U.S. Department of Transportation 

FEDERAL AVIATION 

ADMINISTRATION

NOTICE OF PROPOSED RULEMAKING 

REGULATORY EVALUATION 

Revision of Airworthiness Standards for 

Normal, Utility, Acrobatic, and Commuter Category Airplanes 

14 CFR Part 23 

OFFICE OF AVIATION POLICY AND PLANS 

ECONOMIC ANALYSIS DIVISION 

Nicole Nance 

George Thurston 

October 2015 

 
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Table of Contents 

I. List of Abbreviations ............................................................................................................................ 4

II. Executive Summary ............................................................................................................................. 6

Table 1. Estimated Benefits and Costs from 2017 to 2036 (2014 $ Millions) ............................................ 9

III. Introduction/Background .............................................................................................................. 10

IV. Assumptions and Data Sources ...................................................................................................... 17

V. Fleet Discussion ................................................................................................................................ 19

Table 2. Part 23 New U.S. Certifications and Delivered Airplanes ....................................................... 22

VI. Benefits ......................................................................................................................................... 23

VI.1. Introduction .................................................................................................................................. 23

VI.2.Safety Benefits ............................................................................................................................... 24

VI.2.a. Stall ........................................................................................................................................... 24

Table 3. Fatality and Aircraft Damage Rate* ...................................................................................... 26

Table 4. Projected Future Averted Accidents, Fatalities, and Destroyed Aircraft*................................. 27

Table 5. Averted Benefit for Fatalities and Aircraft Damage from Stall Accidents* ............................... 29

VI.2.b. Icing .......................................................................................................................................... 29

Table 6. – Events Applicable to SLD .................................................................................................. 30

VI.3 Cost Savings .................................................................................................................................. 32

Table 7. Savings from Special Conditions (SC)* .................................................................................. 35

Table 8. Savings from Exemptions* .................................................................................................... 36

Table 9. Savings from Equivalent Level of Safety (ELOS)* .................................................................. 36

Table 10. Total Cost for Special Conditions, Exemptions, and ELOS* ................................................. 37

VI.4. Qualitative Benefits ....................................................................................................................... 38

VII. Costs ............................................................................................................................................. 41

VII.1. Introduction ................................................................................................................................ 41

VII.2. Discussion of Proposed Minimal to No Costs Part 23 Sections ...................................................... 42

VII.3. Discussion of Proposed Sections That Could Add Costs ................................................................ 46

VII.3.a. Annual and Hourly Wages and Benefits ..................................................................................... 47

VII.3.b. Estimated Costs for Proposed § 23.200 Controllability ................................................................ 48

Table 11. Estimate Costs for Proposed Controllability Section (2014 $) ................................................ 51

VII.3.c. §23.215 Stall Characteristics, Stall Warning, and Spins ............................................................... 51

Table 12. Estimate Costs for Proposed Stall and Spin Section (2014 $) ................................................. 53

VII.3.d. Additional Training Costs ......................................................................................................... 53
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Table 13. Training Costs (2014 $) ....................................................................................................... 56

VII.3.e. Type Certification Manual Update Costs ................................................................................... 56

Table 14. Estimate Costs for Updating Engineering Manuals (2014 $) .................................................. 57

VII.3.f. Type Certification Database Update Costs .................................................................................. 57

Table 15. Estimate Costs for Creating a Certification Database (2014 $) ............................................... 59

VII.3.g. Summary of Costs ..................................................................................................................... 59

Table 16. Total Cost Summary by Category ........................................................................................ 60

Table 17. Average Additional Cost per Type Certificate by Engine Category........................................ 60

VIII. Benefit-Cost Summary ................................................................................................................... 61

Table 18. Estimated Benefits and Costs from 2017 to 2036 (2014 $ Millions) ........................................ 61

IX. Sensitivity Discussion .................................................................................................................... 62

Table 19. Part 23 New U.S. Certifications and Delivered Airplanes ..................................................... 64

X. Appendix I ........................................................................................................................................ 66

XI. Appendix II ................................................................................................................................... 67

XII. Appendix III .................................................................................................................................. 71

XIII. Appendix IV .................................................................................................................................. 72

XIV. Appendix V ................................................................................................................................... 74

 
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I. List of Abbreviations		

AC - Advisory Circular 

ACO - Aircraft Certification Office 

APO - Aviation Policy and Plans Office 

ARC - Aviation Rulemaking Committee 

ASTM - ASTM International 

CAA - Civil Aviation Authorities 

CAR 3 - Civil Air Regulations part 3 

CFR - Code of Federal Regulations 

CO – Carbon Monoxide 

CPS - Certification Process Study 

CS-VLA - Certification Specification for Very Light Aeroplanes 

DOT - Department of Transportation 

EASA - European Aviation Safety Agency 

ELOS - Equivalent Level of Safety 

FAA - Federal Aviation Administration 

FAR - Federal Aviation Regulations 

FAMRA - Federal Aviation Modernization and Reform Act 

GA - General Aviation 

GAMA - General Aviation Manufacturers Association 

LSA - Light-Sport Aircraft 

LOC - Loss of Control 
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MOC - Means of Compliance 

NAV/COM – Navigation and Communication 

NORSEE - Non-Required Safety Enhancing Equipment 

NPRM - Notice of Proposed Rulemaking 

PBR - Performance Based Regulation 

RAD ALT – Radar Altimeter 

SARA - Small Airplane Revitalization Act 

SC – Special Condition 

TCDS - Type Certificate Data Sheet 

U.S. - United States 

USC - United States Code 

VLA - Very Light Airplane 
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II. Executive Summary

The Federal Aviation Administration (FAA) is proposing to revise the airworthiness 

standards for normal, utility, acrobatic, and commuter category part 23 airplanes by removing 

current weight and propulsion based prescriptive airworthiness requirements and replacing those 

requirements with performance and risk based regulatory standards. The majority of the 

prescriptive design requirements and methods of compliance found in current part 23 rules 

would no longer be regulatory and would be found in means of compliance documents that are 

accepted by the Administrator.1

 The FAA believes this action would provide a set of 

requirements that would allow more flexibility in part 23 airplane designs and faster adoption of 

safety enhancing technology while maintaining a higher level of safety. 

The current issue with part 23 is that the prescriptive regulatory framework does not 

readily allow the adoption of new and innovative technology. This proposed rulemaking would 

solve this issue by putting in place a performance-based regulatory structure that would result in 

the FAA accepting new means of compliance based upon industry consensus standards. Two 

examples of new and innovative technology that could be certified more quickly under this 

proposed rule are electric propulsion and computer aided flight control systems. Additionally, 

this proposal amends parts 21, 43, 91, 121, and 135 to maintain consistency with the new part 23. 

This proposed rulemaking project would: 

                                                            

1

 Means of compliance is a documented procedure used by an applicant to show compliance with part 23 

airworthiness standards, and accepted by the Administrator. A means of compliance is one method, but not the only 

method, to show compliance with a regulatory requirement. Additionally, if a procedure is used as a means of 

compliance, it must be followed completely to maintain the integrity of the means of compliance. 
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 Comply with Congressional mandates.2

 Congress passed the Federal Aviation 

Modernization and Reform Act of 2012, which requires the Administrator, in 

consultation with the aviation industry, to assess the aircraft certification and approval 

process. In response, the FAA initiated this rulemaking on September 24, 2013. 

Subsequently, on November 27, 2013 , Congress passed the Small Airplane 

Revitalization Act of 2013, which requires the FAA to issue a final rule that revises 

the certification requirements for small airplanes byo Creating a regulatory regime that will improve safety and decrease 

certification costs; 

o Setting safety objectives that will spur innovation and technology adoption; 

o Replacing prescriptive rules with performance-based regulations; and 

o Using consensus standards to clarify how safety objectives may be met by 

specific designs and technologies. 

 Reorganize part 23 into performance-based requirements by removing the detailed 

design requirements. The detailed design provisions would be identified in means of 

compliance (MOC) documents, accepted by the Administrator, to support this effort. 

The rule would also allow for greater use of consensus standards, consistent with 

guidance set forth in OMB Circular A-119, Federal Participation in the Development 

and Use of Voluntary Consensus Standards and in Conformity Assessment Activities. 

Applicants would still have the option to propose their own means of compliance as 

they do today. The process for reviewing new means of compliance would not 

change substantially from the process in place today. 

                                                            

2

 Federal Aviation Modernization and Reform Act (FAMRA) of 2012 (Public Law 112-95; 49 USC 40101 note) and 

Small Airplane Revitalization Act of 2013 (Public Law 113-53; 49 USC 44704 note). 
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 Promote harmonization and the adoption of the newly created performance-based 

airworthiness design standards as an internationally accepted approach by the 

majority of other civil aviation authorities, consistent with the direction in Executive 

Order 13609, Promoting International Regulatory Cooperation. These civil aviation 

authorities include Europe, Brazil, Canada, China and New Zealand. In addition, this 

project has been designated a pilot cooperative rulemaking project by the FAA and 

European Aviation Safety Agency (EASA). 

 Re-align part 23 requirements to promote the development of entry-level airplanes 

similar to those certified under the European Certification Specification for Very 

Light Aeroplanes (CS-VLA). 

 Increase the FAA’s ability to address future technology. 

 Amend the stall, stall warning, and spin requirements to reduce fatal accidents. 

 Improve crashworthiness by allowing new methods for occupant protection. 

 Improve part 23 airplane level of safety by allowing new type certificated airplanes to 

be approved without undue cost. 

 Address icing conditions that are currently not included in part 23 regulations. 

The goal of this proposal is to create a cost effective approach to certification in an 

adaptive regulatory environment that addresses new safety enhancing technologies and allows 

for alternative means of compliance. 

The FAA has analyzed the benefits and the costs associated with this Notice of Proposed 

Rulemaking (NPRM). The factors driving the $3.9 million expected costs of this proposal are 

the controllability, stall and spin, additional training tasks, database development, and manual 

upgrade. Benefits consist of $19.6 million in safety benefits from preventing stall and spin 
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accidents and $12.6 million in cost savings from reducing the number of special conditions, 

exemptions, and equivalent levels of safety for total benefits of $32.2 million. If the proposed 

rule saves only one human life by improving stall characteristics and stall warnings, that alone 

would result in benefits outweighing the costs. The following table shows the quantified benefits 

and costs. 

Table 1. Estimated Benefits and Costs from 2017 to 2036 (2014 $ Millions)

Costs

Safety Benefits + Cost Savings

= Total Benefits

Total	 $3.9 $19.6 +	$12.6	=	$32.2

7	percent	P.V. $3.9 $6.2 +	$5.8		=	$12.0

3	percent	P.V.	 $3.9 $11.8	+	$8.8	=	$20.6

As a result, we determined that this proposed rule would: have benefits that would justify 

its costs; not be an economically “significant regulatory action” as defined in section 3(f) of 

Executive Order 12866; be “significant” as defined in Department of Transportation’s (DOT) 

Regulatory Policies and Procedures; have a significant positive economic impact on a substantial 

number of small entities; not create obstacles to international trade; and not impose an unfunded 

mandate on state, local, or tribal governments, or on the private sector. 
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III. Introduction/Background		

In 2012, Congress passed the Federal Aviation Modernization and Reform Act (FAMRA) 

of 20123, which requires the Administrator, in consultation with the aviation industry, to conduct 

an assessment of the aircraft certification and approval process. While this proposed rulemaking 

is in response to the FAMRA, it also responds to the Small Aircraft Revitalization Act (SARA) 

of 2013.4 The SARA directs the FAA to create performance-based regulations and provide for 

the use of consensus standards to allow flexibility in the certification of new technology. This is 

different from what is currently done in certification. The current rules are product specific and 

rely on assumptions using weight and propulsion. They are also prescriptive, detailed, and 

include many “how-to” paragraphs that are more appropriate for guidance in developing means 

of compliance. This is acceptable for long-standing, traditional configurations; however, this 

approach is limiting innovation and new technology. Applicants incorporating new technology or 

innovative features are forced to use either special conditions, exemptions, or equivalent safety 

findings for certification and these processes are time consuming. The text of the SARA also 

mentions several motivations for the changes including: improving safety, reducing regulatory 

compliance costs, spurring innovation and technology adoption. Further, as the title of the law 

suggests, it is hoped that these changes would revitalize the part 23 aircraft manufacturing 

industry. The FAA believes that this proposal complies with the FAMRA and the SARA by 

improving safety, reducing regulatory compliance costs, spurring innovation, and the adoption of 

new technology. This proposal also is consistent with OMB Circular A-119, in promoting use of 

consensus standards to satisfy regulatory requirements. In addition, this proposal satisfies 

                                                            

3

 Public Law 112-95; 49 USC 40101 note 

4

 Public Law 113-53; 49 USC 44704 note 
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Executive Orders 13563, 13609, and 13610, by protecting public health, welfare, safety while 

promoting economic growth, innovation, competitiveness, and job creation, and promoting 

international regulatory cooperation. 

The FAA is conducting this rulemaking to reorganize part 23 of title 14 of the Code of 

Federal Regulations, which contains the airworthiness standards for normal, utility, acrobatic and 

commuter category airplanes. The proposal would replace current prescriptive requirements with 

performance-based regulations and streamline the approval of safety advancements by using 

performance based consensus standards to clarify how the objectives in part 23 can be met using 

specific designs and technologies. 

The FAA’s strategic initiatives communicate FAA goals to increase safety throughout 

general aviation by enabling and facilitating innovation and the development of safety enhancing 

products. This proposed rulemaking would provide an appropriate regulatory structure that 

would also allow part 23 airplanes to achieve FAA safety goals through innovation and the use 

of performance-based industry consensus safety standard, which are accepted by the 

Administrator. 

