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10 March 2008 FAA
Docket No. FAA-2005-20245
Final Rule, Revisions to Cockpit Voice Recorder (CVR) and Digital Flight Data Recorder (DFDR) Regulations
This 124-page rule mandates upgrades to aircraft cockpit voice and flight data recorders that, according to the FAA, “will enable investigators to retrieve more data from accidents and incidents requiring investigation.”
“Because this is the safest period in aviation history, we now have to be able to analyze each accident in greater detail,” declared FAA acting administrator Robert Sturgell on publication of this final rule. “These enhancements will give us more information about the causes of accidents and find ways to avoid them in the future.”
Under this final rule, which affects manufacturers and operators of airplanes and helicopters with 10 or more passenger seats, all voice recorders must capture the last two hours of cockpit audio instead of the current 15 to 30 minutes. The new rule also requires an independent backup power source for the voice recorders to allow continued recording for 9-11 minutes if all aircraft power sources are lost or interrupted.
Airplanes (but not helicopters) operating under Parts 121, 125 or 135 of FAA regulations (that is, carrying passengers for money on scheduled and unscheduled flights) will have to retrofit some aircraft by March 2012. The rule also mandates these enhancements on all newly built aircraft and helicopters after 7 March 2010.
The new rule mandates that the recorders measure aircraft data more frequently than is now required, including the aircraft’s primary flight control movements and the pilots’ movement of the controls. The data recorders also must retain the last 25 hours of recorded information. These provisions affect new aircraft manufactured after 7 March 2010.
This final rule formalizes current FAA policy that voice and data recorders must be housed in separate units (excluding helicopters) and that no single electrical failure can disable the units. The rule also allows operators who install two combined voice and data recorders to mount one of those combined recorders in the forward part of the aircraft.
Manufacturers have two years to upgrade newly manufactured aircraft to the new standards. Some of the new requirements will have to be retrofitted to the existing fleet (these retrofits were deemed feasible and therefore did not impose an excessive burden on the industry).
The FAA estimates the new rule will cost the industry about $239 million over an 11-year time, from 2007-2017. The rule affects 4,631 existing transport category airplanes, which will require upgraded CVR capability, 259 helicopters that will need RIPS (Recorder Independent Power Supply), and 3,575 business jets for which various upgrades will be required.
The FAA did not put a dollar figure on the benefits to be obtained, stating instead:
“The rule increases the amount and quality of the information being recorded, which may result in new or revised safety rules … or in voluntary changes to airline and pilot procedures that may produce a safer fleet and operations. Although we did not adopt all of the NTSB [National Transportation Safety Board] recommendations concerning CVR and DFDR modifications, we chose the course of action that maximizes safety benefits relative to compliance costs.”
The final rule, issued three years after a proposed rule was published for comment 28 February 2005, falls considerably short of what the NTSB desires. The NTSB had classified last November its “Most Wanted” recorder recommendations as RED, indicating both slowness in implementation and because the FAA response was considered unacceptable. It seems likely that the RED classification will continue.
For example, the NTSB urged retrofit of RIPS onto existing transport category aircraft, in addition to installing RIPS on newly manufactured aircraft. The FAA said retrofit could not be justified:
“As stated, the purpose of the RIPS requirement is to ensure the CVR continues to function for 10 minutes following the loss of its main power source by having its own independent power source. The term ‘independent’ does not describe the location of the RIPS as it relates to the CVR … we state that the RIPS may be a part of the CVR or separate from it.
“Five commenters [including the NTSB] … suggested the final rule should contain a 4-year retrofit RIPS requirement similar to that proposed for the 30-minute-to-2-hour CVR conversion. The NTSB stated the benefits of such a requirement vastly outweigh the additional costs. Boeing agreed, stating that a RIPS retrofit would have significant value for in-service aircraft. …
“While the FAA recognizes the benefits of expanding the RIPS requirement beyond newly manufactured aircraft, we remain unable to mandate retrofit as a cost-beneficial change. When we considered the option for the NPRM, we found that the cost of a RIPS retrofit was considerable and the burden on current operators would be substantial.”
Regarding CVR and DFDR failure from a single electrical source, of which the NTSB was concerned, only newly manufactured aircraft will be wired to assure functioning in the event of a single electrical failure:
“The FAA considered this option [of retrofit] while developing the NPRM and found that a wiring retrofit represents a significant economic burden, and could require extensive aircraft rework in order to rewire not only recorder systems, but other aircraft systems that are affected by changes made for the recorders … The final rule remains applicable only to aircraft manufactured two years after this final rule.”
The NTSB wanted a mandatory requirement for dual CVR/DFDR installation, one placed in the aft of the aircraft and the other well forward, in the nose. The FAA again cited cost, encouraging voluntary but not required installation:
“We did not propose the installation of two full sets of recording equipment, referred to as ‘dual combination recorders,’ as recommended by the NTSB because of the substantial costs involved. We did propose that a RIPS be installed for the CVRs on newly manufactured planes.”
The NTSB is not persuaded by the FAAs logic on costs, saying in its commentary on the NPRM:
“The Board is concerned that the failure to address many of the more significant recorder recommendations at this time will ultimately result in a larger economic obligation for industry and may delay implementation of the associated safety improvements. This is particularly true for the Airbus A380 and Boeing 787, which are in preproduction, making this an ideal opportunity to implement dual combined recorders as well as cockpit image recorders.”
