JAR-E 690 Отвеждане на въздуха от двигателя

(See ACJ E 700 for Turbine

Engines for Aeroplanes )

Where any of the operating conditions (e.g. air

or gas pressure, thrust, gas temperature)

substantiated elsewhere in this Sub-Section could

be exceeded in any of the normal and likely

emergency conditions within the flight envelope

declared by the Engine constructor, it shall be

established to the satisfaction of the Authority that

the most severe conditions likely to occur will

have no unacceptable effects on the Engine.

[Ch. 7, 24.1.86]

Там където някои експлоатационни условия (например налягане на въздух или изгорели газове, теглителна сила, температура на газове) обосновани някъде в тoзи раздел, биха могли да се превишат при някои нормални и вероятно опасни състояния в рамките на обявените режими на полета от конструктора на двигателя, трябва да се установи, за удовлетворяване на ГВА, че най-тежкото състояние, което е възможно да се случи няма да има не приемливи въздействия върху двигателя.

(See ACJ E 710)

If continued rotation is prevented by a means

to lock the rotor(s), the Engine must be subjected

to a test that includes 25 locking and unlocking

operations of this means under the following

conditions: the Engine must be shut down from

rated Maximum Continuous thrust/power; the

means for stopping and locking the rotor(s) must

be operated as specified in the Engine operating

instructions while being subjected to the

maximum torque that could result from continued

flight in this condition; and following rotor

locking, the rotor(s) must be held stationary under

these conditions for five minutes for each of the

25 operations.

[Ch. 10, 15.8.99]

Ако има средства предотвратяващи въртенето на роторите на двигателя след спирането им, чрез застопоряване, двигателят трябва да се подложи на изпитание, който включва 25 цикъла на застопоряване и разблокиране на тези средства при следните условия: Двигателят трябва да се изключи при работа на определен негов режим, съответстващ на “Максимално-продължителна теглителна сила/мощност”; средствата за спиране и застопоряване на ротора(те) трябва да работят, както е определено в инструкциите за работа на двигателя, до момента в който се натоварят с максималния въртящ момент, който би могъл да се получи в резултат на продължителен полет в това състояние на двигателя; и последващо застопоряване на ротора(те), ротора(те) трябва да останат в покой ри тези условия за пет минути при всеки един от 25-те цикъла.

(a) Where approval of an Engine is sought

which permits or requires the use of a

continuously-operated ignition system, the

requirements of (b) together with either (c) or (d)

shall be met. (See ACJ E 720(a).)

(b) Separate tests as agreed by the Authority

shall be conducted to show that continuous

ignition systems are safe and effective in the

conditions for which their use is permitted or

required.

(c) The system shall be operated during a

suitable Engine endurance test for periods

representative of the duration and frequency of

operation of the system during likely serv ice

usage, and should be agreed by the Authority for

individual cases. Generally, the schedule shall

include the use of continuous ignition for the

maximum duration which is likely to be achieved

in 1 000 hours of service operation.

(d) It is acceptable to conduct an equivalent

programme by appropriate rig testing, where this

is possible, but in this case final confirmation of

suitability of the equipment in the Engine shall be

obtained by running at least 10 hours (in periods

of at least ½ hour duration) of an Engine

endurance test with the ignition in operation at the

appropiate Engine conditions.

(See ACJ E 730)

(a) The sea-level test bed performance

characteristics of an Engine representative of the

Type Design shall be established by

measurements obtained from a fully stabilised

engine.

(b) In order to identify the Engine Thrust or

Endurance Test, Thrust or Power calibration

curves of the test Engine shall be established at

the beginning and at the end of the Endurance

Test.

(c) The results from (a) and (b) shall form

Engine throughout its entire operating envelope.

[Ch. 9, 21.10.94]

(a) Unless otherwise agreed by the Authority,

the test shall be run in the order prescribed in the

appropriate schedule. On turbo-propeller Engines,

a representative flight propeller shall be fitted.

See JAR–E 890 for Thrust Reverser Tests.

(b) The time taken in changing power and/or

thrust settings during the entire test shall not be

deducted from the prescribed periods at the higher

settings.

(c) Schedules

(1) Schedule for Standard Ratings

(Take-off and Maximum Continuous)

25 six-hour stages, each stage comprising –

Part 1 One hour of alternate 5-minute periods

at Take-off Power or thrust and minimum

ground idle, or, for rotorcraft Engines,

minimum test bed idle (see ACJ E 745).

Part 2 (A) Stages 1 to 15, each of 30

minutes duration, at Maximum Continuous

Power/Thrust.

