729
Federal Aviation Administration, DOT
§ 33.87
all other engines, an oil temperature
within the normal operating range.
(4) A turbine entry gas temperature
equal to the maximum steady state
temperature approved for use during
periods longer than 20 seconds when op-
erating at conditions not associated
with 30-second or 2 minutes OEI rat-
ings. The requirement to run the test
at the maximum approved steady state
temperature may be waived by the
FAA if the applicant can demonstrate
that other testing provides substan-
tiation of the temperature effects when
considered in combination with the
other parameters identified in para-
graphs (b)(1), (b)(2) and (b)(3) of this
section.
[Doc. No. 2007–28502, 74 FR 45310, Sept. 2, 2009]
§ 33.85
Calibration tests.
(a) Each engine must be subjected to
those calibration tests necessary to es-
tablish its power characteristics and
the conditions for the endurance test
specified § 33.87. The results of the
power characteristics calibration tests
form the basis for establishing the
characteristics of the engine over its
entire operating range of speeds, pres-
sures, temperatures, and altitudes.
Power ratings are based upon standard
atmospheric conditions with no
airbleed for aircraft services and with
only those accessories installed which
are essential for engine functioning.
(b) A power check at sea level condi-
tions must be accomplished on the en-
durance test engine after the endur-
ance test and any change in power
characteristics which occurs during the
endurance test must be determined.
Measurements taken during the final
portion of the endurance test may be
used in showing compliance with the
requirements of this paragraph.
(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 appli-
cable endurance test prescribed in
§ 33.87(f) (1) through (8) may be used in
showing compliance with the require-
ments of this section for these OEI rat-
ings.
[Doc. No. 3025, 29 FR 7453, June 10, 1964, as
amended by Amdt. 33–6, 39 FR 35468, Oct. 1,
1974; Amdt. 33–18, 61 FR 31328, June 19, 1996]
§ 33.87
Endurance test.
(a)
General. Each engine must be sub-
jected to an endurance test that in-
cludes 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 en-
gines tested under paragraphs (b), (c),
(d), (e) or (g) of this section, the pre-
scribed 6-hour test sequence must be
conducted 25 times to complete the re-
quired 150 hours of operation. Engines
for which the 30-second OEI and 2-
minute OEI ratings are desired must be
further tested under paragraph (f) of
this section. The following test re-
quirements apply:
(1) The runs must be made in the
order found appropriate by the FAA for
the particular engine being tested.
(2) Any automatic engine control
that is part of the engine must control
the engine during the endurance test
except for operations where automatic
control is normally overridden by man-
ual control or where manual control is
otherwise specified for a particular test
run.
(3) Except as provided in paragraph
(a)(5) of this section, power or thrust,
gas temperature, rotor shaft rotational
speed, and, if limited, temperature of
external surfaces of the engine must be
at least 100 percent of the value associ-
ated with the particular engine oper-
ation being tested. More than one test
may be run if all parameters cannot be
held at the 100 percent level simulta-
neously.
(4) The runs must be made using fuel,
lubricants and hydraulic fluid which
conform to the specifications specified
in complying with § 33.7(c).
(5) Maximum air bleed for engine and
aircraft services must be used during
at least one-fifth of the runs, except for
the test required under paragraph (f) of
this section, provided the validity of
the test is not compromised. However,
for these runs, the power or thrust or
the rotor shaft rotational speed may be
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14 CFR Ch. I (1–1–24 Edition)
§ 33.87
less than 100 percent of the value asso-
ciated with the particular operation
being tested if the FAA finds that the
validity of the endurance test is not
compromised.
(6) Each accessory drive and mount-
ing attachment must be loaded in ac-
cordance with paragraphs (a)(6)(i) and
(ii) of this section, except as permitted
by paragraph (a)(6)(iii) of this section
for the test required under paragraph
(f) of this section.
(i) The load imposed by each acces-
sory used only for aircraft service must
be the limit load specified by the appli-
cant for the engine drive and attach-
ment point during rated maximum con-
tinuous power or thrust and higher
output.
(ii) The endurance test of any acces-
sory drive and mounting attachment
under load may be accomplished on a
separate rig if the validity of the test
is confirmed by an approved analysis.
(iii) The applicant is not required to
load the accessory drives and mounting
attachments when running the tests
under paragraphs (f)(1) through (f)(8) of
this section if the applicant can sub-
stantiate that there is no significant
effect on the durability of any acces-
sory drive or engine component. How-
ever, the applicant must add the equiv-
alent engine output power extraction
from the power turbine rotor assembly
to the engine shaft output.
