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Safety Recommendation Details

Safety Recommendation A-07-015
Details
Synopsis: On February 16, 2005, about 0913 mountain standard time,1 a Cessna Citation 560, N500AT, operated by Martinair, Inc., for Circuit City Stores, Inc.,2 crashed about 4 nautical miles east of Pueblo Memorial Airport (PUB), Pueblo, Colorado, while on an instrument landing system (ILS) approach to runway 26R. The two pilots and six passengers on board were killed, and the airplane was destroyed by impact forces and postcrash fire. The flight was operating under the provisions of 14 Code of Federal Regulations (CFR) Part 91 on an instrument flight rules flight plan. Instrument meteorological conditions (IMC) prevailed at the time of the accident.
Recommendation: TO THE FEDERAL AVIATION ADMINISTRATION: Require that all pneumatic deice boot-equipped airplanes certified to fly in known icing conditions have a mode incorporated in the deice boot system that will automatically continue to cycle the deice boots once the system has been activated.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Alternate Action
Mode: Aviation
Location: Pueblo, CO, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA05MA037
Accident Reports: Crash During Approach to Landing, Circuit City Stores, Inc., Cessna Citation 560, N500AT
Report #: AAR-07-02
Accident Date: 2/16/2005
Issue Date: 2/27/2007
Date Closed: 10/30/2014
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Alternate Action)
Keyword(s): Icing,

Safety Recommendation History
From: NTSB
To: FAA
Date: 5/12/2016
Response: Correspondence control 201600220, Dated May 12, 2016: The National Transportation Safety Board (NTSB) has reviewed the Federal Aviation Administration’s (FAA) notice of proposed rulemaking (NPRM) titled “Revision of Airworthiness Standards for Normal, Utility, Acrobatic, and Commuter Category Airplanes,” which was published at 81 Federal Register (FR) 13451 on March 14, 2016. The NPRM proposes to amend airworthiness standards for normal, utility, acrobatic, and commuter-category airplanes by removing prescriptive design requirements and replacing them with performance based airworthiness standards. The proposed standards would also replace the current weight and propulsion divisions in small airplane regulations with performance- and risk based divisions for airplanes with a maximum seating capacity of 19 passengers or less and a maximum takeoff weight of 19,000 lbs. or less. In addition, the NPRM proposes to adopt additional airworthiness standards to address certification for flight in icing conditions, enhanced stall characteristics, and minimum control speed to prevent departure from controlled flight for multiengine airplanes. On April 8, 2016, the FAA also published on its website draft Advisory Circular (AC) 23.10 titled “FAA Accepted Means of Compliance Process for 14 [Code of Federal Regulations] CFR Part 23.” The draft AC provides guidance on how to submit a proposed means of compliance (MOC) with Part 23 for acceptance by the Administrator in accordance with proposed section 23.10, “Accepted Means of Compliance,” in the NPRM. This letter provides comments on the NPRM. We will submit separate comments regarding draft AC 23.10. We agree with the FAA’s statement in the NPRM that section 23.1405 addresses Safety Recommendations A-07-14 and-15, which we issued on February 27, 2007: A-07-14 Require manufacturers and operators of pneumatic deice boot-equipped airplanes to revise the guidance contained in their manuals and training programs to emphasize that leading edge deice boots should be activated as soon as the airplane enters icing conditions. [Classified “Closed—Unacceptable Action”] A-07-15 Require that all pneumatic deice boot-equipped airplanes certified to fly in known icing conditions have a