(B) Stages 16 to 25, each of 30

minutes duration, at Take-off Power/Thrust.

For Engines for Aeroplanes. where Engine

rotational speeds between Maximum Continuous

and Take-off may be used in service, e.g. for

reduced thrust take-off or due to variations with

ambient temperature, and these speeds would not

be adequately covered by other Parts of the

Endurance Test, then the following Part 2 shall be

substituted:

(C) Stages 1 to 10, each of 30

minutes duration at Maximum Continuous

Power/Thrust.

(D) Stages 11 to 15, each of

30 minutes duration at Take-off Power/

Thrust.

(E) Stages 16 to 25, each of

6 approximately equal speed increments

between Maximum Continuous and Take-off

Power/Thrust.

Part 3 One hour and 30 minutes at Maximum

Continuous Power/Thrust.

Part 4 2 hours and 30 minutes covering the

range in 15 approximately equal speed

increments from Ground Idling up to but not

including Maximum Continuous

Power/Thrust.

Part 5 30 minutes of accelerations and

decelerations consisting of 6 cycles from

Ground Idling to Take-off Power/Thrust,

maintaining Take-off Power/Thrust for a

period of 30 seconds, the remaining time

being at Ground Idling.

(2) (i) Schedule for Standard

Ratings with 2½-Minute OEI and/or

Continuous OEI Rating and/or 30-Minute

OEI Rating (when appropriate).

25 six-hour stages, each stage comprising –

Part 1 One hour of alternate 5-minute periods

at Take-off Power or thrust and minimum

ground idle, or, for rotorcraft Engines,

minimum test bed idle (see ACJ E 745),

except that –

(A) In Stages 3 to 20, in place of two

of the 5-minute periods at Take-off

Power/Thrust, run 2½ minutes at Take-off

Power/Thrust followed by 2½ minutes at

2½-Minute OEI Power/Thrust.

(B) In Stages 21 to 25, in place of

three of the 5-minute periods at Take-off

Power/Thrust, run 1 minute at Take-off

Power/Thrust followed by 2 minutes at 2½-Minute

OEI Power/Thrust and 2 minutes at

Take-off Power/Thrust.

Part 2 (A) Stages 1 to 15, each of 30

minutes duration at Maximum Continuous

Power/Thrust.

(B) Stages 16 to 25, each of 30

minutes duration at Take-off Power/Thrust,

except that in one stage a period of 5

minutes in the middle of a 30-minute period

shall be run at 2½-Minute OEI

Power/Thrust.

For Engines for Aeroplanes. Where Engine

rotational speeds between Maximum Continuous

and Take-off may be used in service, e.g. for

reduced thrust take-off or due to variations with

ambient temperature, and these speeds would not

be adequately covered by other Parts of the

Endurance Test, then the following Part 2 shall be

substituted:

(C) Stages 1 to 15, each of 30

minutes duration at Maximum Continuous

Power/Thrust.

(D) Stages 16 to 20, each of 30

minutes duration at Take-off Power/Thrust

except that in Stage 16 a period of 5 minutes

in the middle of the 30-minute period shall

be run at 2½-Minute OEI Power/Thrust.

(E) Stages 21 to 25, each of 30

minutes duration covering the range in six

approximately equal speed increments

between Maximum Continuous and Take-off

Power/Thrust.

Part 3 (A) For Engines for Aeroplanes –

30 minutes at Maximum Continuous

Power/Thrust followed by one hour at

Continuous OEI Power/Thrust.

(B) For Engines for Rotorcraft –

Either (Engines to be approved with

Continuous OEI rating) 30 minutes at

Maximum Continuous Power followed by

one hour at Continuous OEI Power or

(Engines to be approved with 30-Minute

OEI Rating) one hour at Maximum

Continuous Power followed by 30 minutes

at 30-Minute OEI Power. A Continuous OEI

Rating and a 30-Minute OEI Rating at a

higher power level can be cleared in the

same test, if desired, by running 30 minutes

at Maximum Continuous Power followed by

30 minutes at Continuous OEI Power and

then 30 minutes at 30-Minute OEI Power.

Part 4 2 hours and 30 minutes covering the

range in 15 approximately equal increments

from Ground Idling, or, for rotorcraft

Engines, minimum test bed idle, up to but

not including Maximum Continuous Power.

Part 5 30 minutes of accelerations and

decelerations consisting of 6 cycles from

Ground Idling, or, for rotorcraft Engines,

minimum test bed idle, to Take-off

Power/Thrust, maintaining Take-off

Power/Thrust for a period of 30 seconds, the

remaining time being at Ground Idling, or,

for rotorcraft Engines, minimum test bed

idle.

