[Federal Register Volume 61, Number 119 (Wednesday, June 19, 1996)]
[Rules and Regulations]
[Pages 31324-31329]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-14083]
[[Page 31323]]
_______________________________________________________________________
Part IV
Department of Transportation
_______________________________________________________________________
Federal Aviation Administration
_______________________________________________________________________
14 CFR Parts 1 and 33
Airworthiness Standards: Aircraft Engines New One-Engine-Inoperative
(EOI) Ratings, Definitions and Type Certification Standards; Final Rule
Federal Register / Vol. 61, No. 119 / Wednesday, June 19, 1996 /
Rules and Regulations
[[Page 31324]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Parts 1 and 33
[Docket No. 26019; Amendment Nos. 1-46, 33-18]
RIN 2120-AD21
Airworthiness Standards: Aircraft Engines New One-Engine-
Inoperative (OEI) Ratings, Definitions and Type Certification Standards
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This amendment establishes definitions for new one-engine
inoperative (OEI) ratings, and type certification standards for those
ratings. This amendment is the result of a petition for rulemaking from
Aerospace Industries Association of America, Inc. (AIA), and a
recognition by both the FAA, along with other civil airworthiness
authorities, and the aviation industry for a need for additional OEI
power rating standards. The maximum engine power rating for rotorcraft
available under current certification standards contained in the
Federal Aviation Regulations (FAR's) is the 2\1/2\-minute OEI rating.
This amendment establishes definitions and type certification standards
for the 30-second OEI and 2-minute OEI rating at higher power levels
than currently available. These new ratings will enhance rotorcraft
safety after an engine failure or precautionary shutdown by providing
the availability for higher OEI power. The benefits from this amendment
are enhanced safety through improved rotorcraft takeoff and landing
performances, and shorter field operations or higher payload with the
same degree of safety.
EFFECTIVE DATE: August 19, 1996.
FOR FURTHER INFORMATION CONTACT:
Chung C. Hsieh, Aerospace Engineer, Engine and Propeller Standards
Staff, ANE-110, Engine and Propeller Directorate, Aircraft
Certification Service, FAA, 12 New England Executive Park, Burlington,
MA 01803-5229, telephone (617) 238-7115; fax (617) 238-7199.
SUPPLEMENTARY INFORMATION:
Background
The FAA issued a Notice of Proposed Rulemaking (NPRM) No. 89-27
that was published in the Federal Register on September 22, 1989 (54 FR
39080), and also issued Supplemental Notice of Proposed Rulemaking
(SNPRM) No. 89-27A that was published in the Federal Register on
February 7, 1995 (60 FR 7380). These notices proposed to define new
one-engine inoperative (OEI) ratings for rotorcraft engines and
establish type certification standards for these new OEI ratings. The
new OEI ratings will be applicable to turbine engines installed on
multiengine powered rotorcraft.
The payload for multiengine rotorcraft is limited by the power
available from the remaining operating engine(s) in the event one
engine fails during takeoff or landing. Currently, the maximum engine
power rating available for rotorcraft under part 33 is the 2\1/2\ OEI
rating. This amendment establishes 30-second OEI and 2-minute OEI
ratings at higher power level than currently available. The new rating
will allow rotorcraft to carry higher payloads from existing fields or
to takeoff from smaller fields with current payloads, without
decreasing the level of safety for these operations. Engine type
certification using these new ratings, however, as with other OEI
ratings, remains optional.
The Aerospace Industries Association of America, Inc., (AIA)
submitted a petition for rulemaking to the FAA on September 20, 1984,
requesting an amendment of the FAR's to permit type certification of
engines and rotorcraft with new OEI ratings. The FAA acknowledged
receipt of the AIA petition, by letter on November 26, 1984, and issued
a notice of that petition that was published in the Federal Register on
December 10, 1984 (49 FR 48759). The FAA subsequently held the petition
in abeyance pending AIA's submission of a revised petition for
rulemaking on April 1, 1987.
The AIA then sponsored a meeting with the Association European des
Constructeurs de Materiel d'Aerospatial (AECMA), the European
Helicopter Association (EHA), and the European Joint Airworthiness
Authorities (JAA) on April 9, 1987, and invited the FAA to attend. The
purpose of this meeting was to familiarize the European community with
the AIA petition. Thereafter, the FAA and the JAA convened their annual
harmonization meeting on May 19-21, 1987, to discuss, in part, the
status of programs of mutual interest. One result of the FAA/JAA
meeting was a recommendation that the FAA and the JAA should strive to
promulgate more harmonious rules and guidance material. Accordingly,
the FAA coordinated their reviews of the AIA petition directly with the
JAA. A meeting was held in late August 1987 between representatives of
the FAA and the JAA to discuss the JAA's concerns with the AIA
petition. The JAA provided many comments, most of which contained
significant deviations from specifies of the petition being considered.