One focus area of this proposal’s increased safety goal is loss of control (LOC) accidents, 

which continues to be the largest source of fatal general aviation accidents. To address LOC 

accidents, the FAA is proposing new rule language that is performance and risk-based and would 

allow industry to develop multiple approaches through means of compliance that satisfy the new 

standard. These means of compliance would be based on a safety continuum that balances the 

level of certitude, appropriate level of safety, and acceptable risk. This means that the FAA 

accepts more risk on a simple 2-place airplane than one with 10 passengers or more. This riskbased approach to certification allows for alternative means of compliance to the same rule and 
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has already served the FAA and public well in electronics. An example application of this riskbased approach is current § 23.1309 for avionics equipment in part 23 airplanes. The FAA 

created classes of part 23 airplanes and this led to the successful introduction of glass cockpits in 

small general aviation airplanes.5

The FAA has been evaluating the way it sets standards for different types of airplanes 

certificated under part 23. In 2009, a joint FAA/industry team finalized the Part 23 Certification 

Process Study (CPS). This team reviewed the life cycle of part 23 airplanes to determine what 

provisions needed improvement. A key recommendation from this team was reorganizing part 

23 based on airplane performance and complexity rather than the existing weight and propulsion 

divisions. The team also recommended the use of means of compliance to allow for use of 

consensus standards to satisfy performance-based standards, thus permitting alternative 

approaches to certification not available today. 

In 2010, with the CPS as a foundation, the FAA initiated a part 23 regulatory review. As 

part of this review, the FAA held meetings with the public and industry to gain input on the 

future of part 23. These meetings confirmed that the public and industry supported the 

recommendations of the CPS regarding the future structure of part 23. 

In 2011, based on the results of the CPS and the part 23 regulatory reviews, the FAA 

formed the Part 23 Reorganization ARC. The committee’s chartered tasks included considering 

the recommendation of the CPS to reorganize part 23 based on airplane performance and 

complexity versus the existing weight and propulsion divisions. The ARC was also tasked to 

investigate the use of consensus standards. 

                                                            

5

 Section 23.1309 allows for different acceptable values for likelihood of failures based on the severity of the hazard, 

airplane weight, and method of propulsion. These different values encourage the incorporation of equipment that 

improves pilot situational awareness and other systems that promote the overall airplane level of safety. 
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The ARC included participants from several foreign Civil Aviation Authorities6

 and 

domestic and international members from almost every GA manufacturer of both airplanes and 

avionics. The ARC also included several Light-Sport Aircraft (LSA) manufacturers who are 

interested in certificating their products using the airworthiness standards contained in part 23. 

These manufacturers shared their insights from the GA manufacturer perspective. This 

perspective was focused on the need to certify safer airplanes by taking advantage of new safety 

enhancing technologies. 

The ARC emphasized that industry needs to develop airplanes designed to use new 

technology from the outset. The ARC noted that certification costs resulting from uncertainty 

create project risk and prevent introduction of this new technology. The ARC further noted the 

FAA’s rules are based on historical design concepts. The ARC’s observation of the part 23 

industry was that the only way to reduce risk in the certification process is to design new 

airplanes just like old airplanes. Any approach to a new airplane design is met with uncertainty 

with respect to how the FAA would address the new design. The certification of new and 

innovative products today frequently requires the use of equivalent level of safety (ELOS) 

findings, special conditions, and exemptions, resulting in uncertainty and high project costs. The 

ARC recommendations to revise part 23 echo the CPS recommendations and target the factors 

that have kept part 23 airplanes unchanged for four decades. 

Two additional factors driving the need for this rulemaking are safety and cost. In order 

to improve the future GA fleet’s safety level over that of today’s aging fleet, the FAA believes 

that industry needs to build new part 23 certificated airplanes that incorporate today’s current 

safety enhancing technologies. Although a number of new part 23 airplanes are being built, 

                                                            

6

 The international regulatory agencies included participants from Brazil, Canada, China, Europe, and New Zealand. 
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many are certified to the Civil Air Regulations part 3 (CAR 3), or very early amendment levels 

of part 23, and reflect the level of safety technology available when they were designed decades 

ago. 

Light-sport aircraft (LSA) and experimental airplanes are incorporating modern 

aerodynamics and crashworthiness technologies that sometimes employ lessons from the 

automotive industry. The FAA would like to see these technologies used to improve the safety 

of the smaller part 23 airplanes. 

Aircraft owners and manufacturers have demonstrated in the past several years that they 

are willing to purchase and install many types of non-required safety enhancing equipment in part 

23 airplanes when the equipment is perceived to be affordable. We have seen positive impacts on 

reducing both controlled flight into terrain accidents and weather related accidents that coincide 

with the increased use of some of this equipment. Examples of this equipment include: 

 GPS navigation with moving maps, 

 Terrain displays, 

 Real-time weather displays in the cockpit, 

 Traffic displays in the cockpit, 

 Angle of Attack (AoA) displays, 

 Autopilot installations, 

 Enhanced and Synthetic Vision displays, 

 Envelope protection autopilot systems, 

 Easy button for auto recovery (airplane upset, pilot disorientation, etc....), 

 Easy button for auto landing (engine failure, pilot incapacitation, etc....), 

 Backup attitude display, 

 Simplified radar altimeter (RAD ALT), 

 Installations of ballistic parachutes, 

 Installations of inflatable restraints, 

 Crush zones in structure, 

 High visibility lights, 

 Carbon Monoxide (CO) detectors, 

 Secondary radio navigation and communication (NAV/COM) with flip-flop, and 

 Amphibious Gear Advisory Systems. 
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Few GA owners or operators can afford the high cost of a new part 23 airplane that 

incorporates the latest safety enhancing features. Instead, pilots and owners are migrating to 

experimental aircraft and LSA, in part because of the lower costs. Chapter 1 of the 2013 FAA 

General Aviation Survey shows the experimental fleet has increased by 30 percent while the 

piston fleet has decreased by about 11 percent in the last 10 years. 7 

In other words, pilots believe they can get an acceptable level of safety for less cost in 

experimental aircraft and LSA than in certified CAR 3 and part 23 airplanes. The FAA believes 

that revising the standards for entry-level part 23 airplanes would achieve a more appropriate 

level of safety and reduces certification costs. 

The part 23 ARC noted that development and certification cost of working with the FAA 

to get a new part 23 entry-level airplane to market is too high. The two new U.S. manufactured 

4-place airplanes, the Cessna Corvalis and Cirrus SR-20/22, are certified to more recent 

amendment levels of part 23 and are often perceived as too expensive for typical GA uses such 

as primary flight training or rental and are not considered entry-level airplanes. These airplanes 

are priced in the $400,000 to $800,000 range, while the European Diamond DA-40, typically 

sells for $300,000-$400,000. FAA experts estimate that in early 2000 a U.S. manufacturer spent 

about $30 million to type certificate a high performance single engine airplane, and, according to 

an aircraft manufacturer, a more recent 2-seat part 23 airplane cost the company about $55 

million to certificate. The FAA’s goal with this proposal is for a new part 23 type certificate for 

a similar airplane of this size would greatly reduce the certification costs. This problem has also 

been recognized by EASA, which is actively working with several applicants to get the right 

                                                            

7

 http://www.faa.gov/data_research/aviation_data_statistics/general_aviation/ 
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oversight and cost balance for them to develop and certify new 4-place, entry-level part 23 

airplanes. 

To summarize, the purpose of this proposed rule is to revise Title 14, Code of Federal 

Regulations (14 CFR) part 23, through the current amendment level, as a set of requirements that 

focus on the safety intent of historic part 23 and allow alternative approaches to type certificate 

new part 23 airplanes through consensus standards. This rulemaking effort also follows from the 

part 23 ARC recommendations along with satisfying the intent of the FAMRA, the SARA, and 

Executive Orders 13609 and 13610. 

 
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IV. Assumptions and Data Sources

The benefit and cost analysis for the regulatory evaluation is based on the following 

factors/assumptions: 

 The analysis is conducted in constant dollars with 2014 as the base year. 

 The final rule would be effective in 2017. 

 The primary analysis period for costs and benefits extends for 20 years, from 2017 

through 2036. This period was selected because annual costs and benefits will have 

reached a steady state by 2036. 

 Future part 23 type certifications and deliveries are estimated from historical part 23 type 

certifications and deliveries. 

 Costs for the new part 23 type certifications forecasted in the “Fleet Discussion” section 

would occur in year 1 of the analysis interval. 

 Airplane deliveries from the forecasted part 23 type certificates would start in year 5 of 

the analysis interval. 

 The FAA uses a three and seven percent discount rate for the benefits and costs as 

prescribed by OMB in Circular A-4. 

 The baseline for estimating the costs and benefits of the proposed rule would be part 23, 

through the current amendment level. 

 Based on FAA Small Aircraft Directorate expert judgment, the FAA estimates 335 FAA 

part 23 certification engineers would require additional training as a result of this 

proposal. The FAA assumes that the same number of industry part 23 certification 

engineers would also require additional training as a result of this proposal. 
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 The FAA estimates this proposal would add 16 hours of training to FAA and industry 

part 23 certification engineers. 

 Since this training program would be on-line, we estimate no travel costs for the 

engineers. 

 FAA pay band tables and the Bureau of Labor Statistics (BLS) determines the hourly 

wages used to estimate the costs to the FAA and applicants. 

 Using the U.S. Department of Transportation guidance, the wage multiplier for employee 

benefits is 1.17.8

 

                                                            

8

 On January 30, 2014, the DOT published a memo on “Estimating Total Costs of Compensation Based on Wage 

Rates or Salaries.” The memo directs the FAA that when a rule requires incremental hours per existing employee, 

the wage/salary multiplier is of smaller magnitude because not all categories of employer provided benefits increase 

with additional hours worked by an individual employee. 
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V. Fleet Discussion

In order to estimate the costs and benefits of this proposed rule, we need to forecast the 

life cycle of the affected part 23 airplanes. This analysis discusses the future new part 23 type 

certifications, and their reciprocating engine, turboprop, and turbojet airplane deliveries, which 

would be affected by this proposed rulemaking. The life cycle of an airplane begins with a part 

23 type certification, then production, delivery, active service, and ends with retirement. This 

section will discuss how we forecasted each component for the length of the life cycle for future 

part 23 airplanes by using historical databases of part 23 airplanes. These historical databases 

provides the FAA with data to calculate the average number of part 23 type certificates over a 

specific historical time frame, the average number of annual deliveries per type certificate, and 

the average number of years a part 23 airplane is in production and in service. We then use these 

calculations in our forecast of future delivered airplanes affected by this proposal. 

The FAA obtained a database of historical part 23 airplane deliveries, manufactured by 

U.S. owned companies from 1947 to 2013, from the General Aviation Manufacturers 

Association (GAMA). Due to data limitations, we eliminated any airplane that was in 

production prior to 1947, after 2013, or had less than 10 years of delivery history after 1947 or 

before 2013.9

 

                                                            

9

 The following are examples of aircraft we deleted from the GAMA database in order to have a more accurate 

weighted average reflecting a full production cycle. The Navion is a United States single-engine, unpressurized, 

retractable gear, four-seat aircraft originally designed and built by North American Aviation in the 1940s. GAMA’s 

last record of the Navion production was in 1947 with no prior history provided. Similarly, Air Tractor produced the 

AT-400, AT-500, At-600, and At-800 series turboprop of agricultural aircraft starting in 2011 with only three years 

of delivery history. All American Aircraft Inc. was an aircraft manufacturer established in 1945 at Long Beach, 

California by Ernest and Gerald Adler and produced aircraft until 1948. The firm built prototypes of a light plane 

design by Ernest, the Ensign, but was unable to find buyers to make mass production viable. Alon built the A-2 

aircraft only in 1966 and 1967. Alon was then purchased and the company redesigned the fuselage from the cockpit 

back creating a new aircraft. 
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We used the FAA Type Certificate Data Sheets (TCDS) database10 from the FAA 

website, in conjunction with the GAMA delivery database, to calculate the average historical 

part 23 airplane’s production life. The TCDS contains information relevant to the certification of 

a particular airplane, such as when the airplane was initially certificated, while the GAMA 

database shows, for each part 23 type certificated airplane, how many years the airplanes were 

delivered.11 We calculated the average historical part 23 airplane’s production life is 

approximately 26 years. 

We estimated the active service time, and retirement age, of a part 23 airplane by 

analyzing the ages of all US-operated airplanes from Table 7.3 of the FAA 2013 General 

Aviation and Part 135 Activity Survey. Table 7.3 shows 184,388 airplanes in 5-year age 

groupings from 0 to over 60 years old. On average, these airplanes were in service for 34 years. 

Thus the estimated active service time, and retirement age, of a part 23 airplane is 34 years.12 

Since the life cycle equals the production life (26 years), plus the active service life which 

ends in the airplane’s retirement (34 years), we calculated the life cycle of a historical part 23 

airplane to be 60 years (26 + 34 = 60). Therefore, we use 60 years as the life cycle of a part 23 

airplane in our forecast of future type certificates and deliveries affected by this proposal. For an 

estimate of the total number of affected airplanes over 60 year life cycle, we now forecast the 

number of new type certifications and their deliveries. 

New type certifications, and the type certification’s airplane deliveries, are estimated by 

calculating the historical average number of type certificates and the average number of 

                                                            

10 http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/MainFrame?OpenFrameSet 11 Appendix 1 shows airplane manufacturers and type certification numbers we used to estimate the average 

production life. 

12 Although the FAA believes that in practice retirement ages may decline under the proposed system of certification 

as new designs become available, we are limited to the data provided in the FAA 2013 General Aviation and Part 

135 Activity Survey report and have no basis to decide by how much we should adjust our estimate. We request 

comments, with supporting data, on our retirement age estimate. 
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deliveries using the GAMA and TCDS database. We calculate the average number of historical 

type certificates from the 1940’s to current, by reciprocating engine, turboprop, and turbojet 

airplane, for each U.S. manufacturer, in Appendix 2, over decade (10-year) periods. The decade 

periods consist of the years in the following decade groups: 1940s, 1950s, 1960s, 1970s, 1980s, 

1990s, 2000s, and 2010s. Appendix 2 shows the number of new certifications, by manufacturer, 

by reciprocating engine, turboprop, or turbojet airplane, for each decade group. For example, 

Appendix 2 shows that the manufacturer Adam/AAI/Triton only had one type certificate in two 

decades; therefore the average annual number of type certificates in a 10-year period for this 

manufacturer is 0.5 (1 certification / 2 decades). 

