20924 Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2007–27654; Notice No. 

07–07] 

RIN 2120–AI90 

Activation of Ice Protection 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The Federal Aviation 

Administration proposes to amend the 

airworthiness standards applicable to 

transport category airplanes certificated 

for flight in icing conditions. The 

proposed standards would require a 

means to ensure timely activation of the 

airframe ice protection system. This 

proposed regulation is the result of 

information gathered from a review of 

icing accidents and incidents, and is 

intended to improve the level of safety 

for new airplane designs for operations 

in icing conditions. 

DATES: Send your comments on or 

before July 25, 2007. 

ADDRESSES: You may send comments 

identified by Docket Number FAA– 

2007–27654 using any of the following 

methods: 

• DOT Docket Web site: Go to http:// 

dms.dot.gov and follow the instructions 

for sending your comments 

electronically. 

• Government-wide rulemaking Web 

site: Go to http://www.regulations.gov 

and follow the instructions for sending 

your comments electronically. 

• Mail: Docket Management Facility; 

U.S. Department of Transportation, 400 

Seventh Street, SW., Nassif Building, 

Room PL–401, Washington, DC 20590– 

0001. 

• Fax: 1–202–493–2251. 

• Hand Delivery: Room PL–401 on 

the plaza level of the Nassif Building, 

400 Seventh Street, SW., Washington, 

DC, between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

For more information on the 

rulemaking process, see the 

SUPPLEMENTARY INFORMATION section of 

this document. 

Privacy: We will post all comments 

we receive, without change, to http:// 

dms.dot.gov, including any personal 

information you provide. For more 

information, see the Privacy Act 

discussion in the SUPPLEMENTARY

INFORMATION section of this document. 

Docket: To read background 

documents or comments received, go to 

http://dms.dot.gov at any time or to 

Room PL–401 on the plaza level of the 

Nassif Building, 400 Seventh Street, 

SW., Washington, DC, between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. 

FOR FURTHER INFORMATION CONTACT: 

Kathi Ishimaru, FAA, Propulsion/ 

Mechanical Systems Branch, ANM–112, 

Transport Airplane Directorate, Aircraft 

Certification Service, 1601 Lind 

Avenue, SW., Renton, WA 98057–3356; 

telephone (425) 227–2674; facsimile 

(425) 227–1320, e-mail 

kathi.ishimaru@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

The FAA invites interested persons to 

participate in this rulemaking by 

submitting written comments, data, or 

views. We also invite comments relating 

to the economic, environmental, energy, 

or federalism impacts that might result 

from adopting the proposals in this 

document. The most helpful comments 

reference a specific portion of the 

proposal, explain the reason for any 

recommended change, and include 

supporting data. We ask that you send 

us two copies of written comments. 

We will file in the docket all 

comments we receive, as well as a 

report summarizing each substantive 

public contact with FAA personnel 

concerning this proposed rulemaking. 

The docket is available for public 

inspection before and after the comment 

closing date. If you wish to review the 

docket in person, go to the address in 

the ADDRESSES section of this preamble 

between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

You may also review the docket using 

the Internet at the web address in the 

ADDRESSES section. 

Privacy Act: Using the search function 

of our docket web site, anyone can find 

and read the comments received into 

any of our dockets, including the name 

of the individual sending the comment 

(or signing the comment on behalf of an 

association, business, labor union, etc.). 

You may review DOT’s complete 

Privacy Act Statement in the Federal 

Register published on April 11, 2000 

(65 FR 19477–78) or you may visit 

http://dms.dot.gov. 

Before acting on this proposal, we 

will consider all comments we receive 

on or before the closing date for 

comments. We will consider comments 

filed late if it is possible to do so 

without incurring expense or delay. We 

may change this proposal in light of the 

comments we receive. 

If you want the FAA to acknowledge 

receipt of your comments on this 

proposal, include with your comments 

a pre-addressed, stamped postcard on 

which the docket number appears. We 

will stamp the date on the postcard and 

mail it to you. 

Proprietary or Confidential Business 

Information 

Do not file in the docket information 

that you consider to be proprietary or 

confidential business information. Send 

or deliver this information directly to 

the person identified in the FOR FURTHER

INFORMATION CONTACT section of this 

document. You must mark the 

information that you consider 

proprietary or confidential. If you send 

the information on a disk or CD ROM, 

mark the outside of the disk or CD ROM 

and also identify electronically within 

the disk or CD ROM the specific 

information that is proprietary or 

confidential. 

Under Title 14, Code of Federal 

Regulations (14 CFR) 11.35(b), when we 

are aware of proprietary information 

filed with a comment, we do not place 

it in the docket. We hold it in a separate 

file to which the public does not have 

access, and place a note in the docket 

that we have received it. If we receive 

a request to examine or copy this 

information, we treat it as any other 

request under the Freedom of 

Information Act (5 U.S.C. 552). We 

process such a request under the DOT 

procedures found in 49 CFR part 7. 

Availability of Rulemaking Documents 

You can get an electronic copy using 

the Internet by: 

(1) Searching the Department of 

Transportation’s electronic Docket 

Management System (DMS) web page 

(http://dms.dot.gov/search); 

(2) Visiting the FAA’s Regulations and 

Policies web page at http:// 

www.faa.gov/regulations_policies; or 

(3) Accessing the Government 

Printing Office’s web page at http:// 

www.gpoaccess.gov/fr/index.html. 