(7) During the runs at any rated
power or thrust the gas temperature
and the oil inlet temperature must be
maintained at the limiting tempera-
ture except where the test periods are
not longer than 5 minutes and do not
allow stabilization. At least one run
must be made with fuel, oil, and hy-
draulic fluid at the minimum pressure
limit and at least one run must be
made with fuel, oil, and hydraulic fluid
at the maximum pressure limit with
fluid temperature reduced as necessary
to allow maximum pressure to be at-
tained.
(8) If the number of occurrences of ei-
ther transient rotor shaft overspeed,
transient gas overtemperature or tran-
sient engine overtorque is limited, that
number of the accelerations required
by paragraphs (b) through (g) of this
section must be made at the limiting
overspeed, overtemperature or over-
torque. If the number of occurrences is
not limited, half the required accelera-
tions must be made at the limiting
overspeed, overtemperature or over-
torque.
(9) For each engine type certificated
for use on supersonic aircraft the fol-
lowing additional test requirements
apply:
(i) To change the thrust setting, the
power control lever must be moved
from the initial position to the final
position in not more than one second
except for movements into the fuel
burning thrust augmentor augmenta-
tion position if additional time to con-
firm ignition is necessary.
(ii) During the runs at any rated aug-
mented thrust the hydraulic fluid tem-
perature must be maintained at the
limiting temperature except where the
test periods are not long enough to
allow stabilization.
(iii) During the simulated supersonic
runs the fuel temperature and induc-
tion air temperature may not be less
than the limiting temperature.
(iv) The endurance test must be con-
ducted with the fuel burning thrust
augmentor installed, with the primary
and secondary exhaust nozzles in-
stalled, and with the variable area ex-
haust nozzles operated during each run
according to the methods specified in
complying with § 33.5(b).
(v) During the runs at thrust settings
for maximum continuous thrust and
percentages thereof, the engine must
be operated with the inlet air distor-
tion at the limit for those thrust set-
tings.
(b)
Engines other than certain rotor-
craft engines. For each engine except a
rotorcraft engine for which a rating is
desired under paragraph (c), (d), or (e)
of this section, the applicant must con-
duct the following runs:
(1)
Takeoff and idling. One hour of al-
ternate five-minute periods at rated
takeoff power or thrust and at idling
power or thrust. The developed powers
or thrusts at takeoff and idling condi-
tions and their corresponding rotor
speed and gas temperature conditions
must be as established by the power
control in accordance with the sched-
ule established by the applicant. The
applicant may, during any one period,
manually control the rotor speed,
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§ 33.87
power, or thrust while taking data to
check performance. For engines with
augmented takeoff power ratings that
involve increases in turbine inlet tem-
perature, rotor speed, or shaft power,
this period of running at takeoff must
be at the augmented rating. For en-
gines with augmented takeoff power
ratings that do not materially increase
operating severity, the amount of run-
ning conducted at the augmented rat-
ing is determined by the FAA. In
changing the power setting after each
period, the power-control lever must be
moved in the manner prescribed in
paragraph (b)(5) of this section.
(2)
Rated maximum continuous and
takeoff power or thrust. Thirty minutes
at—
(i) Rated maximum continuous power
or thrust during fifteen of the twenty-
five 6-hour endurance test cycles; and
(ii) Rated takeoff power or thrust
during ten of the twenty-five 6-hour en-
durance test cycles.
(3)
Rated maximum continuous power or
thrust. One hour and 30 minutes at
rated maximum continuous power or
thrust.
(4)
Incremental cruise power or thrust.
Two hours and 30 minutes at the suc-
cessive power lever positions cor-
responding to at least 15 approximately
equal speed and time increments be-
tween maximum continuous engine ro-
tational speed and ground or minimum
idle rotational speed. For engines oper-
ating at constant speed, the thrust and
power may be varied in place of speed.
If there is significant peak vibration
anywhere between ground idle and
maximum continuous conditions, the
number of increments chosen may be
changed to increase the amount of run-
ning made while subject to the peak vi-
brations up to not more than 50 percent
of the total time spent in incremental
running.
(5)
Acceleration and deceleration runs.