The number of future affected airplanes equals the forecasted number of new type 

certificates multiplied by the average number of new deliveries per future type certificate. We 

base the forecast for future type certificates and deliveries of new part 23 U.S. manufactured 

airplanes upon the average number of new type certifications, and their deliveries, over the 1998 

through 2013 time period. We use the 1998 through 2013 analysis interval as a baseline for 

forecasting future part 23 type certifications and deliveries, so as to not bias our forecast by the 

explosive growth the part 23 manufacturing industry experienced during the 1970’s and 1980’s. 

Later, in the “Sensitivity Discussion” section, the FAA discusses a sensitivity analysis by using 

historical deliveries between 2008 through 2013, instead of 1998 through 2013 in order to 

determine if a shorter analysis interval affects the cost/benefit analysis. 

For each airplane manufacturer and for each of their part 23 type certifications, we 

calculate the average annual number of airplanes delivered from 1998 through 2013 by summing 

the number of deliveries by the number of years the deliveries occurred and then dividing this 

sum by the number of years the deliveries occurred. We then calculated the weighted average 
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number of airplanes per type certificate and the number of forecasted new type certificates and 

rounded the result to the nearest whole number. 

Appendix 2 shows the details we used to derive the forecast for the number of future new 

part 23 certifications and airplane delivery results and provides examples, from the tables, of 

how the results were calculated. Table 2 summarizes our estimate of part 23 U.S. airplanes that 

manufacturers would certificate and produce. 

Table 2. Part 23 New U.S. Certifications and Delivered Airplanes

 Recip TurboProp Turbojet

Weighted Average Number of AC per TC per Year 68 44 35

New Part 23 Certifications in a 10‐year Period 2 1 2

New Part 23 Certificated Airplanes deliveries per year 136 44 70

Based on this forecast of part 23 type certificates and their deliveries from Table 2, U.S. 

manufacturers would produce 136 reciprocating engine, 44 turboprop, and 70 turbojet airplanes 

annually, with deliveries beginning five years after the effective date of the rule and continuing 

for 26 years. From the second through the twenty-sixth delivery year the cumulative part 23 

fleet would grow by a total of 250 (136 + 44 + 70) airplanes annually. From the twenty-seventh 

through the thirty-fourth delivery year, the newly certificated cumulative part 23 fleet would 

remain constant. In the thirty-fifth delivery year, the model airplanes that are 34 years old would 

retire. By the sixtieth delivery year, all airplanes produced from the forecasted part 23 

certificates would be retired. Appendix 3 shows our forecast of the cumulative number of newly 

certificated part 23 airplanes delivered and affected by this proposed rule over the 60-year 

timeframe. The FAA notes that the column titled “Delivery Year” in Appendix 3 lags the first 

year of the analysis interval (or the effective date of the final rule) by five years. Similarly 

accident reduction benefits would begin five years after the rule is in effect. 
23 | Page

VI. Benefits

VI.1.	Introduction	

Part 23 standards are largely based on experience with airplanes designed in the 1950’s 

and 1960’s. Over the past five decades part 23 has become prescriptive as a result of codifying 

specific, detailed design requirements to address and respond to the introduction of new 

technologies, specific problems encountered during various certification projects, and specific 

recommendations from the National Transportation Safety Board (NTSB). While the intent of 

the prescriptive rules was to increase safety and prevent confusion or certification ambiguities, 

manufacturers felt constrained to use outdated design philosophies, which created a barrier for 

the introduction of novel safety enhancing technologies. 

Furthermore, the FAA is concerned that the current part 23 regulatory prescriptive 

structure does not effectively address the safety continuum, particularly the low performance end 

(single piston airplane) of the continuum. The safety continuum refers to higher level of safety as 

the airplane carries more people. Recent part 23 amendments have increasingly focused on highperformance, complex airplanes. These higher requirements have been applied to the lowperformance airplanes even though their risk in the safety continuum is lower. This has created 

an unintended barrier to new safety enhancing technology in low-performance airplanes. 

In 2012, Congress passed the FAMRA13, which required the Administrator, in 

consultation with the aviation industry to conduct an assessment of the aircraft certification and 

approval process. A year later, Congress passed the SARA,14 which is the basis for this 

rulemaking effort. This rulemaking addresses the SARA mandate by (1) creating a regulatory 

regime for small airplanes that will improve safety and decrease certification costs; (2) setting 

                                                            

13 Public Law 112-95; 49 USC 40101 note 

14 Public Law 113-53: 49 USC 44704 note 
24 | Page

safety objectives that will spur innovation and technology adoption; (3) replacing prescriptive 

rules with performance-based regulations; and (4) using consensus standards to clarify how 

safety objectives may be met by specific designs and technologies. 

These proposed standards begin with the safety intent of current part 23 requirements and 

adds enhanced standards for icing conditions, resistance to departure from controlled flight, and 

loss of control for multiengine airplanes as current accidents are often associated with these 

causal factors. 

VI.2.Safety	Benefits				

VI.2.a.	Stall	

The largest number of accidents for part 23 airplanes is caused by either a stall or 

departure-based LOC in flight. LOC accidents are typically initiated by an inadvertent departure 

from controlled flight. A pilot’s awareness of the state of the airplane and the airplane’s low 

speed handling characteristics are the main causes of these accidents. Stall and departure 

accidents are generally fatal if the airplane is too low for the pilot to recover before impact with 

the ground. Improving safety that reduces stall and LOC accident would save lives. The FAA is 

proposing rules for stall characteristics and stall warnings that would result in airplane designs 

that are more resistant to inadvertently departing controlled flight. 

There is another type of LOC accident that occurs in light twin-engine airplanes. 

Virtually all twin-engine airplanes flying have a minimum control speed, VMC, where the 

directional control can be maintained after the failure of one engine. This speed is above the 

airplane’s stall speed. What is unique about light twin-engine airplanes is that many of these 

airplanes have limited capability to climb on one engine. After the failure of one engine, pilots 

will instinctively try to keep the airplane flying by trying to maintain or increase altitude even as 

the airplane slows down to the VMC speed and departs controlled flight. Pilots tend to be more 
25 | Page

aware of the airplane’s stall speed, so the FAA is proposing that level 1 and 2 multiengine 

airplanes have a VMC speed that would not exceed the stall speed of the airplane for that 

configuration. After the loss of an engine, pilots would instead look for the best landing site 

immediately, maintaining control the whole way, rather than trying to climb. FAA believes that 

because manufacturers will be able to design this feature into their airframes during the 

certification process so there should be no additional costs associated with adding this feature to 

new airplane designs. 

The FAA identified 74 accidents investigated by NTSB that were caused by stall or loss 

of control from January 2008 to December 2013. These accidents are listed in Appendix IV. 

These accidents represent the type of accidents that could be prevented by the stall and LOC 

requirements in the proposed rule. An assessment is made for each accident to estimate how 

effective the proposed rule would be in preventing a similar accident. The effectiveness 

assessment results in a classification of low, medium, or high effectiveness rate. Of the 74 NTSB 

stall and LOC accidents there are 24 accidents with a high effectiveness, which had 43 fatalities, 

24 medium effectiveness accidents with 49 fatalities, and 26 low effectiveness accidents with 54 

fatalities over 6 years. All of these accidents resulted in a destroyed or substantially damaged 

aircraft. Given the high level of damage, to estimate the benefit of preventing such aircraft 

damage in the future, the FAA assumes full replacement cost for all 74 aircraft. 

To predict accidents among future type certificated aircraft that would be prevented by 

the proposed rule, the FAA estimates an accident, fatality, and destroyed aircraft rate for part 23 

aircraft using these historic accidents. Rates are estimated by dividing the average number of 
26 | Page

fatalities and destroyed aircraft in each effectiveness category by the average active number of 

airplanes.15 Table 3 shows the results of these calculations.16

Table 3. Fatality and Aircraft Damage Rate per Aircraft*

Effective

A

Avg. Yearly

Accident

(2008 – 2013)

B

Avg. Yearly

Fatalities

(2008 – 2013)

C

Avg. Yearly

Destroyed Aircraft

(2008 – 2013)

D

Avg. Number of

GA Aircraft

(2008 ‐ 2013)

A / D

Accident

Rate

B / D

Fatalities

Rate

C / D

Destroyed

Aircraft Rate

High 4 7 4 172,436 0.00002 0.00004 0.00002

Medium 4 8 4 172,436 0.00002 0.00005 0.00002

Low 4 9 4 172,436 0.00003 0.00005 0.00003

*These numbers are subject to rounding error. 

The fatality and aircraft damage rate from Table 3 is then applied to the yearly number of 

future newly certificated part 23 airplanes (reciprocating engine, turboprop, and turbojet) shown 

in Appendix III. The FAA projects that the final rule would take effect in 2017, with the first 

new type certificated aircraft being delivered in 2022. The analysis period is 20 years, but the 

accident rate applies to 15 years to account for the 5 year manufacture production cycle and 

delivery of new aircraft. In the absence of this rule, based on this methodology approximately 

0.65 high accidents, 0.65 medium accidents, 0.65 low accidents would occur on newly 

certificated part 23 airplanes over 20 years. These accidents, by effectiveness, are expected to 

result in averting a combined total of 4 fatalities and 2 destroyed aircraft as shown in Table 4. 

The estimated future accidents, fatalities, and destroyed aircraft are calculated by summing the 

rows for each category in Table 4, and then summing the high, medium, and low columns. By 

summing the results of the low, middle, and high effectiveness rates for averted accidents from 

Table 4, roughly 2 accidents are averted on newly certificated part 23 airplanes. 

                                                            

15 Table 3.1, (Fix Wing Piston, Turboprop, Turbojet) 2013-2008 General Aviation and Air Taxi Number of Active 

Aircraft by Primary Use by Aircraft Type;

https://www.faa.gov/data_research/aviation_data_statistics/general_aviation/CY2012/ 16 The FAA is unable to construct a rate per person flying or per person-mile. The FAA is not aware of any reliable 

estimates of the number of persons who flew in part 23 GA aircraft over the time period. 
27 | Page

Table 4. Projected Future Averted Accidents, Fatalities, and Destroyed Aircraft*

YEAR

Averted Accidents Averted Fatalities Aircraft Damage

High Medium Low High Medium Low High Medium Low

2017 0 0 0 0 0 0 0 0 0

2018 0 0 0 0 0 0 0 0 0

2019 0 0 0 0 0 0 0 0 0

2020 0 0 0 0 0 0 0 0 0

2021 0 0 0 0 0 0 0 0 0

2022 0.006 0.006 0.006 0.01 0.01 0.01 0.01 0.01 0.01

2023 0.012 0.012 0.013 0.02 0.02 0.03 0.01 0.01 0.01

2024 0.017 0.017 0.019 0.03 0.04 0.04 0.02 0.02 0.02

2025 0.023 0.023 0.025 0.04 0.05 0.05 0.02 0.02 0.03

2026 0.029 0.029 0.031 0.05 0.06 0.07 0.03 0.03 0.03

2027 0.035 0.035 0.038 0.06 0.07 0.08 0.03 0.03 0.04

2028 0.041 0.041 0.044 0.07 0.08 0.09 0.04 0.04 0.04

2029 0.046 0.046 0.050 0.08 0.09 0.10 0.05 0.05 0.05

2030 0.052 0.052 0.057 0.09 0.11 0.12 0.05 0.05 0.06

2031 0.058 0.058 0.063 0.10 0.12 0.13 0.06 0.06 0.06

2032 0.064 0.064 0.069 0.11 0.13 0.14 0.06 0.06 0.07

2033 0.070 0.070 0.075 0.12 0.14 0.16 0.07 0.07 0.08

2034 0.075 0.075 0.082 0.14 0.15 0.17 0.08 0.08 0.08

2035 0.081 0.081 0.088 0.15 0.17 0.18 0.08 0.08 0.09

2036 0.087 0.087 0.094 0.16 0.18 0.20 0.09 0.09 0.09

Total 0.696 0.696 0.754 1.25 1.42 1.57 0.70 0.70 0.75

*These numbers are subject to rounding error. 

The FAA used the Department of Transportation determined value of a statistical saved 

life that is $9.4 million17 in 2014. The FAA uses 3 aircraft values based on projected newly 

certificated aircraft types: a 1967 model Cessna 172 for reciprocating engine aircraft at $30,187; 

a 1982 model Beechcraft King Air C90 at $603,736 for turboprop; and a 1999 model Cessna 

Citation Jet 525 $1,455,435 for turbojet. These 2013 average retail values for destroyed aircraft 

came from the Aircraft Bluebook Price Digest Summer 2013 Edition and they are adjusted to 

2014 using Gross Domestic Product (GDP).18 Multiplying the individual future part 23 

certifications with the corresponding aircraft values provides a weighted average value for 

                                                            

17 Guidance of Treatment of the Economic Value of Statistical Life (VSL) in U.S. Department of Transportation 

Analysis - 2015 Adjustment (June 17, 2015 Memorandum) 

18 http://www.whitehouse.gov/omb/budget/Historicals/
28 | Page

destroyed aircraft. For example, out of the 250 aircraft projected for 2022, 136 are reciprocating 

engine, 44 are turboprop, and 70 are turbojet. These aircraft are projected to grow in the same 

proportion every year for a blended average retail price of $568,995 for a destroyed aircraft. 

