[Federal Register Volume 60, Number 179 (Friday, September 15, 1995)]
[Proposed Rules]
[Pages 47896-47899]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-22969]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 60, No. 179 / Friday, September 15, 1995 /
Proposed Rules
[[Page 47896]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 94-NM-179-AD]
Airworthiness Directives; Boeing Model 727 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directive (AD), which would have superseded an existing AD that is
applicable to certain Boeing Model 727 series airplanes. The existing
AD currently requires inspections to detect cracks of the elevator rear
spar, and repair, if necessary; and provides for a terminating action
for the inspections. The previously proposed action would have added a
one-time inspection to verify that proper clearance exists between the
shear plate and the radii of the elevator rear spar on airplanes on
which the terminating action had been accomplished. This action revises
the proposed rule by adding new inspections to detect cracks and loose
brackets of the elevator rear spar; adding a new terminating
modification for the inspections; and expanding the applicability of
the rule to include additional airplanes. Additionally, it would
supersede two previously issued AD's. The proposed actions are intended
to prevent cracking in elements of the elevator rear spar assembly,
which could result in excessive free play of the elevator control tab
and possible tab flutter.
DATES: Comments must be received by October 12, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-179-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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle,
Washington 98124-2207. This information may be examined at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington.
FOR FURTHER INFORMATION CONTACT: Walter Sippel, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056; telephone (206) 227-2774; fax (206) 227-1181.
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 94-NM-179-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. 94-NM-179-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 Model 727 series airplanes, was published as a notice of
proposed rulemaking (NPRM) in the Federal Register on December 29, 1994
(59 FR 67238). That NPRM published as Docket 94-NM-179-AD, would have
superseded AD 84-22-02, amendment 39-4951 (49 FR 45743, November 20,
1984) to continue to require repetitive visual inspections to detect
cracks of the elevator rear spar, and repair, if necessary. That NPRM
would have added a one-time inspection to verify that proper clearance
exists between the shear plate and the radii of the elevator rear spar
on airplanes on which the terminating action specified in AD 84-22-02
has been accomplished. That NPRM would have also provided for an
improved modification or repair of the elevator rear spar, which, if
accomplished, would have constituted terminating action for the
repetitive visual inspection requirements. The proposed action was
prompted by reports of cracking in the spar radii at the tab hinge
location of the elevator rear spar on certain airplanes. Cracking in
this area, if not corrected, could result in excessive free play of the
elevator control tab and possible tab flutter.
The FAA issued another proposal, Docket No. 94-NM-197-AD,
applicable to certain Boeing Model 727 series airplanes, which was
published as a NPRM in the Federal Register on January 4, 1995 (60 FR
386). That NPRM proposed to supersede AD 87-24-03, amendment 39-5769
(52 FR 43742, November 16, 1987), and require actions essentially
identical to those previously proposed in Docket No. 94-NM-179-AD. The
only relevant differences are the specific affected airplanes and
certain compliance times.
Since the issuance of those two NPRM's, the FAA has received
several reports of cracking found in the elevator
[[Page 47897]]
rear spar on a number of Model 727 series airplanes. Investigation has
revealed that this cracking occurred on these airplanes following
accomplishment of inspections to ensure that proper clearance exists
between the shear plate and the rear spar radii. Those inspections of
this area would have been required by the two previously-issued NPRM's.
The inspection procedure is described in Boeing Service Bulletin 727-
55-0085 (which was referenced in Docket No. 94-NM-179-AD as the
appropriate source of service information), and Boeing Service Bulletin
727-55-0087 (which was referenced in Docket No. 94-NM-197-AD as the
appropriate source of service information). In light of this new
cracking, the FAA has determined that these inspections to verify
clearance, as proposed in Docket 94-NM-179-AD and Docket 94-NM-197-AD,
do not adequately preclude fatigue cracking in the elevator rear spar;
this condition could result in excessive free play of the elevator
control tab and possible tab flutter.
The FAA has reviewed and approved Boeing Service Bulletin 727-55-
0089, dated June 29, 1995. The service bulletin describes procedures
for repetitive visual inspections to detect cracks and loose brackets
of the elevator rear spar in the area along the upper and lower edges
at the shear plate. This service bulletin also describes procedures for
various follow-on actions, such as stop drilling and modification. The
modification involves replacing the elevator rear spar with a one piece
spar assembly and the tee fittings with two support fittings per tab
hinge bracket. This modification will prevent fatigue cracks in the
elevator rear spar. Accomplishment of the modification eliminates the
need for the repetitive visual inspections.
Additionally, this service bulletin expands the effectivity listing
to include additional airplanes, which were not previously addressed in
Boeing Service Bulletins 727-55-0085 and 727-44-0087, but are subject
to the addressed unsafe condition. (Operators should note that Boeing
Service Bulletin 727-55-0089 supersedes Boeing Service Bulletins 727-
55-0085 and 727-55-0087.)
