[Federal Register Volume 67, Number 66 (Friday, April 5, 2002)]
[Proposed Rules]
[Pages 16330-16331]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-8281]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 88-NM-145-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-8 Series 
Airplanes

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 all 
McDonnell Douglas Model DC-8 series airplanes. That action would have 
required incorporation of horizontal stabilizer position information 
into the existing takeoff configuration warning system. Since the 
issuance of the NPRM, the Federal Aviation Administration (FAA) has 
received new data that indicate that the identified unsafe condition 
does not exist. Accordingly, the proposed rule is withdrawn.

FOR FURTHER INFORMATION CONTACT: George Y. Mabuni, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California 
90712-4137; telephone (562) 627-5341; fax (562) 627-5210.

[[Page 16331]]


SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to add a new airworthiness 
directive (AD), applicable to all McDonnell Douglas Model DC-8 series 
airplanes, was published in the Federal Register as a Notice of 
Proposed Rulemaking (NPRM) on November 30, 1988 (53 FR 48499). The 
proposed rule would have required incorporation of horizontal 
stabilizer position information into the existing takeoff configuration 
warning system. That action was prompted by an FAA review of takeoff 
configuration warning systems of large turbofan/turbojet transport 
airplanes. The review revealed that the horizontal stabilizer position 
was not monitored by the takeoff warning system on Model DC-8 series 
airplanes. The proposed actions were intended to prevent an airplane 
from taking off in the wrong takeoff configuration.

Since Issuance of the NPRM

    Since the NPRM was issued, we have engaged in additional research 
into the identified unsafe condition and potentially related accidents 
and found that incorrect loading data--and not unsafe flight crew 
procedures--may have resulted in a miscalculated center of gravity on 
takeoff. Incorrect trim setting was cited or at least suspected as a 
factor in three accidents. There are a number of possible explanations 
for an incorrect trim setting: The pilot may have misread the loading 
data, the company flight operations department may have provided 
incorrect data, or the pilot may have erred in calculating and setting 
the trim. To be effective, an out-of-trim warning system requires 
accurate takeoff data from the pilot; therefore, it is not clear 
whether input error may have been involved or whether any of the 
accidents would have actually been prevented by an out-of-trim warning 
system.
    We find that established crew procedures are sufficient to maintain 
the necessary level of safety. Notwithstanding the three accidents 
discussed above, the remaining service experience on Model DC-8 series 
airplanes (and most other airplanes of that vintage) confirms the 
effectiveness and adequacy of flight crew procedures in ensuring the 
correct takeoff setting of the horizontal stabilizer when the flight 
crew is provided correct information. In light of these findings, we 
have determined that the previously identified unsafe condition does 
not exist--provided the flight crew follows established takeoff 
procedures.
    Furthermore, the economic impact of the proposed AD on operators 
would be significant. Five commenters to the NPRM indicated that 
accomplishment of the actions of the proposed AD would impose a 
significant economic burden. The cost of the modification kits would be 
high because the manufacturer must design, test, and certify the system 
before kits can be made available to the operators. The estimated total 
cost to accomplish the proposed actions would be $149,000 per airplane 
(adjusted for inflation from the date of the proposed AD). In fact, the 
cost of implementing the proposed requirements could exceed the value 
of the entire fleet. In light of our determination that an unsafe 
condition does not exist, we find that the large economic impact to 
mandate incorporation of the proposed system on these airplanes is 
impractical and unjustified.

FAA's Conclusions

    Upon further consideration, we have determined that the unsafe 
condition identified in the proposed AD does not exist. Accordingly, 
the proposed rule is hereby withdrawn.
    Withdrawal of this NPRM constitutes only such action, and does not 
preclude the agency from issuing another action in the future, nor does 
it commit the agency to any course of action in the future.

Regulatory Impact

    Since this action only withdraws a notice of proposed rulemaking, 
it is neither a proposed nor a 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 88-NM-145-
AD, published in the Federal Register on November 30, 1988 (53 FR 
48499), is withdrawn.

    Issued in Renton, Washington, on March 28, 2002.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-8281 Filed 4-4-02; 8:45 am]
BILLING CODE 4910-13-P