
[Federal Register: May 6, 2008 (Volume 73, Number 88)]
[Rules and Regulations]               
[Page 24864-24866]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr06my08-5]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0371; Directorate Identifier 2007-NM-269-AD; 
Amendment 39-15511; AD 2008-10-05]
RIN 2120-AA64

 
Airworthiness Directives; BAE Systems (Operations) Limited Model 
BAe 146 and Model Avro 146-RJ Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from service history of 
incidents and accidents involving transport category turbojet airplanes 
without leading edge high lift devices. This service history shows that 
even small amounts of frost, ice, snow, or slush on the wing leading 
edges or forward upper wing surfaces can cause an adverse change in the 
stall speeds and stall characteristics, and can negate the protection 
provided by a stall protection system. While there have been no 
accidents or incidents related to wing contamination associated with 
the BAE Systems (Operations) Limited Model BAe 146 and Model Avro 146-
RJ airplanes, these airplanes are also transport category turbojet 
airplanes without leading edge high lift devices, and therefore may be 
similarly sensitive to small amounts of wing contamination. This AD 
requires revising the airplane flight manual to include a new cold 
weather operations limitation. We are issuing this AD to prevent 
possible loss of control on takeoff resulting from even small amounts 
of frost, ice, snow, or slush on the wing leading edges or forward 
upper wing surfaces. We are issuing this AD to require actions to 
correct the unsafe condition on these products.

DATES: This AD becomes effective June 10, 2008.

ADDRESSES: You may examine the AD docket on the Internet at http://
www.regulations.gov or in person at the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.

FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, Transport Airplane Directorate, FAA, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
227-1175; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on December 26, 2007 
(72 FR 72968). That NPRM proposed to require revising the airplane 
flight manual to include a new cold weather operations limitation.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We have considered the comment received.

Request to Withdraw NPRM or Revise Paragraph (e)

    BAE Systems (Operations) Limited, type certificate holder for Model 
BAe 146 and Model Avro 146-RJ airplanes, states that it has reviewed 
the NPRM and is preparing advice in an expanded flight crew operations 
manual (FCOM) to explain the importance of a ``clean wing'' prior to 
takeoff. The information in that manual, including the use of tactile 
checks, permits operators and de-/anti-icing service providers to 
develop procedures to suit local arrangements. BAE Systems states that 
this approach is consistent with other regional aircraft types for 
which airplane flight manual (AFM) revisions have not been mandated. 
While BAE Systems fully supports safety initiatives aimed at minimizing 
wing contamination, BAE Systems asserts that a safety concern does not 
exist on the Model BAe 146 and Model Avro 146-RJ airplanes for the 
following reasons:
     No accidents or incidents due to upper surface 
contamination have occurred on Model BAe 146 and Model Avro 146-RJ 
airplanes (this information was not included in the Summary of the 
NPRM).
     The different wing shape on Model BAe 146 and Model Avro 
146-RJ airplanes make them less susceptible to the effects of leading 
edge and upper surface contamination.
     There is no evidence that small/visually imperceptible 
amounts of ice on the wing of these airplanes would lead to loss of 
control during takeoff.
    BAE Systems asks that if we amend 14 CFR part 39 to require the 
additional limitations in the AFM, we revise paragraph (e) ``Reason'' 
of the NPRM to include the words: ``Whilst there is no service history 
that indicates the BAe146 and Avro 146-RJ will be similarly affected. * 
* *''
    We acknowledge BAE Systems' concerns, and partially agree with its 
requests. We agree that no accidents or incidents due to upper surface 
contamination have occurred on Model BAe 146 and Model Avro 146-RJ 
airplanes. We have revised the AD to include that acknowledgement in 
the Summary and in paragraph (e).
    However, we disagree that a safety concern does not exist on the 
Model BAe 146 and Model Avro 146-RJ airplanes and therefore, by 
implication, that we should withdraw the NPRM.
    Section 39.1 of the Federal Aviation Regulations (14 CFR 39.1) 
states:

[[Page 24865]]