On November 19, 1987, AIA, AECMA, and EHA jointly sponsored a
meeting at AIA Headquarters in Washington, DC, and invited the FAA and
the JAA to attend. The purpose of this meeting was for industry, AIA,
AECMA, and EHA, to jointly address and respond to the comments and
concerns previously expressed by the JAA. In follow-up to this meeting,
on June 8, 1988, the AIA submitted additional revisions to their
petition for rulemaking.
The FAA then issued a final rule from a previous proposal amending
parts 1 and 33 of the FAR's. Amendments 1-34 and 33-12 were issued and
published in the Federal Register on September 2, 1988 (53 FR 34196,
effective October 3, 1988), which redefined OEI ratings in part 1 and
added the Continuous OEI rating in both part 1 and part 33.
After reviewing the revised AIA petition, and coordinating with the
JAA, the FAA issued NPRM No. 89-27 (54 FR 39080), to address the part
33 engine certification aspects of 39-second and 2-minute OEI ratings,
and NPRM No. 89-26 (54 FR 39086), to address the part 27 and part 29
rotorcraft certification aspects of the OEI ratings. Both NPRM's were
published in the Federal Register on September 22, 1989. During the
comment period, the FAA held a joint public meeting to discuss the
proposals of both NPRM's in Fort Worth, Texas, on November 16, 1989
(see Notice of public meeting published on October 13, 1989, 54 FR
41986). The Final rules to part 27 and part 29 were published in the
Federal Register on September 16, 1994 (59 FR 47764).
Based on the comments received, the FAA determined that the
proposals contained in NPRM 89-27 warranted further consideration.
Substantive changes were made to the proposed rule, and SNPRM 89-27A
was published in the Federal Register on February 7, 1995 (60 FR 7380).
The SNPRM gave all interested parties an opportunity to comment on the
modified proposed rule.
All interested persons have been given an opportunity to
participate in this rulemaking, and due consideration has been given to
all matters presented. Some minor editorial changes have been made to
clarify the proposals as indicated herein. The changes are based on
comments received and further FAA review of the proposals. The FAA has
determined that certain technical issues associated with proposed
revisions to Sec. 33.27 have not been resolved. These
[[Page 31325]]
technical issues will be discussed in an Aviation Rulemaking Advisory
Committee (ARAC) working group (see Notice of establishment of
Propulsion Harmonization Working Group at 57 FR 58840, December 11,
1992). Except for the proposed revisions to Sec. 33.27 and other
changes as indicated herein, the proposals contained in SNPRM 89-27A
have been adopted without change.
Discussion of Comments
The commenters represent domestic and foreign engine manufacturers,
and foreign civil airworthiness authorities. Four commenters provided
the FAA with comments to NPRM 89-27, addressing numerous issues. The
FAA also received comments to SNPRM 89-27A from three commenters. This
discussion addresses all the comments made to SNPRM 89-27A, plus those
comments made to NPRM 89-27 that were not already addressed in the
discussion section of SNPRM 89-27A. Some comments presented orally at
the November 16, 1989, public meeting have not been addressed here,
since they have been withdrawn; other oral comments were submitted in
writing to the rules docket. The transcript of the public meeting is in
the Rules Docket. The comments are grouped according to the applicable
sections of the proposed amendment, with general comments discussed
first.
General Comments
One commenter recommends that the FAA should publish the proposals
as worded in the SNPRM as a final rule for all applicable 14 CFR part 1
and 33 sections, with the exception of the proposed revisions to
Sec. 33.27.
One commenter states that the new structure of helicopter engine
ratings as proposed creates a new certification scheme for helicopters
and, accordingly, all the pertinent regulatory and advisory matter must
be considered at the same time. The commenter points out that guidance
material for the proposed ratings, including the maintenance inspection
requirements under Sec. 33.90 and on the issue of power assurance, is
not available. Therefore, the commenter states that an acceptable level
of safety cannot be achieved until all advisory and regulatory material
can be reviewed at the same time.