30 minutes of accelerations and decel-
erations, consisting of six cycles from
idling power or thrust to rated takeoff
power or thrust and maintained at the
takeoff power lever position for 30 sec-
onds and at the idling power lever posi-
tion for approximately four and one-
half minutes. In complying with this
paragraph, the power-control lever
must be moved from one extreme posi-
tion to the other in not more than one
second, except that, if different re-
gimes of control operations are incor-
porated necessitating scheduling of the
power-control lever motion in going
from one extreme position to the other,
a longer period of time is acceptable,
but not more than two seconds.
(6)
Starts. One hundred starts must be
made, of which 25 starts must be pre-
ceded by at least a two-hour engine
shutdown. There must be at least 10
false engine starts, pausing for the ap-
plicant’s specified minimum fuel drain-
age time, before attempting a normal
start. There must be at least 10 normal
restarts with not longer than 15 min-
utes since engine shutdown. The re-
maining starts may be made after com-
pleting the 150 hours of endurance test-
ing.
(c)
Rotorcraft engines for which a 30-
minute OEI power rating is desired. For
each rotorcraft engine for which a 30-
minute OEI power rating is desired, the
applicant must conduct the following
series of tests:
(1)
Takeoff and idling. One hour of al-
ternate 5-minute periods at rated take-
off power and at idling power. The de-
veloped powers at takeoff and idling
conditions and their corresponding
rotor speed and gas temperature condi-
tions must be as established by the
power control in accordance with the
schedule established by the applicant.
During any one period, the rotor speed
and power may be controlled manually
while taking data to check perform-
ance. For engines with augmented
takeoff power ratings that involve in-
creases in turbine inlet temperature,
rotor speed, or shaft power, this period
of running at rated takeoff power must
be at the augmented power rating. In
changing the power setting after each
period, the power control lever must be
moved in the manner prescribed in
paragraph (c)(6) of this section.
(2)
Rated maximum continuous and
takeoff power. Thirty minutes at—
(i) Rated maximum continuous power
during fifteen of the twenty-five 6-hour
endurance test cycles; and
(ii) Rated takeoff power during ten of
the twenty-five 6-hour endurance test
cycles.
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14 CFR Ch. I (1–1–24 Edition)
§ 33.87
(3)
Rated maximum continuous power.
One hour at rated maximum contin-
uous power.
(4)
Rated 30-minute OEI power. Thirty
minutes at rated 30-minute OEI power.
(5)
Incremental cruise power. Two
hours and 30 minutes at the successive
power lever positions corresponding
with not less than 15 approximately
equal speed and time increments be-
tween maximum continuous engine ro-
tational speed and ground or minimum
idle rotational speed. For engines oper-
ating at constant speed, power may be
varied in place of speed. If there are
significant peak vibrations anywhere
between ground idle and maximum
continuous conditions, the number of
increments chosen must be changed to
increase the amount of running con-
ducted while subject to peak vibrations
up to not more than 50 percent of the
total time spent in incremental run-
ning.
(6)
Acceleration and deceleration runs.
Thirty minutes of accelerations and de-
celerations, consisting of six cycles
from idling power to rated takeoff
power and maintained at the takeoff
power lever position for 30 seconds and
at the idling power lever position for
approximately 4
1
⁄
2
minutes. In com-
plying with this paragraph, the power
control lever must be moved from one
extreme position to the other in not
more than one second. If, however, dif-
ferent regimes of control operations
are incorporated that necessitate
scheduling of the power control lever
motion from one extreme position to
the other, then a longer period of time
is acceptable, but not more than two
seconds.
(7)
Starts. One hundred starts, of
which 25 starts must be preceded by at
least a two-hour engine shutdown.
There must be at least 10 false engine
starts, pausing for the applicant’s spec-
ified minimum fuel drainage time, be-
fore attempting a normal start. There
must be at least 10 normal restarts not
more than 15 minutes after engine
shutdown. The remaining starts may
be made after completing the 150 hours
of endurance testing.
(d)
Rotorcraft engines for which a con-
tinuous OEI rating is desired. For each
rotorcraft engine for which a contin-
uous OEI power rating is desired, the
applicant must conduct the following
series of tests:
(1)
Takeoff and idling. One hour of al-
ternate 5-minute periods at rated take-
off power and at idling power. The de-
veloped powers at takeoff and idling
conditions and their corresponding
rotor speed and gas temperature condi-
tions must be as established by the
power control in accordance with the
schedule established by the applicant.
During any one period the rotor speed
and power may be controlled manually
while taking data to check perform-
ance. For engines with augmented
takeoff power ratings that involve in-
creases in turbine inlet temperature,
rotor speed, or shaft power, this period
of running at rated takeoff power must
be at the augmented power rating. In
changing the power setting after each
period, the power control lever must be
moved in the manner prescribed in
paragraph (d)(6) of this section.
