Filtered Flight Data, 7345-7357 [2010-3321]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 75, Number 33 (Friday, February 19, 2010)]
[Rules and Regulations]
[Pages 7345-7357]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-3321]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 121, 125, and 135

[Docket No. FAA-2006-26135; Amendment Nos. 121-347, 125-59, and 135-
120]
RIN 2120-AI79


Filtered Flight Data

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA amends digital flight data recorder regulations 
affecting certain air carriers and operators. This final rule prohibits 
the filtering of some original flight recorder sensor signals unless a 
certificate holder can show that the data can be accurately 
reconstructed. This final rule improves the integrity and quality of 
the data recorded on digital flight data recorders while giving 
aircraft designers and operators more flexibility in system design and 
operation where allowable.

DATES: These amendments become effective April 20, 2010.

FOR FURTHER INFORMATION CONTACT: For technical questions concerning 
this final rule contact Brian A. Verna, Avionics Systems Branch, 
Aircraft Certification Service, AIR-130, Federal Aviation 
Administration, 800 Independence Avenue, SW., Washington, DC 20591;

[[Page 7346]]

telephone (202) 385-4643; fax (202) 385-4651; e-mail 
brian.verna@faa.gov. For legal questions concerning this final 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 
karen.petronis@faa.gov.

SUPPLEMENTARY INFORMATION: 

Authority for This Rulemaking

    The FAA's authority to issue aviation safety rules is found in 
Title 49 of the United States Code. Subtitle I, Section 106 describes 
the authority of the FAA Administrator. Subtitle VII, Aviation 
Programs, describes in more detail the scope of the agency's authority.
    This rulemaking is promulgated under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701. Under that section, 
the FAA is charged with prescribing regulations providing minimum 
standards for other practices, methods and procedures necessary for 
safety in air commerce. This regulation is within the scope of that 
authority since flight data recorders are the only means available to 
account for aircraft movement and flight crew actions critical to 
finding the probable cause of incidents or accidents, including data 
that could prevent future incidents or accidents.

I. Background

A. Statement of the Problem

    During several aircraft accident investigations, the National 
Transportation Safety Board (NTSB) found that some flight data recorder 
systems were filtering flight recorder sensor signals before they were 
recorded. As a result, the recorded data did not accurately reflect the 
aircraft's performance or the movements of the flight control systems 
before and during the accident or incident under investigation. Such 
signal filtering both hampered and delayed the investigations. 
Throughout the investigation of American Airlines Flight 587 (Flight 
587), which crashed after takeoff from John F. Kennedy Airport, 
Jamaica, New York in November 2001, the NTSB expended significant time 
and resources trying to recreate the performance and movements of the 
flight controls of the accident aircraft.
    In November 2003, the NTSB issued three recommendations (NTSB 
Recommendations A-03-48/A-03-49/A-03-50, November 6, 2003) on digital 
flight data recorder (DFDR) recording requirements. The NTSB 
recommended that the FAA require all aircraft to have a DFDR system 
installed ``capable of recording values that meet the accuracy 
requirements through the full dynamic range of each parameter at a 
frequency sufficient to determine a complete, accurate, and unambiguous 
time history of parameter activity, with emphasis on capturing each 
parameter's dynamic motion at the maximum rate possible, including 
reversals of direction at the maximum rate possible.''

B. Action by the FAA--Notice of Proposed Rulemaking

    In 2006, the FAA issued a notice that proposed a prohibition on 
filtering certain original flight data sensor signals (November 15, 
2006, 71 FR 66634). The 2006 NPRM contains a complete discussion of the 
proposal and the events leading up to it.
    The comments received in response to the 2006 NPRM alerted the FAA 
to several features of the proposed prohibition that would have had 
significantly more impact than the agency had expected. The issue that 
produced the most comment was the proposed definition of filtering, 
which described filtering as a change to any original sensor signal for 
any reason other than the three specified in the proposal. The comments 
indicated that the level of signal processing that is in use on newer 
flight data systems no longer corresponds to more traditional concepts 
of filtering, and leaves in question whether current system designs 
would be considered to be filtering data before recording.
    As the FAA considered changes to the definition of filtering, the 
agency continued studying what is quickly becoming the standard in 
electronic signal processing. Our intent in the 2006 NPRM was to 
prohibit the processing of certain flight data sensor signals that 
would result in inaccurate data being preserved, as happened with the 
rudder movement data on Flight 587.
    The investigation following the crash of Flight 587 indicated that 
the issue was not that data were filtered, but that the actual rudder 
movement data could not be reconstructed once processed by installed 
filtering devices. While a prohibition like our 2006 proposal would 
solve the problem, current capabilities suggested that when properly 
processed and documented, data can be reconstructed from a system 
design that incorporates filtering.

C. Action by the FAA--Supplemental Notice of Proposed Rulemaking

    The determination that flight recorder systems from which data may 
be reconstructed were acceptable exceeded the scope of the changes in 
the 2006 NPRM. Accordingly, the FAA issued a supplemental notice of 
proposed rulemaking (August 15, 2008, 73 FR 47857)(SNPRM). The SNPRM 
proposed that recording of filtered flight data be allowed if a 
certificate holder could demonstrate that the `filtered' recorded data 
meet the recording requirements of the regulations, and that the 
original sensor signal data could be accurately reconstructed using a 
documented, repeatable process.
    In the SNPRM, the FAA changed its position from a strict filtering 
prohibition to one of conditional allowance that distinguishes between 
two groups of flight recorder parameters. The first group contained 
those that are prohibited from being filtered unless a certificate 
holder can demonstrate that it has done the tests and analyses and 
maintains the procedures necessary to reconstruct the original sensor 
signal values from the filtered recorded data. The second group 
included those parameters whose signals may be filtered without further 
action as long as they meet the requirements of the regulations.
    The option not to filter any or all parameters remained an 
acceptable means of compliance with the regulations. In all cases, the 
accuracy and all other requirements of Appendix M of part 121 (or 
Appendix E of part 125 or Appendix F of part 135) must continue to be 
met. The ability to reconstruct data would not forgive any appendix 
requirement for any parameter.
    The proposed time for compliance in the SNPRM was four years after 
the effective date of the final rule. Within that four-year period, one 
of two things was to happen.
    If an operating certificate holder elected not to filter any of the 
restricted parameters, it had four years to test its DFDR systems, 
verify that none of the restricted parameters are being filtered, or, 
if a restricted parameter is being filtered, modify that parameter to 
eliminate the filtering.
    If a certificate holder chose to filter a restricted parameter and 
show by test and analyses that the originating signal can be 
reconstructed, the procedures for reconstruction would have to be 
submitted to the FAA after the next heavy maintenance check of an 
airplane (beginning six months after the effective date of the final 
rule), but not later than two years after the effective date of the 
final rule. If a certificate holder has several of the same make, model 
and series airplane (group) with the same certificated DFDR system 
installed, the

