[Federal Register Volume 66, Number 165 (Friday, August 24, 2001)]
[Proposed Rules]
[Pages 44560-44561]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-21398]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-47-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (Formerly 
Allison Engine Company) 250-C18 and C-20 Series Turboshaft Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Proposed rule; withdrawal.

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SUMMARY: This action withdraws a notice of proposed rulemaking (NPRM) 
that proposed a new airworthiness directive (AD), applicable to Rolls-
Royce Corporation (formerly Allison Engine Company) 250-C18 and C-20 
series turboshaft engines. That action would have required a one-time 
visual inspection of the fuel nozzle screen for contamination. If 
contamination is found, the proposal would have required, prior to 
further flight, replacement of the fuel nozzle screen with a 
serviceable screen, visual inspection of the entire fuel system for 
contamination, and repair, if necessary. In addition, this proposal 
would have required reporting the results of the one-time inspection to 
the Federal Aviation Administration (FAA) to determine if repetitive 
inspections should be required by further rulemaking. This proposal was 
prompted by a report of fuel system contamination that caused an in-
flight engine shutdown, autorotation, and forced landing. Since the 
issuance of the NPRM, the FAA and Rolls-Royce have determined that 
there have been no additional engine problems reported due to fuel 
nozzle screen contamination. Accordingly, the proposed rule is 
withdrawn.

FOR FURTHER INFORMATION CONTACT: John Tallarovic, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 
2300 E. Devon Ave., Des Plaines, IL 60018; telephone (847) 294-8180, 
fax (847) 294-7834.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to add a new AD that is 
applicable to Rolls-Royce Corporation (formerly Allison Engine Company) 
250-C18 and C-20 series turboshaft engines was published in the Federal 
Register on April 25, 2000 (65 FR 24135). That action proposed to 
require a one-time visual inspection of the fuel nozzle screen for 
contamination. If contamination is found, that proposal would have 
required, prior to further flight, replacement of the fuel nozzle 
screen with a serviceable screen, visual inspection of the entire fuel 
system for contamination, and repair, if necessary. In addition, that 
proposal would have

[[Page 44561]]

required reporting the results of the one-time inspection to the 
Federal Aviation Administration (FAA) to determine if repetitive 
inspections should be required by further rulemaking. The actions 
specified by the proposal were intended to prevent an in-flight engine 
shutdown due to blockage of the fuel nozzle screen, which can result in 
autorotation and forced landing.
    Since the issuance of that NPRM, the FAA and Rolls-Royce have 
determined that there have been no additional engine problems reported 
due to fuel nozzle screen contamination. Rolls-Royce further maintains 
that fuel nozzle contamination is a very rare event, varying between 
zero to 6.5 per 8,000 disassembled nozzles.
    Since this problem first surfaced, Rolls-Royce and the FAA have 
taken the following actions:
     Because most accidents involving fuel nozzle contamination 
have occurred in Hawaii, Rolls-Royce Corporation conducted a training/
fact finding mission to Hawaii in the spring of 1998 to assess the 
situation and to help educate users regarding the proper service of 
engine fuel systems.
     The FAA approved revised maintenance procedures for the 
Rolls-Royce model 250 engines. These procedures clarified the actions 
to be taken when fuel system contamination is suspected.
     Finally, the FAA published Special Airworthiness 
Information Bulletin (SAIB) No. CE-01-10 advising owners and operators 
of Rolls-Royce Corporation model 250-C18 series and 250-C20 series 
engines of the recent changes to the fuel system maintenance on how 
rotorcraft engine fuel nozzle screens be inspected.

Comments Received

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support

    Two commenters either supported the NPRM or were neutral.

Opposition to NPRM

    One commenter points out that there is already a requirement to 
inspect the fuel nozzle screen each 300 hours of operation if there is 
no airframe mounted fuel filter (otherwise inspect it at 1,500 hours); 
a 300 hour requirement to replace the fuel filter, and a 1,000 hour 
requirement to change the fuel control screen. The commenter expresses 
concern that the proposed actions in the NPRM would burden the majority 
of the operators who are already correctly performing the required 
maintenance checks. The FAA agrees and the NPRM is being withdrawn.
    Another comment, by an aircraft owner and repair station owner 
employing over 200 Airframe and Powerplant mechanics, strongly opposes 
the actions proposed in the NPRM. The commenter emphasizes that efforts 
should be put into ensuring that clean fuel is used by operators, 
rather than mandating items that are already clearly covered by the 
Original Equipment Manufacturer's maintenance and operations manuals. 
The comment also notes that the rare cases of contamination they had 
witnessed resulted from operators refueling remotely out of 55-gallon 
drums. The commenter believes that this is an operational issue rather 
than an inherent design flaw with the rotorcraft fuel system. The FAA 
agrees. This observation is consistent with the FAA's inspection 
results confirming that accidents involved cases where the fuel supply 
was a problem (less than optimal conditions).
    The final comment opposing the NPRM is from an owner/operator of 
173 helicopters. This individual also points out that the actions 
proposed in the NPRM were already required by the engine maintenance 
manual. He expresses concern that in the course of complying with the 
proposed actions in the NPRM, mechanics will be removing and 
disassembling thousands of fuel nozzles in the field. It is his 
experience that these nozzles are best taken apart at a repair facility 
where they can be checked for proper reassembly after the inspection. 
Due to the critical nature of the assembly process, slight variations 
in the torque values can have a significant effect on the fuel flow and 
spray pattern of the nozzle. The net result would be an increase in 
service difficulties associated with the fuel nozzle. The FAA agrees 
and the proposed NPRM is being withdrawn.
    After further consideration and review of this data, the FAA has 
determined that the unsafe condition no longer exists and is extremely 
unlikely to develop. Accordingly, the proposed rule is withdrawn.
    Withdrawal of this notice of proposed rulemaking does not preclude 
the agency from issuing another notice in the future, nor does it 
commit the agency to any course of action in the future.
    Since this action only withdraws a notice of proposed rulemaking, 
it is neither a proposed nor final rule, and, therefore, is not covered 
under Executive Order 12866, the Regulatory Flexibility Act, or DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979).

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Withdrawal

    Accordingly, the notice of proposed rulemaking, Docket No. 99-NE-
47, published in the Federal Register on April 25, 2000 (65 FR 24135), 
is withdrawn.

    Issued in Burlington, Massachusetts, on August 16, 2001.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 01-21398 Filed 8-23-01; 8:45 am]
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