You can also get a copy by sending a 

request to the Federal Aviation 

Administration, Office of Rulemaking, 

ARM–1, 800 Independence Avenue, 

SW., Washington, DC 20591, or by 

calling (202) 267–9680. Make sure to 

identify the docket number, notice 

number, or amendment number of this 

rulemaking. 

Authority for This Rulemaking 

The FAA’s authority to issue rules 

regarding aviation safety is found in 

Title 49 of the United States Code. 

Subtitle I, Section 106 describes the 

authority of the FAA Administrator. 

Subtitle VII, Aviation Programs, 


ycherry on PROD1PC64 with PROPOSALS2
Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 20925 

1FAA Inflight Aircraft Icing Plan, dated April 

1997, available in the Docket. 

2Published in the Federal Register, December 8, 

1997 (62 FR 64621). 

3Section 25.1419, Ice Protection. 

4 14 CFR 91.527, Operating in icing conditions; 

and § 135.227, Icing conditions: Operating 

limitations. 

5 14 CFR 121.629(a), Operation in icing 

conditions and § 121.341, Equipment for operations 

in icing conditions. 

6NTSB recommendation A–96–56; available in 

the Docket and on the Internet at: http:// 

www.ntsb.gov/Recs/letters/1996/A96_48_69.pdf. 

7NTSB recommendation A–98–91, available in 

the Docket and on the Internet at http:// 

www.ntsb.gov/Recs/letters/1998/A98_88_106.pdf. 

describes in more detail the scope of the 

agency’s authority. 

This rulemaking is promulgated 

under the authority described in 

Subtitle VII, Part A, Subpart III, Section 

44701, ‘‘General requirements.’’ Under 

that section, the FAA is charged with 

promoting safe flight of civil aircraft in 

air commerce by prescribing minimum 

standards required in the interest of 

safety for the design and performance of 

aircraft; regulations and minimum 

standards in the interest of safety for 

inspecting, servicing, and overhauling 

aircraft; and regulations for other 

practices, methods, and procedures the 

Administrator finds necessary for safety 

in air commerce. This regulation is 

within the scope of that authority 

because it prescribes—

• New safety standards for the design 

of transport category airplanes. 

• New safety requirements that are 

necessary for the design, production, 

operations, and maintenance of those 

airplanes, and for other practices, 

methods and procedures relating to 

those airplanes. 

Background 

On October 31, 1994, an accident 

involving an Avions de Transport 

Regional ATR 72 series airplane 

occurred in icing conditions. This 

prompted the FAA to initiate a review 

of aircraft inflight icing safety and 

determine changes that could be made 

to increase the level of safety. In May 

1996, the FAA sponsored the 

International Conference on Aircraft 

Inflight Icing where icing specialists 

recommended improvements to increase 

the level of safety of aircraft operating 

in icing conditions. The FAA reviewed 

the conference recommendations and 

developed a comprehensive multi-year 

icing plan. The FAA Inflight Aircraft 

Icing Plan (Icing Plan), dated April 

1997,1 described various activities the 

FAA was contemplating to improve 

safety when operating in icing 

conditions. In accordance with the Icing 

Plan, the FAA tasked the Aviation 

Rulemaking Advisory Committee 

(ARAC),2 through its Ice Protection 

Harmonization Working Group, to 

consider the need for ice detectors or 

other acceptable means to warn 

flightcrews of ice accretion on critical 

surfaces requiring crew action. This 

proposed rule is based on ARAC’s 

recommendations to the FAA. 

Appendix 1 defines terms used in this 

notice of proposed rulemaking (NPRM). 

A. Existing Regulations for Flight in 

Icing Conditions 

Currently, the certification regulations 

applicable to transport category 

airplanes for flight in icing conditions 

require: ‘‘the airplane must be able to 

operate safely in the continuous 

maximum and intermittent maximum 

icing conditions of appendix C.’’ 3

Parts 91, 121, and 135 contain 

regulations that apply to airplane 

operations in icing conditions. 

Operating regulations under part 91 and 

135 address limitations in icing 

conditions for airplanes operated under 

these regulations.4 Part 121 addresses 

operations in icing conditions that 

might adversely affect safety and 

installation of certain types of ice 

protection equipment and wing 

illumination equipment.5

Neither the operating regulations nor 

the certification regulations require a 

means to warn flightcrews of ice 

accretion on critical surfaces requiring 

crew action. 

B. National Transportation Safety Board 

Safety Recommendations 

The National Transportation Safety 

Board (NTSB) issued the following 

safety recommendations related to 

airframe icing that are partially 

addressed by this proposal: 

• NTSB Safety Recommendation No. 

A–96–56 6 is a result of the Avions de 

Transport Regional ATR 72 series 

airplane accident in Roselawn, Indiana 

on October 31, 1994, where 68 people 

died. The accident airplane crashed 

during a rapid descent after an 

uncommanded roll excursion while 

operating in icing conditions. The NTSB 

recommended that the FAA require a 

means for flightcrews to positively 

determine when they are in icing 

conditions that exceed the limits for 

aircraft certification. 