[[Page 7347]]

procedures need only be submitted once for the entire group of 
airplanes with identically installed systems. The compliance date for a 
group would be tied to the first airplane going in for a heavy 
maintenance check six months after the rule is final. Submission of the 
data to the FAA would be required no later than the time the first 
airplane of a group completes that heavy maintenance check.
    This compliance schedule was intended to allow time for the FAA to 
determine that the submitted reconstruction procedures are repeatable, 
but still allow time for other compliance action (within the four 
years) if repeatability was not accomplished. A certificate holder that 
was unable to show repeatability for any restricted parameter would be 
required to modify the parameter to eliminate filtering before the four 
year compliance period ends.
    We did not include in the rule text a time limit for submission of 
the reconstruction procedures to the NTSB following an accident or 
occurrence that requires the NTSB be notified. We presumed that the 
reconstruction data are included as part of the recorder and its data 
that are subject to Sec.  121.344(i) and the NTSB's authority under 49 
CFR part 830. We invited comment on whether a specific, brief time for 
submission needs to be included separately in the rule for the 
reconstruction procedure data.
    The SNPRM contains a more complete discussion of the proposal.
    Following publication of the SNPRM, industry members contacted the 
FAA indicating that the economic evaluation did not reflect the effect 
of the proposed rule language. The SNPRM stated that a certificate 
holder could not filter data unless the recorded values complied with 
Appendix M and the certificate holder possessed procedures to 
reconstruct original sensor signals. The FAA had intended to propose 
rule language that applies to certain parameters if the recorded values 
do not comply with Appendix M. If Appendix M requirements are not met, 
then the certificate holder would have the choice to either remove the 
filtering or show by test and analysis that the original, unfiltered 
values can be successfully reconstructed to meet the requirements of 
Appendix M. On November 13, 2008, we amended the SNPRM (73 FR 67115) by 
publishing a correction and extension of the comment period until 
December 29, 2008.

II. Discussion of Comments to the SNPRM

A. General Summary

    The FAA received eight comments covering more than 30 issues in 
response to the SNPRM. The NTSB generally agreed with the proposed rule 
and urged adoption of a final rule. Airbus, Boeing Commercial Airplanes 
(Boeing), the Regional Airlines Association (RAA) and Astar Air Cargo, 
Inc. (Astar) agreed on the importance of recording unfiltered, accurate 
data, but did not agree with the SNPRM's approach to accomplish this 
goal. The General Aviation Manufacturers Association (GAMA) agreed with 
the rule as proposed and provided supplemental cost information. Two 
individual commenters expressed support for the rule as proposed.

B. Parameters Covered by the Filtering Prohibition

    In the SNPRM, the FAA used the commenters' term ``no filter list'' 
to describe those parameters prohibited from being filtered. While not 
entirely accurate, the FAA continues to use ``no filter list'' when 
discussing these comments to prevent further confusion.
    The SNPRM proposed the same ``no filter list'' as the 2006 NPRM 
with the addition of 14 parameters requested by the NTSB in its 2006 
comment. The FAA included these additional parameters in proposed Sec.  
121.346(b)(1) because the NTSB stated that they would provide valuable 
data during accident investigation and should not be filtered.
    Airbus and Boeing asked that the FAA remove all parameters from the 
``no filter list'' except parameters 12-17 and 88 based on the 
complexity of current filtering techniques and the cost burden to 
industry associated with FDR system modifications. They cited specific 
cases where aircraft systems (such as an air data computer and an air 
data inertial reference unit) process data from multiple sources to be 
transmitted through an ARINC 429 data bus, and to be used by other 
aircraft systems, including the DFDR. Airbus identified parameters 2, 
3, 4, 6, 7, 9, 26, 32, 42, 43, and 70 as coming from these multiple 
source systems. Boeing provided general information that supported the 
Airbus comment, and noted that significant cost and effort would be 
required to revise multiple aircraft systems to comply with the 
proposed rule. Airbus also raised the modification cost issue, although 
it did not provide any supporting cost data for the 11 parameters it 
suggested be removed from the proposed list. Boeing noted that it was 
not aware of any investigation that had been adversely affected by 
filtered data from the parameters it suggested be excluded, and thus 
could find no safety benefit that would balance the cost of the system 
revision.
    Boeing provided specific information supporting its request to 
remove the parameters for heading (number 4) and engine thrust (number 
9) from the ``no filter list.'' Boeing noted that the Appendix M 
requirements for these two parameters indicate that the recorded values 
are to come from the primary flight crew reference. These data are 
smoothed for readability when displayed to the flight crew. Their being 
filtered is required in the appendices to parts 121, 125, and 135, and 
thus should not be included in the ``no filter'' list.
    Boeing and Airbus stated that the acceleration outputs, parameters 
5, 8, and 18, should not be included in the ``no filter list.'' They 
argued that ARINC Characteristic 717 ``Flight Data Recording and 
Recording Systems'' specifies that accelerometer outputs be filtered in 
order to provide accurate and readable data to the DFDR. They stated 
that removing the ARINC-specified filtering would result in erroneous 
acceleration data due to aircraft vibration.
    The FAA agrees with Boeing and Airbus that the parameters covered 
by the prohibition should be limited to flight control surface 
positions, flight control input positions and flight control input 
forces. Since parameters 1 through 4, 6, 7, 9, 26, 32, 43, 68, 70, and 
77 are non-flight control parameters and are slower-changing parameters 
sampled at less than 4 Hertz (Hz), they are not negatively affected by 
filtering. Additionally, the FAA agrees with Boeing and Airbus 
regarding parameters 5, 8, and 18. Although these are more quickly 
changing parameters, without the filtering specified by ARINC 717, the 
accelerometers would provide unreadable data. The FAA has determined 
that there is no safety benefit in requiring reconstruction of the 
original sensor signal values for these parameters, and that the impact 
on industry would have been significantly greater than the FAA 
anticipated when they were proposed for inclusion.
    The FAA has not changed its position on parameter 42 (throttle 
lever angle). Although it is only required to be sampled at 1 Hz, 
parameter 42 is a critical flight control input position parameter and 
remains subject to the filtering restriction.
    Accordingly, the final rule does not restrict the filtering of the 
non-flight control parameters as discussed above.

