibited. Such positioning may lead to loss of 
airplane control or may result in an overspeed condition and 
consequent loss of engine power.''

    (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 Maintenance Inspector, 
who may add comments and then send it to the Manager, 
Standardization Branch, ANM-113.

    Note 2: 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 April 16, 1998.

    Issued in Renton, Washington, on March 26, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-8540 Filed 3-31-98; 8:45 am]
BILLING CODE 4910-13-U

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