Additionally, accidents labeled low effectiveness are assigned a .2 accident effectiveness rate, .5 

for a medium accident effectiveness rate, and .8 for high accident effectiveness rate. Table 5 

quantifies the benefits of averted fatalities by calculating the projected future averted fatalities 

from Table 4 times the VSL times the accident effectiveness rates above for the accidents labeled 

low, medium, or high. In a similar manner, Table 5 calculates the averted aircraft damage by the 

projected future averted aircraft damage from Table 4 times the average future aircraft value 

discussed above times the accident effectiveness rates. Table 5 below shows these results. As the 

fleet increases each year with additional deliveries, potential accidents increase, and so do the 

benefits of reducing such accidents. 
29 | Page

Table 5. Averted Benefit for Fatalities and Aircraft Damage from Stall Accidents*

YEAR

Effectiveness Averted Fatalities

Effectiveness Aircraft

Damage TOTAL

7 Percent

P.V.

3 Percent

P.V.

High Medium Low High Medium Low

2017 $0	 $0	 $0	 $0 $0 $0 $0	 $0 $0

2018 $0	 $0	 $0	 $0 $0 $0 $0	 $0 $0

2019 $0	 $0	 $0	 $0 $0 $0 $0	 $0 $0

2020 $0	 $0	 $0	 $0 $0 $0 $0	 $0 $0

2021 $0	 $0	 $0	 $0 $0 $0 $0	 $0 $0

2022 $78,135 $55,649 $24,531 $2,460 $1,537 $666 $162,978 $94,855 $128,656

2023 $156,270 $111,297 $49,062 $4,920 $3,075 $1,332 $325,956 $177,298 $249,818

2024 $234,406 $166,946 $73,592 $7,379 $4,612 $1,999 $488,934 $248,549 $363,813

2025 $312,541 $222,594 $98,123 $9,839 $6,150 $2,665 $651,912 $309,719 $470,955

2026 $390,676 $278,243 $122,654 $12,299 $7,687 $3,331 $814,890 $361,821 $571,548

2027 $468,811 $333,892 $147,185 $14,759 $9,224 $3,997 $977,868 $405,780 $665,881

2028 $546,946 $389,540 $171,716 $17,219 $10,762 $4,663 $1,140,846 $442,440 $754,234

2029 $625,082 $445,189 $196,247 $19,679 $12,299 $5,330 $1,303,824 $472,566 $836,875

2030 $703,217 $500,837 $220,777 $22,138 $13,836 $5,996 $1,466,802 $496,857 $914,063

2031 $781,352 $556,486 $245,308 $24,598 $15,374 $6,662 $1,629,780 $515,947 $986,044

2032 $859,487 $612,135 $269,839 $27,058 $16,911 $7,328 $1,792,758 $530,412 $1,053,056

2033 $937,622 $667,783 $294,370 $29,518 $18,449 $7,994 $1,955,736 $540,777 $1,115,329

2034 $1,015,758 $723,432 $318,901 $31,978 $19,986 $8,661 $2,118,714 $547,516 $1,173,081

2035 $1,093,893 $779,081 $343,431 $34,437 $21,523 $9,327 $2,281,692 $551,059 $1,226,522

2036 $1,172,028 $834,729 $367,962 $36,897 $23,061 $9,993 $2,444,670 $551,794 $1,275,855

Total $9,376,223 $6,677,833 $2,943,698 $295,178 $184,486 $79,944 $19,557,362 $6,247,390 $11,785,729

*These numbers are subject to rounding error. 

Estimated safety benefits of avoiding roughly 2 accidents on newly certificated part 23 

airplanes over a 20-year period sums to about $19.6 million ($6.2 million at a seven percent 

present value rate and $11.8 million at a three percent present value rate), however benefits 

would continue indefinitely into the future. 

VI.2.b.	Icing			

Currently, part 23 regulations define airplane performance, flight characteristics, 

powerplant and systems requirements for a part 23 applicant seeking optional certification for 

flight in icing conditions. Part 23 defines Appendix C to part 25 as the icing conditions for 

which the above requirements must be shown. Certain icing conditions can be encountered 

which are not addressed in Appendix C to part 25. In the 1990s, the FAA became aware that the 

icing conditions considered during the certification of airplanes and turbine aircraft engines 
30 | Page

needed to be expanded to increase the level of safety during flight in icing conditions. The FAA 

determined that the revised icing certification standards should include supercooled large drops 

(SLD, which consist of freezing drizzle and freezing rain), mixed phase, and ice crystals. 

Initially, only transport category airplanes were addressed. The FAA published amendments 25-

140 and 33-34, Airplane and Engine Certification Requirements in Supercooled Large Drop 

(SLD), Mixed Phase, and Ice Crystal Icing Conditions, on November 4, 2014 (79 FR 65508) that 

expanded icing requirements for transport category airplanes and engines. However by February 

19, 2010 an ARC was chartered to review and modify proposed part 23 icing regulations and 

provide associated guidance for part 23. 

The part 23 icing ARC examined incidents and accidents to identify those, which may be 

considered in the benefit analysis of the regulatory evaluation. Three data sources were used - 

NTSB data, the FAA Accident/Incident Data System, and the NASA Aviation Safety Reporting 

System. For a fuller discussion see their February 2012 Part 23 Icing Aviation Rulemaking 

Committee Report.19 Table 6 lists the U.S. accidents for part 23 airplanes, from 2005 to 2010, in 

which SLD was a probable cause or factor. 

Table 6. – Historical Events Applicable to SLD

DATE AC TYPE LOCATION FATAL INJURY HULL LOSS

01/03/2009 BE‐58 Brainerd, MN 0 0 SD

02/16/2007 CE‐340A Council Bluffs, IA 4 0 Yes

03/20/2006 PA‐23‐250 Emporia, KS 0 1 SD

01/25/2006 CE‐421C Carson, WA 1 0 Yes

01/11/2005 BE‐65‐E90 Rawlins, WY 3 1 Yes

SD – substantial damage 

                                                            

19 PART 23 ICING AVIATION RULEMAKING COMMITTEE REPORT (FEB 2012 - Revision B)

http://www.faa.gov/regulations_policies/rulemaking/committees/documents/media/SLD%20ARC%20Report.RevB.

Feb%2010%202012.pdf
31 | Page

Accidents listed in Table 6 prompted the part 23 icing ARC to recommend adopting most 

of the part 25 proposed rules, including the requirement to either show an airplane could safely 

fly in SLD conditions or show it can detect and safely exit those conditions. This proposed rule 

would require manufacturers, that choose to certify for flight in SLD, to meet the same safety 

standards as currently required in part 23 for the icing conditions defined in part 25, appendix C 

icing conditions. For those manufacturers who choose to prohibit flight in SLD and only certify 

to the icing conditions of part 25, appendix C,20 the proposed rule would require a means for 

detecting SLD and showing the airplane can safely exit icing conditions (detect and exit). 

Current FAA guidance in Advisory Circular 23.1419-2D would be an acceptable means of 

compliance for this detect and exit proposed rule. Based on the service history of part 23 

airplanes certified to the current icing standards, the accidents listed in Table 6 could possibly be 

prevented by the proposed requirements. The FAA reached out to industry about costs associated 

with meeting these proposed icing requirements. Industry responded that these requirements 

would not impose additional costs because many manufacturers have already equipped their 

aircraft to meet these standards for detecting and exiting SLD in accordance with current FAA 

guidance. In addition, industry noted that the standard would be optional since manufacturers are 

not required to certify their aircraft for flight in all or a portion of SLD conditions. When 

compliance is voluntary, or no change in industry practice will occur from a new regulation, the 

FAA determines both costs and benefits to be zero. 

                                                            

20 The FAA published Airplane and Engine Certification Requirements in Supercooled Large Drop, Mixed Phase, 

and Ice Crystal Icing Conditions, on November 4, 2014 (79 FR 65508) that expanded 14 CFR parts 25 and 33 icing 

requirements. 
32 | Page

VI.3	Cost	Savings

The current part 23 aircraft certification and approval process is prescriptive with specific 

performance and design requirements that impact the industry’s ability to introduce new 

technology or to modify aircraft. The FAA accommodates the introduction of new and 

innovative technology or modifications by requiring an applicant to provide additional 

information that explains the deviation from the existing rule. This process typically results in 

the issuance of special conditions, exemptions, and equivalent level of safety findings.21 To 

streamline the certification process and encourage the installation of new technology, the FAA is 

proposing a rule that would replace the prescriptive requirements found currently in part 23, thus 

obviating the need for many of the exemptions, etc. 

The FAA proposes revising part 23 airworthiness standards by replacing current 

prescriptive design requirements with risk and performance based regulatory standards. To 

comply with the new performance-based standards, manufacturers could continue to use the 

existing design standards as a means of compliance, but could also use industry consensus 

standards, such as the ones currently being developed by ASTM, as well as any other means the 

manufacturer develops to demonstrate compliance with the standard. This use of consensus 

standards is not a new practice. Industry standards bodies like RTCA, Inc., SAE International 

(SAE), ASTM International (ASTM), and the European Organization for Civil Aviation 

Equipment (EUROCAE) have provided consensus standards that have been accepted as means 

of compliance for decades. The FAA believes the proposed rule would provide a broad set of 

                                                            

21 Special Conditions give the manufacturer permission to build the aircraft, engine or propeller with additional 

capabilities not addressed in the regulations. A petition for exemption is a request to the FAA by an individual or 

entity asking for relief from the requirements of a regulation. Equivalent level of safety findings are made when 

literal compliance with a certification regulation cannot be shown and compensating factors exist which can be 

shown to provide an equivalent level of safety. 

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgWebcomponents.nsf/HomeFrame?OpenFrameset
33 | Page

requirements that would allow more flexibility in airplane designs and faster adoption of safety 

enhancing technology and significantly reduce the need and cost incurred for special conditions, 

exemptions and equivalent level of safety findings. 

A reduction in the number of special conditions, ELOS, and exemptions would reduce 

paperwork and processing time for both the FAA and industry. It would also maintain the 

fundamental safety requirements from the current part 23 regulations but allow more flexibility 

in airplane designs, faster adoption of safety enhancing technology, and reduce the regulatory 

cost burden. To estimate savings driven by this change, the FAA counted the special conditions, 

ELOS, and exemption applications submitted to the FAA for part 23 aircraft between 2012 and 

2013 and divided the number by two years for an average of 47 applications per year.22 The ARC 

report offered a similar average of 37 applications per year.23 Additionally, the FAA counted the 

number of pages per application for all 47 applications to obtain an average number of pages per 

application. For special conditions, there were approximately 21 pages, 16 pages for an 

exemption, and 15 pages per ELOS application. The FAA assumes that the applicant and each 

FAA office that reviews the application spend 8 hours on research, coordination, and review per 

page. The ARC also noted “an ELOS finding or exemption can take the FAA between 4 to12 

months to develop and approve. The applicant spends roughly the same amount of time as the 

FAA in proposing what they need and responding to FAA questions for SC, exemption, or 

ELOS.”24 

                                                            

22 https://my.faa.gov/org/linebusiness/avs/offices/air/tools/cert.html 23 A report from the 14 CFR Part 23 Reorganization Aviation Rulemaking Committee to the Federal Aviation 

Administration; Recommendation for increasing the safety of small general aviation airplanes certificated to 14 CFR 

part 23, June 5, 2013, Table 7.1 – Special Conditions, Exemptions, Equivalent Safety Findings, Page 55 24 Ibid., 54.
34 | Page

The number of applications is multiplied by the number of pages and by the hourly wage 

for the applicant and different FAA offices to account for the cost to the FAA and the applicant. 

The estimated hourly wage is $74.10 for a Small Airplane Directorate employee25, $50.75 for an 

Aircraft Certificate Office employee26, and $60.58 for an engineer27 employed by the applicant. 

Annual cost equals the sum of the associated costs of special conditions, exemptions, plus 

equivalent level of safety. Yearly cost totals roughly $502,469 for the Small Airplane 

Directorate, $344,172 for Aircraft Certificate Offices, and $410,823 for the applicants. Tables 7, 

8, and 9 show cost by office and applicant as well as by special condition, exemption, and ELOS. 

   

                                                            

25 2014 FAA Bay Band, Average K Band Salary (Rest of the U.S.) plus wage multiplier for benefits 

https://employees.faa.gov/org/staffoffices/ahr/program_policies/policy_guidance/hr_policies/hrpm/comp/comp_ref/

2014payadjustment/

26 2014 FAA Bay Band, Average I Band Salary (Rest of the U.S.) plus wage multiplier for benefits 

https://employees.faa.gov/org/staffoffices/ahr/program_policies/policy_guidance/hr_policies/hrpm/comp/comp_ref/

2014payadjustment/ 

27 National Occupational Employment and Wage Estimates United States, May 2014; Aerospace Engineer mean 

hourly wage, NAIC code 17-2011 plus wage multiplier for benefits http://www.bls.gov/oes/current/oes_nat.htm#17-

0000 . A more detailed discussion is provided in the “Costs” section below.
35 | Page

Table 7. Savings from Special Conditions (SC)*

Part 23 Section

Avg. Number

of SC         

(2012‐2013)

Avg.

