[Federal Register Volume 59, Number 81 (Thursday, April 28, 1994)]
[Unknown Section]
[Page ]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-10168]


[Federal Register: April 28, 1994]


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Part VII





Department of Transportation





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Federal Aviation Administration



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14 CFR Part 25



Design Standards for Airplane Jacking and Tie-Down Provision; Final 
Rule
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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. 26129; Amdt. No. 25-81]
RIN 2120-AD38


Design Standards for Airplane Jacking and Tie-Down Provisions

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment to the airworthiness standards for transport 
category airplanes adds a new design standard for airplane jacking and 
tie-down provisions. This amendment is needed to provide manufacturers 
with design standards for jacking conditions and is intended to protect 
primary airplane structure during jacking operations and from gusty 
wind conditions while tied down.

EFFECTIVE DATE: May 31, 1994.

FOR FURTHER INFORMATION CONTACT:
Iven Connally, FAA, Airframe and Propulsion Branch (ANM-112), Transport 
Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue 
SW, Renton, WA 98055-4056; telephone (206) 227-2120.

SUPPLEMENTARY INFORMATION: 

Background

    This amendment is based on Notice of Proposed Rulemaking (NPRM) 90-
3, which was published in the Federal Register on February 9, 1990 (55 
FR 4790). The notice was predicated on a need to protect primary 
airplane structure from damage during jacking operations and during 
gusty wind conditions.
    Airplane jacking is achieved by either lifting on the airframe or 
on the landing gear. In some instances, the airplane has either slipped 
off the jacks or been blown off during gusty wind conditions. Also, 
some transport category airplanes have tie-down provisions to restrain 
the airplane during high wind conditions. Damage to primary structure 
could result if the tie-down provisions were not designed to withstand 
likely wind gusts.
    Most manufacturers of transport category airplanes provide 
information and instructions concerning jacking operations in addition 
to providing appropriate jacking points on the airplane. However, 
currently there is no requirement in the airworthiness standards for 
transport category airplane designs to account for jacking or tie-down 
loads. In the absence of specific standards, some manufacturers have 
used jacking and tie-down criteria contained in military specifications 
to design the airframe and landing gear of commercial transport 
category airplanes. Others, primarily the manufacturers of smaller 
transport category airplanes, have requested design criteria for 
jacking and tie-down loads.
    While the FAA is not aware of any existing airplanes that are 
inadequately designed with respect to jacking and tie-down provisions, 
it is conceivable that an airplane with inadequately designed jacking 
and tie-down provisions may be certificated in the absence of specific 
regulatory requirements. Structural damage at the jacking or tie-down 
points could pose an immediate hazard while the airplane is on the 
ground. Even if an airplane does not fall off the jacks, there is the 
possibility that damage to primary structure could occur from the 
static loads applied at inadequately designed jacking points. In 
addition, there is a danger that the damage could remain undetected and 
lead to a catastrophic structural failure during a subsequent flight. 
Undetected damage from inadequately designed tie-down provisions poses 
a similar hazard.
    These concerns resulted in Notice 90-3 in which the FAA proposed to 
require transport category airplanes to have suitable provisions for 
jacking. In essence, standards consistent with current industry 
practice were proposed to provide protection of primary airplane 
structure from loads imposed during probable jacking conditions. As 
there is no requirement for tie-down provisions, the FAA also proposed 
to adopt standards to provide protection of primary airplane structure 
in the event such provisions are provided. This standard is also 
consistent with current industry practice.
    Interested persons have been given an opportunity to participate in 
this rulemaking and due consideration has been given to all matters 
presented. Comments received in response to Notice 90-3 are discussed 
below.