[[Page 7348]]

Further, the FAA agrees with Boeing regarding the recording of primary 
flight crew reference for parameters 4 and 9, and the two parameters 
are not included in the filtering prohibition in the final rule.

C. Filtered Flight Data Signal Definition

    In the SNPRM, the FAA proposed that a flight data recorder signal 
is considered filtered when an original sensor signal is changed in any 
way, other than changes necessary to:
    (1) Accomplish analog to digital conversion of the signal,
    (2) Format a digital signal into a DFDR compatible format; or
    (3) Eliminate a high frequency component of a signal that is 
outside the operational bandwidth of the sensor.
    Boeing requested an expansion of this definition that would allow 
the averaging of two or more data samples acquired at the same point in 
time from different sensors, which would provide the best available 
representation of that parameter.
    Boeing and Airbus each recommended changes to the term ``original 
sensor signal.'' Airbus recommended replacing it with the term ``signal 
output from the original sensor system.'' Boeing recommended defining a 
sensor as a device that perceives deviations from a reference and 
converts them into signals or information that can be used by systems 
on the airplane. Boeing added that a sensor can be a system that 
accepts information from multiple points of measurement and processes 
this information into data useable by other airplane systems.
    While the FAA disagrees with Boeing's request to expand the 
definition of a filtered flight data signal, the agency agrees with 
Boeing and Airbus that the concept of what constitutes an original 
sensor signal can be expanded within the regulatory definition. To 
address these concerns, material from the commenters will be 
incorporated as examples in FAA Advisory Circular 20-141B 
``Airworthiness and Operational Approval of Digital Flight Data 
Recorder Systems.''
    The FAA agrees with Boeing and Airbus that an original sensor 
signal can come from either a single sensor or a system that accepts 
multiple sensor inputs to provide accurate information to other 
aircraft systems. For example, the FAA does not consider it necessary 
to record every ring laser gyroscope input into the electronic flight 
instrument system, nor to directly record the output of an unfiltered 
accelerometer. The signal conditioning and filtering techniques used to 
record parameters 2, 3, 4, 6, 7, 9, 26, 32, 43, and 70 are necessary to 
provide accurate data for several aircraft systems, only one of which 
is the flight recorder system. The redesigning of aircraft critical 
systems or the significant alteration of current instruments from which 
data are gathered was not the intent of the proposed rule, and would be 
outside the scope of this rulemaking.

D. Reconstruction of Filtered Data

    Shortly after the close of the comment period for the 2006 NPRM, 
the FAA learned of technological developments that would allow the 
reconstruction of data that had been filtered before they were 
recorded. The FAA determined that this option should be made available 
to operators rather than the simple prohibition proposed in the 2006 
NPRM. That decision led to the publication of the SNPRM in 2008, which 
proposed to allow filtering if data could be reconstructed, and 
requested comment on several issues related to the ability to 
reconstruct.
    Boeing commented that, with regard to parameters that are sampled 
at one second or slower, reconstruction would be both ``unrealistic and 
problematic'' and suggested that the option of reconstruction not be 
included in the final rule. Boeing noted that for some parameters, the 
data are conditioned at the microsecond level. When sampled at once per 
second, the conditioned inputs are nonexistent and not subject to 
reconstruction.
    The FAA understands Boeing's concern and agrees that, under the 
circumstances stated, the data would not be available for 
reconstruction. The agency presumes from Boeing's comment that its 
position is based on the assumption that the conditioned data would be 
considered filtered under the FAA's proposed definition, making it both 
subject to the prohibition yet impossible to reconstruct. However, from 
the examples presented to the FAA by Boeing, the type of conditioning 
taking place would not be considered filtering under the proposed 
definition, and thus not subject to the prohibition or the 
reconstruction option. The option to reconstruct filtered data remains 
in this final rule. The reconstruction of filtered flight data has been 
proven to be effective for rapidly changing parameters (sampled at four 
or more times per second).
    Astar noted that the requirement to maintain DFDR data appears in 
Sec.  121.344(i), while the filtering requirement is being moved to new 
Sec.  121.346. Astar commented that the separation of the requirements 
makes the proposed language (including the phrase ``of this section'') 
inaccurate.
    The FAA agrees. The new Sec.  121.346(c)(2)(ii) references Sec.  
121.344(i) as a requirement for reconstruction documentation.
    The GAMA requested that the FAA provide further guidance regarding 
the type of documentation an operator must possess to demonstrate 
compliance with the proposed regulation. The GAMA noted that part 135 
operators generally do not operate large fleets of similar airplanes, 
and thus a simple approach to documentation is needed.
    The FAA agrees on the need for simple compliance documentation. As 
discussed in more detail below, each operator will be responsible for 
creating a record for each of its airplanes indicating its compliance 
status with this rule, including a reference to any parameters being 
filtered. The FAA anticipates that much of this analysis will be 
available from the original equipment manufacturers. A record of each 
airplane's status regarding filtering is to be maintained as part of 
the flight data recorder correlation documentation already required. 
Compliance with the requirements for reconstruction data, including 
record maintenance, will be more complex if filtering is found and the 
reconstruction option is chosen. Detailed information regarding the 
content and maintenance of that data will be available in FAA Advisory 
Circular 20-141B ``Airworthiness and Operational Approval of Digital 
Flight Data Recorder Systems.''

E. Appendix M

1. Introductory Text
    In both the 2006 NPRM and 2008 SNPRM, the FAA proposed the 
following language to clarify ``dynamic condition'' as used in the 
introductory text to part 121 Appendix M (and comparable appendices in 
other parts):
    ``Dynamic condition means the parameter is experiencing change at 
the maximum rate available, including the maximum rate of reversal.''
    In its comments on both proposals, the NTSB requested the language 
be revised to state the ``maximum rate possible.'' The NTSB stressed 
the importance of having recording systems capable of accurately 
recording motion rates typically experienced during an accident 
sequence.
    In its comment to the SNPRM, Boeing requested that the language be 
eliminated. Boeing stated that the prohibition in proposed Sec.  
121.346 eliminates the need for the introductory text in the 
appendices. In the alternative, Boeing suggested that the