Number of

Pages

FAA SAD FAA ACO Applicant

Man‐hours Savings      Man‐hours Savings       Man‐

hours   Savings     

143 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

171 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

173 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

175 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

177 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

251 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

361 1 20.8 166 $12,330 166 $8,445 166 $10,081 

562 1 20.8 166 $12,330 166 $8,445 166 $10,081 

572 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

573 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

574 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

613 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

627 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

629 1.5 20.8 250 $18,495 250 $12,668 250 $15,121 

901 1 20.8 166 $12,330 166 $8,445 166 $10,081 

939 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

951 1 20.8 166 $12,330 166 $8,445 166 $10,081 

961 1 20.8 166 $12,330 166 $8,445 166 $10,081 

973 1 20.8 166 $12,330 166 $8,445 166 $10,081 

977 1.5 20.8 250 $18,495 250 $12,668 250 $15,121 

1141 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

1301 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

1305 1 20.8 166 $12,330 166 $8,445 166 $10,081 

1308 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

1309 1 20.8 166 $12,330 166 $8,445 166 $10,081 

1329 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

1337 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

1521 1 20.8 166 $12,330 166 $8,445 166 $10,081 

1557 1 20.8 166 $12,330 166 $8,445 166 $10,081 

3Pt Restraint 

with Airbag 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

Inflatable 

Restraint 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

Electronic 

Engine Controls 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

Fuel Jettisoning 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

Load Alleviation 

System 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

Side Facing Seat 

with Airbag 0.5 20.8 83 $6,165 83 $4,223 83 $5,040 

Totals 24.5 728 4077 $302,080 4077 $206,914 4077 $246,983 

*These numbers are subject to rounding error.
36| Page

Table 8. Savings from Exemptions*

Part 23

Section

Avg. Number

Exemptions

(2012‐2013)

Avg. Number

of Pages

FAA SAD FAA ACO Applicant

Man‐hours Savings    Man‐hours   Savings      Man‐hours   Savings   

1359 0.5 15.6 62.4 $4,624 62 $3,167 62 $3,780 

1549 0.5 15.6 62.4 $4,624 62 $3,167 62 $3,780 

177 0.5 15.6 62.4 $4,624 62 $3,167 62 $3,780 

49 1 15.6 124.8 $9,247 125 $6,334 125 $7,561 

562 1 15.6 124.8 $9,247 125 $6,334 125 $7,561 

1419 0.5 15.6 62.4 $4,624 62 $3,167 62 $3,780 

Totals 4 94 499 $36,989 499 $25,336 499 $30,243

*These numbers are subject to rounding error. 

Table 9. Savings from Equivalent Level of Safety (ELOS)*

Part 23

Section

Avg. Number

ELOS          

(2012‐2013)

Avg. Number

of Pages

FAA SAD FAA ACO Applicant

Man‐hours   Savings      Man‐hours   Savings      Man‐hours   Savings     

145 1 14.9 119.2 $8,832 119 $6,050 119 $7,221 

207 1 14.9 119.2 $8,832 119 $6,050 119 $7,221 

672 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

777 1.5 14.9 178.8 $13,249 179 $9,075 179 $10,832 

779 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

781 1.5 14.9 178.8 $13,249 179 $9,075 179 $10,832 

807 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

815 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

841 1 14.9 119.2 $8,832 119 $6,050 119 $7,221 

973 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1092 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1145 1 14.9 119.2 $8,832 119 $6,050 119 $7,221 

1305 1.5 14.9 178.8 $13,249 179 $9,075 179 $10,832 

1311 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1353 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1357 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1397 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1401 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1419 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1443 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1505 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1545 0.5 14.9 59.6 $4,416 60 $3,025 60 $3,611 

1549 2.5 14.9 298 $22,081 298 $15,125 298 $18,054 

Totals 19 343 2205 $163,400 2205 $111,923 2205 $133,597 

*These numbers are subject to rounding error. 

Using these yearly cost estimates, over 20 years $25.1 million in man-hours would be 

spent on applying for and processing special conditions, exemptions, and ELOS. However under 

the proposed rule, the FAA believes that the need to demonstrate compliance through special 

conditions, exemptions, or ELOS would largely be eliminated. Instead new products will simply 

need to demonstrate compliance by following consensus standards acceptable to the 

Administrator, or by submitting their own proposed means of compliance using the process 
37| Page

outlined in proposed AC 23.10.28 As a conservative estimate, the FAA estimates that special 

conditions, exemptions, and ELOS would be reduced by half for a savings to the FAA and 

applicant of roughly $12.6 million ($5.8 million present value). Savings by year is shown in the 

chart below. The FAA asks for comment regarding the amount of reduction in the alternative 

means of compliance. 

Table 10. Total Cost for Special Conditions, Exemptions, and ELOS*

Year FAA SAD FAA ACO Applicant Total  

2017 $251,235 $172,086 $205,411 $628,732	

2018 $251,235 $172,086 $205,411 $628,732	

2019 $251,235 $172,086 $205,411 $628,732	

2020 $251,235 $172,086 $205,411 $628,732	

2021 $251,235 $172,086 $205,411 $628,732	

2022 $251,235 $172,086 $205,411 $628,732	

2023 $251,235 $172,086 $205,411 $628,732	

2024 $251,235 $172,086 $205,411 $628,732	

2025 $251,235 $172,086 $205,411 $628,732	

2026 $251,235 $172,086 $205,411 $628,732	

2027 $251,235 $172,086 $205,411 $628,732	

2028 $251,235 $172,086 $205,411 $628,732	

2029 $251,235 $172,086 $205,411 $628,732	

2030 $251,235 $172,086 $205,411 $628,732	

2031 $251,235 $172,086 $205,411 $628,732	

2032 $251,235 $172,086 $205,411 $628,732	

2033 $251,235 $172,086 $205,411 $628,732	

2034 $251,235 $172,086 $205,411 $628,732	

2035 $251,235 $172,086 $205,411 $628,732	

2036 $251,235 $172,086 $205,411 $628,732	

Total $5,024,694 $3,441,724 $4,108,227 $12,574,646

*These numbers are subject to rounding error. 

Additionally, current standards for the production approval can create a barrier for 

adoption of new, non-required and low risk articles suitable for installation on type-certificated 

aircraft in the existing fleet. To encourage and enable the installation of voluntary safety 

enhancements on these aircraft, the FAA is proposing to provide applicants with an alternative 

means to obtain FAA approval to produce replacement and modification articles. This proposed 

                                                            

28 See Section VI. Discussion of the Proposed Regulatory Amendments of the preamble for a discussion of how this 

might be accomplished. 
38| Page

change would provide a means that could be used to streamline the approval of these articles, 

which would facilitate the retrofit of safety enhancing equipment in the existing fleet. Examples 

of such articles include carbon monoxide detectors, weather display systems, clocks, small handheld fire extinguishers, and flashlights. In many cases, these articles are “off-the-shelf products.” 

It is frequently difficult for a person to install these articles on a type certificated aircraft because 

the level of design and production details necessary for these articles to meet the provisions of 

current § 21.9, as expected for more critical articles, is frequently unavailable. 

Therefore, the FAA is proposing to revise § 21.9, Replacement and Modification 

Articles, to provide applicants with an alternative method to obtain FAA approval to produce 

replacement and modification articles. The FAA intends to use the flexibility provided by this 

proposed change to streamline the approval process for non-required safety enhancing equipment 

and other articles that pose little or no risk exposure to aircraft occupants and the public. 

Moreover, an applicant for supplemental type certificate can elect to comply with the new 

requirement, instead of the original certification basis for the airplane and could possibly see the 

same benefits expected for new type certificates. The FAA received 211 part 23 STCs in 2012 

and 210 in 2013. The FAA asserts that a certain number of STCs submitted yearly would benefit 

from this requirement and specifically requests comments regarding whether the proposed 

change would safely facilitate retrofit of low risk articles and by how much. 

VI.4.	Qualitative	Benefits	

The FAA Office of Aviation Policy and Plans (APO) asked the Volpe Center to 

investigate whether performance-based regulation (PBR) or streamlining of regulatory approval 
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via use of industry consensus standards in other sectors has resulted in the positive outcomes 

anticipated in relation to the part 23 reorganization. 

Regarding the use of PBR, the Volpe research found the following: 

 The available literature is practically unanimous in the assertion that PBR would result in 

lower costs for industry, i.e. higher efficiency. 

 Performance-based standards will not by themselves spur innovation and progress toward 

new safety features. 

 If the regulating agency wishes to promote diffusion of certain technologies, PBR is 

capable of serving that function. 

 To the extent that design standards inhibit competition in a market, moving to 

performance standards may increase competition and foster growth in the market. In 

addition, the use of PBR can facilitate the use of cost saving measures and remove 

barriers to innovation. In turn, lower prices and innovative product features can spur 

demand and revitalize an industry. 

 Based on the experience of the LSA segment, it appears that using consensus standards as 

a way of streamlining the aircraft certification process has resulted in lower costs of 

certification and facilitated the introduction of new and innovative designs. 

Based on the Volpe findings, it appears likely that adopting PBR as a method of safety 

regulation for part 23 small general aviation aircraft could result in many of the positive impacts 

mentioned as objectives of the “Small Aircraft Revitalization Act of 2013.” However, the 

magnitude of the positive impacts would be determined by how much freedom and flexibility the 

new performance standards actually provide. Providing guidance on “means of compliance” 

through consensus standards would assist manufacturers in developing methods for meeting the 
40| Page

performance standards. However, Volpe warns that those consensus standards may turn out to be 

de facto design standards and erode the potential benefits of adopting PBR. The FAA would 

require that manufacturers submit consensus standards for FAA acceptance to avoid this 

scenario. 

For more details, see “The Economic and Safety Impacts of Performance-Based 

Regulation and Consensus Standards” Volpe document in the docket. 

 
41| Page

VII. Costs

VII.1. Introduction		

The	Federal	Aviation	Administration	(FAA)	is	proposing	to	revise	the	airworthiness	

standards	for	normal,	utility,	acrobatic,	and	commuter	category	part	23	airplanes	by	removing	

current	weight	and	propulsion	based	prescriptive	airworthiness	requirements	and	replacing	those	

requirements	with	performance	and	risk	based	regulatory	standards. The majority of the 

prescriptive design requirements and methods of compliance found in current rules would no 

longer be regulatory and would be found in means of compliance documents after the publication 

of the final rule. The FAA believes this action would provide a set of requirements that would 

allow more flexibility in airplane designs and faster adoption of safety enhancing technology 

while maintaining a high level of safety. 

The FAA is also reorganizing most of the current part 23 sections. In the NPRM, the 

FAA provides a table mapping the current CFR sections to the proposed sections. 29 The FAA 

expects that many of the current part 23 requirements would not change but will be transferred to 

other documents, and therefore would be cost/safety neutral. These other documents include 

MOC, AC, Airworthiness Design Standards (ADS), and ASTM documents. In the following 

section, we discuss this in more detail. 

In December 2014, the FAA met and discussed the proposed part 23 requirements with 

the part 23 Reorganization ARC. We then provided the ARC with a draft document, which 

included the provisions we intended to propose. The costs estimated in this section are based on 

the discussions and documents FAA provided the ARC in that meeting. 

                                                            

29 The NPRM can be found at http://www.regulations.gov/ at the docket number FAA-2015-1621. The table also 

shows the new requirements discussed below that the FAA is proposing in this rulemaking. 
42| Page

This chapter also discusses the FAA’s estimate of costs for the proposed changes that 

would add requirements to the part 23 certification process for new applicants. The other costs 

include additional training costs for engineers to familiarize themselves with the new rule, type 

certification manual update costs, and type certification database update costs. 

VII.2.	Discussion	of	Proposed	Minimal	to	No	Costs	Part	23	Sections		

Currently, the ASTM standards organization is developing a set of consensus standards 

based on the current part 23 regulations for FAA acceptance. The ASTM standards would be 

one way, but not the only way, to demonstrate compliance to the proposed part 23 performance 

standards.30 

At this time, the FAA has not accepted any consensus standards as a means of 

compliance. The FAA would still conduct an assessment to make sure that the airplane design 

and the proposed consensus standards meet the performance standards in the current regulations. 

In addition, once the FAA has accepted a design feature in a consensus standard, other designers 

and manufacturers that wish to include that feature could reference the standard. The assumption 

of minimal cost to the proposal’s changes assumes these consensus standards become available 

for use as a means of compliance.31

The FAA would continue to accept compliance with current part 23 as a means of 

compliance for new type certifications with the exception of the new provisions, which would 

need to be included in the certification. The proposed regulations would make the retrofit of new 

                                                            

30 If a manufacturer chose to use its own means of compliance, we would use the same process used today to 

evaluate alternatives. 

31 FAA believes that it may experience some workload increase during the transition period to using the new rule 

along with means of compliance. But this has been accounted for in the transition training effort and we believe that 

the increased means of compliance review will be offset by the reduced number of issue paper related rulemaking 

(special conditions). We also believe that in the long term, after FAA and industry are comfortable with the new 

system, the workload on the FAA will be lower than today. 
43| Page

technology more straightforward without the need for as many special conditions, equivalent 

level of safety findings (ELOS), or exemptions. The FAA believes the proposed regulations 

would also remove barriers to bringing new, safer airplane designs to market with similar 

benefits. The proposal would decrease the time and expense to the FAA and the industry of 

working in the current prescriptive regulatory environment while concurrently improving the 

safety and health of GA. The international aviation industry, including representatives from the 

world’s leading aviation authorities not only agree with this approach, but are currently working 

with us to meet this goal. This proposal would clear paths to compliance for a multitude of 

technologies, which would be available through the consensus standards approach. For the 

majority of this proposal, the means of compliance with the FAA’s proposed performance 

regulations would be cost/safety neutral because the means of compliance in the ASTM or other 

documents would be no more burdensome than today’s prescriptive part 23 requirements 

established through the current amendment level. 

The FAA seeks comments from manufacturers on the effect of this proposal’s changes on 

the part 23 type certification process. Specifically, the FAA is seeking data on how the costs 

would change between today’s type certification processes, versus the type certification 

processes proposed in this rulemaking. The FAA is also seeking comments, with supporting 

documentation, on the flexibility this proposal would offer for the type certification of new part 

23 airplanes and what manufacturers would be doing differently because of this proposal. 

We are also proposing to promote the development of entry-level airplanes similar to 

those certified in other countries under the European certification specifications for very light 

aeroplanes (CS-VLA) by expanding the range of airplanes that can be certificated under part 23. 

Airplanes that meet the requirements of CS-VLA can be currently certificated in accordance with 
44| Page

§ 21.17 for special classes of aircraft. The proposal would permit a manufacturer to use part 23 

to certificate an airplane designed in accordance with the European CS-VLA standards. The 

FAA believes that this proposal would be cost/safety neutral for airplanes that meet CS-VLA. 