• NTSB Safety Recommendation No. 

A–98–91 7 is a result of the Empresa 

Brasileira de Aeronautica, S/A 

(Embraer) EMB–120 series airplane 

accident near Monroe, Michigan, on 

January 9, 1997, where 29 people died. 

The accident airplane crashed while 

operating in icing conditions. The 

flightcrew may not have activated the 

airframe ice protection system. The 

NTSB recommended that the FAA 

require manufacturers and operators to 

revise their manuals and training to 

emphasize that leading edge deicing 

boots should be activated as soon as the 

airplane enters icing conditions. 

C. Authorities 

1. Federal Aviation Administration 

Title 14 CFR part 25 contains the U.S. 

airworthiness standards for type 

certification of transport category 

airplanes. These standards apply to 

airplanes manufactured within the U.S. 

and to airplanes manufactured in other 

countries and imported to the U.S. 

under a bilateral airworthiness 

agreement. 

2. Joint Aviation Authorities 

The Joint Airworthiness Requirements 

(JAR)–25 contain the European 

airworthiness standards for type 

certification of transport category 

airplanes. Thirty-seven European 

countries accept airplanes type 

certificated to JAR–25 standards, 

including airplanes manufactured in the 

U.S. that are type certificated to JAR–25 

standards for export to Europe. 

3. European Aviation Safety Agency 

A new aviation regulatory body, the 

European Aviation Safety Agency 

(EASA), was established by the 

European community to develop 

standards to ensure the highest level of 

safety and environmental protection, 

oversee their uniform application, and 

promote them internationally. The 

EASA formally became operational for 

certification of aircraft, engines, parts, 

and appliances on September 28, 2003. 

The EASA will eventually absorb all 

functions and activities of the Joint 

Aviation Authorities, including its 

efforts to harmonize EASA’s 

airworthiness certification regulations 

with those of the U.S. 

The JAR–25 standards have been 

incorporated into EASA’s ‘‘Certification 

Specifications for Large Aeroplanes,’’

(CS)–25, in similar if not identical 

language. The EASA’s CS–25 became 

effective October 17, 2003. 

D. Harmonization of U.S. Standards 

With Those of Other Countries 

The airworthiness standards proposed 

in this NPRM were developed before 

EASA began operations. They were 

developed in coordination with the 

Joint Aviation Authorities (JAA), United 

Kingdom Civil Aviation Authority, and 

Transport Canada. 


ycherry on PROD1PC64 with PROPOSALS2
20926 Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 

E. Related Rulemaking Activity 

1. Docket No. 2005–22840; Notice No. 

05–10 

The proposed rulemaking would 

amend part 25 by adding specific 

requirements for airplane performance 

and handling qualities for flight in icing 

conditions. Further, the proposal 

amends § 25.1419 to address 

certification approval for flight in icing 

conditions for airplanes without ice 

protection features. Those proposed 

changes do not impact this rulemaking. 

However, this rulemaking may result in 

minor conforming changes to the 

airplane performance and handling 

qualities for flight in icing conditions 

rules. 

2. ARAC Ice Protection Harmonization 

Working Group Recommendations 

The ARAC has submitted additional 

rulemaking recommendations to the 

FAA to improve the safety of operations 

in icing conditions: 

• Part 121 recommendations to 

address activation of ice protection 

systems. 

• Part 121 recommendations to 

require certain airplanes to exit icing 

conditions. 

• Part 25 and 33 recommendations to 

address operations in supercooled large 

droplet, mixed phase, and glaciated 

icing conditions. 

The recommendations may lead to 

future rulemaking, but do not directly 

impact this NPRM. 

F. Advisory Material 

In addition to this NPRM, the FAA is 

developing Advisory Circular (AC) 

25.1419–2x, Compliance with the Ice 

Protection Requirements of 

§§ 25.1419(e), (f), (g), and (h). This 

proposed AC would provide guidance 

material for one acceptable means, but 

not the only means, of demonstrating 

compliance with this proposed rule. 

The proposed AC will be posted on 

‘‘Aircraft Certification Draft Documents 

Open for Comment’’ Web site, http:// 

www.faa.gov/aircraft/draft_docs, on the 

same date this NPRM is published in 

the Federal Register The date comments 

are due is indicated on that Web site. 

Discussion of the Proposal 

A. Safety Concern 

The ARAC Ice Protection 

Harmonization Working Group 

reviewed icing events and found 

accidents and incidents where the 

flightcrew was either completely 

unaware of ice accretion on the 

airframe, or was aware of ice accretion, 

but judged that it was not significant 

enough to warrant operation of the 

airframe ice protection system (IPS). 

The ARAC Ice Protection 

Harmonization Working Group 

concluded and recommended to the 

FAA that flightcrews must be provided 

with a clear means to know when to 

activate the IPS. 

B. Means To Address the Safety 

Concern 

The FAA has issued airworthiness 

directives to address the safety concern 

of when to activate the IPS on certain 

airplanes. These airworthiness 

directives require activation of 

pneumatic deicing boots at the first 

signs of ice accretion on the airplane. 