Discussion of Comments

    The proposed standards are based on established military and 
commercial airplane standards and on current industry practice and 
therefore received general support from all commenters.
    The European Joint Aviation Authorities (JAA) suggest the 
requirements of JAR 25.519 (Joint Airworthiness Requirements) be 
adopted as Sec. 25.519 of the Federal Aviation Regulations (FAR), 
offering as justification the favorable service history associated with 
the JAR.
    The JAR standards differ from the proposals in Notice 90-3 in that 
the load factors used in establishing the vertical and horizontal 
jacking forces are slightly less. The wind force used to establish the 
tie-down loads is also slightly less. Although the JAR standard is less 
conservative than the proposed FAR standard, there is sufficient 
satisfactory service experience based on the requirements of JAR 25.519 
to justify its adoption as the basis for the FAR standard. 
Additionally, some clarifying changes from the current JAR standard are 
made in order to define clearly the structures to which the jacking 
load factors apply. The word ``surrounding'' is changed to ``local'' to 
differentiate between local structure and the entire airplane 
structure. Also, since the maximum design weight, in this case, is the 
maximum ramp weight, the rule is revised to avoid any confusion over 
the weight to use in analyzing the support structure. These minor 
changes in the final rule will more fully harmonize the FAR and JAR 
requirements. The JAA also suggests that the introduction of jacking 
requirements in Sec. 25.513 of the FAR, which corresponds with 
requirements in JAR 25.519, could cause confusion. The FAA agrees, and 
for consistency with the JAR, the jacking requirement has been moved 
from proposed Sec. 25.513 of the FAR to Sec. 25.519.
    One commenter recommends that consideration be given to 
incorporating a design requirement to improve the airplane's ability to 
maintain contact with the jack head. The FAA has determined that the 
high side load requirements for the jack fittings achieves this 
objective and should provide ample protection against an airplane 
slipping off the jacks.
    One commenter recommends the development of standards requiring the 
use of jacks when working on aircraft with known landing gear problems. 
The commenter cites an instance in which an airplane that had made a 
gear up landing was parked with the gear down in an unrepaired 
condition. Two pilots, while inspecting the airplane for damage, were 
crushed when the gear collapsed. The FAA considers the concern 
expressed by the commenter to relate to maintenance or salvage 
procedures. Since such procedures are not the subject of certification 
requirements, they are beyond the scope of the notice.
    One operator suggests that the regulation include a requirement for 
the manufacturer to provide specific jacking requirements in the 
Structural Repair Manual and the Maintenance Manual, and that these 
requirements include specific loads at each jack pad for various empty 
weights and center of gravity locations. The manufacturers generally do 
provide jacking instructions, including jack pad load limits, in the 
maintenance and structural repair manuals which are approved as part of 
the overall maintenance program. While the FAA does not consider it 
necessary to mandate where the manufacturer places this information, 
the final rule has been revised to require that load limit information 
must be provided.

Regulatory Evaluation

    This section summarizes the full regulatory evaluation prepared by 
the FAA that provides more detailed estimates of the economic 
consequences of this regulatory action. This summary and the full 
evaluation quantify, to the extent practicable, estimated costs to the 
private sector, consumers, Federal, State and local governments, as 
well as anticipated benefits.
    Proposed changes to Federal regulations must undergo several 
economic analyses. First, Executive Order 12866 directs that each 
Federal agency shall propose or adopt a regulation only upon a reasoned 
determination that the benefits of the intended regulation justify its 
costs. Second, the Regulatory Flexibility Act of 1980 requires agencies 
to analyze the economic effect of regulatory changes on small entities. 
Third, the Office of Management and Budget directs agencies to assess 
the effects of regulatory changes on international trade. In conducting 
these analyses, the FAA has determined that this rule: (1) Will 
generate benefits that justify its costs and is not a ``significant 
regulatory action'' as defined in the Executive Order, (2) is not 
significant as defined in Department of Transportation Regulatory 
Policies and Procedures; (3) will not have a significant impact on a 
substantial number of small entities; and (4) will not constitute a 
barrier to international trade. These analyses, available in the 
docket, are summarized below.

Benefits

    The FAA is unaware of any existing airplanes that are inadequately 
designed with respect to jacking or tie-down provisions. In the absence 
of specific regulatory standards, it is possible that an airplane with 
inadequate design standards for jacking and tie-down could be 
certificated. Structural damage at the jacking or tie-down points of an 
inadequately designed airplane could pose a hazard while the airplane 
is on the ground. More importantly, structural damage at jacking or 
tie-down points could remain undetected and lead to catastrophic 
structural failure during a subsequent flight. Transport category 
airplanes particularly larger airplanes, seldom need to be tied down 
for protection from high winds. Nevertheless, reliance on inadequately 
designed tie-down provisions could also damage primary structure.
    The FAA is unable to document specific instances where the 
standards of this rule would have prevented damage to the primary 
structure of transport category airplanes, primarily because it is 
assumed that existing airplanes are properly designed with respect to 
jacking and tie-down provisions. However, the FAA considers that the 
potential risk of jacking and tie-down accidents will be reduced for 
future airplane designs that might otherwise be built in the absence of 
the consistent standards of this amendment. Significant but 
unquantified benefits could result from reducing the risk of such 
incidents.

Costs

    Essentially all manufacturers of transport category airplanes 
currently provide appropriate jacking points and jacking instructions 
for their airplanes. In the absence of regulatory standards for jacking 
and tie-down provisions on transport category airplanes, some 
manufacturers have used the jacking and tie-down criteria of military 
specifications for designing the airframes and landing gears of 
commercial transport category airplanes. Others, primarily the 
manufacturers of smaller transport category airplanes, have requested 
design criteria for jacking and tie-down loads.
    The FAA is not aware of any manufacturers who have not used either 
military specifications or other comparable criteria for designing the 
airframe and landing gear. Since all large airplanes must be jacked 
periodically, reasonable and prudent manufacturers have had little 
choice but to follow this course. Because this rule adopts standards 
that are consistent with both current and expected industry practice, 
it is not expected to result in any significant compliance costs.