The FAA requests comments on any increase in costs from permitting a manufacturer to use part 

23 to certificate an airplane designed in accordance with the European CS-VLA standards or § 

21.17. 

Proposed § 23.5 would require that airplanes approved for spins be certificated to 

aerobatic standards. An airplane designed with traditional handling qualities and designed to 

allow spin training is more susceptible to inadvertent departure from controlled flight. The FAA 

believes that maintaining the current utility category for airplanes approved for spinning and 

limited aerobatic maneuvers would negate the single largest safety gain expected from this 

rulemaking action—the significant reduction in inadvertent stall-related departures from 

controlled flight. The FAA believes this new requirement would have little effect on the 

industry. The only time the FAA requires spin training is for the instructor certificate, and that is 

for only one flight. In addition, many flight schools are already using acrobatic airplanes for spin 

training because they spin better. And finally, consider that it would take a decade or more 

before the current fleet of utility category airplanes would have to be replaced, we do not see this 

as an issue. 

Also, the FAA proposes moving away from the current stall characteristics and spin 

testing approach to address the largest cause of fatal accidents in small airplanes. Proposed § 

23.215 in subpart B would omit the one turn/three second spin requirement for normal category 

airplanes, but it would increase the stall handling characteristics and stall warning requirements 

so the airplane would be substantially more resistant to stall-based departures than the current 
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rules require. This is a technical discussion addressing some of the flight schools concerns about 

spin training. The argument that the FAA has heard from the flight schools is that because they 

have not had problems we should not change the proposed rule from what we have today. We 

compromised in that as long as we can have the safer, stall resistant airplane when a family of 

three or four flies the airplane, they can have an airplane that with a maintenance change to a 

different configuration, could be used for spin training. The proposed rule changes behind this 

topic are discussed in the Preamble and the additional cost are discussed below in the 

“Discussion of Proposed Sections That Could Add Costs” section. 

This proposal is also adding regulations to improve the safety of part 23 airplanes 

certified for flight in icing by addressing icing conditions that are not currently included in part 

23. This would be accomplished by incorporating recommendations from the part 23 Icing 

ARC. Prior to the Part 23 Reorganization Aviation Rulemaking Committee (ARC), the Part 23 

Icing ARC recommended revising part 23 to incorporate supercooled large drop (SLD) icing 

requirements into subparts B, E, and F. The proposed icing regulations would require airplanes 

certificated to fly into known icing conditions to meet the same safety standards in SLD icing 

conditions as currently required in part 25, if the applicant chooses to certify the airplane for 

flight in all or a portion of SLD. For those airplanes that only certify to the icing conditions in 

appendix C to part 25, the proposed regulations would require a means for detecting SLDs and 

showing the airplane can safely exit the icing conditions. The FAA determined that the service 

history of part 23 airplanes certified to the latest icing standards have shown these standards to 

provide an adequate level of safety for SLD “detect and exit” airplanes. 

In December 2014, the FAA met and discussed the proposed icing requirements with the 

part 23 Reorganization ARC. The icing requirements discussed with the ARC do not differ from 
46| Page

those set forth in this proposal. Since this meeting, industry has reviewed the icing requirements 

we provided along with the draft ASTM icing standards. Based on this information, industry 

believes the proposed icing requirements are cost and safety neutral as the proposal reflects 

current industry practices for detecting and safely exiting SLD conditions. Industry does not 

believe they will certify a part 23 airplane for flight in SLD conditions. The FAA requests 

comments, with supporting documentation, on any incremental costs proposed §§ 23.257 and 

23.1419 could add to the new part 23 certification process. 

Additionally, this proposal would amend parts 21, 43, 91, 121, and 135 to maintain 

consistency and alignment with the new part 23. These would be conforming changes and are 

not expected to add costs. 

VII.3.	Discussion	of	Proposed	Sections	That	Could	Add	Costs			

When the FAA and members from the part 23 Reorganization ARC met in December 

2014, the FAA provided the ARC with a draft document, which included provisions we intended 

to propose. The FAA believes this proposal would not have any increase in scope from the draft 

document we provided. The costs estimated in this section are based on the discussions and 

documents the FAA provided the ARC in the December 2014 meeting and the assumption that 

the baseline for estimating the costs of the proposed rule would be part 23, through the current 

amendment level. 

The FAA analyzed the expected costs of the proposed rule over the analysis interval. The 

major factors driving the expected costs of this proposal are the additional training tasks, 

database development, and documentation to FAA and industry part 23 certification engineers. 

The following sections discuss the FAA estimate of the number of part 23 certification and 

industry engineers who would be have to receive training because of this proposed rulemaking. 
47| Page

We also discuss the FAA estimate of their salaries in order to estimate training costs. We then 

discuss the provisions that add costs, and the methodology the FAA employed, to estimate the 

total incremental costs of this proposed rule, over what is currently required, based upon FAA 

and industry unit cost estimates. 

VII.3.a.	Annual	and	Hourly	Wages	and	Benefits		

In this section, we discuss the part 23 certification engineering wages the FAA uses in 

this analysis. This section also discusses the source we used for the wages. 

The proposed requirements contains provisions for persons to perform additional 

engineering duties in designing, constructing, training, and testing airplanes from what is 

currently required in part 23 up through the current amendment level. These engineers may 

conduct basic and applied research to evaluate adaptability of materials and equipment to 

airplane design and manufacture and may recommend improvements in testing equipment and 

techniques. 

In May 2014, BLS published the National Industry-Specific Occupational Employment 

and Wage Estimates for Support Activities for Air Transportation. The North American Industry 

Classification System (NAICS) code for Support Activities for Air Transportation is 488100.32 

The major group for Aerospace Engineers under the 488100 NAICS code is 17-2011. 33 The 

FAA believes that the 17-2011 survey is the appropriate wage to estimate the salary of the part 

23 certification engineers affected by the proposed rule. The BLS survey lists the mean hourly 

wage for aerospace engineer as $51.78. The cost analysis uses the mean hourly wage of $51.78 

for part 23 certification engineers to estimate the additional costs the proposal adds for training 

                                                            

32 http://www.bls.gov/oes/current/naics4_488100.htm#17-0000 

33 http://www.bls.gov/oes/current/oes172011.htm 
48| Page

tasks. The FAA notes that the survey lists the annual mean salary range for aerospace engineers, 

by area in the continental United States, from $66,110 to $155,240. 

In addition, aerospace engineer benefits (such as health benefits, vacation, sick time, etc.) 

must be added to estimate the costs for this analysis. Using the guidance from the “Employer 

Costs for Employee Compensation – December 2014” study of employee benefits,

34 the FAA 

uses the wage multiplier for benefits equaling 1.17. Therefore, the FAA calculated the mean 

hourly wage, plus benefits, for a part 23 certification engineer to be $60.58 ($51.78 + $8.80). 

VII.3.b.	Estimated	Costs	for	Proposed	§	23.200	Controllability	

There is a detailed discussion in the Preamble on the FAA proposing to eliminate 

commuter, utility, and acrobatic airplane categories in part 23, retaining only normal category for 

all new part 23 type certificated airplane design approvals and instead proposing the following 

airplane certification levels: 

 Level 1 – for airplanes with a maximum seating configuration of 0 to 1 passengers. 

 Level 2 – for airplanes with a maximum seating configuration of 2 to 6 passengers. 

 Level 3 – for airplanes with a maximum seating configuration of 7 to 9 passengers. 

 Level 4 – for airplanes with a maximum seating configuration of 10 to 19 passengers. 

In order to estimate costs for §§ 23.200 and 23.215, the following two sections discuss the 

mapping of the reciprocating, turboprop, and turbojet airplanes presented in the “Fleet 

Discussion” section into the proposed airplane certification levels. 

                                                            

34 On January 30, 2014, the DOT published a memo on “Estimating Total Costs of Compensation Based on Wage 

Rates or Salaries”. The memo directs the FAA that when a rule requires incremental hours per existing employee, 

the wage/salary multiplier is of smaller magnitude because not all categories of employer provided benefits increase 

with additional hours worked by an individual employee. 
49| Page

Proposed § 23.200 should prevent level 1 and 2 multiengine airplanes from losing 

directional control after a critical loss of thrust. The FAA and industry believe that proposed § 

23.200 would increase the burden for certain multi-engine airplanes because it may require 

additional testing costs and include a cost for a change to a limitation or performance number in 

the flight manual. 

At the time of this writing, there was no consensus between the FAA and the ARC on a 

means to demonstrate compliance with proposed § 23.200. What is currently being discussed is 

a relatively simple test that could be performed as part of a single test plan doing multiple tests 

on a flight. Industry believes that this simple test to comply with the proposed change and has 

provided the FAA with estimated costs of $100,000 to $200,000. Therefore, the FAA uses 

$150,000 (($100,000 + $200,000)/2) as an average cost to demonstrate and test for this more 

prescriptive requirement. This would be a one-time cost per new type certification. 

In addition, proposed § 23.200 could result in a change to a limitation or a performance 

number in the flight manual. Industry believes that this proposed change could cost from 

$100,000 to $150,000. Therefore, the FAA uses $125,000 (($100,000 + $150,000)/2) as an 

average cost for this proposed change. 

There would also be additional paperwork associated with this requirement that is not 

part of the costs discussed above. The FAA estimates the paperwork costs for these proposed 

provisions by multiplying the number of hours the FAA estimates for each page of paperwork, 

by the number of pages for the training courseware, or flight manual, by the hourly rate of the 

person responsible for the update. The Small Aircraft Directorate of the FAA provided average 

hourly times and the number of additional pages of paperwork the proposal would add. The 

FAA estimates that this section would add a total of four pages to the training courseware and 
50| Page

flight manual.  The FAA also estimates that it would take a part 23 certification engineer eight 

hours to complete the one page required for each new type certification. The eight hours to 

complete a page includes the research, coordination, and review each document requires. 

Therefore, the FAA estimates the total paperwork costs for proposed controllability 

section would be about $1,939 (8 hours * 4 pages * $60.58 per hour) in 2014 dollars. 

From Appendix 2 and the “Fleet Discussion” section above, we calculated that there 

would be two part 23 reciprocating engine future type certificates. From Appendix 2 and the 

“Fleet Discussion” section, 96% of the historical reciprocating engine airplanes delivered had 

one-engine; therefore, proposed § 23.200 would not add costs to future type certificated part 23 

reciprocating engine airplane. 

Also from the Appendix 2 and the “Fleet Discussion” section, 100 percent of the 

historical turbojet airplanes delivered had two engines, but about 46 percent could be produced 

with only six seats. Therefore the FAA assumes that proposed §23.200 would add costs to one 

of the new turbo jet airplane type certificates calculated above. 

Again, from Appendix 2 and the “Fleet Discussion” section, 56 percent of the historical 

turboprop airplanes delivered had two engines, but 97 percent have greater than six seats. 

Therefore the FAA assumes that proposed § 23.200 would not add costs to future type 

certificated multiengine turboprop airplanes. 

The FAA and industry believe that for the rest of the changes in this proposed 

controllability section, there is no significant cost impact because there is no difference than 

what is required today, although in the future, there may be some cost savings once consensus 

standards have been developed. 

Table 11 shows the total costs for the proposed changes to the controllability section. 
51| Page

Table 11. Estimate Costs for Proposed Controllability Section (2014 $)

Airplane

Number of Estimated

New Type Certificates

Affected by § 23.200

Training

Costs

Changes to

Flight Manual

Paper

Work Total

Recip	 0	 $150,000		 $125,000		 $1,939		 $0		

Turboprop	 0	 $150,000		 $125,000		 $1,939		 $0		

Turbojet	 1	 $150,000		 $125,000		 $1,939		 $276,939		

Total		 		 		 		 		 $276,939		

*These numbers are subject to rounding error. 

The FAA notes that a multi-engine part 23 aircraft manufacturer could decide it wants to 

comply with § 23.200(b) by making the airplane capable of climbing after a critical loss by 

installing larger engines. Both the FAA and industry believes that this option would reduce the 

utility of the airplane so much it would not be a marketable product. We request comments, with 

supporting cost documentation, on the feasibility of part 23 aircraft manufacturer deciding if it 

wants to make the airplane capable of climbing after a critical loss by installing larger engines. 

VII.3.c.	§23.215	Stall	Characteristics,	Stall	Warning,	and	Spins	

The FAA is proposing to increase the stall requirements for level 1and level 2 airplanes 

and level 3 single engine airplanes to provide some level of spin resistance or protection from 

inadvertently departing controlled flight. The FAA and industry believes that the majority of the 

proposed changes to § 23.215 are not significantly different than what is currently required today 

and therefore the testing costs for this new proposed requirement would not be significant. 

Section 23.215(b) is a new requirement that would likely increase the burden for all 

newly certificated, level 1 or level 2, single and multi-engine reciprocating, turboprop, and 

turbojet airplanes not certified for aerobatics. In addition, this section also applies to all newly 

certificated level 3 part 23 airplanes with one-engine not certified for aerobatics. Section 
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23.215(b) requires these airplanes must not have a tendency to inadvertently depart controlled 

flight. Industry was not able to provide an estimate on this provision’s effect on multi-engine 

airplanes. Since 1980 there have only been two light twin engine (level 2) airplanes certified and 

the certifications were validations of foreign designs. Thus, we seek comment, with supporting 

documentation, on the cost of this provision and any plans for U.S. manufacturers to certificate 

future new light twin engine airplanes. 

From Appendix 2 and the “Fleet Discussion” section, 100 percent of the historical 

reciprocating engine airplanes had six or fewer seats and would fall under the level 1 or level 2 

airplane classification. Therefore the two new part 23 reciprocating engine type certificates, 

calculated in the “Fleet Discussion” section, would have to comply with this section. 