The NTSB wants image recorders to complement CVRs/DFDRs by capturing the instrument panel and pilots’ manipulations of the controls. Also, the NTSB viewed image recorders as a stopgap for airplanes not equipped with CVRs/DFDRs. The NTSB call for video recorders was made in the wake of the 2002 air charter crash of a King Air 100 that killed Sen. Paul Wellstone; the accident aircraft was not required to have flight data or cockpit voice recorders, but a video record of instruments and control motions in the cockpit was seen as a cost-effective solution.
The FAA rejected the notion of requiring the installation of image recorders, although the technology exists to do so. The FAA said:
“The NTSB noted that adding a properly placed cockpit video camera would allow DLCs [Datalink Communications] displayed to the crew to be recorded on the video image recorders. Since the use of video technology would not require any modifications to an aircraft’s communication or display systems, the NTSB stated that this approach to recording DLCs might greatly reduce the time and expense of retrofitting older aircraft.
“Our NPRM did not propose the installation of cockpit video cameras and our regulatory evaluation did not include them in cost estimates or benefits analysis, nor has the use of cockpit video been proposed for public or industry comment. The issue of cockpit video is unsettled and would dramatically delay the implementation of DLC standards that are already being developed internationally. The FAA is not averse to certification of an image recorders system that meets the operational requirements of this rule, but no image recording system will be mandated to comply with DLC recording requirements.”
To this FAA comment, a number of observations are due. First, the NTSB did not propose image recorders solely to capture data link messages displayed on the instrument panel. Rather, that was but one of many benefits foreseen by the NTSB, some others being: to record the presence of smoke in the cockpit (and whether or not the crew donned smoke goggles and oxygen masks), to record switch and toggle positions, to record crew manipulation of throttles and flight controls, and to record key information shown on the primary flight displays (or loss of such displays).
Second, the International Civil Aviation Organization (ICAO) has recommended the use of image recorders.
Third, image recorders would provide a stopgap for those airplanes and helicopters not now required to be equipped with CVRs/DFDRs.
Fourth, the “unsettled” situation averred to by the FAA results in large measure because of its failure to press the issue with industry. The technology to provide image recorders now exists, and in fact the cameras have been successfully tested in both day and night conditions in the cockpit.
The FAA does indicate that data sampling rates will be increased from greater than once per second to once every half or quarter second, thus responding to an NTSB call for more granulated data to measure the sequence of catastrophe in an accident investigation. However, the rule stands silent on the NTSB’s recommendation for additional parameters to capture rudder reversals on B737 aircraft. Uncommanded rudder reversals have caused in-flight upsets and at least two fatal crashes. Although the rudder control system has been modified on B737 aircraft to prevent their recurrence, the FAA has not mandated the additional parameters called for by the NTSB.
On 11 February 2008 the Chairman of the NTSB, Mark Rosenker, wrote FAA Administrator Sturgell expressing dismay regarding the recording of rudder parameters on the 737. This letter is significant for at least two reasons: (1) it shows the difficulty in getting seemingly straightforward recommendations adopted, and (2) stands in sharp contrast to Sturgell’s “happy talk” about the final rule. Rosenker’s letter said, in part:
“The FAA’s final rule was delayed while Boeing and 737 operators dealt with significant changes to the rudder system on these airplanes, which had been mandated by the FAA as a result of the USAir flight 427 accident … On September 5, 2006, the FAA published a supplemental NPRM (SNPRM), ‘Revisions to Digital Flight Data Recorder Regulations for Boeing 737 Airplanes and for Part 125 Operators,’ which requested more current data on the status of the 737 fleet and the anticipated costs of installing the proposed monitoring equipment. The SNPRM also announced that the FAA would not require the recordation of each rudder pedal force (four sensors total) but, rather, would require a single rudder pedal force sensor located ‘midstream’ in the rudder control system. In the SNPRM, the FAA indicated that equipping the 737’s DFDR system to record each rudder pedal would involve significant, costly, and time-consuming alterations to the structure of the 737.
“After the SNPRM comment period closed, Safety Board staff attempted to arrange a meeting with FAA staff to review in detail the extensive modifications that the FAA believed would be associated with a four-transducer system. Board staff did not believe that such a system would involve the cost-prohibitive modifications the FAA believed were necessary for this revision. However, because this issue was the subject of rulemaking, the FAA indicated that it could not discuss these details with the Board.
“For several years, newly manufactured 737s have been equipped with DFDRs that record many, but not all, of the additional parameters recommended. However, these DFDRs record only a single rudder pedal force (four sensors total) identified by the Safety Board as critical to understanding loss-of-control accidents. Because the FAA continues to indicate that it will not take the recommended action 8˝ years after these recommendations were issued … Safety Recommendations A-99-28 and -29 were classified ‘Closed – Unacceptable Action’ at the Board’s November 8, 2007 meeting.”
It would appear that this final rule does advance the state of recorders, mostly for new aircraft, but it does not satisfy about half of the NTSB recommendations. Rather, the rule implements those changes that can be done at modest cost (e.g., less than the cost of one airliner over ten years), but it does not impose the sort of sea-change envisioned by the NTSB.
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