[[Page 7349]]

introductory text be revised to read: ``[d]ynamic condition means the 
parameter is experiencing change at the maximum rate the source system 
can cause by design, including the maximum rate of reversal.'' Boeing 
interprets dynamic condition to be both fundamental to the design of 
and unique to the function of each aircraft system.
    Airbus requested that the introductory text be revised to read: 
``[d]ynamic condition means the parameter is experiencing change at the 
maximum rate under operational conditions, including maximum rate of 
reversal.'' Airbus was concerned that the proposed language went beyond 
the operational limits of actual systems, and further suggested that 
the language be moved from the appendix to Sec.  121.344.
    The FAA has decided that the introductory text of the appendices 
will refer to the ``maximum rate attainable.'' Following much debate, 
the term attainable appears to satisfy the commenters' concerns, 
including the design limitations of a specific source system.
    In the SNPRM, the FAA noted that the NTSB did not provide any 
rationale for its suggested change to ``maximum rate possible'' and the 
agency could not conclude that it was an improvement. Since the word 
``possible'' could be interpreted to include states that are well 
beyond the operational range of equipment, the suggested change 
appeared inappropriate as a regulatory standard.
    Additional guidance will be included in FAA Advisory Circular 20-
141B ``Airworthiness and Operational Approval of Digital Flight Data 
Recorder Systems.''
    Finally, the FAA does not agree that the introductory text should 
be relocated to Sec.  121.344. The text refers to requirements for each 
parameter as listed in the appendix. Separating it from the appendix 
requirements would cause unnecessary confusion.
2. ``Accuracy (Sensor Input)'' Column in Appendix M
    Boeing stated that the appendix column titled ``Accuracy (Sensor 
input)'' is ambiguous in terms of what constitutes accuracy and how 
accuracy is measured. Boeing submitted its own definition of the term 
``accuracy'' based on its suggested definition of the term ``sensor'' 
(discussed above). Boeing described its understanding of accuracy as 
being the relationship between the actual entity being measured and the 
recorded position of that entity within a stated range.
    Airbus requested that the FAA provide values for the maximum 
dynamic error allowable for each parameter in the appendices. Airbus 
added that the amount of dynamic error is dependent on the sampling 
rate and the operational condition of an individual aircraft.
    The FAA disagrees with adding a definition of accuracy or adding 
maximum dynamic error in the appendices. The accuracy column has been 
present in the regulation since its adoption in 1997 and has not been 
an identified source of confusion. Further, the FAA did not propose any 
changes to accuracy specifications, making these suggested changes 
outside the scope of this rulemaking. Except for the change to the term 
``maximum rate attainable'' in the introductory text, no other changes 
to the appendices are being adopted in this final rule. The FAA will 
expand its discussion of how accuracy is measured in the update to the 
advisory circular material based on material submitted by the 
commenters.
3. Expansion of Appendix M
    Boeing requested that Appendix M include a table defining each 
parameter's primary and secondary purposes, whether or not it should be 
filtered, and from what source it should be recorded.
    The FAA considers an additional table in Appendix M to be 
inappropriate and beyond the scope of this rulemaking. Other than a 
clarification of the language in the introductory text, no changes to 
Appendix M were proposed. Compliance with Appendix M remains unchanged.
    Astar requested that the parameters affected by this rule be 
identified by an additional column in the appendices. Astar also found 
the placement of the filtering prohibition in Sec.  121.346 (rather 
than Sec.  121.344) to be misleading.
    The FAA does not agree with Astar that an additional column in the 
appendices is necessary. The filtering prohibition was moved to a 
separate regulatory section in order to highlight its importance and 
prevent it from being overlooked in the extensive requirements already 
present in Sec.  121.344. No changes have been made based on this 
comment.

F. Applicability

1. Existing and Newly Manufactured Aircraft
    In the SNPRM, we proposed that the filtered flight data prohibition 
apply to both existing and newly manufactured aircraft. Airbus and the 
RAA agreed with the approach to allow filtering if an operator can 
demonstrate accurate, repeatable reconstruction of an original sensor 
signal. However, they stated that any final rule should only apply to 
newly manufactured airplanes or airplanes on which Supplemental Type 
Certificate (STC) changes to the flight recorder system have been 
installed.
    Airbus noted that such application of the rule would be less costly 
since manufacturers would be able to combine new designs into other 
flight recorder system improvements.
    The RAA stated that the safety concerns raised by the FAA are 
issues applicable to the design and certification processes, making the 
solution better suited to be applicable only to newly manufactured 
airplanes.
    As we stated in the 2006 NPRM and the SNPRM, the FAA considered the 
regulatory alternative of limiting the filtering prohibition to newly 
manufactured aircraft. While this approach is always less costly than a 
rule that affects the in-service fleet, it would also fail to address 
the aircraft currently operating with flight recorder systems that 
filter critical flight data before recording it. The FAA is also 
concerned that failing to cover in-service aircraft could lead to more 
filtering, which could result from future system modifications on in-
service aircraft not subject to the prohibition.
    Experience has shown that filtering has caused problems during 
accident investigations. The FAA disagrees that the reconstruction 
efforts during the investigation of Flight 587 had an acceptable 
outcome. The NTSB has not released any formal opinion that the results 
from the Flight 587 data reconstruction were satisfactory, or that the 
processes involved in that data reconstruction were acceptable. The FAA 
recognizes that data reconstruction, when satisfactory from an accuracy 
standpoint and shown to be repeatable, is an acceptable alternative and 
has included it in this final rule. However, the agency cannot conclude 
that the problems uncovered by the Flight 587 investigation have been 
solved. Allowing airplanes to remain in the fleet while filtering 
critical data is not an acceptable alternative. Without this rule, 
there would be no requirement to develop and maintain accurate, 
repeatable processes for reconstructing data that are filtered before 
being recorded.
2. A300/A310 Airplanes
    Airbus stated that on its A300-600 and A310 airplanes, parameters 
15, 16, 17, and 19 are filtered under our proposed definition. Airbus 
noted that the filter conversion algorithms have been solved for the 
A300/A310 airplanes, concluding that the problem