The FAA disagrees. Even though specific advisory material that
addresses the new OEI ratings is not yet available, the FAA will not
delay issuing this Final rule. The existing guidance material on the
issue of power assurance, which is a certification requirement of the
helicopter under Secs. 27.45(f) and 29.45(f), may be of assistance to
applicants for type certification. A joint effort between the FAA's
Engine & Propeller Directorate and the Rotorcraft Directorate, and both
the engine and the helicopter industry, has resulted in a report
published by the Society of Automotive Engineers (SAE), Aerospace
Information Report AIR4083, ``Helicopter Power Assurance,'' dated July
13, 1989. Also, guidance material addressing the existing Sec. 33.90 is
provided in FAA Advisory Circular (AC) AC 33-2B, ``Aircraft Engine Type
Certification Handbook''. This AC will be revised to include guidance
material on power assurance and mandatory maintenance requirements for
the new OEI ratings following the adoption of this Final rule. The FAA
plans to issue advisory material for these new OEI ratings as soon as
practical.
The commenter also states that this rulemaking is based on an
assumption that the new OEI ratings will be used only during the
takeoff and landing phases of flight. The commenter speculates that it
would be possible that these new ratings be utilized under the
``External Load Operations'' provisions of Sec. 133.45(e)(1). The
commenter suggests that the Regulatory Evaluation section needs to
address whether this assumption will be invalidated if the enhanced OEI
performance is taken into account for other than takeoff and landing
purposes.
The FAA disagrees. While the proposed new OEI ratings are intended
to be used only after the failure of one engine on a multiengine
rotorcraft during takeoff, climb, or landing, it is entirely possible
that these new ratings might be utilized to meet the provisions of
current Sec. 133.45(e)(1), if the rotorcraft and the operator fulfill
those criteria. Therefore, the Regulatory Evaluation does not depend on
how the higher power levels associated with the new OEI ratings may be
used in showing compliance with an existing regulation. In addition the
commenter does not suggest any changes to the regulatory language of
the proposed amendment to part 1 or part 33 to address that concern.
These new ratings are intended to supplement the existing OEI rating
structure for the type certification of engines and rotorcraft.
Existing rotorcraft operating rules with respect to OEI conditions
should not be impacted by the addition of the 30-second and the 2-
minute OEI ratings.
Section 1.1 Definitions
One commenter recommends that the existing Sec. 1.1 definition of
rated 30-minute OEI power should be amended to clarify that the period
of use must not exceed a total of 30 minutes during any flight. The
commenter further states that many authorities are aware of instances
of misinterpretations, not precluded by Flight Manuals, whereby more
than 30 minutes of 30-minute OEI power could have been accumulated
during one flight. This commenter also recommends that the common
aspects of all existing and proposed definitions of rated power/thrust
be expressed in identical language to eliminate differences as much as
possible.
The FAA disagrees. The existing Sec. 1.1 definition of rated 30-
minute OEI power states that the engine power at this rating is limited
in use to a period of not more than 30 minutes after the failure of one
engine of a multiengine rotorcraft. The language used to define the new
30-second OEI and 2-minute OEI ratings is consistent with this and
other OEI definitions. The recommendations on the existing definitions
of rated power and thrust are beyond the scope of this rulemaking. Such
a change may be considered, however, as part of the Engine & Propeller
Directorate's ongoing study on engine ratings.
Section 33.14 Start-Stop Cyclic Stress
One commenter states that the proposal should also include a change
to existing Sec. 33.14 that would exclude OEI ratings from the meaning
of the term ``maximum rated power'' as it appears in Sec. 33.14. The
commenter bases the need for this change on an interpretation of the
existing Sec. 33.14 using the preambles to two previous amendments to
the FAR's, both pre-dating the most recent changes to parts 1 and 33
relating to OEI ratings. The commenter concludes that the suggested
changes would make Sec. 33.14 more rational and provide clarity to
promote consistent application. The commenter also states that
Sec. 33.14 should address rotational speed operating limits and rotor
temperatures in addition to rated powers/thrusts.
The FAA disagrees. No changes to Sec. 33.14 were proposed in either
NPRM No. 89-27 or SNPRM 89-27A. The FAA finds that the existing
Sec. 33.14 is adequate to address the new 30-second OEI and 2-minute
OEI ratings.
Section 33.27 Turbine, Compressor, Fan and Turbosupercharger Rotors
Several commenters state that proposed revisions to Sec. 33.27,
rotor integrity, are not consistent with the status of the discussions
on rotor integrity requirements currently ongoing in an ARAC working
group.
The FAA agrees that proposed Sec. 33.27 is not harmonized with JAR-
E. The proposed revision to Sec. 33.27 has been
[[Page 31326]]
removed from the Final rule as the proposal has not been completely
harmonized by the FAA (part 33) and the JAA (JAR-E). However, the FAA
will consider additional amendments to Sec. 33.27, and ARAC
harmonization is anticipated. In the interim the FAA will address each
application for type certification that requests 30-second OEI and 2-
minute OEI ratings on a case by case basis.