This requirement relieves the pilot of 

the responsibility for determining if the 

amount of ice accumulated on the wing 

warrants activation of the IPS. However, 

activation of the deicing boots is still 

subject to the flightcrew’s observation of 

ice accretions, and such observations 

can be difficult during times of high 

workload, operations at night, or when 

clear ice has accumulated. Also, the 

difficulties of observing ice accretions 

are applicable to any IPS that relies on 

the flightcrew’s observations for 

activating the system, not just 

pneumatic deicing boots. 

The ARAC Ice Protection 

Harmonization Working Group 

concluded that installing a device to 

alert the flightcrew to activate the IPS 

would be an improved means to address 

these situations for future airplanes. A 

primary ice detection system would be 

one acceptable means. A primary ice 

detection system typically consists of 

two independent detectors. It could 

either automatically activate the IPS, or 

provide an indication to the flightcrew 

when the system must be activated 

manually. An advisory ice detection 

system, in conjunction with 

substantiated visual cues, would also be 

an acceptable means. The acceptability 

is contingent upon: 

• An advisory ice detection system 

that annunciates when icing conditions 

exist or when the substantiated visual 

cues are present. 

• The substantiated visual cues rely 

on the flightcrew’s observation of the 

first sign of ice accretion on the airplane 

and do not depend on the pilot 

determining the thickness of the 

accretion. 

• The flightcrew activates the ice 

protection system when they observe 

the ice accretion or when the ice 

detector annunciates, whichever occurs 

first. 

An advisory ice detection system 

typically consists of one detector. Such 

a system does not have sufficient 

reliability to be the primary means of 

determining when the IPS must be 

activated. However, the advisory ice 

detection system would provide a much 

higher level of safety than visual cues 

alone and would mitigate the effects of 

human sensory limitations and 

inadequate attention due to workload. 

The ARAC Ice Protection 

Harmonization Working Group also 

concluded that an acceptable alternative 

to requiring an ice detector would be to 

require operating the IPS whenever the 

airplane is operating in conditions 

conducive to airframe icing. In this case, 

the flightcrew would activate the IPS in 

response to a specific air temperature 

threshold and the presence of visible 

moisture. Because ambient temperature 

is indicated by flightdeck instruments 

and the flightcrew can readily observe 

visible moisture, deciding when to 

initiate the system would require little 

increased effort by the flightcrew. 

The IPS activation method should be 

applicable during all phases of flight, 

unless it can be shown that the IPS need 

not be activated during certain phases of 

flight. For example, if the IPS is not 

operated during takeoff until after the 

second segment climb, then the 

applicant must substantiate that the 

airplane can operate safely with ice 

accretions that could form prior to this 

point. 

The FAA concurs with the safety 

concern that flightcrews must be 

provided with a clear means to know 

when to activate the IPS. To ensure 

timely activation of the IPS, the 

proposed § 25.1419(e) requires one of 

the three acceptable methods 

recommended by the ARAC Ice 

Protection Harmonization Working 

Group: a primary ice detector, visual 

cues and an advisory ice detector, or 

operation based on temperature and 

visible moisture. 

Specifically, proposed § 25.1419(e) 

requires one of the following methods of 

icing detection and activation of the 

airframe IPS: 

(1) A primary ice detection system 

that automatically activates or alerts the 

flightcrew to activate the airframe IPS; 

or 

(2) A definition of visual cues for 

recognition of the first sign of ice 

accretion on a specified surface 

combined with an advisory ice 

detection system that alerts the 

flightcrew to activate the airframe IPS; 

or 

(3) Identification of conditions 

conducive to airframe icing as defined 

by an appropriate static or total air 

temperature and visible moisture for use 

by the flightcrew to activate the airframe 

IPS. 


ycherry on PROD1PC64 with PROPOSALS2
Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 20927 

Proposed § 25.1419(f) requires the 

activation method be applicable to all 

phases of flight unless it can be shown 

that the ice protection system need not 

be operated during specific phases of 

flight. Proposed § 25.1419(h) requires 

that the procedures for operating the ice 

protection system be included in the 

Airplane Flight Manual. 

C. Flightcrew Workload 

The FAA is concerned with the 

flightcrew workload created if an IPS 

must be manually cycled. Manual 

operation of the IPS could be a 

distraction during the approach and 

landing phases of flight which typically 

involve higher pilot workloads. During 

these critical phases of flight, 

flightcrews have less time to devote to 

managing the airplane ice accretions. 

An IPS that is automatically cycled or 

operates on a continuous basis (for 

example, an anti-icing system) does not 

create this additional workload and, 

therefore, is not a concern. Section 

25.1419(g) of this proposed rule 

alleviates the workload concerns by 

requiring airplanes to be equipped with 

an IPS that would operate in a cyclical 

manner. This would include a system 

that would automatically cycle the IPS 

or an ice detection system that would 

alert the flightcrew whenever IPS 

cycling is necessary. 

D. Applicability of the Proposed Rule 

A review of icing events found 

discriminating design factors, such as 

wing chord length or airplane weight, 

significantly influence the risk of icing 

accidents and incidents. The FAA and 

the ARAC Ice Protection Harmonization 

Working Group, however, determined 

that a certification rule dealing with ice 

detectors should not be limited to a 

specific group of airplanes because of 

past performance. Since future airplane 

designs could change, a similar safety 

record might not be achieved. Relying 

solely on past performance data for 

future airplane designs would not be 

prudent. Therefore, the proposed rule is 

applicable to all part 25 airplanes. 

