[Federal Register Volume 61, Number 208 (Friday, October 25, 1996)]
[Proposed Rules]
[Pages 55233-55235]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-27394]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-142-AD]
RIN 2120-AA64


Airworthiness Directives; Beech (Raytheon) Model BAe 125-800A and 
Hawker 800 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Beech (Raytheon) Model BAe 125-
800A and Hawker 800 series airplanes, that would have required a 
detailed visual inspection of the fuel feed hose assemblies of the 
auxiliary power unit (APU) to detect overheating, degradation, proper 
routing, and adequate clearance; and the correction of any 
discrepancies found. That proposal was prompted by reports of heat 
damage to the fuel feed hose assembly of the APU due to contact between 
the hose assembly and hot surfaces. This action revises the proposed 
rule by adding a requirement to modify the fuel feed hose of the APU. 
The actions specified by this proposed AD are intended to prevent heat 
damage of the fuel feed hose, which could lead to a possible fire/smoke 
hazard when failure of the hose assembly occurs and consequent fuel 
mist or spray is emitted into the rear equipment bay.

DATES: Comments must be received by November 15, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-142-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Raytheon Aircraft Company, Manager Service Engineering, 
Hawker Customer Support Department, P.O. Box 85, Wichita, Kansas 67201-
0085. This information may be examined at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2797; fax (206) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 95-NM-142-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules 
Docket No. 95-NM-142-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Beech (Raytheon) Model BAe 125-800A and Hawker 800 series 
airplanes, was published as a notice of proposed rulemaking (NPRM) in 
the Federal Register on December 22, 1995 (60 FR 66527). That NPRM 
would have required a one-time detailed visual inspection to:

1. detect overheating or degradation of the hose assemblies;
2. verify proper routing of the fuel feed hose assembly of the 
auxiliary power unit (APU); and
3. verify if adequate clearance (0.5 inch) exists between the hose 
assembly and the left-hand mixer valve/main air valve assemblies and 
associated hot air ducting.

    The NPRM referenced Hawker Service Bulletin SB.49-45, dated May 15, 
1995, as the source of service information containing the procedures 
for accomplishing this inspection.
    That NPRM was prompted by reports of heat damage to the fuel feed 
hose assembly of the APU due to contact between the hose assembly and 
hot surfaces. That condition, if not corrected, could lead to a 
possible fire/smoke hazard when failure of the hose assembly occurs and 
consequent fuel mist or spray emitted into the rear equipment bay.

Actions Since Issuance of Previous Proposal

    Since the issuance of that NPRM, the manufacturer has issued Hawker 
Service Bulletin SB.49-47-25A825A, dated August 1, 1995, which 
describes procedures for modification of the fuel feed hose of the APU. 
The modification involves replacing the existing conduit made from 
vinyl, which can withstand operating temperatures of 80  deg.C, with a 
conduit made from convoluted PTFE, which can withstand temperatures of 
up to 240  deg.C. Accomplishment of the modification will eliminate the 
need for

[[Page 55234]]

the one-time visual inspection. The modification will improve the 
protection of the conduit of the fuel feed hose from heat damage.

Explanation of New Requirements of Proposal

    The FAA finds that the one-time visual inspection procedures, as 
specified in the previously issued proposal, alone do not provide the 
degree of safety assurance necessary to address to unsafe condition. 
The FAA has determined that, in order to adequately address the unsafe 
condition presented by the problems associated with heat damage in the 
subject areas, the proposed rule must be revised to include a 
requirement to modify the fuel feed hose of the APU. The modification 
would be required to be accomplished in accordance with Hawker Service 
Bulletin SB.49-47-25A825A, dated August 1, 1995, described previously. 
Installation of this modification would preclude the need for the one-
time visual inspection.

Conclusion

    Since this change expands the scope of the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.

Cost Impact

    The FAA estimates that 70 Beech (Raytheon) Model BAe 125-800A and 
Hawker 800 series airplanes of U.S. registry would be affected by this 
proposed AD.
    It would take approximately 2 work hours per airplane to accomplish 
the proposed inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the inspection proposed by 
this AD on U.S. operators is estimated to be $8,400, or $120 per 
airplane.
    It would take approximately 4 work hours per airplane to accomplish 
the proposed modification, at an average labor rate of $60 per work 
hour. Required parts would cost approximately $218 per airplane. Based 
on these figures, the cost impact of the proposed AD on U.S. operators 
is estimated to be $32,060, or $458 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed requirements 
of this AD action, and that no operator would accomplish those actions 
in the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

Beech Aircraft Company (Raytheon Aircraft Company): Docket 95-NM-
142-AD.

    Applicability: Model BAe 125-800A (including military variants 
C-29A and U-125) and Hawker 800 series airplanes, constructor's 
numbers 8091 and subsequent; equipped with Turbomach auxiliary power 
unit (APU) (Modification 259404B); 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, unless accomplished 
previously. To prevent heat damage to the fuel feed hose assemblies 
of the auxiliary power unit (APU), which could lead to a possible 
fire/smoke hazard if failure of the hose assembly occurs and fuel 
mist or spar is consequently emitted into the rear equipment bay, 
accomplish the following:
    (a) Within 75 days after the effective date of this AD, perform 
a one-time detailed visual inspection to detect overheating or 
degradation of the hose assemblies; to verify proper routing of fuel 
feed hose assembly of the auxiliary power unit (APU); and to verify 
if adequate clearance (0.5 inch) exists between the hose assembly 
(outlet from the fuel pump box of the APU) and the left-hand mixer 
valve/main air valve assemblies and associated hot air ducting; in 
accordance with Hawker Service Bulletin SB.49-45, dated May 15, 
1995.
    (1) If any overheating or degradation is detected, prior to 
further flight, replace the hose assembly with a new assembly and 
ensure that proper clearance and routing exists, in accordance with 
the service bulletin.
    (2) If the clearance of the hose assembly is improperly routed, 
prior to further flight, re-route the assembly maintaining proper 
clearance, in accordance with the service bulletin.
    (3) If the clearance of the hose assembly is inadequate and the 
hose assembly is properly routed, prior to further flight, adjust 
the hose assembly to achieve the 0.5-inch clearance, in accordance 
with the service bulletin.
    (b) Prior to the accumulation of 200 flight hours after the 
effective date of this AD, modify the fuel feed hose of the APU, in 
accordance with Hawker Service Bulletin SB.49-47-25A825A, dated 
August 1, 1995.
    (c) Accomplishment of the modification of the fuel feed hose of 
the APU in accordance with Hawker Service Bulletin SB.49-47-25A825A, 
dated August 1, 1995, constitutes terminating action for the 
requirements of this AD.
    (d) 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.
    (e) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199

[[Page 55235]]

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.

    Issued in Renton, Washington, on October 18, 1996.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-27394 Filed 10-24-96; 8:45 am]
BILLING CODE 4910-13-U