mode incorporated in the deice boot system that will automatically continue to cycle the deice boots once the system has been activated. [Classified “Closed—Acceptable Alternate Action”] However, we do not agree that proposed section 23.1405 addresses or is relevant to Safety Recommendation A-10-12, which concerns low-airspeed alerting systems. We believe that proposed section 23.1500, “Flightcrew Interface,” is more appropriate for addressing the safety issue identified in this recommendation, which we issued on February 23, 2010: A-10-12 For all airplanes engaged in commercial operations under 14 [CFR] Parts 121, 135, and 91K, require the installation of low-airspeed alert systems that provide pilots with redundant aural and visual warnings of an impending hazardous low speed condition. [Classified “Open—Acceptable Response”]

From: NTSB
To: FAA
Date: 10/30/2014
Response: We have previously stated that your August 3, 2009, final rule regarding ice protections systems satisfied this recommendation for Part 25 airplanes. In your September 16, 2013, letter you described a planned rulemaking project to revise the regulations for Part 23 airplanes and stated that the revision would include the requirements we recommend. For many years, you have said that all new airplanes comply with advisory circular (AC) 23.1419-2D, “Certification of Part 23 Airplanes for Flight in Icing Conditions,” which contains guidance regarding ice protection systems that would satisfy Safety Recommendation A-07-15. We agree with the position stated in your current letter that, because the Part 23 rulemaking will only address newly manufactured Part 23 airplanes and all newly manufactured Part 23 airplanes already comply with the AC, we do not need to wait for you to complete Part 23 rulemaking to close this recommendation. Compliance with the AC by all newly manufactured Part 23 airplanes satisfies Safety Recommendation A-07-15 in an acceptable alternate manner. Accordingly, the recommendation is classified CLOSED—ACCEPTABLE ALTERNATE ACTION. Although the actions you have taken address newly manufactured aircraft, we are concerned about in-service aircraft that have older ice protection systems without an automatic mode. We urge you to take all appropriate actions necessary to address the issue for these aircraft.

From: FAA
To: NTSB
Date: 9/24/2014
Response: -From Michael P. Huerta, Administrator: In our previous letters, the Federal Aviation Administration (FAA) reported that we amended part 25 (Amendment 25-129, 2009) and part 121 (Amendment 121-356, 2011) by adding ice protection system activation and operation regulations that address this recommendation. We also revised Advisory Circular (AC) 91-74A, Pilot Guide: Flight in Icing Conditions, and other educational material to emphasize early and often pneumatic deice boot cycling. In our September 16, 2013, letter to the Board, we reported a potential rulemaking project to re-write part 23 using higher level, performance-based language with details and means of compliance with industry standards. This part 23 rulemaking project, when initiated, will reference proposed industry standards for part 23 icing certification. These standards will include the Aviation Rulemaking Committee recommendations for ice protection system activation and operation, which reflects the previously discussed guidance in AC 23 .1419-2D, Certification of Part 23 Airplanes for Flight in Icing Conditions. This rulemaking, like AC 23 .1419-20, will only address newly manufactured part 23 airplanes. Because 100 percent of newly manufactured part 23 airplanes are being built in accordance with AC 23.14 19-20, we believe that waiting for the final rule before asking for closure is unnecessary. I believe that the FAA has effectively addressed this recommendation and consider our actions complete.