In addition, 97 percent of the historical turboprop airplanes, analyzed in Appendix 2 and 

the “Fleet Discussion” section, had 10 or more seats. Therefore, we assume that any new part 23 

turboprop airplane certifications would be a level 4 airplane that would continue to meet the 

current requirements for this section and therefore have no additional costs. 

Lastly, 92% of the historical turbojet airplanes, analyzed in Appendix 2 and the “Fleet 

Discussion” section, have fewer than 10 seats. Also from Appendix 2 and the “Fleet Discussion” 

section, we estimated that there would be two new future part 23 turbojet type certificates. 

Therefore, two new part 23 turbojet engine U.S. type certificates would have to comply with this 

section. 

The FAA is unaware of any U.S. manufacturer who currently has made an application to 

type certificate a part 23 multi-engine level 1 or level 2 airplane. Industry has also expressed 

there is not sufficient demand for new level 1 or level 2 type certificated multi-engine airplanes. 

Therefore, the FAA assumes there would be no costs for level 1 or level 2 multi-engine airplanes 
53| Page

and we request comments, with supporting cost documentation and estimates on the time frames 

and number of new U.S. manufactured level 1 or level 2 multi-engine type certificates, for this 

assumption. 

According to discussions with industry, the FAA believes that level 3 multiengine 

airplanes and level 4 airplanes continue to meet current requirements and, therefore, future type 

certificates of these airplanes would incur no additional costs from this proposed requirement. 

Industry believes that this proposed change could cost somewhere in the range of 

$100,000 to $150,000 for a new type certificated airplane. Therefore, the FAA uses $125,000 

(($100,000 + $150,000)/2) as an average cost to demonstrate and test for this proposed change. 

This would be a one-time cost per new type certification. 

The FAA and industry believe that for the rest of changes in this section there is no 

significant cost impact because there is no difference than what is required today. 

Table 12 shows the total costs for the proposed changes to the controllability section. 

Table 12. Estimate Costs for Proposed Stall and Spin Section (2014 $)

Airplane

Number of Estimated New

Type Certificates Costs Total

Recip 2 $125,000   $250,000  

Turboprop 0 $125,000   $0  

Turbojet 2 $125,000   $250,000  

Total         $500,000  

VII.3.d.	Additional	Training	Costs		

FAA and industry certification engineers would need training on how to implement the 

new requirements. A good part of the training would be involved in explaining the new process 

and how to relate the accepted means of compliance to the new regulations. In this section, we 

first discuss our estimate of the number of part 23 FAA and industry certification engineers that 
54| Page

would require additional training because of this proposed rulemaking. Next, we describe the 

costs to develop the training programs necessary to implement the rule. We then estimate the 

training costs for this proposal to both FAA and industry. 

The Planning and Program Management Division of the FAA Aircraft Certification 

Service (AIR-500) provided the number of engineers who support the part 23 certification 

requirements. Once the rule is published, there would be an initial effort on both the part of the 

FAA and industry to train their engineers. 

There are currently 669 part 23 FAA certification engineers and we expect the number of 

engineers will stay reasonably flat until the time a final rule is published. The FAA estimates 

that 50 percent of these part 23 FAA certification engineers, or 335, would require additional 

training to implement this proposal.35 The FAA assumes, based on FAA Small Aircraft 

Directorate expert judgment, that the same number of industry part 23 certification engineers 

would also require additional training necessary to implement the rule; therefore, we assume that 

there are 335 industry certification engineers who would also require training. 

Due to retirement or attrition, the FAA and industry would have to hire new part 23 

certification engineers. The initial training program for new engineers would include the training 

necessary to implement the rule when they are hired, and therefore we believe that there would 

not be any recurrent costs from this proposal to newly hired part 23 FAA and industry 

certification engineers. 

The FAA estimates that it would cost $250,000 to develop the structured training on part 

23 for the FAA certification engineer staff. The cost to deliver the training is dependent on the 

                                                            

35 Most of the work in the FAA certification offices is part 25 or part 25 based. We believe that engineers who will 

be needed to focus on part 23 projects and older small airplanes represent about half of our engineering workforce. 
55| Page

type of training developed, but at this time, we plan on providing the course on-line so that the 

course could be delivered to FAA staff. The FAA estimates that it would take most engineers 

two days (16 hours) to take the on-line training. This would be a one-time cost per new type 

certification. The FAA is anticipating the two days of training would encompass the following 

topics: 

1. Background/history – addressing why we are making this change to part 23, 

2. Rule language – go over the specific new language, how it relates to amendment 

62 languages, and the intent of the new language, 

3. ASTM Means of Compliance – go over the means of compliance and how it links 

to the rule language. This would be interwoven with item #2, and 

4. Work through a number of examples focusing on difficult and unusual STC 

projects. 

The FAA assumes it would cost the same for industry to develop their structured training 

class and that the same number of industry part 23 certification engineers would also require 

additional training from this proposal. 

The FAA notes that any paperwork costs discussed in this section would be part of the 

initial $250,000 cost to develop the training materials. 

Therefore, the FAA estimates the total training costs to FAA and industry part 23 

certification engineers would be about $500,000 (2 * $250,000) to develop the on-line training 

material and $649,000 (2 * (16 hours * 335 engineers * $60.58 per hour)) to train the engineers. 

Table 13 shows the calculation of these training costs to both the FAA and industry. 
56| Page

Table 13. Training Costs (2014 $)

  

Development of

on‐line training

Training

Hours

Number of

Engineers

Hourly

Wage Total

FAA $250,000   16 335 $60.58 $574,709  

Industry $250,000   16   335   $60.58   $574,709  

Total               $1,149,418  

*These numbers are subject to rounding error. 

VII.3.e.	Type	Certification	Manual	Update	Costs		

The FAA is expecting part 23 airplane manufacturers to update their engineering 

procedures manuals to reflect the changes from this proposed rulemaking. However, most of the 

engineering procedures manuals are not written around the requirements of part 23, but around 

the requirements of part 21. Since the part 23 changes would have minimal impact on the part 

21 requirements, there should be little change in the engineering procedures manuals. 

Conversations with industry indicate that there may need to be some changes to the 

engineering manuals to describe how the accepted means of compliance must be related to the 

regulations. Depending on the complexity of each company’s manual, industry estimates that 

these changes could run from about $50,000 up to $200,000. This would be a one-time cost per 

new type certification. 

Since the FAA is unable to determine the complexity of each company’s manual, we 

assume that the manufacturers of the two new part 23 reciprocating engine airplane type 

certifications, discussed in the “Fleet Discussion” section, would spend $50,000 to make the 

changes to the engineering manual. We also assume that the one new part 23 turboprop airplane 

certification and the two new part 23 turbojet airplane certifications, discussed in the “Fleet 

Discussion” section, would use the more complex and costly approach of $200,000. 

The FAA notes that either the simple approach or the more complex approach to updating 

the manuals could also either take place in-house or could be contracted out to a consultant. 
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Table 14 shows the total costs for the proposed changes to the controllability section. 

Table 14. Estimate Costs for Updating Engineering Manuals (2014 $)

Airplane

Number of Estimated

New Type Certificates

Simple

Approach

Complex

Approach Total

Recip 2 $50,000 $0 $100,000  

Turboprop 1 $0   $200,000   $200,000  

Turbojet 2 $0   $200,000   $400,000  

Total            $700,000  

*These numbers are subject to rounding error. 

VII.3.f.	Type	Certification	Database	Update	Costs		

Currently, manufacturers have certification compliance databases that are used to create a 

compliance checklist that is used to identify who is finding compliance to each regulation, how 

they are finding compliance, (i.e. analysis, test, etc.), and where the substantiation is documented 

such as a report number, revision, title, etc. The manufacturers may also tie a schedule or other 

facts pertaining to the regulation in the compliance checklist database. This may be one of the 

more significant one-time costs to revise the programs to accommodate the new proposed 

regulation because this database has to reference the methods of compliance associated with the 

proposed regulation, or this could be a cross-reference between the various old regulations and 

the proposed regulations, or this could contain the testing or analysis necessary to comply with 

the proposal. 

The FAA understands from discussions with industry that part 23 airplane manufacturers 

plan to use a product similar to Microsoft EXCEL to create this certification database in a 

spreadsheet with cross reference tables. This approach may not be acceptable for large 

companies with large production capacity, more complicated airplanes, and multiple certification 

processes. 
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For a company that is using an EXCEL spreadsheet to perform this tracking, industry 

estimates that the total cost to make the necessary changes to a spreadsheet database to range 

from $100,000 to $200,000 per certification. Therefore, the FAA uses $150,000 (($100,000 + 

$200,000)/2) as an average cost to make the necessary changes to a spreadsheet database for a 

small manufacturer. Since the FAA is unable to determine whether a manufacturer would be 

using a simple EXCEL spreadsheet to create this certification database, we assume that the 

manufacturers of the two new part 23 reciprocating engine airplane type certifications, estimated 

in the “Fleet Discussion” section, would use the simple approach. 

For manufacturers that have a production capacity and multiple certification processes, 

industry estimates that a programmer could spend up to six months of full time programing to 

make this change to a simple compliance database. A more complex program may take between 

one to one and a half years for a programmer to make the necessary programming changes. 

Industry estimates that the cost for the programming changes to the certification database would 

range from $100,000 to $300,000. Therefore, the FAA uses $200,000 (($100,000 + 

$300,000)/2) as an average cost to make the necessary programming changes to a more complex 

certification database. 

In addition, this task would also require some engineering support effort that industry 

estimates could be about 25 percent to 50 percent of the time that a programmer takes. Industry 

estimates that the cost for engineer support could range from $37,500 to $225,000, depending on 

the complexity of the aircraft, to assist in making the programming changes to the certification 

database.36 Therefore, the FAA uses $131,250 (($37,500 + $225,000)/2) as an average cost for 

                                                            

36 Part 23 aircraft range from simple reversible control, low technology aircraft to complex irreversible control, high 

technology aircraft which affects the amount of programming necessary for a certification database. 
59| Page

engineering support to make the necessary changes to a more complex certification database. 

This would be a one-time cost per new type certification. 

The FAA notes that either the simple EXCEL approach or the more complex approach to 

creating this certification database could also either take place in house or could be contracted 

out to a consultant. 

Since the FAA is unable to determine whether a manufacturer would have a more 

complex production capacity and multiple certification processes involved with creating this 

certification database, we assume that the manufacturers of the one new part 23 turboprop 

airplane certifications, and two new part 23 turbojet airplane certifications, estimated in the 

“Fleet Discussion” section would use the more complex and costly approach. 

Table 15 shows the total costs for the proposed changes to the controllability section. 

Table 15. Estimate Costs for Creating a Certification Database (2014 $)

Airplane

Number of Estimated

New Type Certificates

EXCEL

approach

Programming

support  

Engineering

support Total

Recip 2 $150,000   $0   $0   $300,000  

Turboprop 1 $0   $200,000   $131,250   $331,250  

Turbojet 2 $0 $200,000 $131,250   $662,500

Total               $1,293,750  

VII.3.g.	Summary	of	Costs		

The proposed rules’ major costs are the engineer training costs and the certification 

database creation costs. Additional costs would also accrue from the controllability and stall 

sections that increase scope over current requirements and the manual upgrade costs. 
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In Table 16, we summarize the total estimated compliance costs by category. The FAA 

notes that since we assumed that all costs occurred in Year 1 of the analysis interval, the 2014 

dollar costs equal the present value costs.

Table 16. Total Cost Summary by Category

  

Type of Cost

Total Costs

(2014$) and P.V.

§23.200 Controllability $276,939

§23.215 Stall characteristics, stall warning, and spins $500,000

Engineer Training Costs $1,149,418

Certification Database Costs $1,293,750

Manual Upgrade Costs $700,000

Total Costs $3,920,106

*These numbers are subject to rounding error. 

The FAA estimated the average additional cost from this proposal, per reciprocating 

engine airplane, turboprop airplane, and turbojet airplane type certification by dividing the total 

costs by category the number of estimated new certifications from the “Fleet Discussion” 

section. We then summed these average costs by category. The results are shown in Table 17 

below. 

Table 17. Average Additional Cost per Type Certificate by Engine Category

Engine §23.200 §23.215 Training Database Manual Total

Recip $0		 $125,000		 $229,884		 $150,000	 $50,000		 $554,884		

TP $0		 $0		 $229,884		 $331,250	 $200,000	 $761,134		

TJ $276,939		 $125,000		 $229,884		 $331,250	 $200,000	 $1,163,072		

*These numbers are subject to rounding error. 

 
61| Page

VIII. Benefit‐Cost Summary

The major safety benefit of this proposed rule is to add stall characteristics and stall 

warnings that would result in airplane designs that are more resistant to inadvertently depart 

controlled flight. The largest number of accidents for part 23 airplanes involves a stall or 

departure-based LOC in flight. Additional benefits are that the current part 23 regulations are 

prescriptive and hinder the industry’s ability to introduce new technology; this proposal would 

result in cost savings by streamlining the certification process and encouraging new and 

innovative technology. Streamlining the certification process would reduce the issuance of 

special conditions, exemptions, and equivalent level of safety findings. 

The proposed rule’s major costs are the engineer training costs and the certification 

database creation costs. Additional costs would also accrue from the controllability and stall 

sections that increase scope over current requirements and the manual upgrade costs. 

In addition, if the proposed rule would save only one human life by improving stall 

characteristics and stall warnings that alone would result in benefits outweighing the costs. 

Accordingly, the FAA has determined that the proposed rule would be net beneficial. 

The FAA has analyzed the benefits and the costs associated with this NPRM. The 

following table shows these results. 