Section 33.29 Instrument Connection
One commenter states that Sec. 29.1305(a)(24) requires an
indication to the pilot when the use of OEI rating begins and when the
allowed time of this rating has expired, and the proposed 33.29(c)(1)
should have consistent requirements.
The FAA agrees. New Sec. 33.29(c)(1) is changed accordingly. In
addition, new Sec. 33.29(c)(3) is changed to clarify the FAA's intent
to require that each usage of a power level at one of the new OEI
ratings is limited in duration. Therefore, for example, as the
definition of the rating provides, 30-second OEI power is limited to
three periods of use in any one flight following an engine failure, and
each period of use is limited to no more than 30 seconds. Unused time
from one period of use may not be accumulated for use during a
subsequent period. Accordingly, new Sec. 33.29(c)(3) is changed to
provide for a means to record each use and the duration of each use of
power at each rating.
Section 33.85 Calibration Tests
One commenter states that the reference in proposed Sec. 33.85(d)
to Secs. 33.87(f) (1) through (8) should read Sec. 33.87, because
paragraphs (1) through (8) of proposed Sec. 33.87(f) relate only to the
new 30-second OEI and 2-minute OEI ratings where proposed Sec. 33.85(d)
is also applicable to the 2\1/2\-minute OEI rating.
The FAA disagrees. New Sec. 33.85(d) is intended for 30-second OEI
and 2-minute OEI ratings only, and reference to the 2\1/2\-minute OEI
rating was accidentally included in the SNPRM. Therefore, the reference
to the 2\1/2\- minute OEI rating is removed from new Sec. 33.85(d).
Section 33.87 Endurance Test
One commenter questions whether, during the additional endurance
testing introduced by proposed Sec. 33.87 (f)(1) through (f)(8), at
least 100 percent of 30-second OEI and 2-minute OEI rated powers must
be produced during all such operations. The commenter states that it
appears to be the intent because Sec. 33.87(a)(3) remains applicable to
the proposed Sec. 33.87(f), yet the commenter states that 100 percent
power may only be required for the first sequence of proposed
Sec. 33.87(f), and not for all the sequences.
The FAA disagrees. The 100 percent rule of Sec. 33.87(a)(3) applies
to new Sec. 33.87(f) for all sequences; no exceptions are intended or
implied.
One commenter suggests the following for proposed Sec. 33.87 (f)(1)
through (f)(8):
1. The test sequence described by Sec. 33.87 (f)(1) through (f)(8)
would be required to be repeated eight times for a total time of not
less than 180 minutes and would be required to be conducted in a
prescribed sequence and without stopping during the 180 minutes total
test period.
2. The sequence during which the length of the particular test
condition defined by Sec. 33.87(f)(4) is increased to sixty-five
minutes would need to be re-defined as: ``except that during the fourth
or fifth test sequence this period shall be sixty-five minutes.''
The FAA disagrees. The two hour supplementary test is to simulate a
flight scenario using 30-second and 2-minute OEI ratings. After the
initial 30-second and 2-minute applications to complete the takeoff or
effect a rejected takeoff and the climb out to a safe altitude and
airspeed, the engine is run at the 30-minute or continuous OEI rating
power to maintain a safe altitude enroute and to complete a landing of
the aircraft. The two hour cyclic test defined in this section
demonstrates the ability of the engine to complete a safe flight with
up to three applications of the 30-second and 2-minute OEI ratings
during one flight. The proposed changes from the commenter are not
supported by reasonable technical justification.
Section 33.88 Engine Overtemperature Test
One commenter suggests that the words ``steady state'' be inserted
before the words ``power-on r.p.m.'' in proposed Sec. 33.88(c). The
commenter states that the words are necessary since the test is
conducted at maximum steady state rpm limit rather than maximum
transient rpm limit. In addition, the proposed change to ``steady
state'' rpm limit and to the post test acceptance criteria is also
applicable to engines not having automatic temperature limiting which
are tested at 75 deg.F above the maximum temperature limit.
The FAA disagrees. The overtemperature condition associated with
usage of the 30-second OEI rating is normally expected from over-
fueling and consequently is accompanied by an excess rpm, not a steady
state level associated with a non-overtemperature or a non-overboost
condition.
One commenter states that use of the words ``provides an exception
from the existing requirements'' in the preamble for Proposal No. 10 of
NPRM 89-27, published September 22, 1989, concerning proposed
Sec. 33.88, could be misconstrued, and that it would have been better
to state `` * * * provides for an alleviation from the rotational speed
and the gas temperature prescribed by the existing requirements* * *.''