(ii) If only one additional rating is

not required shall be run at the

power/thrust level appropriate to the next

rating down the scale.

(iii) Where a constructor desires

an en-route OEI Rating for 30 minutes

only, then the appropriate FAR 33.87

Schedule may be used in place of this

Schedule. Where this option is taken and

a 2½ Minute OEI Power rating is also

desired, then the appropriate Schedule of

FAR 33.87 must be used.

(d) Accelerations and Decelerations

(1) During scheduled accelerations and

decelerations in Parts 1 and 5,

(i) For aeroplane Engines, the

power or thrust control lever shall be

moved from one extreme position to the

other in a time not greater than one

second.

power demand shall be increased to

Take-off from the minimum test bed idle

(see ACJ E 745) in a time not greater

than one second.

(2) Observations

(i) Turbine Engines for

Aeroplanes.

(A) Readings of power/

thrust, speed and Exhaust Gas

Temperature shall be recorded at

every significant change of Engine

conditions. Following accelerations,

the over-run of speed and

temperature above the steady

conditions at Take-off shall be

noted.

(B) Observations of all

first establishing steady running

conditions and thence, during

periods of continuous steady

running, at approximately 30

minute intervals.

(C) During cyclic or other

running, sufficient observations

shall be made to establish the

power/thrust, speed and temperature

conditions of the Engine whenever

significant readings can be taken.

(ii) Turbine Engines for

Rotorcraft.

Readings of power, rotational

speed, nozzle position and Exhaust Gas

Temperature shall be taken at idling

speed and at the maximum speed

obtained on acceleration. The over run of

speed and temperature above the steady

conditions at Take-off Power shall be

noted. These observations are likely to be

affected by the types of instruments used

and shall therefore be coupled with this

information in the Endurance Test report.

(e) Oil Pressure. The whole of the

Endurance Test shall be run with the oil pressure

set to a value which is within the limits declared

for Engine acceptance, except that –

(1) Stage 22 shall be run with the

pressure set to give that declared as the

minimum for completion of the flight, at

Maximum Continuous conditions, and

(2) One other stage shall be run with

the pressure set to give that declared as the

maximum normal, at maximum continuous

conditions. During this stage the oil

temperature need not be held at its maximum

value. Alternatively, this test may be omitted

from the Endurance Test if appropriate

evidence is available from other testing.

(f) Operating Limitations. The normal

Engine operating limitations of power, rotational

speed, turbine entry temperature, oil temperature,

etc., will be based on the mean values obtained

during the appropriate periods of the Endurance

Test, due allowance having been made for the

limits of accuracy of the instrumentation or

automatic controlling system declared for use in

service and declared in accordance with JAR–E

50 and JAR–E 60.

Similarly, the degrees of compressor and

turbine bleed that may be approved are the

percentages of the mass flow which have been

demonstrated during the Endurance Test.

(1) The characteristics of multispool

Engines may be such that it is not possible to

obtain the maximum rotational speed of each

spool simultaneously at sea-level test bed

conditions, without making the Engine

unacceptably non-standard, or running it in a

non-representative manner. In such

circumstances, the Endurance Test shall be run

at the turbine entry temperatures for which

approval is sought, and evidence from

supplementary endurance testing, to a schedule

acceptable to the Authority, shall be provided

to substantiate the approval of any higher

rotational speed limitations desired. (See ACJ

E 740(f)(1).)

(2) If Stages 3, 7, 13, 17 and 23, with

bleed(s) in operation, require the use of a

rotational speed less than the maximum without

bleed (as permitted by JAR–E 690(a)(1)(iii)),

these Stages need not be included in the

assessment of the mean rotational speed value,

subject to agreement by the Authority.

(3) In the case of Engines incorporating

free power-turbines, if the requisite periods are

not run at the maximum power-turbine torque

for which approval is sought, evidence of

additional running will be required. This may

be obtained from tests equivalent to the

Endurance Test on a similar Engine, the

Endurance Test Engine or the relevant parts of

it. In all such additional running the

appropriate periods shall be run at the

maximum rotational speed for which approval

of the maximum torque is required.

(4) Temperatures

(i) All 2½-Minute OEI, 30-

Minute OEI, Continuous OEI, Take-off

and Maximum Continuous periods of the

test shall be run at the appropriate

maximum declared turbine entry

temperatures unless otherwise agreed.

The means of achieving this (e.g. by

adjustment of the jet pipe nozzle area, the

use of bleed) shall be agreed by the

Authority.