    ``This part prescribes airworthiness directives that apply to 
aircraft * * * when--
    (a) An unsafe condition exists in a product; and
    (b) That condition is likely to exist or develop in other products 
of the same type design.''
    The Model BAe 146 and Model Avro 146-RJ airplanes share common type 
design characteristics with airplanes that have been involved in 
takeoff accidents and incidents resulting from small amounts of wing 
leading edge or upper surface contamination. The accident and incident 
history shows that transport category turbojet airplanes without 
leading edge high lift devices have been involved in a number of 
takeoff accidents and incidents where undetected upper wing ice 
contamination has been cited as the probable cause or sole contributing 
factor. Although BAE Systems contends that differences between the 
wings of the Model BAe 146/Avro 146-RJ airplanes and the wings of the 
airplane types involved in the accidents and incidents make the Model 
BAe 146/Avro 146-RJ airplanes less susceptible to the effects of wing 
leading edge and upper surface contamination, BAE Systems has not 
supplied data that directly address the FAA's safety concern. We 
evaluated all relevant information, including information submitted by 
BAE Systems before and after issuance of the NPRM, and determined the 
unsafe condition is likely to exist or develop in Model BAe 146 and 
Model Avro 146-RJ airplanes.
    BAE Systems' proposal to include advice in an expanded FCOM to 
explain the importance of a clean wing prior to takeoff, while 
commendable, is insufficient to address the potential unsafe condition. 
Mandatory tactile checks of the wing leading edges and upper surfaces 
in potential ground icing conditions are needed to address the 
potential unsafe condition, and advice provided in an FCOM is not 
mandatory. An airplane operating limitation provided in the AFM is 
necessary to ensure the tactile check is performed. Contrary to BAE 
Systems' assertion that their proposed FCOM approach is consistent with 
the action taken on some other regional airplane types, the only 
instances where similar operating limitations have not been instituted 
on transport category turbojet airplanes without leading edge high lift 
devices have been where the airplane manufacturer provided data showing 
that adequate safety margins would be retained for takeoffs with small 
amounts of undetected wing upper surface contamination.
    For these reasons we do not find it necessary to withdraw the NPRM 
and we have not changed the AD in this regard. However, under the 
provisions of paragraph (g)(1) of the AD, we will consider requests for 
approval of an alternative method of compliance if sufficient data are 
submitted to substantiate that the alternative method would provide an 
acceptable level of safety.

Request to Revise Number of Airplanes of U.S. Registry

    BAE Systems states that, although the ``Costs of Compliance'' 
section gives realistic costs for revising the AFM, it gives an 
incorrect number of airplanes of U.S. Registry. The NPRM states that 
there is only one affected airplane on the U.S. Register; BAE Systems 
understands that the FAA registry currently shows up to 25 examples of 
the affected airplane types.
    We agree with BAE systems that there are additional U.S.-registered 
airplanes affected by this AD. A detailed review shows that several 
airplanes that appear in certain databases to be U.S.-registered are 
instead registered in other countries. Certain other airplanes have 
been scrapped. Therefore, although there are not 25 U.S.-registered 
airplanes, we do agree that there is more than 1 airplane of U.S. 
registry. Therefore, we have revised the Costs of Compliance to include 
the costs for the 10 airplanes that we estimate are on the U.S. 
Register.

Request to Include Costs for Ongoing Actions

    BAE Systems also states that the ``Costs of Compliance'' section 
excludes any assessment of the ongoing cost to operators for the time 
taken to conduct the visual and tactile pre-flight inspections. BAE 
Systems notes that access to the high wings on these airplanes requires 
a tall ladder and that the inspection will take approximately 30 
minutes. BAE Systems estimates that the conditions where tactile checks 
would be required could exist up to 60 days per year, depending on the 
operator's geographical location and route structure, which could cause 
U.S. operators to incur up to 240 additional work hours per airplane 
per year.
    We disagree with adding costs for the pre-flight check to the AD. 
We recognize that when accomplishing the requirements of any AD, 
operators might incur costs in addition to the direct costs that are 
reflected in the cost analysis presented in the AD preamble. However, 
the cost analysis in AD rulemaking actions typically does not include 
these incidental costs.
    In the case of this AD, for example, the requirements are to revise 
the AFM to include certain information. Further, because ADs require 
specific actions to address specific unsafe conditions, they appear to 
impose costs that would not otherwise be borne by operators. However, 
because of the general obligation of operators to maintain and operate 
their airplanes in an airworthy condition, this appearance is 
deceptive. Attributing those costs solely to the issuance of this AD is 
unrealistic because, in the interest of maintaining and operating safe 
airplanes, prudent operators would accomplish the required actions even 
if they were not required to do so by the AD.
    We have not changed the AD in this regard.

Explanation of Change to Summary

    We have revised the Summary to clarify that not all airplanes are 
equipped with a stall protection system (by using the word ``a'' 
instead of ``the''). We have also clarified that the affected airplanes 
are transport category turbojet airplanes without leading edge high 
lift devices, and therefore may be similarly sensitive to small amounts 
of wing contamination.