The FAA disagrees. The commenter does not suggest any changes to
proposed Sec. 33.88 and the editorial comment addresses the wording
preference in the preamble only.
One commenter states that the last sentence of proposed
Sec. 33.88(c) should read as follows: ``Following this run, the turbine
assembly may exceed serviceable limits, provided there is no evidence
of imminent failure. The applicant may be required to show there is no
evidence of imminent failure by analysis or test''. Another commenter
states that current JAR-E has no direct equivalent to the 5 minute
tests of either the existing Sec. 33.88 or proposed Sec. 33.88(a).
Proposed Sec. 33.88 (b) and (c), which make provision for 5 minute or 4
minute over-temperature test for 30-second OEI ratings, will be
considered by the JAA as a possible basis for a revision to JAR-E.
However, this will be in addition to complying with the existing
turbine rotor overtemperature requirement of JAR-E, C4-6, paragraph 22.
The commenter also suggests that proposed Sec. 33.88 (b) and (c) should
include a requirement that the worst case intended flight profile must
be assumed to include at least a further two applications of 30-second
OEI power, each followed by an application of 2 minute OEI power for
consistency of interpretation and compatibility with usage rational for
these particular OEI ratings, as stated in the ``Background'' of NPRM
89-27.
The FAA disagrees. The intent of the post-test requirements is to
assure that after the overtemperature test, the engine is suitable for
continued service use to complete the worst case intended flight
profile associated with the application of the 30-second OEI power
rating. Although the worst case scenario may include at lease two
additional applications of both 30-second OEI power and 2-minute OEI
power, the last sentence of revised Sec. 33.88(b) and revised
Sec. 33.88(c) will permit the FAA, on a case by case assessment, to
apply the best engineering judgment for each given engine type design
tested.
[[Page 31327]]
Two commenters state that the FAA is proposing a certification
standard for rotorcraft engines with a temperature limiter that differs
from the standard for all other type engines. The commenters conclude
that if a temperature limiter principle is acceptable for rotorcraft
engines, it should also be acceptable for other gas turbine engines and
for other engine ratings. Therefore, the proposal should be changed to
apply generally and not just to 30-second and 2-minute OEI ratings.
The FAA disagrees. The FAA considers that this comment is beyond
the scope of this rulemaking, which addresses only certification
standards for rotorcraft engines. The FAA may consider further
rulemaking to revise Sec. 33.88 for other gas turbine engine
certifications.
One commenter states that the overtemperature subject has been
incorporated into the harmonization effort and requests that the FAA
clearly indicate the intent to harmonize certification standards
related to overtemperature.
The FAA agrees. The FAA will continue to support the ongoing
harmonization effort toward the overtemperature test rule with the JAA
through the ARAC. However, the proposed overtemperature test
requirements in the SNPRM for 30-second and 2-minute OEI ratings are
published as an addition to the existing rule based on the comments
received. It is anticipated that the ARAC will recommend the adoption
of the overtemperature test for these new ratings in their draft
proposals.
Section 33.90 Initial Maintenance Inspection
One commenter suggests that the interpretation of the current
Sec. 33.90 needs to clearly define the requirements in that section for
engines that incorporate the new OEI rated power levels, and that an
advisory circular must be published together with this Final rule.
The FAA disagrees. The FAA should not delay publication of this
Final rule pending the development of new advisory material. The FAA
plans to issue to the advisory material as soon as practical.
Section 33.93 Teardown Inspection
One commenter states that in proposed Sec. 33.93, there is an
``and'' which they believe should be an ``or'' in the first sentence of
proposed Sec. 33.93(c), so that the fifth and sixth lines would read:
``the endurance testing of Sec. 33.87 (b) or (c) or (d) or (e) or this
part and followed * * *''. This change is needed because proposed
33.87(a) states: ``for engines tested under paragraphs (b), (c), (d) or
(e) of this section * * *'' and the new Sec. 33.87(f) reads: ``and
following completion of the tests under paragraphs (b), (c), (d) or (e)
of this section * * *''.
The FAA agrees. The changes to revised Sec. 33.93 are made.
Regulatory Evaluation Summary
Changes to the federal regulations must undergo several economic
analyses. First, Executive Order 12866 directs Federal agencies to
promulgate new regulations or modify existing regulations only if the
potential benefits to society outweigh the potential costs. Second, the
Regulatory Flexibility Act of 1980 requires agencies to analyze the
economic impact of regulatory changes on small entities. Finally, the
Office of Management and Budget directs agencies to assess the effects
of regulatory changes on international trade. In conducting these
assessments, the FAA has determined that this rule: (1) Will generate
benefits exceeding its costs and is not ``significant'' as defined in
Executive Order 12866; (2) is not ``significant'' as defined in DOT's
Policies and Procedures; (3) will not have a significant impact on a
substantial number of small entities; and (4) will not restrain
international trade. These analyses are available in the docket.