[[Page 7350]]

will not occur again, unless a customer has chosen to change the 
recording system through an STC.
    Astar stated its understanding that the FAA's reference to the A300 
in the SNPRM is to the A300-600 model. Astar added that it operates the 
A300-B4B model airplane and has not identified data filtering during 
its review of research and engineering documentation. Astar requested 
that the final rule include a list of those aircraft that are not 
covered by the rule.
    The RAA stated that there had to be ``a more cost effective way to 
identify the DFDR's of concern without having every certificate holder 
``recertify'' their product.'' The RAA also stated that since ``the FAA 
has the certification data for the DFDR systems for all airplane types 
in operation,'' the agency should be able to determine specific 
aircraft types that ``need not be recertified to the new standards.''
    As discussed above, the FAA finds it unacceptable to limit the 
applicability of this rule as suggested. The FAA does not know the 
identity of all models or the total number of airplanes that may be 
recording filtered data, and thus has no rational basis to restrict 
applicability. The FAA does not possess the engineering documentation 
required to evaluate the DFDR systems of all airplanes currently in 
operation. The requirement for each operator to assess the function of 
its airplanes with regard to filtering is a critical facet of this 
rule. This effort is not a recertification, as suggested. It is first a 
determination of system function. Once that determination is made, and 
if filtering is found, the operator will have the choice of how to 
comply with this rule. The FAA cannot ignore the possibility of an in-
service airplane filtering critical data simply because the model is no 
longer in production. Similarly, limited applicability leaves open the 
possibility of future filtering by modifications made on airplanes that 
were not filtering when the rule took effect. The applicability of this 
final rule is adopted as proposed.
3. Part 91 Airplanes
    The GAMA stated that the proposed regulation would have a 
significant cost and burden impact on the owners and operators of 
aircraft that are equipped with DFDRs as required under Sec.  91.609. 
The GAMA noted that it is typical for an aircraft that operates under 
part 135 to begin and end its operating life cycle under part 91. For 
aircraft equipped with a flight recorder operating under part 91 and 
135, the GAMA estimated that between 1,125 and 5,600 aircraft could be 
affected, resulting in a $2,000,000 to $9,000,000 impact on the general 
aviation community for no measurable benefit.
    Neither the 2006 NPRM nor the SNPRM proposed any changes to part 91 
requirements. The FAA cannot predict and would not have any basis for 
presuming how many or which airplanes might change operating parts, or 
who would be operating them. In addition, the costs of complying with 
this rule would be minimal when compared to the significant differences 
between part 91 and part 135 operating requirements overall. No change 
to the regulations is being made based on this comment.

G. Compliance Time

    The SNPRM included a compliance time from six months to two years 
for an operator to develop, validate, and submit filtered data 
reconstruction procedures to the FAA. The proposed rule included a 
final compliance time of four years for airplanes manufactured up to 18 
months after the effective date of a final rule.
    Astar commented that the compliance time in the 2006 NPRM appears 
to be different from that in the SNPRM, and suggests that the time for 
demonstrating that an airplane's flight data recorder system is not 
filtering data is confusing.
    The FAA understands the commenter's concerns and has reconsidered 
the language of the compliance time paragraph. The final rule includes 
the following compliance requirements.
    Operators will have 18 months from the effective date of this rule 
(referenced in this discussion as the reporting date) to review their 
DFDR systems and create a record that indicates whether the DFDR system 
on each airplane is filtering any of the parameters included in the 
``no filter list.'' If any of those parameters are being filtered, the 
record must also indicate which are affected. If no parameters are 
being filtered, that record entry should be made at the time of the 
determination, and an operator need take no further action unless a 
change is made to a DFDR system. Records of this action are to be 
maintained as part of the flight data recorder correlation 
documentation already required by the regulations.
    Operators that identify filtered parameters will have two options. 
If an operator chooses to remove the filtering, it has four years from 
the effective date (thirty months after the reporting date) to make the 
system modifications. If an operator chooses to demonstrate by tests 
and analyses that filtered data can be reconstructed, the operator has 
up to 18 months from the reporting date to submit its reconstruction 
package to the FAA for approval. This submission date accounts for the 
time needed for the FAA to review the tests and analyses and verify 
their repeatability.
    In all cases, compliance with the rule is required four years from 
the effective date. In no case will the submission of reconstruction 
tests and analyses be considered compliance until that submission is 
approved by the FAA. Operators that choose that method of compliance 
are cautioned to submit their tests and analyses as early as possible 
in case their submissions fail to be approved and other action need be 
taken.
    Operators may submit material from manufacturers for all showings 
required. However, for all `group' submissions (all airplanes of a 
particular model, for example), the operator must indicate in its 
records that the manufacturer's verifications apply to a particular 
airplane's DFDR system and that the airplane's DFDR system has not been 
modified to remove it from the group characteristics with regard to 
data filtering. Entries must be made for individual airplanes, not for 
models as a group. The record must be maintained as part of the flight 
data recorder correlation documentation already required by the 
regulations.
    These compliance times provide ample opportunity for certificate 
holders to make choices about their equipment and conduct any necessary 
analyses during a regularly scheduled heavy maintenance visit, reducing 
potential impact on scheduled operations or additional out-of-service 
time. Much of the initial work in determining whether filtering is 
present on restricted parameters does not require physical access to 
airplane systems, but may be determined by reference to the airplane's 
DFDR system engineering and maintenance documentation.

H. Cost/Benefit Analysis

    In the regulatory evaluation for the 2008 SNPRM, the FAA estimated 
it would cost certificate holders a total of $28,160 to undertake a 
review of DFDR systems documentation to determine whether filtering 
were taking place. The FAA stated that it was unable to estimate any 
further impact of the proposed rule, since we had no data indicating 
the number of airplanes in the fleet that were filtering data, nor how 
much it would cost in any instance to correct. Commenters provided some 
cost information, as discussed below, but none provided data related to 
developing reconstruction procedures.

[[Page 7351]]

1. Airbus A300/A310 Retrofit Costs
    Airbus estimated that, for its A300/A310 fleet, the engineering 
costs to correct the recording of filtered data for parameters 12 
through 17 and 88 would be about $750,000. In addition, equipment to 
make each airplane compliant with the rule would cost between $25,000 
and $40,000 per airplane, for a total of $26 million to $46 million for 
the U.S. Airbus fleet. Airbus indicated that these were costs of this 
proposal.
    The FAA reiterates the findings from the SNPRM that the cost to 
correct the DFDR systems on the Airbus A300/310 to comply with the 
existing Appendix M requirements is not a cost of this rule. Even 
though the 1997 regulations do not specifically prohibit filtering, the 
Flight 587 investigation discovered that the airplane's recorded data 
did not meet the accuracy performance requirements of Appendix M. 
Consequently, the compliance cost estimated by Airbus is the cost of 
complying with Appendix M, which has been in effect since 1997. This 
compliance cost would be incurred whether we had ever proposed a rule 
change regarding filtering because the aircraft did not comply with 
Appendix M. This rule does not change compliance with Appendix M. It 
simply provides an option of how compliance may be met: whether the 
data are recorded unfiltered or are filtered and can be reconstructed.
2. Original Equipment Manufacturer Versus Operator Costs
    Boeing stated that many operators would not be able to determine 
which parameters are filtered. Boeing added that the operators depend 
on the manufacturer to identify conditioned parameters and provide 
reconstruction procedures, if applicable. Boeing requested that the FAA 
account for these costs in the regulatory evaluation.
    The FAA agrees that operating certificate holders would be expected 
to consult with the original manufacturers of their equipment to 
identify which (if any) DFDR parameters are being filtered. The list of 
parameters that must be evaluated is now limited to flight control 
surface positions, flight control input positions, flight control 
forces, and throttle lever position. The effort needed to identify 
whether any of these eight parameters are being filtered under the 
regulatory definition is included in the regulatory evaluation. The 
cost is assessed on the operator.