Since this condition is likely to exist or develop on other
products of this same type design, this supplemental NPRM would
supersede AD's 84-22-02 and 87-24-03, and would require repetitive
visual inspections to detect cracks and loose brackets of the elevator
rear spar, and various follow-on actions. The supplemental NPRM would
also require installation of a modification that would constitute
terminating action for the repetitive inspections. Additionally, the
supplemental NPRM would expand the applicability of the existing
proposed rule to include additional airplanes. These actions would be
required to be accomplished in accordance with Boeing Service Bulletin
727-55-0089, described previously.
The FAA has determined that, in order to adequately address the
unsafe condition presented by the problems associated with fatigue
cracking in the subject areas, and to facilitate recordkeeping by
affected operators, this proposed action (Docket 94-NM-179-AD) will
combine the requirements (and applicability) that were previously
proposed in two separate rulemaking actions. The FAA intends to
withdraw Docket 94-NM-197-AD at a later time by means of a separate
rulemaking action.
Since these changes expand 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.
There are approximately 1,631 Model 727 series airplanes of the
affected design in the worldwide fleet. The FAA estimates that 1,166
airplanes of U.S. registry would be affected by this proposed AD.
The inspections would take approximately 17 work hours per airplane
to accomplish (this includes the time required to gain access, remove
parts, inspect, install, and perform functional testing), at an average
labor rate of $60 per work hour. Based on these figures, the total cost
impact of the proposed inspections requirements on U.S. operators is
estimated to be $1,189,320, or $1,020 per airplane, per inspection
cycle.
The modification would take approximately 430 work hours per
airplane to accomplish, at an average labor rate of $60 per work hours.
Required parts would cost approximately $8,580 per airplane. Based on
these figures, the total cost impact of the proposed modification
requirements on U.S. operators is estimated to be $40,087,080, or
$34,380 per airplane.
The total 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.
The FAA recognizes that the obligation to maintain aircraft in an
airworthy condition is vital, but sometimes expensive. Because AD's
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
aircraft 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 safe aircraft,
prudent operators would accomplish the required actions even if they
were not required to do so by the AD.
A full cost-benefit analysis has not been accomplished for this
proposed AD. As a matter of law, in order to be airworthy, an aircraft
must conform to its type design and be in a condition for safe
operation. The type design is approved only after the FAA makes a
determination that it complies with all applicable airworthiness
requirements. In adopting and maintaining those requirements, the FAA
has already made the determination that they establish a level of
safety that is cost-beneficial. When the FAA, as in this proposed AD,
makes a finding of an unsafe condition, this means that the original
cost-beneficial level of safety is no longer being achieved and that
the proposed actions are necessary to restore that level of safety.
Because this level of safety has already been determined to be cost-
beneficial, a full cost-benefit analysis for this proposed AD would be
redundant and unnecessary.
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
[[Page 47898]]
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), 40101, 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendments 39-4951 (49 FR
45743, November 20, 1984) and 39-5769 (52 FR 43742, November 16, 1987),
and by adding the following new airworthiness directive:
Boeing: Docket 94-NM-179-AD. Supersedes AD 84-22-02, amendment 39-
4951; and AD 87-24-03, amendment 39-5769.
Applicability: Model 727 series airplanes, line numbers 1
through 1832 inclusive; 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 use the authority
provided in paragraph (j) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in this AD. Such
a request should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent excessive free play of the elevator control tab and
possible tab flutter, accomplish the following:
(a) For airplanes on which the modification or repair described
in Boeing Service Bulletin 727-55-0085, dated August 31, 1984
(specified as terminating action in AD 84-22-02, amendment 39-4951),
has not been accomplished and the repetitive inspections required by
AD 84-22-02 have not been initiated: Prior to the accumulation of
8,000 total flight hours since date of manufacture, or within 300
flight hours after the effective date of this AD, whichever occurs
later, accomplish paragraph (g) of this AD.
Note 2: AD 84-22-02 pertains to the one-piece elevator rear
spar.
(b) For airplanes on which the modification or repair described
in Boeing Service Bulletin 727-55-0085, dated August 31, 1984
(specified as terminating action in AD 84-22-02, amendment 39-4951),
has not been accomplished and the repetitive inspections required by
AD 84-22-02 have been initiated: Accomplish either paragraph (b)(1)
or (b)(2) of this AD, as applicable.
(1) If any crack has been stop drilled in accordance with AD 84-
22-02, accomplish paragraphs (b)(1)(i) and (b)(1)(ii) of this AD, in
accordance with Boeing Service Bulletin 727-55-0089, dated June 29,
1995.
(i) Within 1,600 flight hours after stop drilling, accomplish
paragraph (g) of this AD.
(ii) Notwithstanding paragraph (h) of this AD, within 3,200
flight hours after stop drilling, modify the elevator rear spar in
accordance with Part II of the Accomplishment Instructions of the
service bulletin.