From: NTSB
To: FAA
Date: 12/3/2013
Response: We have previously stated that the FAA’s August 3, 2009, final rule satisfies this recommendation for Part 25 airplanes. We note that the FAA is continuing its review of the recommendations of its Aviation Rulemaking Committee concerning the activation and operation of ice protection systems on new airplanes certificated under Part 23 that it received in February 2012. Although formal rulemaking has not yet started, the FAA is considering revising Part 23 using performance-based language with details and means of compliance incorporated into an industry standard. Pending issuance of a final rule for Part 23 aircraft that satisfies Safety Recommendation A-07-15, the recommendation remains classified OPEN—ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 9/16/2013
Response: -From Michael P. Huerta, Administrator: In our September 27, 2012, response, the Federal Aviation Administration (FAA) reported on recommendations we received from an Aviation Rulemaking Committee (ARC) concerning activation and operation of ice protection systems on new airplanes certificated under 14 CFR part 23. We stated we were studying these recommendations and would notify the Board if we decided to pursue new part 23 icing rulemaking. We are considering a potential rulemaking effort to re-write part 23 using higher level, performance-based language with details and means of compliance incorporated into an industry standard. However, the formal rulemaking process has not yet started. The specific details of how the ARC recommendations on ice protection activation and operation for new part 23 airplanes would be incorporated will be developed as part of the rulemaking process. As previously noted, in the interim, manufacturers of part 23 airplanes have been following the guidance in Advisory Circular (AC) 23.1419-20, Certification of Part 23 Airplanes for Flight in (AFM) procedures for activating the deice boots should be to operate the deice boots in an appropriate continuous mode at the first sign of ice. Additionally, our guidance to pilots in AC 9l-74A, Pilot Guide: Flight in Icing Conditions, and educational materials stress the following: • Follow your AFM, but early and frequent boot cycling cannot hurt and can actually help airplanes with modem boots; • You may see residual ice after cycling but it is not "ice bridging"; • Cycle boots prior to configuring the airplane for approach; and • Use ice adhesion treatments as recommended by the boot manufacturer. I will keep the Board informed of the FAA's progress on this recommendation and provide an update by August 2014.

From: NTSB
To: FAA
Date: 12/18/2012
Response: We have previously stated that the FAA’s August 3, 2009, final rule meets the intent of this recommendation for Part 25 airplanes. The FAA is continuing to review a report that it received on February 10, 2012, from its Part 23 Icing Aviation Rulemaking Committee that contains recommended revisions to Part 23 to address this recommendation. Pending issuance of a final rule for Part 23 aircraft requiring that a mode be incorporated in the deice boot system that will automatically continue to cycle the deice boots once the system has been activated, Safety Recommendation A-07-15 remains classified OPEN—ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 9/27/2012
Response: -From Michael P. Huerta, Acting Administrator: In our letter dated March 8, 2012, we reported on recommendations we received from an Aviation Rulemaking Committee (ARC) concerning activation and operation of ice protection systems on new airplanes certificated under Title 14, Code of Federal Regulations (14 CFR) part 23. The Federal Aviation Administration (FAA) received a final report on February 10,2012, from this ARC that contains additional part 23 icing rulemaking recommendations. The FAA is studying these recommendations and will notify the Board if new part 23 icing rulemaking is warranted based on these recommendations. In the interim, manufacturers of part 23 airplanes have been following the guidance in Advisory Circular (AC) 23.1419-20, "Certification of Part 23 Airplanes for Flight in Icing Conditions," dated April 19, 2007. This AC recommends that the Airplane Flight Manual (AFM) procedures for activating the deice boots should be to operate the deice boots in an appropriate continuous mode at the first sign of ice. The Board's June 14, 2012, letter indicated that Safety Recommendation A-07-14 will remain classified "Open-Unacceptable Response" pending the establishment of ice protection system activation requirements in parts 91 and 135 similar to those enacted on October 21, 2011, for aircraft operated under part 121. We have reassessed the implementation of the part 121 rule and its applicability to parts 91 and 135 operations. Based on our review, we maintain that the current implementation provides an adequate level of safety as described in the preamble to the rule. Therefore, we plan no further operational rulemaking related to this issue. While we agree with the Board that removing subjectivity from activation of the airframe ice protection system would he an improvement, our review of the accident history does not support additional rulemaking. In the case of the Pueblo accident, the crew was clearly aware that icing conditions existed at the time, yet chose not to follow their AFM procedures to cycle the deicing boots prior to approach. If required in the future, the FAA will take action by issuing an airworthiness directive for specific model airplanes if warranted by service history. As additional mitigation applicable to all icing operations, the FAA conducted research on low airspeeds typical of small airplanes, which showed that the benefits of "early and often" boot cycling has to be weighed against workload in the single pilot operations of an airplane with a manual (no automatic timer) boot system. This research was published in 2007 by the American Institute of Aeronautics and Astronautics (paper number 2007-1090, "Residual and Inter-cycle Ice for Lower-Speed Aircraft with Pneumatic Boots"). We also summarized this research in AC 91-74A, "Pilot Guide: Flight in Icing Conditions." We have written educational materials and will continue to write educational materials that stress: • Following the AFM, but early and often boot cycling cannot hurt and can only help airplanes with modem boots; • Residual ice may be noted after cycling but it is not "ice bridging;" • Cycling boots prior to configuring the airplane for approach; and • Using ice adhesion treatments as recommended by the boot manufacturer. I will keep the Board informed of our progress on these safety recommendations and provide an update by August 30, 2013.

