[Federal Register Volume 73, Number 220 (Thursday, November 13, 2008)]
[Proposed Rules]
[Pages 67115-67117]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-26856]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 121, 125 and 135

[Docket No. FAA-2006-26135; Notice No. 08-08]
RIN 2120-AI79


Filtered Flight Data; Technical Correction and Extension of 
Comment Period

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM); correction 
and extension of comment period.

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SUMMARY: The FAA is correcting an SNPRM published in the Federal 
Register on August 15, 2008, regarding filtered flight data. Questions 
from industry caused us to conclude that the intent expressed in the 
preamble is inconsistent with the proposed rule language. This document 
will clarify our intent and the rule language. We are also extending 
the comment period to allow for consideration of this clarification by 
all interested parties.

DATES: The comment period will close December 29, 2008.

FOR FURTHER INFORMATION CONTACT: For technical questions concerning 
this proposed rule contact Brian A. Verna, Avionics Systems Branch, 
Aircraft Certification Service, AIR-130, Federal Aviation 
Administration, 800 Independence Avenue, SW., Washington, DC 20591; 
telephone (202) 385-4643; fax (202) 385-4651; e-mail 
[email protected]. For legal questions concerning this proposed rule 
contact Karen L. Petronis, Senior Attorney for Regulations, Regulations 
Division, Office of the Chief Counsel, AGC-200, Federal Aviation 
Administration, 800 Independence Avenue, SW., Washington, DC 20591; 
telephone (202) 267-3073; fax 202-267-7971; e-mail 
[email protected].

Background

    Following the publication of a supplemental notice of proposed 
rulemaking on filtered flight data (SNPRM; 73 FR 47857, August 15, 
2008), the FAA was contacted by members of the industry seeking 
clarification of our intent and the scope of specific provisions. A 
summary of that meeting has been placed in the docket for this rule.
    Issues raised at the meeting caused us to realize that the intent 
of the rule as stated in the preamble is inconsistent with the proposed 
rule text. We are restating the intent here and providing revised 
proposed rule text.
    While this preamble discussion uses part 121 as its reference, it 
also applies to parts 125 and 135 and their comparable sections. During 
our review, we also discovered that the SNPRM change to a separate 
section (proposed Sec.  121.346) caused us to inadvertently omit an 
applicability reference for airplanes covered under Sec.  121.344a. We 
have added that reference as part of this correction.
    The definition of filtering, proposed Sec.  121.346(a), remains as 
it was in the SNPRM. Comments should address that section of the 
proposed rule as published in the SNPRM.
    Proposed Sec.  121.346(b) now states that any parameter required to 
be recorded may be filtered as long as the recorded signal value 
continues to meet the requirements of Appendix M.
    Paragraph (c) contains a list of parameters that we consider 
critical from the standpoint of accuracy and accident investigation 
when complying with the required accuracy under the expanded definition 
of dynamic conditions in Appendix M. This list has not changed from the 
SNPRM. If any parameter in the paragraph (c) list is being filtered, 
and the filtered, recorded data do not meet Appendix M, then the 
certificate holder must choose one of the following courses of action:
     Remove the filtering; or
     Demonstrate by test and analysis that the original sensor 
signal value can be reconstructed from the recorded filtered data. If 
an operator attempts to show by test and analysis that the data can be 
reconstructed but the tests and analyses fail, or the results cannot be 
repeated, the filtering must be removed.
    The restructured language of the rule text has obviated the need 
for the second list of parameters. They are

[[Page 67116]]

already covered by paragraph (b); they may be filtered as long as the 
recorded signal value meets Appendix M. We presume that these 
parameters are already in compliance with Appendix M since that 
compliance is required by the 1997 rule changes.
    The compliance paragraph has been redesignated as (d), and has been 
changed to include the correct paragraph references; compliance time 
remains unchanged.
    All other provisions of the proposed rule, including the definition 
of filtering, remain as proposed in the SNPRM published on August 15, 
2008. Because of the confusion generated by the SNPRM language 
published in August, we are extending the comment period for the rule 
as corrected until December 29, 2008.

Correction

PART 121--OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL 
OPERATIONS

    1. On page 47867, in the first column, remove proposed Sec.  
121.346(b) and (c) and add in their place corrected paragraphs (b), (c) 
and (d) to read as follows:


Sec.  121.346  Flight recorders--filtered data.