The new OEI power ratings will afford rotorcraft manufacturers the
opportunity to install higher rated engines in their products. The
principal operational benefits will be the ability to carry higher
payloads from existing fields or to takeoff from smaller fields with
current payloads, which should enable more Category B operators to use
their rotorcraft for Category A operations, and also increase the
potential for all operators to use more efficient and profitable
routes.
The testing costs associated with obtaining these ratings should be
viewed as the price of an additional capability and would be evaluated
by the manufacturer based on market potential. It is not possible to
quantify the extent of the net operational benefits that will be
realized by the operators because the number of products that will be
certificated to this standard cannot be predicted. The FAA is able to
conclude, however, that the rule will not have a negative economic
impact on manufacturers or operators. Because these are optional
ratings, manufacturers will provide this capability only if the
additional costs can be recovered in the marketplace.
Safety after an engine failure under the provisions of this rule
will be as test equivalent to operational safety under the previous
regulations. This assessment is based on the requirement for an engine
inspection following one mission cycle of either the 30-second or 2-
minute OEI power levels. All engine parts that may not be suitable for
further use must be discarded and replaced in order to maintain the
continued airworthiness of the engine. The existing minimum level of
engine airworthiness will be maintained under this rule by virtue of
new and existing design, analysis, and test certification requirements.
In summary, the FAA finds that the benefits of this rule will exceed
the costs.
International Trade Impact Analysis
These rule changes will have little or no impact on trade for both
U.S. firms doing business in foreign countries and foreign firms doing
business in the United States. In the U.S. market, foreign
manufacturers will have the option of designing engines and helicopters
capable of satisfying the new OEI ratings and therefore will not be at
a competitive disadvantage with U.S. manufacturers. Because of the
large U.S. market, foreign manufacturers are likely to certify their
rotorcraft to U.S. rules, which will limit any competitive advantage
U.S. manufacturers might gain in foreign markets.
Regulatory Flexibility Determination
The Regulatory Flexibility Act of 1980 (RFA) was enacted by
Congress to ensure that small entities are not unnecessarily or
disproportionately burdened by Government regulations. The RFA requires
a Regulatory Flexibility Analysis if a rule would have a significant
economic impact, either detrimental or beneficial, 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. A review of domestic engine manufacturers indicates
that none meets the minimum size threshold. As such, the FAA has
determined that this rule will not have significant economic impact on
a substantial number of small entities.
Federalism Implications
The regulations 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
[[Page 31328]]
responsibilities among the various levels of government. Therefore, in
accordance with Executive Order 12612, it is determined that this
regulation does not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
Conclusion
For the reasons discussed in the preamble, and based on the
findings in the Regulatory Flexibility Determination and the
International Trade Impact Analysis, the FAA has determined that this
regulation is not a significant regulatory action under Executive Order
12866. In addition, the FAA certifies that these amendments do not have
a significant economic impact, positive or negative, on a substantial
number of small entities under the criteria of the Regulatory
Flexibility Act. These amendments are considered nonsignificant under
DOT Regulatory Policies and Procedures (44 FR 11034, February 26,
1979). A regulatory evaluation of the amendments, including a
Regulatory Flexibility Determination and Trade Impact Analysis, has
been placed in the docket. A copy may be obtained by contacting the
person identified under FOR FURTHER INFORMATION CONTACT.
List of Subjects
14 CFR Part 1
Airmen, Flights, Balloons, Parachutes, Aircraft Pilots, Pilots
Transportation, Agreements, Kites, Air Safety, Safety, Aviation Safety,
Air Transportation, Air Carriers, Aircraft, Airports, Airplanes,
Helicopters, Rotorcraft, Heliports, Engines, Ratings.
14 CFR Part 33
Engines, Rotorcraft, Air Transportation, Aircraft, Aviation safety,
Safety.
Adoption of the Amendments
Accordingly, The Federal Aviation Administration (FAA) amends 14
CFR part 1 and part 33 as follows:
PART 1--DEFINITIONS AND ABBREVIATIONS
1. The authority citation for part 1 continues to read as follows:
Authority: 49 U.S.C 106(g), 40113, 44701.
2. Section 1.1 is amended by adding the definitions in alphabetical
order of ``Rated 30-Second OEI Power'' and ``Rated 2-Minute OEI Power''
to read as follows:
Sec. 1.1 General Definitions.