(2)
Rated maximum continuous and
takeoff power. Thirty minutes at—
(i) Rated maximum continuous power
during fifteen of the twenty-five 6-hour
endurance test cycles; and
(ii) Rated takeoff power during ten of
the twenty-five 6-hour endurance test
cycles.
(3)
Rated continuous OEI power. One
hour at rated continuous OEI power.
(4)
Rated maximum continuous power.
One hour at rated maximum contin-
uous power.
(5)
Incremental cruise power. Two
hours at the successive power lever po-
sitions corresponding with not less
than 12 approximately equal speed and
time increments between maximum
continuous engine rotational speed and
ground or minimum idle rotational
speed. For engines operating at con-
stant speed, power may be varied in
place of speed. If there are significant
peak vibrations anywhere between
ground idle and maximum continuous
conditions, the number of increments
chosen must be changed to increase the
amount of running conducted while
being subjected to the peak vibrations
up to not more than 50 percent of the
total time spent in incremental run-
ning.
(6)
Acceleration and deceleration runs.
Thirty minutes of accelerations and de-
celerations, consisting of six cycles
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§ 33.87
from idling power to rated takeoff
power and maintained at the takeoff
power lever position for 30 seconds and
at the idling power lever position for
approximately 4
1
⁄
2
minutes. In com-
plying with this paragraph, the power
control lever must be moved from one
extreme position to the other in not
more than 1 second, except that if dif-
ferent regimes of control operations
are incorporated necessitating sched-
uling of the power control lever motion
in going from one extreme position to
the other, a longer period of time is ac-
ceptable, but not more than 2 seconds.
(7)
Starts. One hundred starts, of
which 25 starts must be preceded by at
least a 2-hour engine shutdown. There
must be at least 10 false engine starts,
pausing for the applicant’s specified
minimum fuel drainage time, before at-
tempting a normal start. There must
be at least 10 normal restarts with not
longer than 15 minutes since engine
shutdown. The remaining starts may
be made after completing the 150 hours
of endurance testing.
(e)
Rotorcraft engines for which a 2
1
⁄
2
-
minute OEI power rating is desired. For
each rotorcraft engine for which a 2
1
⁄
2
-
minute OEI power rating is desired, the
applicant must conduct the following
series of tests:
(1)
Takeoff, 2
1
⁄
2
-minute OEI, and idling.
One hour of alternate 5-minute periods
at rated takeoff power and at idling
power except that, during the third and
sixth takeoff power periods, only 2
1
⁄
2
minutes need be conducted at rated
takeoff power, and the remaining 2
1
⁄
2
minutes must be conducted at rated
2
1
⁄
2
-minute OEI power. The developed
powers at takeoff, 2
1
⁄
2
-minute OEI, and
idling conditions and their cor-
responding rotor speed and gas tem-
perature conditions must be as estab-
lished by the power control in accord-
ance with the schedule established by
the applicant. The applicant may, dur-
ing any one period, control manually
the rotor speed and power while taking
data to check performance. For engines
with augmented takeoff power ratings
that involve increases in turbine inlet
temperature, rotor speed, or shaft
power, this period of running at rated
takeoff power must be at the aug-
mented rating. In changing the power
setting after or during each period, the
power control lever must be moved in
the manner prescribed in paragraph
(b)(5), (c)(6), or (d)(6) of this section, as
applicable.
(2) The tests required in paragraphs
(b)(2) through (b)(6), or (c)(2) through
(c)(7), or (d)(2) through (d)(7) of this
section, as applicable, except that in
one of the 6-hour test sequences, the
last 5 minutes of the 30 minutes at
takeoff power test period of paragraph
(b)(2) of this section, or of the 30 min-
utes at 30-minute OEI power test pe-
riod of paragraph (c)(4) of this section,
or of the l hour at continuous OEI
power test period of paragraph (d)(3) of
this section, must be run at 2
1
⁄
2
-minute
OEI power.
