6.3.9.1 Test cycles used on board shall conform
to the applicable test cycles specified in 3.2.
6.3.9.2 Engine operation on board under a test
cycle specified in 3.2 may not always
be possible, but the test procedure shall, based on the recommendation
of the engine manufacturer and approval by the Administration, be
as close as possible to the procedure defined in 3.2. Therefore, values measured in this
case may not be directly comparable with test-bed results because
measured values are very much dependent on the test cycles.
6.3.9.3 If the number of measuring points on board
is different than those on the test bed, the measuring points and
the weighting factors shall be in accordance with the recommendations
of the applicant for engine certification and approved by the Administration,
taking into account the provisions of 6.4.6.