* * * * *
Rated 30-second OEI power, with respect to rotorcraft turbine
engines, means the approved brake horsepower developed under static
conditions at specified altitudes and temperatures within the operating
limitations established for the engine under part 33 of this chapter,
for continued one-flight operation after the failure of one engine in
multiengine rotorcraft, limited to three periods of use no longer than
30 seconds each in any one flight, and followed by mandatory inspection
and prescribed maintenance action.
Rated 2-minute OEI power, with respect to rotorcraft turbine
engines, means the approved brake horsepower developed under static
conditions at specified altitudes and temperatures within the operating
limitations established for the engine under part 33 of this chapter,
for continued one-flight operation after the failure of one engine in
multiengine rotorcraft, limited to three periods of use no longer than
2 minutes each in any one flight, and followed by mandatory inspection
and prescribed maintenance action.
* * * * *
PART 33--AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES
3. The authority citation for part 33 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
4. Section 33.7 is amended by redesignating paragraph (c)(1)(viii)
as (c)(1)(x); by revising newly redesignated (c)(1)(x); and by adding
new paragraphs (c)(1)(viii) and (c)(1)(ix) to read as follows:
Sec. 33.7 Engine ratings and operating limitations.
* * * * *
(c) * * *
(1) * * *
(viii) Rated 2-minute OEI power;
(ix) Rated 30-second OEI power; and
(x) Auxiliary power unit (APU) mode of operation.
* * * * *
5. Section 33.29 is amended by adding new paragraph (c) as follows:
Sec. 33.29 Instrument connection.
* * * * *
(c) Each rotorcraft turbine engine having a 30-second OEI rating
and a 2-minute OEI rating must have a provision for a means to:
(1) Alert the pilot when the engine is at the 30-second OEI and the
2-minute OEI power levels, when the event begins, and when the time
interval expires;
(2) Determine, in a positive manner, that the engine has been
operated at each rating; and
(3) Automatically record each usage and duration of power at each
rating.
6. Section 33.67 is amended by adding new paragraph (d) as follows:
Sec. 33.67 Fuel system.
* * * * *
(d) Engines having a 30-second OEI rating must incorporate means
for automatic availability and automatic control of a 30-second OEI
power.
7. Section 33.85 is amended by adding new paragraphs (c) and (d) as
follows:
Sec. 33.85 Calibration tests.
* * * * *
(c) In showing compliance with this section, each condition must
stabilize before measurements are taken, except as permitted by
paragraph (d) of this section.
(d) In the case of engines having 30-second OEI, and 2-minute OEI
ratings, measurements taken during the applicable endurance test
prescribed in Sec. 33.87(f) (1) through (8) may be used in showing
compliance with the requirements of this section for these OEI ratings.
8. Section 33.87 is amended by revising the introductory text of
paragraph (a) and paragraph (a)(8); by redesignating paragraph (f) as
paragraph (g); by revising the reference ``(e)(2) (ii) through (iv)''
to read ``(g)(2) (ii) through (iv)'' in newly designated paragraph
(g)(2)(i), by revising the reference ``(e)(2)(i)'' to read
``(g)(2)(i)'' in newly designated paragraph ``(g)(2)(ii)''; by revising
the reference ``(e)(2)(i)'' to read ``(g)(2)(i)'' in newly designated
paragraph ``(g)(2)(iii)''; by revising the reference ``(e)(2) (i) and
(ii)'' to read ``(g)(2) (i) and (ii)'' in newly designated paragraph
(g)(2)(iv); and by adding a new paragraph (f) to read as follows:
Sec. 33.87 Endurance test.
(a) General. Each engine must be subjected to an endurance test
that includes a total of at least 150 hours of operation and, depending
upon the type and contemplated use of the engine, consists of one of
the series of runs specified in paragraphs (b) through (g) of this
section, as applicable. For engines tested under paragraphs (b), (c),
(d), (e) or (g) of this section, the prescribed 6-hour test sequence
must be conducted 25 times to complete the required 150 hours of
operation. Engines for which the 30-second OEI and 2-minute OEI ratings
are desired must be further tested under paragraph
[[Page 31329]]
(f) of this section. The following test requirements apply:
* * * * *
(8) If the number of occurrences of either transient rotor shaft
overspeed or transient gas overtemperature is limited, that number of
the accelerations required by paragraphs (b) through (g) of this
section must be made at the limiting overspeed or overtemperature. If
the number of occurrences is not limited, half the required
accelerations must be made at the limiting overspeed or
overtemperature.