From: NTSB
To: FAA
Date: 6/14/2012
Response: We have previously stated that the FAA’s August 3, 2009, final rule meets the intent of this recommendation for Part 25 airplanes. The FAA is continuing to review a report that it received from its Part 23 Icing Aviation Rulemaking Committee that contains recommended revisions to Part 23 to address this recommendation. Pending issuance of a final rule for Part 23 aircraft that requires a mode to be incorporated in the deice boot system that will automatically continue to cycle the deice boots once the system has been activated, Safety Recommendation A-07-15 remains classified OPEN—ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 3/8/2012
Response: -From Michael P. Huerta, Acting Administrator: In the Federal Aviation Administration's (FAA) March 27, 2011, letter, we reported we published a notice of proposed rulemaking (NPRM) requiring timely activation of the airframe ice protection system (IPS) for certain airplanes used in part 121 operations that are certificated for flight in icing conditions. We published a final rule, Activation of Ice Protection (76 FR 52241) on August 22, 2011, and it became effective on October 21, 2011. The rule, which applies to airplanes with a maximum takeoff weight or less than 60,000 pounds requires either installation of ice detection equipment or changes to the airplane night or operating manual to ensure timely activation of the airframe IPS. The standards also require the airplane flight or operating manual to address initial activation, operation after initial activation, and deactivation of the airframe IPS. Depending on the IPS design, continuous operation, automatic cycling, or manual cycling can be used. For airplanes equipped with ice detection systems, the IPS must be cycled each time ice is detected. Operators must comply with these new standards by October 21, 2013. We also reported in our March 27, 2011, letter, that we received Aviation Rulemaking Committee (ARC) recommendations on February 22, 2011 concerning activation and operation of the airframe IPS for new part 23 airplane designs. In the interim, manufacturers of part 23 airplanes have been following the guidance in Advisory Circular (AC) 23.1419-2D, which recommends that the Airplane Flight Manual (AFM) procedures for activating the boots should be to operate the boots in an appropriate continuous mode at the first sign of ice. I will keep the Board informed on the progress of these safety recommendations by August 29, 2012.

From: NTSB
To: FAA
Date: 6/2/2011
Response: The FAA’s August 3, 2009, final rule meets the intent of this recommendation for Part 25 airplanes. The FAA is currently reviewing a report that it recently received from its Part 23 Icing Aviation Rulemaking Committee. The FAA indicated that the report includes recommendations for Part 23 rulemaking on IPS operations that address this recommendation. Pending issuance of a final rule for Part 23 aircraft that requires a mode to be incorporated in the deice boot system that will automatically continue to cycle the deice boots once the system has been activated, Safety Recommendation A-07-15 remains classified OPEN – ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 3/27/2011
Response: CC# 201100127: - From J. Randolph Babbitt, Administrator: In the Federal Aviation Administration's September 22, 2009 letter, we reported the Part 25 Activation of Ice Protection final rule was published on August 3, 2009. This rule addresses all newly certificated part 25 aircraft and became effective September 8, 2009. On November 23, 2009, we published a notice of proposed rulemaking (NPRM) for activation of ice protection of certain airplanes used in part 121 operations and certificated for flight in icing conditions. The proposed standards would require either installation of ice detection equipment or changes to the Airplane Flight Manual (AFM) to ensure timely activation of the airframe ice protection system. The standards would also require continuous or automatic operation of ice protection systems after activation. As discussed in this NPRM, the Aviation Rulemaking Advisory Committee's Ice Protection Harmonization Working Group concluded that similar rules for part 91 and 135 are not required. The FAA agrees and plans no action related to activation of ice protection on parts 91 and 135 at this time. The NPRM comment period closed February 22, 2010 and we anticipate publishing the final rule by July 2011. We also reported in our September 22, 2009 letter that manufacturers of part 23 airplanes have been following the guidance in Advisory Circular (AC) 23.1419-2D, which recommends operation of deicing boots at the first sign of icing and in an appropriate continuous mode. We chartered an Aviation Rulemaking Committee on February 19, 2010 to address part 23 icing regulations, which includes activation and operation of ice protection systems for new part 23 airplanes. The Part 23 Icing Aviation Rulemaking Committee delivered a report to the FAA Small Airplane Directorate on February 22, 20 II. The report includes recommendations for part 23 rulemaking on ice protection activation and operation, which address Safety Recommendations A-07-14 and -15. We are currently reviewing these recommendations to support future rulemaking efforts.

