Revised Standards for Cargo or Baggage Compartments in Transport Category Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM); withdrawal and disposition of comments.

SUMMARY:

The FAA is withdrawing a portion of Notice of Proposed Rulemaking No. 97-10 which proposed to upgrade fire safety standards for cargo or baggage compartments in certain transport category aircraft and remove Class D compartments as an alternative for future type certification. The FAA published a final rule that adopted the NPRM's proposed amendments to parts 25 and 121, but requested further comments on the issues relating to part 135. We are withdrawing the part 135 proposal based on the existing safety record and the cost/benefit analysis revised in the light of comments received.

FOR FURTHER INFORMATION CONTACT:

Gary Davis, Flight Standards Service, Federal Aviation Administration, 800 Independence Avenue, SW., Washington, DC 20591; telephone 202-497-4857.

SUPPLEMENTARY INFORMATION:

Background

Between 1946 and 1958, the FAA created five categories of baggage or cargo compartments, assigned letters A through E. In recent years there have been a number of fires in the baggage or cargo compartments of transport category airplanes, especially in Class D compartments. Both Class C and Class D compartments are airtight compartments with protective liners. Unlike Class C compartments, Class D compartments do not have fire detection or suppression capabilities. On some occasions, fires in these compartments have caused accidents and loss of life. In May 1996, a fire that originated in a Class D compartment of a McDonnell Douglas DC-9 operated by Valujet Airlines caused the aircraft to crash. As a result, 110 passengers and crewmembers lost their lives.

Class D compartments have a higher risk of an unknown fire developing and burning out of control because they have no detection or suppression capability and are inaccessible in flight. Class D compartments are larger than the other categories of baggage or cargo compartment. The quantity of oxygen available within the compartment due to its size allows a fire to spread to the point of breaking the protective liner and allowing outside air to enter the compartment.

To address Class D compartment issues, the FAA established successively more restrictive standards for Class C and D compartments (51 FR 18236, May 16, 1986 and 54 FR 7384, February 17, 1989). The increase in fires in Class D compartments caused the FAA to further amend portions of 14 CFR parts 25 and 121 by requiring Class D compartments to meet the fire detection and suppression standards for Class C compartments (63 FR 8032, February 17, 1998).

Notice of Proposed Rulemaking No. 97-10 (63 FR 32412, June 13, 1997) proposed amendments to parts 25, 121, and 135 of title 14 of the Code of Federal Regulations that would have eliminated Class D compartments or converted them to Class C compartments by requiring detection and suppression capability. The final rule adopted only those amendments affecting parts 25 and 121. In response to Notice No. 97-10, several commenters recommended that the FAA exclude airplanes operated under part 135 from the proposed rulemaking because of the anticipated high cost of implementation. Based on comments received to the notice, the FAA deferred the proposed amendment to part 135 pending receipt of additional information. The 1998 final rule requested responses to 13 questions related to the impact of the rulemaking on part 135 operators. The comment period closed on June 17, 1998.

Discussion of Comments

The FAA received eight comments on the final rule. Generally, most of these comments are critical of the FAA's action. Some commenters suggest changes to the final rule. Others mention safety issues, such as the size of the compartments and the amount of ventilation in cargo or baggage compartments. Additional issues addressed include inadequacy of the regulatory flexibility analysis and the length of the compliance period.

Compartment Size

The primary aim of the final rule was to prevent future fires in the baggage or cargo compartments of airplanes. The FAA noted that the size of compartments, particularly Class D compartments, was a vital factor in the spreading of fires throughout airplanes. Although the FAA originally placed limits on the size of Class D compartments, the subsequent widespread transportation of flammable aerosols in cargo compartments led to this final rule eliminating Class D compartments and converting current Class D compartments to Class C compartments by requiring detection and suppression capability.

Two commenters, including the National Air Transportation Association (NATA), discuss various aspects of compartment size. One commenter suggests that Class D compartments should be kept, but only with certain modifications. One suggests placing a more stringent limit on the size of Class D compartments compared to the limits formerly imposed by the FAA. Specifically, a maximum size of 200 cubic feet is suggested, while the former limit placed by the FAA was 1,000 cubic feet. NATA asserts that previous actions made by the FAA demonstrate that fires in cargo or baggage compartments correlate with the compartment's size. They state that transport airplane manufacturers generally limit the size of Class D compartments to only 200 cubic feet, and executive airplanes normally have a size of twenty to forty cubic feet. They assert that on-demand passenger carriers maintain closer control of the contents of baggage in Class D compartments.