E. Technology 

The FAA and ARAC Ice Protection 

Harmonization Working Group 

reviewed the current state of ice 

detector technology and found that it 

provides a viable means of compliance 

with the proposed rule. Several methods 

exist that can reliably alert the 

flightcrew to activate the IPS. This 

technology has been certificated for use 

on airplanes to alert or advise the pilot 

of ice or as the primary means of 

determining when the IPS should be 

activated. 

One ice detection system that is 

commercially available indicates when 

a deicing IPS should be initially 

activated and subsequently activated if 

the IPS operates in a cyclical manner. 

This system has sensors installed on the 

protected airplane surfaces that sense 

the accretion of ice sufficient to warrant 

cycling of a deicing system. Other ice 

detection systems are capable of sensing 

the rate of ice accretion and are able to 

indicate when a deicing IPS should be 

cycled based on ice accretion since the 

preceding cycling of the system. 

F. Differences From the ARAC 

Recommendation 

The ARAC Ice Protection 

Harmonization Working Group 

recommended identification of 

conditions conducive to airframe icing 

as one method of icing detection and 

activation of the airframe ice protection 

system. However, identification of 

conditions conducive to airframe icing 

is only a method of icing detection and 

not of activation. Therefore, the FAA 

revised the ARAC recommendation by 

clarifying that identification of 

conditions conducive to airframe icing 

is to be used for both icing detection 

and activation of the IPS. The revision 

is considered a minor change and does 

not affect the intent of the ARAC 

recommendation. 

Rulemaking Notices and Analyses 

Paperwork Reduction Act 

The Paperwork Reduction Act of 1995 

(44 U.S.C. 3507(d)) requires that the 

FAA consider the impact of paperwork 

and other information collection 

burdens imposed on the public. An 

Airplane Flight Manual is required by 

existing part 25 regulations and must 

contain information that is necessary for 

safe operation of the airplane. The 

proposed rule requires that the 

procedures for operating the ice 

protection system be included in the 

Airplane Flight Manual. The proposed 

rule is applicable to future certification 

programs and does not require changes 

to existing Airplane Flight Manuals. 

Therefore, we have determined that 

there are no new information collection 

requirements associated with this 

proposed rule. 

International Compatibility 

In keeping with U.S. obligations 

under the Convention on International 

Civil Aviation, it is FAA policy to 

comply with International Civil 

Aviation Organization (ICAO) Standards 

and Recommended Practices to the 

maximum extent practicable. The FAA 

determined that there are no ICAO 

Standards and Recommended Practices 

that correspond to these proposed 

regulations. 

Executive Order 12866 and DOT 

Regulatory Policies and Procedures 

Executive Order 12866, ‘‘Regulatory 

Planning and Review,’’ dated September 

30, 1993 (58 FR 51736) directs the FAA 

to assess both the costs and the benefits 

of a regulatory change. We are not 

allowed to propose or adopt a regulation 

unless we make a reasoned 

determination that the benefits of the 

intended regulation justify the costs. 

Our assessment of this rulemaking 

indicates that its economic impact is 

minimal. Because the costs and benefits 

of this action do not make it a 

‘‘significant regulatory action’’ as 

defined in the Order, we have not 

prepared a ‘‘regulatory evaluation,’’

which is the written cost/benefit 

analysis ordinarily required for all 

rulemaking under the DOT Regulatory 

Policies and Procedures. We do not 

need to do a full evaluation where the 

economic impact of a rule is minimal. 

Economic Evaluation, Regulatory 

Flexibility Determination, Trade Impact 

Assessment, and Unfunded Mandates 

Assessment 

Changes to Federal regulations must 

undergo several economic analyses. 

First, Executive Order 12866 directs that 

each Federal agency shall propose or 

adopt a regulation only upon a reasoned 

determination that the benefits of the 

intended regulation justify its costs. 

Second, the Regulatory Flexibility Act 

of 1980 (Pub. L. 96–354) requires 

agencies to analyze the economic 

impact of regulatory changes on small 

entities. Third, the Trade Agreements 

Act (Pub. L. 96–39) prohibits agencies 

from setting standards that create 

unnecessary obstacles to the foreign 

commerce of the United States. In 

developing U.S. standards, the Trade 

Act requires agencies to consider 

international standards and, where 

appropriate, that they be the basis of 

U.S. standards. Fourth, the Unfunded 

Mandates Reform Act of 1995 (Pub. L. 

104–4) requires agencies to prepare a 

written assessment of the costs, benefits, 

and other effects of proposed or final 

rules that include a Federal mandate 

likely to result in the expenditure by 

State, local, or tribal governments, in the 

aggregate, or by the private sector, of 

$100 million or more annually (adjusted 

for inflation with base year of 1995). 

This portion of the preamble 

summarizes the FAA’s analysis of the 

economic impacts of this proposed rule. 

Department of Transportation Order 

DOT 2100.5 prescribes policies and 


ycherry on PROD1PC64 with PROPOSALS2
20928 Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 

8 ‘‘APO–300 Guidance on Labor Costs’’, May 

2006. 

procedures for simplification, analysis, 

and review of regulations. If the 

expected cost impact is so minimal that 

a proposed or final rule does not 

warrant a full evaluation, this order 

permits that a statement to that effect 

and the basis for it be included in the 

preamble if a full regulatory evaluation 

of the cost and benefits is not prepared. 