(ii) In general, essentially the

average of the maximum temperatures

achieved during the appropriate periods

of the test will be utilised to establish the

operating limitations of temperature for

the Engine. The average Exhaust Gas

Temperatures will be reduced, however,

by the amounts necessary to ensure that

the turbine entry temperatures in flight do

not exceed the turbine entry temperatures

established by Endurance Test at the

appropriate rating conditions. During the

accelerations and short periods at Take-off

Power, attempts shall be made to run

at maximum temperatures but if, owing to

the unstabilised conditions, lower

temperature readings are recorded, these

need not be included in calculating the

average.

(iii) Engines for Aeroplanes.

Where the Engine characteristics are such

that an acceleration from cold produces a

transient overtemperature in excess of

that for steady state running, a maximum

turbine gas temperature limit for

acceleration with a time limitation of

2 minutes may be approved by running at

the required temperature for the first

2 minutes of each prescribed period at

Take-off Power conditions for 5 minutes

or more, and for the whole of all the

30-second periods at Take-off Power.

Approval for short period transient

conditions at 2½-Minute OEI Power will

not be considered and any temperature

clearance required must be demonstrated

normally during the 2½-Minute OEI

periods of the Endurance Test.

(iv) Engines for Rotorcraft. Where

the Engine characteristics are such that an

acceleration from cold produces a

transient overtemperature in excess of

that for steady state running, a maximum

Exhaust Gas Temperature limit for

acceleration with a time limitation of

2 minutes may be approved by running at

the required temperature for the first

2 minutes of each prescribed period at

Take-off Power conditions in excess of

2 minutes (and for the whole of all the

30-second Take-off Power periods for

Single-Engined Rotorcraft). Approval for

short period transient conditions at 2½-Minute

OEI Power will not be

considered, and any temperature

clearance required must be demonstrated

normally during the Endurance Test.

(v) For all Take-off Power/Thrust

periods of 5 minutes or greater, 5 minutes

shall be run at the maximum oil inlet

temperature declared for the condition,

with the remainder of each 30-minute

period at Take-off Power/Thrust being

run at the normal oil temperature for

take-off. If a 10-minute Take-off

Power/Thrust Rating is sought, then

10 minutes of each 30-minute period at

Take-off Power/Thrust shall be run at the

maximum oil temperature. For all

Maximum Continuous Power/Thrust

periods 30 minutes shall be run at the

maximum oil inlet temperature declared

for the condition, the remainder of each

1½ hour period at Maximum Continuous

Power/Thrust being run at the normal oil

temperature for climb/cruise.

(vi) Where necessary to cater for

short-duration rise of indicated oil

temperature under service conditions

above the maximum established during

the Endurance Test such higher

temperature may be approved as the

Maximum Oil Temperature (with an

appropriate time limitation) without

additional endurance testing, provided

that it can be demonstrated that –

(A) The temperature rise

under service conditions is the

result of a local increase in the oil

temperature at the temperature

sensing position (e.g. as may occur

on reducing power at the top of the

climb when fuel is used as the oil

cooling medium),

(B) There is no significant

increase in the maximum local

temperature of either the Engine

components or the oil in any critical

part of the Engine, and

(C) There is no undue

deterioration of the oil in such

circumstances and no adverse effect

on any system using the oil as a

working fluid (e.g. Propeller

control).

(g) Incremental Periods

(1) If a significant peak blade vibration

is found to exist at any condition within the

operating range of the Engine (not prohibited

under JAR–E 650(d)), not less than 10 hours,

but not exceeding 50%, of the incremental

periods of Part 4 of the Endurance Test shall be

run with the rotational speed varied

continuously over the range for which

vibrations of the largest amplitude were

disclosed by the vibration survey; if there are

other ranges of rotational speed within the

operational range of the Engine where

approximately the same amplitude exists, a

further 10 hours shall be run in the same way

for each such range. The speed variation shall

be effected by automatic means using a method

acceptable to the Authority. (See ACJ E

740(g)(1).)

(2) In the case of Engines operating at

constant speed, the thrust and/or power may be

varied in lieu of speed, in Part 4 of the

endurance test.

(3) In the case of free power-turbine

Engines, the normal operating range of power-turbine

speed shall be covered. This may be

run concurrently with the range of gas

generator speed.

(4) In the case of a free power-turbine

Engine for Rotorcraft, 10 minutes of Part 4 in

each stage of the Endurance Test shall be run at

the Maximum Power-turbine Speed for

Autorotation with the gas generator producing

the most critical conditions associated with this

flight configuration.

[Ch. 7, 24.1.86; Ch. 8, 4.5.90; Ch. 10, 15.8.99]