(2) If no crack has been detected as a result of inspections
required by AD 84-22-02, within 1,600 flight hours after the last
inspection required by that AD, perform a visual inspection to
detect cracks and loose brackets of the elevator rear spar in the
area along the upper and lower edges at the shear plate, and
accomplish follow-on actions (i.e., stop drill, modify), in
accordance with the Boeing Service Bulletin 727-44-0089, dated June
29, 1995. Repeat the inspection thereafter at intervals not to
exceed 1,600 flight hours or 18 months, whichever occurs first. If
any crack growth is detected after stop drilling, prior to further
flight, modify the elevator rear spar in accordance with Part II of
the Accomplishment Instructions of Boeing Service Bulletin 727-44-
0089, dated June 29, 1995.
(c) For airplanes on which the modification or repair described
in Boeing Service Bulletin 727-55-0085, dated August 31, 1984
(specified as terminating action in AD 84-22-02, amendment 39-4951),
has been accomplished: Within 4,000 flight hours after the effective
date of this AD, accomplish paragraph (g) of this AD.
(d) For airplanes on which the modification or repair described
in Boeing Service Bulletin 727-55-087, dated June 20, 1986
(specified as terminating action in AD 87-24-03, amendment 39-5769),
has not been accomplished and the repetitive inspections required by
AD 87-24-03 have not been initiated: Accomplish paragraph (g) of
this AD, at the earliest of times specified in paragraph (d)(1),
(d)(2), or (d)(3):
Note 3: AD 87-24-03 pertains to the two-piece elevator rear
spar.
(1) Prior to the accumulation of 27,000 total flight hours since
date of manufacture, or within 4,000 flight hours after December 24,
1987 (the effective date of 87-24-03, amendment 39-5769), whichever
occurs later; or
(2) Prior to the accumulation of 12,000 total flight hours since
date of manufacture, or within 4,000 flight hours after the
effective date of this AD, whichever occurs later; or
(3) Prior to the accumulation of 27,300 total flight hours since
date of manufacture, or within 300 flight hours after the effective
date of this AD, whichever occurs later.
(e) For airplanes on which the modification or repair described
in Boeing Service Bulletin 727-55-087, dated June 20, 1986
(specified as terminating action in AD 87-24-03, amendment 39-5769),
has not been accomplished and the repetitive inspections required by
AD 87-24-03 have been initiated: Accomplish either paragraph (e)(1)
or (e)(2) of this AD, as applicable.
(1) If any crack has been stop drilled in accordance with AD 87-
24-03, accomplish paragraphs (e)(1)(i) and (e)(1)(ii) of this AD, in
accordance with Boeing Service Bulletin 727-55-0089, dated June 29,
1995.
(i) Within 1,600 flight hours after stop drilling, accomplish
paragraph (g) of this AD.
(ii) Notwithstanding paragraph (h) of this AD, within 3,200
flight hours after stop drilling, modify the elevator rear spar in
accordance with Part II of the Accomplishment Instructions of the
service bulletin.
(2) If no crack has been detected as a result of inspections
required by AD 87-24-03, within 4,000 flight hours after the last
inspection required by that AD, perform a visual inspection to
detect cracks and loose brackets of the elevator rear spar in the
area along the upper and lower edges at the shear plate, and
accomplish follow-on actions (i.e., stop drill, modify), in
accordance with Boeing Service Bulletin 727-44-0089, dated June 29,
1995. Repeat the inspection thereafter at intervals not to exceed
1,600 flight hours or 18 months, whichever occurs first. If any
crack growth is detected after stop drilling, prior to further
flight, modify the elevator rear spar in accordance with Part II of
the Accomplishment Instructions of Boeing Service Bulletin 727-44-
0089, dated June 29, 1995.
(f) For airplanes on which the modification or repair described
in Boeing Service Bulletin 727-55-087, dated June 20, 1986
(specified as terminating action in AD 87-24-03, amendment 39-5769),
has been accomplished: Within 4,000 flight hours after the effective
date of this AD, accomplish paragraph (g) of this AD.
(g) At the time specified in paragraphs (a), (b)(1)(i), (c),
(d), (e)(1)(i), and (f), as applicable, perform a visual inspection
to detect cracks and loose hinge brackets of the elevator rear spar
in the area along the upper and lower edges at the shear plate, and
accomplish follow-on actions (i.e., re-inspect, stop drill, modify)
in accordance with Boeing Service Bulletin 727-55-0089, dated June
29, 1995, at the time specified in the service bulletin. If any
crack growth is detected after stop drilling, prior to further
flight, modify the elevator rear spar in accordance with Part II of
the Accomplishment Instructions of Boeing Service Bulletin 727-55-
0089, dated June 29, 1995. Accomplishment of the modification
constitutes terminating action for the repetitive inspection
requirements of this AD.
(h) Within 5 years after accomplishing the initial inspection
required by this AD, modify the elevator rear spar in accordance
with Part II of the Accomplishment
[[Page 47899]]
Instructions of Boeing Service Bulletin 727-55-0089, dated June 29,
1995. Accomplishment of the modification constitutes terminating
action for the repetitive inspection requirements of this AD.
(i) 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.
(j) 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, Seattle Aircraft Certification
Office (ACO), 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, Seattle ACO.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
Issued in Renton, Washington, on September 11, 1995.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-22969 Filed 9-14-95; 8:45 am]
BILLING CODE 4910-13-U