(f)
Rotorcraft Engines for which 30-sec-
ond OEI and 2-minute OEI ratings are de-
sired. For each rotorcraft engine for
which 30-second OEI and 2-minute OEI
power ratings are desired, and fol-
lowing completion of the tests under
paragraphs (b), (c), (d), or (e) of this
section, the applicant may disassemble
the tested engine to the extent nec-
essary to show compliance with the re-
quirements of § 33.93(a). The tested en-
gine 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 de-
scribed as consumables in the Instruc-
tions for Continued Airworthiness. Ad-
ditionally, the tests required in para-
graphs (f)(1) through (f)(8) of this sec-
tion must be run continuously. If a
stop occurs during these tests, the in-
terrupted sequence must be repeated
unless the applicant shows that the se-
verity of the test would not be reduced
if it were continued. The applicant
must conduct the following test se-
quence 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 sec-
onds 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 whichever is
the greatest of rated 30-minute OEI
power, rated continuous OEI power, or
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§ 33.87
rated maximum continuous power, ex-
cept that, during the first test se-
quence, this period shall be 65 minutes.
However, where the greatest rated
power is 30-minute OEI power, that
sixty-five minute period shall consist
of 30 minutes at 30-minute OEI power
followed by 35 minutes at whichever is
the greater of continuous OEI power or
maximum continuous power.
(5)
50 percent takeoff power. One
minute at 50 percent takeoff power.
(6)
30-second OEI power. Thirty sec-
onds at rated 30-second OEI power.
(7)
2-minute OEI power. Two minutes
at rated 2-minute OEI power.
(8)
Idle. One minute at flight idle.
(g)
Supersonic aircraft engines. For
each engine type certificated for use on
supersonic aircraft the applicant must
conduct the following:
(1)
Subsonic test under sea level ambient
atmospheric conditions. Thirty runs of
one hour each must be made, con-
sisting of—
(i) Two periods of 5 minutes at rated
takeoff augmented thrust each fol-
lowed by 5 minutes at idle thrust;
(ii) One period of 5 minutes at rated
takeoff thrust followed by 5 minutes at
not more than 15 percent of rated take-
off thrust;
(iii) One period of 10 minutes at rated
takeoff augmented thrust followed by 2
minutes at idle thrust, except that if
rated maximum continuous augmented
thrust is lower than rated takeoff aug-
mented thrust, 5 of the 10-minute peri-
ods must be at rated maximum contin-
uous augmented thrust; and
(iv) Six periods of 1 minute at rated
takeoff augmented thrust each fol-
lowed by 2 minutes, including accelera-
tion and deceleration time, at idle
thrust.
(2)
Simulated supersonic test. Each run
of the simulated supersonic test must
be preceded by changing the inlet air
temperature and pressure from that at-
tained at subsonic condition to the
temperature and pressure attained at
supersonic velocity, and must be fol-
lowed by a return to the temperature
attained at subsonic condition. Thirty
runs of 4 hours each must be made,
consisting of—
(i) One period of 30 minutes at the
thrust obtained with the power control
lever set at the position for rated max-
imum continuous augmented thrust
followed by 10 minutes at the thrust
obtained with the power control lever
set at the position for 90 percent of
rated maximum continuous augmented
thrust. The end of this period in the
first five runs must be made with the
induction air temperature at the lim-
iting condition of transient over-
temperature, but need not be repeated
during the periods specified in para-
graphs (g)(2)(ii) through (iv) of this sec-
tion;
(ii) One period repeating the run
specified in paragraph (g)(2)(i) of this
section, except that it must be followed
by 10 minutes at the thrust obtained
with the power control lever set at the
position for 80 percent of rated max-
imum continuous augmented thrust;
(iii) One period repeating the run
specified in paragraph (g)(2)(i) of this
section, except that it must be followed
by 10 minutes at the thrust obtained
with the power control lever set at the
position for 60 percent of rated max-
imum continuous augmented thrust
and then 10 minutes at not more than
15 percent of rated takeoff thrust;
(iv) One period repeating the runs
specified in paragraphs (g)(2)(i) and (ii)
of this section; and
(v) One period of 30 minutes with 25
of the runs made at the thrust obtained
with the power control lever set at the
position for rated maximum contin-
uous augmented thrust, each followed
by idle thrust and with the remaining
5 runs at the thrust obtained with the
power control lever set at the position
for rated maximum continuous aug-
mented thrust for 25 minutes each, fol-
lowed by subsonic operation at not
more than 15 percent or rated takeoff
thrust and accelerated to rated takeoff
thrust for 5 minutes using hot fuel.