From: NTSB
To: FAA
Date: 4/27/2010
Response: The NTSB recognizes the recent progress made by the FAA in publishing its August 3, 2009, final rule revising Part 25 regulations concerning the activation of ice protection systems and its November 23, 2009, NPRM, titled Part 121 Activation of Ice Protection. However, the NTSB remains concerned about the overall slow pace in completing the recommended actions, particularly the FAA’s failure to address Parts 91 and 135 operations and its exemption of aircraft with a mean takeoff weight greater than 60,000 pounds; these serious shortcomings must be addressed before action on the recommendations can be considered successfully completed. At its February 18, 2010, meeting, the Board voted to retain the classification “Open—Acceptable Response” pending issuance of a final rule for timely activation of the ice protection system that includes flights operated under Parts 91 and 135. With regard to Safety Recommendation A-07-15, the FAA’s August 3, 2009, final rule meets the intent of the recommendation for Part 25 airplanes. The FAA now needs to implement, in a timely manner, a similar requirement for Part 23 airplanes; as stated above, the NTSB remains concerned about the slow pace of the progress to implement the needed reforms. Pending implementation of a requirement for Part 23 airplanes that use pneumatic deicing boots to have a mode incorporated that will automatically continue to cycle the deice boots once the system has been activated, Safety Recommendation A-07-15 remains classified OPEN -- ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 9/22/2009
Response: Letter Mail Controlled 10/5/2009 3:57:02 PM MC# 2090620: - From J. Randolph Babbitt, Administrator: In the FAA's May 17, 2007, letter we reported the notice of proposed rulemaking (NPRM) for the Part 25 Activation of Ice Protection, was published on April 26, 2007, and the comment period closed on July 25, 2007. The final rule, addressing all newly certificated aircraft, was published on August 3, 2009 (74 FR 38328) (enclosure 1). In January 2008, we initiated a rulemaking action to amend the regulations applicable to operators of certain airplanes used in part 121 operations and certificated for flight in icing conditions. The proposed standards would require either the installation of ice detection equipment or changes to the Airplane Flight Manual to ensure timely activation of the airframe ice protection system. We anticipate publishing the NPRM in December 2009. We also reported in our May 17, 2007, letter that manufacturers of part 23 airplanes have been following the guidance in Advisory Circular (AC) 23.1419-2D, which recommends operation of deicing boots at the first sign of icing and in an appropriate continuous mode. In March 2009, the FAA Rulemaking Management Council agreed to create an Aviation Rulemaking Committee (ARC) to address part 23 icing regulations. The ARC will be tasked with the following actions: Review the aviation rulemaking advisory committee recommendations related to the proposed part 25 regulations and guidance for supercooled large drops (SLD), mixed phase, and ice crystals, and recommend if, and how, they need to be modified for part 23; Recommend part 23 regulations that will codify the guidance in AC 23.1419-2D on activation and operations of ice protection systems, stall warning in icing conditions, and ice contaminated tailplane stall; Revise current § 23.1419 rule language on airplane performance requirements in icing that require an exemption to the 61 knot stall speed requirement in icing; and Determine if using 1 g stall speed criteria in icing is an option to reduce approach speeds and landing distances in icing conditions.