Conclusion

    We reviewed the available data, including the comments received, 
and determined that air safety and the public interest require adopting 
the AD with the change described previously. We determined that this 
change will not increase the economic burden on any operator or 
increase the scope of the AD.

Costs of Compliance

    This AD affects about 10 products of U.S. registry. We estimate 
that it takes about 1 work-hour per product to comply with this AD. The 
average labor rate is $80 per work-hour. Based on these figures, we 
estimate the cost of the AD on U.S. operators to be $800, or $80 per 
product.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation Programs'' 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
``Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations

[[Page 24866]]

for practices, methods, and procedures the Administrator finds 
necessary for safety in air commerce. This regulation is within the 
scope of that authority because it addresses an unsafe condition that 
is likely to exist or develop on products identified in this rulemaking 
action.

Regulatory Findings

    We determined that this AD will not have federalism implications 
under Executive Order 13132. This AD will 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.
    For the reasons discussed above, I certify that this AD:
    (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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD Docket.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains the NPRM, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Operations office (telephone (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new AD:

2008-10-05 BAE Systems (Operations) Limited (Formerly British 
Aerospace Regional Aircraft): Amendment 39-15511. Docket No. FAA-
2007-0371; Directorate Identifier 2007-NM-269-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective June 10, 
2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all BAE Systems (Operations) Limited 
Model BAe 146-100A, -200A, and -300A series airplanes, certificated 
in any category; and all Model Avro 146-RJ70A, 146-RJ85A, and 146-
RJ100A airplanes, certificated in any category.

Subject

    (d) Air Transport Association (ATA) of America Code 30: Ice and 
Rain Protection.

Reason

    (e) This AD results from service history of incidents and 
accidents involving transport category turbojet airplanes without 
leading edge high lift devices, that shows that even small amounts 
of frost, ice, snow, or slush on the wing leading edges or forward 
upper wing surfaces can cause an adverse change in the stall speeds 
and stall characteristics, and can negate the protection provided by 
a stall protection system. While there have been no accidents or 
incidents related to wing contamination associated with the BAE 
Systems (Operations) Limited Model BAe 146 and Model Avro 146-RJ 
airplanes, these airplanes are also transport category turbojet 
airplanes without leading edge high lift devices, and therefore may 
be similarly sensitive to small amounts of wing contamination. We 
are issuing this AD to prevent possible loss of control on takeoff 
resulting from even small amounts of frost, ice, snow, or slush on 
the wing leading edges or forward upper wing surfaces.

Actions and Compliance

    (f) Within 14 days after the effective date of this AD, revise 
the Limitations Section of the Airplane Flight Manual (AFM) to 
include the following statement. This may be done by inserting a 
copy of this AD in the AFM.
    ``1. Takeoff is prohibited with frost, ice, snow, or slush 
adhering to the wings, control surfaces, engine inlets, or other 
critical surfaces.
    2. A visual and tactile (hand on surface) check of the wing 
leading edge and the wing upper surface must be performed to ensure 
the wing is free from frost, ice, snow, or slush when the outside 
air temperature is less than 42 degrees F (6 degrees C), or if it 
cannot be ascertained that the wing fuel temperature is above 32 
degrees F (0 degrees C); and
    a. There is visible moisture (rain, drizzle, sleet, snow, fog, 
etc.) present; or
    b. Water is present on the wing; or
    c. The difference between the dew point and the outside air 
temperature is 5 degrees F (3 degrees C) or less; or
    d. The atmospheric conditions have been conducive to frost 
formation.''

    Note 1: When a statement identical to that in paragraph (f) of 
this AD has been included in the general revisions of the AFM, the 
general revisions may be inserted into the AFM, and the copy of this 
AD may be removed from the AFM.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Branch, Transport Airplane Directorate, ANM-116, FAA, 
has the authority to approve AMOCs for this AD, if requested using 
the procedures found in 14 CFR 39.19. Send information to ATTN: Todd 
Thompson, Aerospace Engineer, International Branch, ANM-116, 
Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 227-1175; fax (425) 227-1149. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act, the 
Office of Management and Budget (OMB) has approved the information 
collection requirements and has assigned OMB Control Number 2120-
0056.

Related Information

    (h) None.

Material Incorporated by Reference

    (i) None.

    Issued in Renton, Washington, on April 8, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-9876 Filed 5-5-08; 8:45 am]

BILLING CODE 4910-13-P