Such a determination has been made for 

this proposed rule. The reasoning for 

this determination follows. 

An assessment has been conducted of 

the economic cost impact of the 

proposed rule amending § 25.1419 of 

Title 14 of the Code of Federal 

Regulations (14 CFR) part 25. The FAA 

proposes to change the regulations 

applicable to transport category 

airplanes certificated for flight in icing 

conditions. This proposal would require 

newly certificated part 25 transport 

category airplanes certificated for flight 

in icing to have one of the following 

methods to detect ice and activate the 

airframe IPS: 

• A primary ice detection system, 

automatic or manual; 

• The definition of visual cues for 

recognition of the first sign of ice 

accretion on a specified surface 

combined with an advisory ice 

detection system that alerts the 

flightcrew; or 

• The identification of icing 

conditions by an appropriate static or 

total air temperature and visible 

moisture cues. 

This proposal is the result of 

information gathered from a review of 

historical icing accidents and incidents. 

This proposal is intended to improve 

the level of safety when part 25 

airplanes are operated in icing 

conditions. 

A. Cost Discussion 

1. Major Assumptions. This 

evaluation makes the following 

assumptions: 

• We used a $50 hourly rate for a 

mechanic/technician and a $75 hourly 

rate for an engineer working for an 

airplane manufacturer or modifier.8

• Whenever various compliance 

options are available to the 

manufacturers, we chose the least costly 

option in our analysis. 

Other data and derived assumptions 

are discussed in the following sections 

on costs and benefits. 

2. Industry Estimate of Costs. This 

section discusses the costs to require 

part 25 manufacturers to include a 

method of ice detection for newly 

certificated transport category airplanes. 

This proposal would require 

manufacturers of part 25 airplanes to 

provide the flightcrew with an effective 

method of ice detection. Such a method 

would provide a means, via an ice 

detection system (IDS), to alert the 

flightcrew of icing conditions and 

enable timely activation of the airframe 

ice protection system (IPS) for the initial 

and any subsequent cycles. 

The requirements for ice detection 

and activation of the airframe IPS are 

applicable to all phases of flight, unless 

it can be shown that the IPS need not 

be operated during specific phases of 

flight. If the IPS operates in a cyclical 

manner, it must either include a system 

that automatically cycles the IPS, or 

there must be a method that alerts the 

flightcrew each time the IPS must be 

cycled. In addition, this proposal would 

require that the Airplane Flight Manual 

contain procedures for activation and 

operation of the IPS. 

The Goodrich Corporation and the 

ARAC Ice Protection Harmonization 

Working Group provided us with 

manufacturer cost estimates for System 

Design, System Qualification, Hardware, 

Installation, and Maintenance. 

3. Section-by-Section Estimate of 

Costs. The cost estimates, by section, are 

discussed next. 

§ 25.1419(e) 

This section proposes three 

alternative methods of ice detection: 

• A primary IDS, automatic or 

manual; or 

• The definition of visual cues for 

recognition of the first sign of ice 

accretion on a specified surface 

combined with an advisory ice 

detection system that alerts the 

flightcrew; or 

• The identification of icing 

conditions by an appropriate static or 

total air temperature and visible 

moisture cues. 

Any of the three proposed ice 

detection methods would enable timely 

activation of the airframe IPS and satisfy 

the intent of this proposal. 

The first method of ice detection is 

the use of a primary IDS. A primary IDS 

usually has two ice detectors. The cost 

of an ice detector used in this analysis 

is based on the Goodrich Corporation’s 

average price of $6,000 per ice detector 

for a production airplane. Assuming the 

primary IDS has two ice detectors, we 

estimate the average cost for a primary 

IDS to be about $485,000 per 

certification, $12,000 ($6,000 × 2) for the 

hardware and $2,500 for the 

installation, or $14,500 ($12,000 + 

$2,500) per airplane. Table 1 shows a 

detailed breakout of these cost 

estimates. 

TABLE 1.—COSTS FOR § 25.1419(e)(1)—PRIMARY ICE DETECTION SYSTEM

Manufacturer non-recurring costs (per aircraft group/type) 2006$ Hours Hourly rate Additional cost Cost 

System Design: 

System architecture/Integration ................................................................ 3,000 $75 ........................ $225,000 

Ice detector positioning ............................................................................ 300 75 ........................ 22,500 

Procedures for AFM, AOM/FCOM & MMEL ............................................ 200 75 ........................ 15,000 

System Qualification/certification: 

Ice detector qualification ........................................................................... 300 75 ........................ 22,500 

Ice detection system certification ............................................................. 600 75 ........................ 45,000 

Flight tests ................................................................................................ 400 75 $100,000 130,000 

Installation Design: 

Installation drawings ................................................................................. 500 50 ........................ 25,000 

Total ................................................................................................... 5,300 ........................ ........................ 485,000 

Costs (per airplane): 

Hardware (Primary Ice Detection System) ............................................... ........................ ........................ 12,000 12,000 

Installation ................................................................................................. 50 50 ........................ 2,500 

Additional weight is 5–10 kg .................................................................... ........................ ........................ ........................ 0 


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Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 20929 

TABLE 1.—COSTS FOR § 25.1419(e)(1)—PRIMARY ICE DETECTION SYSTEM—Continued 

Manufacturer non-recurring costs (per aircraft group/type) 2006$ Hours Hourly rate Additional cost Cost 

Total ................................................................................................... ........................ ........................ ........................ 14,500 

The second method of ice detection is 

the use of an advisory IDS along with 

visual cues. The major difference 

between a primary and an advisory IDS 

is that the primary IDS is the principal 

means to determine when the airframe 

IPS should be activated. In contrast, an 

advisory IDS is a backup to the 

flightcrew and has only one ice detector. 