(3)
Starts. One hundred starts must be
made, of which 25 starts must be pre-
ceded by an engine shutdown of at
least 2 hours. There must be at least 10
false engine starts, pausing for the ap-
plicant’s specified minimum fuel drain-
age time before attempting a normal
start. At least 10 starts must be normal
restarts, each made no later than 15
minutes after engine shutdown. The
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§ 33.91
starts may be made at any time, in-
cluding the period of endurance test-
ing.
[Doc. No. 3025, 29 FR 7453, June 10, 1964, as
amended by Amdt. 33–3, 32 FR 3737, Mar. 4,
1967; Amdt. 33–6, 39 FR 35468, Oct. 1, 1974;
Amdt. 33–10, 49 FR 6853, Feb. 23, 1984; Amdt.
33–12, 53 FR 34220, Sept. 2, 1988; Amdt. 33–18,
61 FR 31328, June 19, 1996; Amdt. 33–25, 73 FR
48123, Aug. 18, 2008; Amdt. 33–30, 74 FR 45311,
Sept. 2, 2009; Amdt. 33–32, 77 FR 22187, Apr.
13, 2012]
§ 33.88
Engine overtemperature test.
(a) Each engine must run for 5 min-
utes at maximum permissible rpm with
the gas temperature at least 75
°
F (42
°
C) higher than the maximum rating’s
steady-state operating limit, excluding
maximum values of rpm and gas tem-
perature associated with the 30-second
OEI and 2-minute OEI ratings. Fol-
lowing this run, the turbine assembly
must be within serviceable limits.
(b) In addition to the test require-
ments in paragraph (a) of this section,
each engine for which 30-second OEI
and 2-minute OEI ratings are desired,
that incorporates a means for auto-
matic temperature control within its
operating limitations in accordance
with § 33.28(k), must run for a period of
4 minutes at the maximum power-on
rpm with the gas temperature at least
35
°
F (19
°
C) higher than the maximum
operating limit at 30-second OEI rat-
ing. Following this run, the turbine as-
sembly may exhibit distress beyond the
limits for an overtemperature condi-
tion provided the engine is shown by
analysis or test, as found necessary by
the FAA, to maintain the integrity of
the turbine assembly.
(c) A separate test vehicle may be
used for each test condition.
[Doc. No. 26019, 61 FR 31329, June 19, 1996, as
amended by Amdt. 33–25, 73 FR 48124, Aug. 18,
2008; Amdt. 33–26, 73 FR 48285, Aug. 19, 2008]
§ 33.89
Operation test.
(a) The operation test must include
testing found necessary by the Admin-
istrator to demonstrate—
(1) Starting, idling, acceleration,
overspeeding, ignition, functioning of
the propeller (if the engine is des-
ignated to operate with a propeller);
(2) Compliance with the engine re-
sponse requirements of § 33.73; and
(3) The minimum power or thrust re-
sponse time to 95 percent rated takeoff
power or thrust, from power lever posi-
tions representative of minimum idle
and of minimum flight idle, starting
from stabilized idle operation, under
the following engine load conditions:
(i) No bleed air and power extraction
for aircraft use.
(ii) Maximum allowable bleed air and
power extraction for aircraft use.
(iii) An intermediate value for bleed
air and power extraction representa-
tive of that which might be used as a
maximum for aircraft during approach
to a landing.
(4) If testing facilities are not avail-
able, the determination of power ex-
traction required in paragraph (a)(3)(ii)
and (iii) of this section may be accom-
plished through appropriate analytical
means.
(b) The operation test must include
all testing found necessary by the Ad-
ministrator to demonstrate that the
engine has safe operating characteris-
tics throughout its specified operating
envelope.
[Amdt. 33–4, 36 FR 5493, Mar. 24, 1971, as
amended by Amdt. 33–6, 39 FR 35469, Oct. 1,
1974; Amdt. 33–10, 49 FR 6853, Feb. 23, 1984]
§ 33.90
Initial maintenance inspection
test.
Each applicant, except an applicant
for an engine being type certificated
through amendment of an existing type
certificate or through supplemental
type certification procedures, must
complete one of the following tests on
an engine that substantially conforms
to the type design to establish when
the initial maintenance inspection is
required:
(a) An approved engine test that sim-
ulates the conditions in which the en-
gine is expected to operate in service,
including typical start-stop cycles.
(b) An approved engine test con-
ducted in accordance with § 33.201 (c)
through (f).
[Doc. No. FAA–2002–6717, 72 FR 1877, Jan. 16,
2007]
§ 33.91
Engine system and component
tests.
(a) For those systems or components
that cannot be adequately substan-
tiated in accordance with endurance
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