CS-E 690 Engine Bleed

(See AMC E 690)

(a)For an Engine having bleed(s) for aircraft and/or Engine uses, the Engine endurance test schedule of CS-E 740 must be varied in accordance with CS-E 690(a) unless the use of the bleed(s) is substantiated by separate test and analysis.

(1)General

(i)Exercise the bleed controls at the end of each stage of the endurance test as per CS-E 740(c)(1), (2) or (3). If the applicant uses an alternate endurance test as per CS-E 740(c)(4), which does not have a prescribed number of test stages, the bleed controls must be exercised 25 times in evenly distributed intervals.

(ii)Complete any other tests which may be necessary to demonstrate the satisfactory functioning of the Engine and the bleeds.

(iii)During the tests of CS-E 690(a)(3), the Engine rotational speed(s) may be reduced if necessary when the bleeds are in operation in order to avoid exceeding the maximum declared jet pipe temperatures. (See CS-E 740(f)(2)).

(2)Calibration Tests. Include a calibration test with each bleed in operation separately and one with all bleeds in operation. (See CS-E 730)

(3)Endurance Test.

(i)If the applicant uses an endurance test as per CS-E 740(c)(1), (2) or (3), run Stages 3, 7, 13, 17 and 23 with the bleed(s) in operation during all the conditions of running for which they are intended to be approved for use. If the applicant uses an alternate endurance test as per CS-E 740(c)(4), which does not have prescribed test stages, the bleed(s) must be in operation for one fifth of the test during all the conditions of running for which they are intended to be approved for use.

(ii)During the four test sequences of CS-E 740(c)(3)(iii), an air bleed extraction need not be used where it is shown that the validity of the test is not compromised.

(b)Contamination Tests of Bleed Air for Cabin Pressurisation or Ventilation. The specifications of this paragraph (b) are applicable where it is desired to declare that compressor bleed air is suitable for direct use in an aircraft cabin pressurisation or ventilation system.

(1)Tests to determine the purity of the air supply must be made.

(2)An analysis of defects which could affect the purity of the bleed air must be prepared and where necessary the defects must be simulated and tests, as agreed by the Agency, must be made to establish the degree of contamination which is likely to occur. If the defect under consideration is such that the Engine would be shut down immediately, the tests required may be modified accordingly.

[Amdt. No.: E/1]