The average cost for an advisory IDS is 

estimated to be $447,500 per 

certification, $6,000 for the hardware 

and $1,250 for the installation, or $7,250 

($6,000 + $1,250) per airplane. Table 2 

shows a detailed breakout of these cost 

estimates. 

TABLE 2.—COSTS FOR § 25.1419(e)(2)—ADVISORY ICE DETECTION SYSTEM AND VISUAL CUES

Manufacturer non-recurring costs (per aircraft group/type) 2006$ Hours Hourly rate Additional cost Cost 

System Design: 

System architecture/Integration ................................................................ 2,500 $75 ........................ $187,500 

Ice detector positioning ............................................................................ 200 75 ........................ 15,000 

Visual cue determination/design .............................................................. 200 75 ........................ 15,000 

Procedures for AFM, AOM/FCOM & MMEL ............................................ 200 75 ........................ 15,000 

System Qualification/certification: 

Ice detection qualification ......................................................................... 300 75 ........................ 22,500 

Visual cue substantiation .......................................................................... 200 75 ........................ 15,000 

Ice detection system certification ............................................................. 300 75 ........................ 22,500 

Flight tests ................................................................................................ 400 75 $100,000 130,000 

Installation Design: 

Installation drawings ................................................................................. 500 50 ........................ 25,000 

Total ................................................................................................... 4,800 ........................ ........................ 447,500 

Costs (per airplane): 

Hardware (Advisory Ice Detection System) ............................................. ........................ ........................ 6,000 6,000 

Installation ................................................................................................. 25 50 ........................ 1,250 

Additional weight is 5–10 kg .................................................................... ........................ ........................ ........................ 0 

Total ................................................................................................... ........................ ........................ ........................ 7,250 

The third method of ice detection is 

a definition of conditions conducive to 

airframe icing that would be used by the 

flightcrew to activate the airframe IPS. 

This definition would be included in 

the Airplane Flight Manual. There are 

no costs imposed on the airplane 

manufacturers with this option. 

A summary of the costs for each 

alternative is shown in Table 3: 

TABLE 3.—COST SUMMARY—§ 25.1419(e) 

§ 25.1419 Alternatives 

Costs 

Per 

certification Per airplane 

(e)(1) Primary IDS ................................................................................................................................................... $485,000 $14,500 

(e)(2) Advisory IDS and Visual Cues ...................................................................................................................... 447,500 7,250 

(e)(3) Temperature and Moisture ............................................................................................................................ 0 0 

The least cost alternative is to activate 

the existing airframe IPS whenever the 

airplane is operating in conditions 

conducive to airframe icing based on a 

specific air temperature threshold and 

the presence of visible moisture. Since 

there are no additional certification or 

production costs to manufacturers by 

complying with § 25.1419(e)(3) through 

this alternative, we have determined 

there are no costs associated with 

compliance with § 25.1419(e). 

We are aware some manufacturers 

may choose to install more complex 

systems ((e)(1) or (e)(2)), and want to 

note these more complex systems are 

acceptable alternatives to (e)(3). 

§ 25.1419(f). Section 25.1419(f) 

describes the applicability of the 

proposed rule, so there are no additional 

costs associated with this section. 

§ 25.1419(g). After the initial 

operation of the IPS, § 25.1419(g) 

provides alternatives the manufacturer 

must provide to the operator for safe 

flight. These alternatives are: 

• The IPS must operate continuously, 

or 

• The airplane must be equipped 

with a system that automatically cycles 

the IPS, or 

• An ice detection system must be 

provided to alert the flightcrew each 

time the IPS must be cycled. 

Section 25.1419(g) applies to 

airplanes with either a thermal anti-ice 

protection system or an IPS that 

operates in a cyclical manner. Thermal 

anti-ice protection systems operate 

continuously while deicing systems 

usually operate cyclically. 


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20930 Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 

9Type Certification Data Sheet No. A22CE. 

Section 25.1419(g)(1) applies 

primarily to thermal anti-ice protection 

systems. Thermal anti-ice protection 

systems typically use heat or freezing 

point depressant fluids to keep 

protected surfaces of the airplane free of 

ice accretions. 

No additional manufacturing costs are 

associated with § 25.1419(g)(1) because 

once a thermal anti-ice protection 

system is activated, it is capable of 

operating continuously. 

Section 25.1419(g)(2) and (3) applies 

to IPS that operate in a cyclical manner. 