* * * * *
    (b) An original sensor signal for any flight recorder parameter 
required to be recorded under Sec.  121.344 of this part may be 
filtered only if the recorded signal value continues to meet the 
requirements of Appendix B or M of this part, as applicable.
    (c) For a parameter described in Sec.  121.344(a)(1) through (7), 
(9), (11) through (18), (26), (32), (42), (43), (68), (70), (77), or 
(88), or the corresponding parameter in Appendix B of this part, if the 
recorded signal value is filtered and does not meet the requirements of 
Appendix B or M of this part, as applicable, the certificate holder 
must:
    (1) Remove the filtering and ensure that the recorded signal value 
meets the requirements of Appendix B or M of this part; or
    (2) Demonstrate by test and analysis that the original sensor 
signal value can be reconstructed from the recorded data. This 
demonstration requires that:
    (i) The FAA determine that the procedure submitted by the 
certificate holder as its compliance with paragraph (c)(2) of this 
section is repeatable; and
    (ii) The certificate holder maintain documentation of the procedure 
required to reconstruct the original sensor signal value.
    (d) Compliance. After (four years from effective date), no aircraft 
flight data recording system may filter any parameter listed in 
paragraph (c) of this section that does not meet the requirements of 
Appendix M or B of this part unless the certificate holder possesses 
test and analysis procedures that have been approved by the FAA. The 
procedures must be submitted to the FAA no later than the completion of 
the next heavy maintenance check after [six months after effective 
date] but not later than [two years after the effective date].
    2. On page 48767 in the second column, add amendatory instruction 
2a to amend section 121.344a(e) to read as follows:
    2a. Amend Sec.  121.344a by revising paragraph (e) to read as 
follows:


Sec.  121.344a  Digital flight data recorders for 10-19 seat airplanes.

     * * *
    (e) All airplanes subject to this section are also subject to the 
requirements and exceptions stated in Sec. Sec.  121.344(g) through (k) 
and 121.346 of this part.
* * * * *

PART 125--CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING 
CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD CAPACITY OF 
6,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH 
AIRCRAFT

    3. On page 47867, in the second column, remove proposed Sec.  
125.228(b) and (c) and add in their place corrected paragraphs (b), (c) 
and (d) to read as follows:


Sec.  125.228  Flight recorders--filtered data.

* * * * *
    (b) An original sensor signal for any flight recorder parameter 
required to be recorded under Sec.  125.226 of this part may be 
filtered only if the recorded signal value continues to meet the 
requirements of Appendix D or E of this part, as applicable.
    (c) For a parameter described in Sec.  125.226 (a)(1) through (7), 
(9), (11) through (18), (26), (32), (42), (43), (68), (70), (77), or 
(88), or the corresponding parameter in Appendix D of this part if the 
recorded signal value is filtered and does not meet the requirements of 
Appendix D or E of this part, as applicable, the certificate holder 
must:
    (1) Remove the filtering and ensure that the recorded signal value 
meets the requirements of Appendix D or E of this part; or
    (2) Demonstrate by test and analysis that the original sensor 
signal value can be reconstructed from the recorded data. This 
demonstration requires that:
    (i) The FAA determine that the procedure submitted by the 
certificate holder as its compliance with paragraph (c)(2) of this 
section is repeatable; and
    (ii) The certificate holder maintain documentation of the procedure 
required to reconstruct the original sensor signal value.
    (d) Compliance. After (four years from effective date), no aircraft 
flight data recording system may filter any parameter listed in 
paragraph (c) of this section that does not meet the requirements of 
Appendix D or E of this part unless the certificate holder possesses 
test and analysis procedures that have been approved by the FAA. The 
procedures must be submitted to the FAA no later than the completion of 
the next heavy maintenance check after [six months after effective 
date] but not later than [two years after the effective date].

PART 135--OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS 
AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT

    4. On page 47868, in the first column, remove proposed Sec.  
135.156(b) and (c) and add in their place corrected paragraphs (b), (c) 
and (d) to read as follows:


Sec.  135.156  Flight recorders--filtered data.

* * * * *
    (b) An original sensor signal for any flight recorder parameter 
required to be recorded under Sec.  135.152 of this part may be 
filtered only if the recorded signal value continues to meet the 
requirements of Appendix F of this part, as applicable.
    (c) For a parameter described in Sec.  135.152(h)(1) through (7), 
(9), (11) through (18), (26), (32), (42), (43), (68), (70), (77), or 
(88), if the recorded signal value is filtered and does not meet the 
requirements of Appendix F of this part, as applicable, the certificate 
holder must:
    (1) Remove the filtering and ensure that the recorded signal value 
meets the requirements of Appendix F of this part; or
    (2) Demonstrate by test and analysis that the original sensor 
signal value can be reconstructed from the recorded data. This 
demonstration requires that:
    (i) The FAA determine that the procedure submitted by the 
certificate holder as its compliance with paragraph (c)(2) of this 
section is repeatable; and
    (ii) The certificate holder maintain documentation of the procedure 
required to reconstruct the original sensor signal value.

[[Page 67117]]

    (d) Compliance. After (four years from effective date), no aircraft 
flight data recording system may filter any parameter listed in 
paragraph (c) of this section that does not meet the requirements of 
Appendix F of this part unless the certificate holder possesses test 
and analysis procedures that have been approved by the FAA. The 
procedures must be submitted to the FAA no later than the completion of 
the next heavy maintenance check after [six months after effective 
date] but not later than [two years after the effective date].

    Issued in Washington, DC, on November 6, 2008.
Pamela Hamilton-Powell,
Director, Office of Rulemaking.
[FR Doc. E8-26856 Filed 11-12-08; 8:45 am]
BILLING CODE 4910-13-P