FAA Response: The FAA does not fully concur with NATA's assertion that on-demand passenger carriers maintain closer control of the contents of baggage placed in their Class D compartments, since that would entail inspecting each passenger's baggage before flight. It does, however, acknowledge that on-demand operators tend to have better control of the contents of their baggage compartments than scheduled operators due to their closer working relationship with their customers. The FAA concurs that it would be unlikely that on-demand operators would transport other types of cargo other than baggage, and that it is less likely that Class D compartments in on-demand operators' airplanes would contain other types of cargo that could cause a fire to start. As stated by NATA, the FAA has no record of an uncontrolled fire occurring in a Class D compartment in an airplane designed for business use.

Necessity for Rule

NATA states that a precedent exists to exclude part 135 airplanes. They cite a 1991 amendment, Amendment 135-31, which allowed Class D compartments only if they were less than 200 cubic feet. They note that most airplanes with compartments of over 200 cubic feet would be complying under part 121. Thus, the final rule becomes repetitive and unnecessary, according to NATA.

FAA Response: The FAA agrees that many airplanes would already be complying under part 121. Some larger airplanes with 30 or fewer passenger seats may still be used for on-demand service under part 135. The primary effect would be on “business jets” or “commuter category” airplanes used in on-demand passenger carrying and all-cargo operations. As stated previously, the FAA recognizes that the Class D compartments in these airplanes are much smaller and the risk of additional flammable material being carried in these compartments is not as great.

Regulatory Flexibility Analysis

NATA states that the FAA's regulatory flexibility analysis indicates the final rule is expected to impact only a few operators in a negligible manner. NATA contends that FAA's analysis is incomplete and insufficient. The FAA estimates that there will be only 35 unscheduled operators that will be adversely affected by this measure; however, NATA believes that there will be more than 1,500 operators adversely affected by the final rule.

FAA Response: The adoption of the Commuter Rule (Commuter Operations and General Certification and Operations Requirements, 60 FR 65832, December 20, 1995) greatly reduced the scope of operations that may be conducted under the provisions of part 135. The proposed amendments to part 135 would affect few, if any, airplanes used in scheduled service. As stated above, the primary effect would be on “business jets” and commuter category airplanes being used in on-demand passenger carrying and all-cargo operations. NATA's figure is large because they include as examples Learjets, Cessna Citations, and Beechcraft (with a nose or tail baggage area outside the pressure vessel) in their comment.

Our original analysis considered factors related to all three regulatory parts of the proposal—parts 25, 121, and 135. In subsequent analysis on only part 135 factors, we determined that the cost of installation of detection and suppression equipment is not insignificant. There is no record of incident to support the need for the part 135 proposal. Based on the existing safety record and the cost/benefit analysis revised in the light of these comments, the FAA has concluded the cost of requiring part 135 operators to comply with new cargo compartment standards would not result in an increase in safety that would justify the cost. Therefore, the proposed amendment to part 135 would be of substantial cost, and based on the history, would be of marginal benefit.

Compartment Location

One commenter proposes that Class D compartments should be allowed in specific areas of the airplane. He believes that they should be permitted to be located outside of the cabin pressure vessel. Such a measure, along with the installation of a fire detection system, would help avoid the spreading of fires, according to the commenter. Such compartments would be relatively small, have carefully controlled ventilation, and be located outside the cabin pressure vessel.

FAA Response: In regards to future certification of transport category airplanes with Class D compartments, the FAA does not agree that such compartments would provide an acceptable level of safety. Such compartments would still be inaccessible in flight, and lacking in fire suppression capability; and therefore, with only detection capability, Class D compartments would not be as safe as other compartments.

Conclusion

Based on the existing safety record and the cost/benefit analysis revised in the light of these comments, the FAA has concluded the cost of requiring part 135 operators to comply with new cargo compartment standards would not result in an increase in safety that would justify the cost. The FAA has determined that no further rulemaking action is appropriate, and is not adopting the amendment to part 135 proposed in Notice No. 97-10. Therefore, the FAA withdraws the amendment to part 135 proposed in Notice No. 97-10 published June 13, 1997 at 62 FR 32412. The amendments to 14 CFR parts 25 and 121 remain in effect as adopted in the final rule.