X98-10512. Noise Standards: Aircraft Type and Airworthiness Certification

[Federal Register Volume 63, Number 91 (Tuesday, May 12, 1998)]
[Rules and Regulations]
[Page 26063]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: X98-10512]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 36


Noise Standards: Aircraft Type and Airworthiness Certification

CFR Correction

    In Title 14 of the Code of Federal Regulations, parts 1 to 59, 
revised as of January 1, 1998, on page 779, in appendix A to part 36, 
the following text was removed and should be reinstated below each 
equation.

Appendix A to Part 36 [Corrected]

    1. In the first column, in paragraph (d)(1)(i), the omitted text 
should read as follow:
* * * * *
where SPLi and SPLic are the measured and corrected sound pressure 
levels, respectively, in the i-th one-third octave band. The first 
correction term accounts for the effects of change in atmospheric 
sound absorption where i and io are the sound 
absorption coefficients for the test (determined under section 
A36.9(d)) and reference atmospheric conditions, respectively, for 
the i-th one-third octave band and KQ is the measured takeoff sound 
propagation path. The second correction term accounts for the 
effects of atmospheric sound absorption on the change in the sound 
propagation path length where KQc is the corrected takeoff sound 
propagation path. The third correction term accounts for the effects 
of the inverse square law on the change in the sound propagation 
path length.
* * * * *
    2. Also, in the first column, in paragraph (d)(2)(i), the omitted 
text should read as follows:
* * * * *
where NS and NSr are the measured and reference approach sound 
propagation paths, respectively.
* * * * *
    3. In the second column, in paragraph (d)(3), the omitted text 
should read as follows:
* * * * *
where LX is the measured sideline sound propagation path from 
station L (Figure A1) to position X of the aircraft for which PNLTM 
is observed at station L and LXc is the corrected sideline sound 
propagation path.
* * * * *

BILLING CODE 1505-01-D