* * * * *
(f) Rotorcraft engines for which 30-second OEI and 2-minute OEI
ratings are desired. For each rotorcraft engine for which 30-second OEI
and 2-minute OEI power ratings are desired, and following completion of
the tests under paragraphs (b), (c), (d), or (e) of this section, the
applicant may disassemble the tested engine to the extent necessary to
show compliance with the requirements of Sec. 33.93(a). The tested
engine must then be reassembled using the same parts used during the
test runs of paragraphs (b), (c), (d), or (e) of this section, except
those parts described as consumables in the Instructions for Continued
Airworthiness. The applicant must then conduct the following test
sequence four times, for a total time of not less than 120 minutes:
(1) Takeoff power. Three minutes at rated takeoff power.
(2)30-second OEI power. Thirty seconds at rated 30-second OEI
power.
(3) 2-minute OEI power. Two minutes at rated 2-minute OEI power.
(4) 30-minute OEI power, continuous OEI power, or maximum
continuous power. Five minutes at rated 30-minute OEI power, rated
continuous OEI power, or rated maximum continuous power, whichever is
greatest, except that, during the first test sequence, this period
shall be 65 minutes.
(5) 50 percent takeoff power. One minute at 50 percent takeoff
power.
(6) 30-second OEI power. Thirty seconds at rated 30-second OEI
power.
(7) 2-minute OEI power. Two minutes at rated 2-minute OEI power.
(8) Idle. One minute at idle.
* * * * *
9. Section 33.88 is revised to read as follows:
Sec. 33.88 Engine overtemperature test.
(a) Each engine must run for 5 minutes at maximum permissible rpm
with the gas temperature at least 75 deg.F (42 deg.C) higher than the
maximum rating's steady-state operating limit, excluding maximum values
of rpm and gas temperature associated with the 30-second OEI and 2-
minute OEI ratings. Following this run, the turbine assembly must be
within serviceable limits.
(b) Each engine for which 30-second OEI and 2-minute OEI ratings
are desired, that does not incorporate a means to limit temperature,
must be run for a period of 5 minutes at the maximum power-on rpm with
the gas temperature at least 75 deg.F (42 deg.C) higher than the 30-
second OEI rating operating limit. Following this run, the turbine
assembly may exhibit distress beyond the limits for an overtemperature
condition provided the engine is shown by analysis or test, as found
necessary by the Administrator, to maintain the integrity of the
turbine assembly.
(c) Each engine for which 30-second OEI and 2-minute OEI ratings
are desired, that incorporates a means to limit temperature, must be
run for a period of 4 minutes at the maximum power-on rpm with the gas
temperature at least 35 deg.F (20 deg.C) higher than the maximum
operating limit. Following this run, the turbine assembly may exhibit
distress beyond the limits for an overtemperature condition provided
the engine is shown by analysis or test, as found necessary by the
Administrator, to maintain the integrity of the turbine assembly.
(d) A separate test vehicle may be used for each test condition.
10. Section 33.93 is revised to read as follows:
Sec. 33.93 Teardown inspection.
(a) After completing the endurance testing of Sec. 33.87 (b), (c),
(d), (e), or (g) of this part, each engine must be completely
disassembled, and
(1) Each component having an adjustment setting and a functioning
characteristic that can be established independent of installation on
the engine must retain each setting and functioning characteristic
within the limits that were established and recorded at the beginning
of the test; and
(2) Each engine part must conform to the type design and be
eligible for incorporation into an engine for continued operation, in
accordance with information submitted in compliance with Sec. 33.4.
(b) After completing the endurance testing of Sec. 33.87(f), each
engine must be completely disassembled, and
(1) Each component having an adjustment setting and a functioning
characteristic that can be established independent of installation on
the engine must retain each setting and functioning characteristic
within the limits that were established and recorded at the beginning
of the test; and
(2) Each engine may exhibit deterioration in excess of that
permitted in paragraph (a)(2) of this section including some engine
parts or components that may be unsuitable for further use. The
applicant must show by analysis and/or test, as found necessary by the
Administrator, that structural integrity of the engine including
mounts, cases, bearing supports, shafts, and rotors, is maintained; or
(c) In lieu of compliance with paragraph (b) of this section, each
engine for which the 30-second OEI and 2-minute OEI ratings are
desired, may be subjected to the endurance testing of Secs. 33.87 (b),
(c), (d), or (e) of this part, and followed by the testing of
Sec. 33.87(f) without intervening disassembly and inspection. However,
the engine must comply with paragraph (a) of this section after
completing the endurance testing of Sec. 33.87(f).
Issued in Washington, DC, on May 30, 1996.
David R. Hinson,
Administrator.
[FR Doc. 96-14083 Filed 6-18-96; 8:45 am]
BILLING CODE 4910-13-M