Comparison of Costs and Benefits

    The FAA is unaware of any existing airplanes that are inadequately 
designed with respect to jacking or tie-down provisions. Since this 
rule adopts the standards that industry has largely followed, and would 
most likely continue to follow, in the absence of this rule, no 
significant costs or benefits are expected.
    In the absence of specific regulatory standards, it is possible 
that an inadequately designed airplane could be certificated. In such a 
case, the benefits of reducing the potential risk of jacking and tie-
down accidents would significantly exceed any incremental costs of 
compliance. As such, the FAA considers this rule to be cost-beneficial.

Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 (RFA) was enacted by 
Congress to ensure that small entities are not unnecessarily and 
disproportionately burdened by government regulations. The RFA requires 
government agencies to review rules which may have ``a significant 
economic impact on a substantial number of small entities.''
    FAA Order 2100.14A, Regulatory Flexibility Criteria and Guidance, 
establishes threshold cost values and small entity size standards for 
complying with RFA review requirements in FAA rulemaking actions. This 
rule will directly affect transport category airplane manufacturers 
that certify their airplanes under part 25. The size standard for 
manufacturers of airplanes is 75 employees of fewer. Since no transport 
category airplane manufacturer meets the standard, this rule will not 
have a significant economic impact on a substantial number of small 
entities.

International Trade Impact Assessment

    This rule is not expected to have an adverse impact either on the 
trade opportunities of U.S. manufacturers of transport category 
airplanes doing business abroad or on foreign airplane manufacturers 
doing business in the United States. Since the certification rules are 
applicable to both foreign and domestic manufacturers selling airplanes 
in the United States, there will be no competitive trade advantage to 
either.

Federalism Implications

    The regulation adopted herein will 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 
regulation will not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.

Conclusion

    Because the regulation adopted herein is not expected to result in 
significant costs, the FAA has determined that this final rule is not a 
significant regulatory action as defined in Executive Order 12866. For 
the same reason and because this is an issue that has not prompted a 
great deal of public concern, this final rule is not considered to be 
significant as defined in Department of Transportation Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). In addition, 
since there are no small entities affected by this rulemaking, it is 
certified, under the criteria of the Regulatory Flexibility Act, that 
this final rule will not have a significant economic impact, positive 
or negative, on a substantial number of small entities. A copy of the 
regulatory evaluation prepared for this final rule may be examined in 
the public docket or obtained from the person identified under the 
caption, for further information contact.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Federal Aviation Administration, 
Reporting and recordkeeping requirements.

Adoption of the Amendment

    Accordingly, 14 CFR part 25 of the Federal Aviation Regulations 
(FAR) is amended as follows:

PART 25--AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES

    1. The authority citation for part 25 continues to read as follows:

    Authority: 49 U.S.C. app. 1344, 1354(a), 1355, 1421, 1423, 1424, 
1425, 1428, 1429, 1430; 49 U.S.C. 106(g); and 49 CFR 1.47(a).

    2. A new Sec. 25.519 is added under the undesignated center heading 
``Ground Loads'' to read as follows:


Sec. 25.519  Jacking and tie-down provisions.

    (a) General. The airplane must be designed to withstand the limit 
load conditions resulting from the static ground load conditions of 
paragraph (b) of this section and, if applicable, paragraph (c) of this 
section at the most critical combinations of airplane weight and center 
of gravity. The maximum allowable load at each jack pad must be 
specified.
    (b) Jacking. The airplane must have provisions for jacking and must 
withstand the following limit loads when the airplane is supported on 
jacks--
    (1) For jacking by the landing gear at the maximum ramp weight of 
the airplane, the airplane structure must be designed for a vertical 
load of 1.33 times the vertical static reaction at each jacking point 
acting singly and in combination with a horizontal load of 0.33 times 
the vertical static reaction applied in any direction.
    (2) For jacking by other airplane structure at maximum approved 
jacking weight:
    (i) The airplane structure must be designed for a vertical load of 
1.33 times the vertical reaction at each jacking point acting singly 
and in combination with a horizontal load of 0.33 times the vertical 
static reaction applied in any direction.
    (ii) The jacking pads and local structure must be designed for a 
vertical load of 2.0 times the vertical static reaction at each jacking 
point, acting singly and in combination with a horizontal load of 0.33 
times the vertical static reaction applied in any direction.
    (c) Tie-down. If tie-down points are provided, the main tie-down 
points and local structure must withstand the limit loads resulting 
from a 65-knot horizontal wind from any direction.

    Issued in Washington, DC, on April 13, 1994.
David R. Hinson,
Administrator.
[FR Doc. 94-10168 Filed 4-26-94; 8:45 am]
BILLING CODE 4910-13-M