I. Changes Made Through Operating Rules

    Astar agreed with Air Tran's 2006 comment that it is improper to 
use the operating rules of part 121 to impose technical requirements 
unique to a specific model of aircraft or unique to the design of an 
aircraft system. Astar noted that operators are not typically involved 
with the engineering of aircraft systems, and usually do not install or 
alter components. It considers data filtering to be a function of the 
DFDR system design and not the responsibility of the operators.
    The FAA's position has not changed since responding to AirTran's 
comment in the 2008 SNPRM. The DFDR requirements are part of the 
operating rules. The only effective way to implement changes to in-
service aircraft is through the operating rules, since the 
certification rules generally are not retroactive and do not include 
the specific requirements. This rule makes specific changes to certain 
flight recorder parameters, and those parameters exist as part of the 
regulations in parts 121, 125, and 135. A change made to the 
certification rules would not affect aircraft in service.

J. Miscellaneous Comments

1. DFDR System Review
    Astar noted that the SNPRM stated if a certificate holder elects 
not to filter any of the restricted parameters, it has four years to 
test its DFDR systems and verify that none of the restricted parameters 
are being filtered. Astar stated that Sec.  121.346(c) does not 
indicate that a certificate holder should test the DFDR system to 
confirm whether a parameter is filtered or not. Astar requested that 
the FAA remove the explanation of a DFDR system test when a review of 
engineering and maintenance documentation could be used to identify 
parameters that are filtered.
    The FAA agrees that the SNPRM did not include a requirement for a 
certificate holder to test its DFDR system to confirm whether a 
parameter is filtered. The final rule includes a requirement for 
operators to review their DFDR systems and create a record that 
includes each of its airplanes indicating whether and which parameters 
are being filtered. The system review information may be acquired from 
the equipment manufacturer and a physical system test may not be 
necessary. If filtering is found, the means of compliance with this 
rule is also the choice of the operator.
2. Compliance Decision Diagram
    Airbus submitted a complex decision diagram that illustrates its 
understanding of the proposed rule. Airbus stated that if the FAA did 
not agree with the logic of the diagram, Airbus would be unable to 
provide cost information associated with each parameter.
    The FAA does not agree with the logic that underlies Airbus's 
decision diagram. Moreover, changes adopted in this final rule 
significantly affect Airbus's decision diagram. As will be detailed in 
the FAA's decision diagram in AC 20-141B, there is a straightforward 
approach to evaluating the parameters. First, only those parameters 
listed in Sec.  121.346(c) need be evaluated to determine whether they 
are being filtered under the regulatory definition. Next, the 
certificate holder must determine if the recorded data meet the 
accuracy requirements of Appendix M. If they do not, the certificate 
holder needs to decide whether to attempt data reconstruction, or alter 
the DFDR system to record unfiltered data.

III. Final Rule Language

    The structure of the final rule language differs from the 
proposals. In the proposed rules, we differentiated the group of 
parameters that could be filtered from those that could not. That 
distinction is no longer relevant.
    Using part 121 as the example, Sec.  121.346(a) contains the 
definition of filtering. Paragraph (b) states that any parameter may be 
filtered as long as the recorded value meets all of the requirements of 
Appendix M. Paragraph (c) specifies the eight critical flight control 
parameters discussed, and indicates that if any of those parameters are 
filtered, and because of the filtering does not meet the requirements 
of Appendix M, then the compliance option of reconstruction described 
in (c)(1)-(2) is available. A critical parameter that fails to meet 
Appendix M for some reason other than filtering that can be rectified 
by reconstruction is considered a violation of Appendix M and is not 
allowed under any part of the regulation.
    This means that if any of the critical parameters is being filtered 
but nonetheless meets the requirements of Appendix M, no action is 
required. This is true for all other parameters as well. The only 
parameters not required to meet the Appendix M requirements are the 
eight critical ones, and then only if they can be satisfactorily 
reconstructed as required under paragraph (c) to meet Appendix M 
requirements.

[[Page 7352]]

IV. Regulatory Notice and Analysis

Paperwork Reduction Act

    As required by the Paperwork Reduction Act of 1995 (44 U.S.C. 
3507(d)), the FAA has submitted the information requirements associated 
with this proposal to the Office of Management and Budget for its 
review. According to the 1995 amendments to the Paperwork Reduction Act 
(5 CFR 1320.8(b)(2)(vi)), an agency may not collect or sponsor the 
collection of information, nor may it impose an information collection 
requirement unless it displays a currently valid OMB control number. 
The OMB control number for this information collection will be 
published in the Federal Register, after the Office of Management and 
Budget approves it.

International Compatibility

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to comply with 
International Civil Aviation Organization (ICAO) Standards and 
Recommended Practices to the maximum extent practicable. The FAA has 
determined that there are no ICAO Standards and Recommended Practices 
that correspond to these regulations.

Regulatory Evaluation, Regulatory Flexibility Determination, 
International Trade Impact Assessment, and Unfunded Mandates Assessment

    Changes to Federal regulations must undergo several economic 
analyses. First, Executive Order 12866 directs that each Federal agency 
shall propose or adopt a regulation only upon a reasoned determination 
that the benefits of the intended regulation justify its costs. Second, 
the Regulatory Flexibility Act of 1980 (Pub. L. 96-354) requires 
agencies to analyze the economic impact of regulatory changes on small 
entities. Third, the Trade Agreements Act (Pub. L. 96-39) prohibits 
agencies from setting standards that create unnecessary obstacles to 
the foreign commerce of the United States. In developing U.S. 
standards, the Trade Act requires agencies to consider international 
standards and, where appropriate, that they be the basis of U.S. 
standards. Fourth, the Unfunded Mandates Reform Act of 1995 (Pub. L. 
104-4) requires agencies to prepare a written assessment of the costs, 
benefits, and other effects of proposed or final rules that include a 
Federal mandate likely to result in the expenditure by State, local, or 
Tribal governments, in the aggregate, or by the private sector, of $100 
million or more annually (adjusted for inflation with base year of 
1995). This portion of the preamble contains the FAA's analysis of the 
economic impacts of this rule.
    In conducting these analyses, FAA has determined that this final 
rule: (1) Has benefits that justify its costs, (2) is not an 
economically ``significant regulatory action'' as defined in section 
3(f) of Executive Order 12866, (3) is not ``significant'' as defined in 
DOT's Regulatory Policies and Procedures; (4) will not have a 
significant economic impact on a substantial number of small entities; 
(5) will not create unnecessary obstacles to the foreign commerce of 
the United States; and (6) will not impose an unfunded mandate on 
State, local, or Tribal governments, or on the private sector by 
exceeding the threshold identified above. These analyses are summarized 
as follows.