Table 18. Estimated Benefits and Costs from 2017 to 2036 (2014 $ Millions)

Costs

Safety Benefits + Cost Savings

= Total Benefits

Total	 $3.9 $19.6 +	$12.6	=	$32.2

7	percent	P.V. $3.9 $6.2 +	$5.8		=	$12.0

3	percent	P.V.	 $3.9 $11.8	+	$8.8	=	$20.6
62| Page

IX. Sensitivity Discussion

Earlier in this analysis the FAA discussed both the “The Small Airplane Revitalization 

Act of 2013” and how performance-based regulations, or streamlining of regulatory approval via 

use of industry consensus standards, could result in decreasing certification costs. The use of 

consensus standards as a means of compliance to the proposed performance based regulations 

review could reduce the cost of introducing new designs and increase the number of future part 

23 type certificates. 

ASTM International has developed light sport aircraft (LSA) consensus standards. In a 

paper available on the ASTM website, ASTM cites the success of its LSA consensus standards 

resulting in numerous new aircraft designs has been developed. The authors of the paper believe 

the LSA consensus standards substantially reduce the cost to certify a new LSA aircraft model 

relative to the traditional part 21 requirements.37 In 2008, ASTM reported that 76 new aircraft 

designs were developed as a result of the ASTM design standards.38 Currently there are over 130 

new LSA designs suggesting that over the last six years, on average nine new designs per year 

have been introduced. 

The FAA believes that once promulgated, this proposal could enable new part 23 

manufacturers to both enter the marketplace and permit current part 23 manufacturers to develop 

new cost-effective part 23 airplanes that are cheaper to design and purchase. 

Although it is difficult for the FAA to quantify the outcome, we believe that through the 

flexibilities offered in this proposal, the general aviation community could reverse the trend of 

                                                            

37 Stephenson, James and Deborah Stephenson, “Light Sport Aircraft Industry Takes Flight on ASTM International 

Standards,” ASTM Standardization News November/December 2008. 38 Ibid. 
63| Page

decreasing part 23 certified fleet (11 percent in the last 10 years as determined from the 2013 

FAA General Aviation Survey) and could increase deliveries. 

The FAA believes that after this proposal becomes effective, part 23 manufacturers may 

seek certification for at least one or two new reciprocating engine airplanes in addition to what 

we estimated in the “Fleet Discussion” section. As a result of this proposal, every new part 23 

type certification could add costs but since the benefits for these new type certifications are a 

function of the aircraft deliveries, the benefits would also increase proportionately. 

We request comments, with supporting documentation, on the positive effects of this 

proposed rulemaking to the marketplace. 

Sensitivity Analysis Using Historical Deliveries between 2008 through 2013 

As a check of how the number of deliveries affects the costs and benefits, the FAA 

conducted a sensitivity analysis using historical deliveries between 2008 through 2013 instead of 

1998 through 2013 to forecast future deliveries to determine the effect on the cost benefits of this 

rulemaking. 

Utilizing the same methodology from the “Fleet Discussion” section to calculate the 

growth of the expected affected future part 23 fleet, we analyzed the annual airplane deliveries 

from U.S. manufacturers between 2008 through 2013. For each airplane manufacturer and for 

each of their type certifications, we calculated the average annual number of airplanes delivered 

from 2008 through 2013. While the turboprop and the turbojet market is essentially the same in 

this shorter period of analysis, the reciprocating airplane market has well less than half the 

airplanes produced over the longer 1998 through 2013 analysis period. Table 19 summarizes our 

estimate of part 23 U.S. airplanes that manufacturers would certificate and produce for this 
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sensitivity analysis. The sensitivity analysis resulted in one less type certification and a 

significant drop in deliveries for reciprocating airplanes over the base case forecast. For the 

sensitivity analysis, the base case forecast of the number of type certifications remained constant 

and deliveries slightly increased for turboprop and turbojet airplanes. 

Table 19. Part 23 New U.S. Certifications and Delivered Airplanes

 Recip TurboProp Turbojet

Weighted Average Number of AC per TC per Year 49 48 36

New Part 23 Certifications in a 10‐year Period 1 1 2

New Part 23 Certificated Airplanes deliveries per year 49 48 72

Using the values from Table 19, and following the same methodology from the “Fleet 

Discussion” section for this sensitivity analysis, with no change in the average production life 

and the 34 years airplane service life, we forecasted the cumulative number of newly certificated 

part 23 airplanes, delivered and retired annually. Appendix 5 shows these results. 

For this sensitivity analysis, we then estimated benefits by flowing the adjusted 

forecasted part 23 cumulative deliveries from Appendix 5, through the same benefit 

methodology, the same fatality and aircraft damage rates, the same projected future averted 

accidents, fatalities, and destroyed aircraft, the same value of saved life, the same aircraft values, 

and the same blended average retail price of a destroyed aircraft from the “Safety Benefit” 

section. 

Similarly, for this sensitivity analysis, we estimated costs using forecasted new part 23 

certifications from Table 19, with the same methodology, the same annual and hourly wages and 

benefits, the same industry provided unit costs, the same FAA estimated hours and pages for 

paperwork, and the same training time from the “Costs” section. 
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Since the decline in the number of reciprocating airplane deliveries for the sensitivity 

analysis is well less than half the airplanes produced over the longer 1998 through 2013 analysis 

period, the safety benefits declined by about 20 percent. The was only a slight drop in costs for 

the sensitivity analysis because of the reduction in type certificates for reciprocating airplanes 

and no change in the type certifications for turboprop and turbojet airplanes. 

Table 20 shows for this sensitivity analysis, the benefits also exceed the costs. 

Table 20. Sensitivity Analysis Using Historical Deliveries between 2008 through 2013 

to Estimate Benefits and Costs from 2017 to 2036 (2014 $ Millions)

Costs

Safety Benefits + Cost Savings

= Total Benefits

Total	 $3.6 $13.4 +	$12.6	=	$26.0

7	percent	P.V. $3.6 $4.3 +	$5.8		=	$10.1

3	percent	P.V.	 $3.6 $8.1	+	$8.8	=	$16.9

 
66| Page

X. Appendix I
67| Page

XI. Appendix II

For an example of how we calculated the average annual number of airplanes delivered per manufacturer, the fol

the manufacturer Adam/AAI/Triton, since they only delivered aircraft for the three years 2005, 2006 and 2007, th

airplanes delivered is 3 ((2+4+3) / 3). 

*These numbers are subject to rounding error.
68| Page

*These numbers are subject to rounding error. 

 
69| Page

For an example of how we calculated the weighted average number of airplanes per type 

certificate, the following table shows that for turboprops, we used the formula 

( ( (0.25*86.7)+ (0.5*14.6) + (0.29*58.6) ) / (0.25+0.5+0.29) )and then rounded the result to the 

nearest whole number 44. The following table also shows and example of how we calculated the 

new part 23 certificates for turboprops was (0.25+0.5+0.29) and then rounded to the nearest 

whole number 1. 

This table shows how we calculated the number of new certifications, by manufacturer, by 

reciprocating engine, turboprop, and turbojet airplane, for each decade group. 

*These numbers are subject to rounding error. 

 
70| Page

This table is used in the cost section to calculate the percentages for the historical airplanes 

delivered with one or two engines and various seat groupings. 

Type 

Certificate Type Engines # of a/c Seats 

3A12 R 1 4,688 4 

3A13 R 1 3,390 4 

3A15 R 1 844 6 

3A16 R 2 551 4-6 

3A23 R 1 346 4-5 

A00003SE R 1 764 4 

A00009DE R 1 9 6 

A21CE R 1 516 2 

A4CE R 1 1,462 6 

A-759 R 1 420 2 

3A20 T 2 582 10 

A00007SE T 1 102 4 

A24CE T 2 1292 13 

A37CE T 1 1,387 10 

A00001AC J 2 4 7 

A00010WI J 2 292 6-7 

A00014WI J 2 446 6 

A1WI J 2 1,123 6-10 
71| Page

XII. Appendix III
72| Page

XIII. Appendix IV

NTSB Stall and Spin Loss of Control Accidents

NTSB Number Date Fatalities Acft_Make Acft_Model Damage Applicability to 

Rule 

MIA08FA038 1/12/2008 3 CESSNA 172L SUBS Low

CHI08FA061 1/12/2008 4 CESSNA 340 SUBS Medium

DFW08FA060 2/2/2008 2 CIRRUS SR22 DEST Low

LAX08FA068 2/27/2008 3 MOONEY M20C DEST Low

ANC08FA037 2/27/2008 1 CESSNA 170B SUBS Medium

MIA08FA081 3/20/2008 1 CIRRUS SR22 SUBS Medium

NYC08FA148 3/24/2008 1 PIPER PA 28-161 SUBS High

MIA08FA091 4/18/2008 1 AeroFab Lake LA-250 SUBS Medium

DEN08FA078 4/19/2008 2 CESSNA P206 DEST High

CHI08FA133 5/12/2008 2 BEECH V35 DEST Medium

NYC08FA189 5/22/2008 2 Grumman AA-1C DEST High

LAX08FA152 5/23/2008 4 BEECH V35B DEST Medium

DFW08LA161 6/7/2008 1 CESSNA 150M SUBS Medium

DFW08FA170 6/29/2008 5 CESSNA U206F DEST Low

LAX08LA211 7/2/2008 1 CESSNA 152 DEST High

DFW08FA190 7/19/2008 3 PIPER PA-22 DEST High

LAX08FA244 7/24/2008 2 CESSNA A185F DEST Medium

SEA08FA175 8/9/2008 2 CESSNA 180K SUBS Low

CHI08FA248 8/14/2008 1 BEECH 58TC DEST High

DEN08FA152 9/7/2008 2 GULFSTREAM AA-5A DEST High

ANC08LA122 9/10/2008 1 PIPER PA-18 SUBS High

DFW08FA228 9/14/2008 1 ACAC 7GCBC SUBS Medium

DFW08FA233 9/18/2008 2 PIPER PA-60-602P DEST Low

DFW08FA237 9/28/2008 2 CESSNA 320D SUBS Low

ANC09FA001 10/1/2008 2 CESSNA U206C DEST Low

ERA09FA053 11/13/2008 2 CIRRUS SR22 SUBS Low

ERA09FA068 11/24/2008 3 BEECH 95-B55 (T4 DEST Medium

WPR09FA062 12/20/2008 1 DIAMOND DA 20-C1 SUBS Low

ERA09LA131 1/6/2009 1 PIPER PA-25-235 SUBS Low

CEN09FA147 2/1/2009 1 MOONEY M20C SUBS High

WPR09FA112 2/5/2009 3 BEECH A36 SUBS High

ERA09FA169 2/17/2009 2 CIRRUS SR20 SUBS High

CEN09FA178 2/27/2009 3 CESSNA 182M SUBS Low

WPR09FA150 3/14/2009 2 PIPER PA28-236 DEST High

WPR09FA200 4/18/2009 2 CHAMPION 7ECA SUBS Low

WPR09FA258 5/22/2009 4 CESSNA 320D SUBS High

CEN09FA340 6/7/2009 2 Gulfstream AA-5B SUBS Medium

CEN09FA363 6/16/2009 1 CIRRUS SR22 DEST Low

WPR09FA398 8/16/2009 2 CESSNA 152 SUBS Medium

CEN10LA031 10/27/2009 2 AERONCA 7AC DEST Medium

WPR10FA078 12/10/2009 2 PIPER PA-38-112 SUBS Low

CEN10FA114 2/6/2010 4 BEECH A36 SUBS Medium

ERA10FA154 2/27/2010 1 BEECH P35 SUBS High

ERA10FA178 3/18/2010 1 BEECH 95 SUBS High

ERA10LA233 4/16/2010 1 CESSNA 172H SUBS Low

CEN10FA233 5/2/2010 2 PIPER PA46 SUBS High

ERA10FA259 5/10/2010 2 CIRRUS SR22 SUBS Medium

CEN10FA324 6/17/2010 5 CESSNA T310R SUBS Medium

CEN10FA364 7/1/2010 2 BEECH F33A SUBS Low

CEN10FA385 7/11/2010 3 CESSNA 177B SUBS Low

WPR10FA383 8/4/2010 1 CIRRUS SR22 SUBS High
73| Page

ERA10FA404 8/7/2010 2 BEECH 58 SUBS Low

CEN10FA493 8/23/2010 2 CESSNA 310C SUBS Low

WPR11FA029 10/25/2010 3 CESSNA 340A SUBS High

CEN11FA075 11/17/2010 1 Hawker/Beechcraft A36 SUBS High

WPR11FA050 11/17/2010 2 DIAMOND DA20-C1 SUBS High

CEN11LA194 2/15/2011 1 TAYLORCRAFT DCO-65 SUBS Low

CEN11FA267 4/4/2011 1 CIRRUS SR-22 SUBS Medium

WPR11FA248 6/4/2011 1 PIPER PA-24-250 SUBS Low

ERA11FA332 6/9/2011 2 CESSNA 152 SUBS Medium

ERA11FA354 6/23/2011 2 BEECH C24R SUBS High

WPR11FA331 7/17/2011 2 MOONEY M20F SUBS Medium

WPR11FA335 7/18/2011 3 MOONEY M20C SUBS Low

ERA12FA146 1/16/2012 1 Aerostar PA-60-601P SUBS Medium

ERA12FA163 1/29/2012 1 PIPER PA-28-180 SUBS High

CEN12FA164 2/20/2012 2 PIPER PA-24-250 SUBS High

CEN12FA170 2/26/2012 2 MOONEY M20E SUBS High

ERA12FA303 4/27/2012 1 CIRRUS SR22 SUBS Medium

CEN12FA617 9/9/2012 1 BEECH A36 SUBS Medium

CEN13FA002 10/3/2012 2 CIRRUS SR22 SUBS Medium

CEN13FA060 11/18/2012 2 GRUMMAN AA-1B SUBS Medium

WPR13FA141 3/9/2013 1 MAULE M5 SUBS Low

WPR13FA236 5/18/2013 2 CESSNA 170B SUBS Low	

CEN14FA084 12/12/2013 3 PIPER PA 24-250 SUBS Low

 
74| Page

XIV. Appendix V