From: NTSB
To: FAA
Date: 9/10/2008
Response: On April 26, 2007, the FAA published a notice of proposed rulemaking (NPRM) for the activation of the ice protection system (IPS) in Part 25 airplanes. The NPRM proposes to require IPS activation as soon as the airplane enters icing conditions. The NPRM also proposes that after the initial IPS activation, (1) the IPS operate continuously, (2) the airplane be equipped with a system that automatically cycles the IPS, or (3) an ice detection system be provided to alert the flightcrew each time the IPS must be cycled. For several years, the FAA has been considering a change to the Part 23 regulations concerning icing issues, including the method and timing of the IPS activation. The FAA indicated that in the interim, manufacturers of Part 23 airplanes have complied with Advisory Circular (AC) 23.1419-2C, which recommends that deicing boots be operated at the first sign of icing and in an appropriate continuous mode. The Safety Board is encouraged by the issuance of the NPRM, and on July 23, 2007, provided comments to the Docket for this rulemaking. The NPRM proposes actions for Part 25 airplanes that are responsive to Safety Recommendations A-07-14 and -15. Although the Board is concerned that the FAA has not yet initiated any rulemaking for Part 23 airplanes, AC 23.1419-2C addresses the regulatory changes recommended. Pending timely issuance of the final rule for the NPRM, and issuance of regulations for Part 23 airplanes, Safety Recommendations A-07-14 and -15 are classified OPEN -- ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 5/17/2007
Response: Letter Mail Controlled 5/31/2007 8:48:32 AM MC# 2070240: - From Marion C. Blakey, Administrator: This safety recommendation supersedes A-98-91. The recommendation is the same as A-98-91 except that it was limited to turbopropeller-driven airplanes in which ice bridging is not a concern, and this recommendation expands the applicability to all pneumatic deice boot-equipped airplanes. In our previous responses to A-98-91, we provided the Board with details on proposed Parts 25 and 121 rule changes that address the activation of airframe ice protection systems. The proposed rules will not distinguish the type of powerplant and therefore these rulemaking activities remain relevant to this new recommendation. We previously reported to the Board in our October 26, 2005 letter that the regulatory evaluations on these rule changes had been delayed due to the higher priority of other safety-related rulemaking activities. In March 2006, the FAA raised the priority of the Part 25 Activation of Ice Protection rulemaking. The notice of proposed rulemaking for the Part 25 Activation of Ice Protection was published on April 26, 2007 and a copy is enclosed. The proposed Part 25 rule would require, after the initial activation of the ice protection system, that: ·The ice protection system operate continuously, or; ·The airplane be equipped with a system that automatically cycles the ice protection system, or; ·An ice detection system be provided to alert the flightcrew each time the ice protection system must be cycled. As we stated in our October 26, 2005 letter the FAA is considering an icing regulation change to Part 23 that will address the method and timing of boot activation, in addition to other icing related issues that affect Part 23 airplanes. In the interim, manufacturers of Part 23 airplanes have been following the guidance in Advisory Circular 23.1419-2C, which recommends that deicing boots be operated at the first sign of icing and in an appropriate continuous mode. The recommendations apply to all airplanes with pneumatic deicing boots. The FAA believes this action should not be taken on airplanes without modern boots due to the potential for ice bridging. Modern boots are defined as those that use small diameter tubes (up to 1.75 inches), operated at nominal pressures of at least 15 psig by excess bleed air from a turbine engine, and rapid inflation and deflation.