Total Benefits and Costs of This Rule

    This rule allows certain sensor signals to be filtered only if 
either (1) the recorded data meet the requirements in the appropriate 
appendix, or (2) the certificate holder can show that the original 
sensor signal data can be reconstructed to meet those requirements. The 
final rule cost will be about $310,000, which has a present value of 
about $261,000 using a 7 percent discount rate and a present value of 
about $288,000 using a 3 percent discount rate. The benefits of this 
rule are that certificate holders will have an alternative means of 
compliance with the filtering regulations and that the NTSB will have 
more accurate DFDR data for its accident investigations.

Aviation Industry Affected

    The rule applies to each aircraft operated under part 121, 125, or 
135 that is required to have a DFDR system. These aircraft are operated 
primarily by scheduled air carriers and non-scheduled airplane and 
rotorcraft operators. Aircraft operated under other parts of Title 14 
are not affected.

Assumptions

     Discount rate--7%. Sensitivity analysis was performed at 
3% and 7% discount rates.
     Period of Analysis--2010-2011.
     Burdened labor rate for engineers and maintenance 
foremen--$83.12 per hour.\1\
---------------------------------------------------------------------------

    \1\ GRA, Incorporated, Economic Values for FAA Investment and 
Regulatory Decisions, A Guide, Final Report, September 30, 2008, 
Table 7-1A: 2008 Mean Burdened Hourly Labor Rates of Aeronautical 
Engineers and Aviation Mechanics, p. 7-3.
---------------------------------------------------------------------------

     Rule issued on January 1, 2010.
     Costs are based on 2008 dollars.
     Manufacturers complete DFDR system analysis during 2010.
     Certificate holders report DFDR system information in each 
aircraft's correlation documentation during 2011.

Changes From the 2006 NPRM to the Final Rule

    The 2006 NPRM had proposed to prohibit filtering certain original 
flight data sensor signals, which may have required certificate holders 
to redesign their DFDR systems to remove filtering. The final rule 
allows certain original flight data sensor signals to be filtered if 
the recorded data meet the accuracy requirements of the applicable 
appendix or, if they do not meet these requirements, that the 
certificate holder can show that the original flight data sensor 
signals can be reconstructed. The reconstruction procedures and test 
results must be submitted to the FAA and be validated to ensure that 
the required accuracy is being met and the process is repeatable.

Benefits of This Rule

    The Flight 587 accident demonstrated the existence of a filtered 
data recording problem. The lack of accurate and complete recorded 
flight data hampered and delayed the accident investigation. The lack 
of data also introduced an element of uncertainty into the 
determination of the accident's cause.
    Since the 2006 NPRM, comments received from the industry and our 
increasing understanding of the developments in data recording 
capability have led the FAA to conclude that data filtering, in and of 
itself, may not necessarily generate misleading or incomplete 
information that would inherently compromise an accident investigation. 
As long as the recorded sensor signal data meet the accuracy 
specifications, whether the data are filtered is not relevant to the 
progress of a subsequent accident investigation. However, as previously 
described, there are eight parameters that are too critical to accident 
investigation to allow them to be filtered freely. These recorded data 
may, if filtered, be misleading or incomplete and prevent a timely and 
thorough accident investigation. This final rule eliminates that 
possibility by requiring that, for those eight parameters, the aircraft 
DFDR system either (1) record unfiltered data, (2) record filtered data 
that meet the required accuracy specifications, or (3) record filtered 
data that can be reconstructed to recover the original unfiltered 
sensor signal values. So long as the applicable appendix requirements 
are met, this rule allows the certificate

[[Page 7353]]

holder to select the lowest cost compliance alternative.
    The primary benefit from this rule remains better, quicker, and 
less expensive accident investigations. Although the public comments 
provided no quantitative information about the possible benefits of 
this improved information, the NTSB believes that these benefits exist 
and the FAA agrees.

Costs of This Rule

    Calculation of the costs of this rule begins with the presumption 
that each affected aircraft's DFDR system already records results that 
comply with the requirements in Appendix B or M of part 121, Appendix D 
or E of part 125, or Appendix F of part 135. These regulations were 
adopted in 1997, with compliance due no later than 2001. If an operator 
finds that it has aircraft that do not comply with the applicable 1997 
appendix requirements, the costs to bring those aircraft into 
compliance would be a cost of the 1997 rule, not this final rule.
    The initial action necessary to comply with this rule is an 
analysis of the aircraft DFDR system to determine whether data are 
being filtered. Most certificate holders do not have the technical 
capabilities to perform an engineering analysis of DFDR systems. 
However, aircraft manufacturers have the capability and the FAA 
anticipates that they will perform these analyses and provide the 
information to the certificate holders. The second action to comply 
with this rule will be for the certificate holder to create a report 
indicating the status of each airplane regarding filtering. That data 
must be maintained as part of the flight data recorder correlation data 
already required by the regulations.
    Industry sources indicated to the FAA that these engineering 
analyses will require minimal time because most of the work was 
completed during the aircraft certification and is already in the 
possession of the manufacturers. For example, GAMA estimated that one 
of its operators would need 10 hours to complete this analysis for one 
of its aircraft models. The FAA determined that the average amount of 
time a manufacturer needs to gather the certification information, 
review it, complete an analysis and produce a service bulletin (or 
equivalent) is 25 hours for one aircraft model. Clearly, some of these 
analyses will take more than 25 hours while others (primarily those for 
more recently-certificated aircraft models) will simply require the 
manufacturer to review the results of these recent certification tests. 
Finally, for operators to comply with the 18-month requirement for 
reporting the DFDR system status to the FAA, the manufacturers will 
need to complete this process during 2010, which is the first year 
after issuing the final rule.
    The FAA determined that there are 40 large transport category 
commercial airplane models affected by this rule. At a cost of $2,078 
for each analysis (25 hours at $83.12 per hour), the total cost will be 
$83,120, which has a present value of $72,600 using a 7 percent 
discount rate, and a present value of $78,349 using a 3 percent 
discount rate.
    There are 11 other jet airplane models certificated for 10 or more 
passengers that are used in part 135 non-scheduled operations. At a 
cost of $2,078 for an analysis, the total cost will be $22,858, which 
has a present value of $19,955 using a 7 percent discount rate, and a 
present value of $21,546 using a 3 percent discount rate.
    There are 16 turboprop airplane models certificated for 10 or more 
passengers that are used in part 135 non-scheduled operations. At a 
cost of $2,078 for each analysis, the total cost will be $33,248, which 
has a present value of $29,040 using a 7 percent discount rate, and a 
present value of $31,339 using a 3 percent discount rate.
    Finally, there are six rotorcraft models certificated for 10 or 
more passengers that are used in part 135 non-scheduled operations. At 
a cost of $2,078 for each analysis, the total cost will be $12,468, 
which has a present value of $10,890 using a 7 percent discount rate 
and a present value of $11,752 using a 3 percent discount rate.
    Thus, as shown in Table 1, the total cost to manufacturers will be 
$151,694, which has a present value of $132,495 using a 7 percent 
discount rate and a present value of $142,986 using a 3 percent 
discount rate.

   Table 1--Total Costs and Present Value Costs for the Manufacturer Analyses of Aircraft by Type of Aircraft
                                                [In 2008 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                Present value     Present value
                     Type of aircraft                          Total cost      (at 7 percent)    (at 3 percent)
----------------------------------------------------------------------------------------------------------------
Airplanes Used in Parts 121 and 125.......................           $83,120           $72,600           $78,349
Jets Used in Part 135.....................................            22,858            19,965            21,546
Turboprops Used in Part 135...............................            33,248            29,040            31,339
Rotorcraft Used in Part 135...............................            12,468            10,890            11,752
                                                           -----------------------------------------------------
    Total.................................................           151,694           132,495           142,986
----------------------------------------------------------------------------------------------------------------

    One issue that arose was the cost to perform these analyses for 
DFDR systems that have been sufficiently modified to require a 
supplemental type certificate. The FAA determined that this issue is 
not significant because such modifications are infrequent and generally 
do not provide any operational advantage.
    However, each certificate holder has the ultimate responsibility to 
ensure that all of its aircraft DFDR systems are recording sensor 
signal data that meet the applicable range, resolution, and accuracy 
specifications. As discussed, although the manufacturer will provide 
its data to the certificate holder, each certificate holder must 
indicate, for each of its aircraft, the compliance status of that 
aircraft, including whether data from the manufacturer applies to 
individual aircraft. Thus, the certificate holder's incremental 
compliance cost is the paperwork cost to record the compliance status 
of its aircraft. The FAA anticipates that this notification will be 
made during the first half of 2011, the second year after the final 
rule is issued.
    The FAA determined that, on average, it will take a certificate 
holder's maintenance foreman 15 minutes for a one-time total cost of 
$20.78 per aircraft to record in an aircraft's correlation 
documentation whether any data are being filtered.
    There were 7,274 airplanes operated under parts 121 and 125 
required to

[[Page 7354]]

have a DFDR system in 2008.\2\ There were 43 jet airplanes, 269 
turboprop airplanes and 37 rotorcraft operating in part 135 unscheduled 
service required to have a DFDR system in 2009.
---------------------------------------------------------------------------

    \2\ FAA Aerospace Forecast Fiscal Years 2009-2025, Tables 20, 
21, and 26, pp. 79, 80, and 85.
---------------------------------------------------------------------------

    On that basis, part 121 and 125 operators will incur recordation 
costs of $151,154, part 135 non-scheduled jet operators will incur 
recordation costs of $894, part 135 non-scheduled turboprop operators 
will incur recordation costs of $5,590, and part 135 non-scheduled 
helicopter operators will incur recordation costs of $769.
    Thus, as shown in Table 2, the total cost to operators will be 
$158,406, which has a present value of $129,306 using a 7 percent 
discount rate, and a present value of $144,964 using a discount rate of 
3 percent.

     Table 2--Total Costs and Present Value Costs for Operators To Report Compliance to the FAA During 2011
                                                [In 2008 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                Present value     Present value
                Type of certificate holder                     Total cost      (at 7 percent)    (at 3 percent)
----------------------------------------------------------------------------------------------------------------
Parts 121 and 125 Operators...............................          $151,154          $123,386          $138,327
Non-Scheduled Jet.........................................               894               729               818
Non-Scheduled Turboprop...................................             5,590             4,563             5,115
Rotorcraft................................................               769               628               704
                                                           -----------------------------------------------------
    Total.................................................           158,406           129,306           144,964
----------------------------------------------------------------------------------------------------------------

    There is a potential compliance cost if a manufacturer informs an 
operator that some of its aircraft DFDR systems are recording filtered 
flight data for any of the eight critical parameters. The final rule 
requires that if an operator is so informed, then the operator must 
evaluate each filtered parameter to ensure that the recorded data meet 
the requirements of the appropriate appendix. The cost of this 
evaluation is a cost of this final rule. Based on an FAA determination 
that such an evaluation will take four labor hours at a cost of $83.12 
an hour to complete, the cost for an operator to complete an evaluation 
for each affected parameter on each affected aircraft will be $332.48.
    No manufacturer reported to the docket whether any of its aircraft 
DFDR systems were recording filtered data for any of these eight 
parameters. As a consequence, the FAA does not know whether there is 
any such filtered data recording, or the number of affected parameters 
or the number of affected aircraft DFDR systems.
    Therefore, the FAA can only estimate that if there are DFDR systems 
recording filtered data, it will cost an operator $332.48 to evaluate 
each affected parameter on each affected aircraft.
    Thus, the FAA calculated that, as shown in Table 3, the total cost 
to comply with this rule is $310,100, which has a present value of 
$261,801 using a 7 percent discount rate, and a present value of 
$287,950 using a discount rate of 3 percent.

              Table 3--Total Costs and Present Value Costs To Report Compliance With the Final Rule
                                                [In 2008 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                Present value     Present value
                      Type of entity                           Total cost      (at 7 percent)    (at 3 percent)
----------------------------------------------------------------------------------------------------------------
Manufacturer..............................................          $151,694          $132,495          $142,986
Operator..................................................           158,406           129,306           144,964
                                                           -----------------------------------------------------
    Total..............................