Past delivery history has shown that 

about 97% of U.S manufactured part 25 

airplanes delivered have thermal antiice protection systems and 3% have 

deicing IPSs that operate in a cyclical 

manner. Cessna is the only U.S. 

manufacturer that currently delivers 

new part 25 certificated airplanes with 

an IPS that operates in a cyclical 

manner. Those airplanes delivered with 

an IPS that operates in a cyclical 

manner were certificated in September 

1971.9 Later variants from that 

September 1971 type certificate and all 

later part 25 new Cessna certifications 

have thermal anti-ice protection systems 

that operate continuously. We believe 

the trend for new part 25 aircraft 

certifications is toward thermal anti-ice 

protection systems that operate 

continuously. Because of the trend of 

part 25 manufacturers to install thermal 

anti-ice protection systems in their 

newly certificated part 25 airplanes, we 

believe there are no costs imposed on 

the airplane manufacturers by 

§ 25.1419(g). 

We seek comments from U.S. 

manufacturers on their plans to produce 

a newly part 25 certificated aircraft with 

deicing systems that operate cyclically 

and the associated certification costs. 

§ 25.1419(h). Future Airplane Flight 

Manuals can readily be prepared to 

include appropriate icing procedures for 

future certificated air transport category 

airplanes. Thus minimal costs are 

associated with § 25.1419(h). 

4. Conclusion. Since this final rule 

has minimal costs, a full regulatory 

evaluation was not prepared. The FAA 

requests comments with supporting 

justification about our determination of 

a minimal impact from this proposal. 

Regulatory Flexibility Determination 

The Regulatory Flexibility Act of 1980 

(Pub. L. 96–354) (RFA) establishes ‘‘as a 

principle of regulatory issuance that 

agencies shall endeavor, consistent with 

the objectives of the rule and of 

applicable statutes, to fit regulatory and 

informational requirements to the scale 

of the businesses, organizations, and 

governmental jurisdictions subject to 

regulation. To achieve this principle, 

agencies are required to solicit and 

consider flexible regulatory proposals 

and to explain the rationale for their 

actions to assure that such proposals are 

given serious consideration.’’ The RFA 

covers a wide-range of small entities, 

including small businesses, not-forprofit organizations, and small 

governmental jurisdictions. 

Agencies must perform a review to 

determine whether a rule will have a 

significant economic impact on a 

substantial number of small entities. If 

the agency determines that it will, the 

agency must prepare a regulatory 

flexibility analysis as described in the 

RFA. 

However, if an agency determines that 

a rule is not expected to have a 

significant economic impact on a 

substantial number of small entities, 

section 605(b) of the RFA provides that 

the head of the agency may so certify 

and a regulatory flexibility analysis is 

not required. The certification must 

include a statement providing the 

factual basis for this determination, and 

the reasoning should be clear. 

All United States transport category 

aircraft manufacturers exceed the Small 

Business Administration small-entity 

criteria of 1,500 employees. 

Therefore, the FAA certifies that this 

proposed rule would not have a 

significant economic impact on a 

substantial number of small entities. 

The FAA solicits comments regarding 

this determination. 

Trade Impact Assessment 

The Trade Agreements Act of 1979 

(Pub. L. 96–39) prohibits Federal 

agencies from establishing any 

standards or engaging in related 

activities that create unnecessary 

obstacles to the foreign commerce of the 

United States. Legitimate domestic 

objectives, such as safety, are not 

considered unnecessary obstacles. The 

statute also requires consideration of 

international standards and, where 

appropriate, that they be the basis for 

U.S. standards. The FAA has assessed 

the potential effect of this proposed rule 

and has determined that it would 

impose the same costs on domestic and 

international entities and thus has a 

neutral trade impact. 

Unfunded Mandates Assessment 

Title II of the Unfunded Mandates 

Reform Act of 1995 (Pub. L. 104–4) 

requires each Federal agency to prepare 

a written statement assessing the effects 

of any Federal mandate in a proposed or 

final agency rule that may result in an 

expenditure of $100 million or more 

(adjusted annually for inflation with the 

base year 1995) in any one year by State, 

local, and tribal governments, in the 

aggregate, or by the private sector; such 

a mandate is deemed to be a ‘‘significant 

regulatory action.’’ The FAA currently 

uses an inflation-adjusted value of 

$128.1 million in lieu of $100 million. 

This proposed rule does not contain 

such a mandate. 

Executive Order 13132, Federalism 

The FAA has analyzed this proposed 

rule under the principles and criteria of 

Executive Order 13132, Federalism. We 

determined that this action would not 

have a substantial direct effect on the 

States, on the relationship between the 

national Government and the States, or 

on the distribution of power and 

responsibilities among the various 

levels of government, and therefore 

would not have federalism implications. 

Regulations Affecting Intrastate 

Aviation in Alaska 

Section 1205 of the FAA 

Reauthorization Act of 1996 (110 Stat. 

3213) requires the Administrator, when 

modifying regulations in 14 CFR in a 

manner affecting intrastate aviation in 

Alaska, to consider the extent to which 

Alaska is not served by transportation 

modes other than aviation, and to 

establish such regulatory distinctions as 

he or she considers appropriate. 

Because this proposed rule would apply 

to the certification of future designs of 

transport category airplanes and their 

subsequent operation, it could, if 

adopted, affect intrastate aviation in 

Alaska. The FAA therefore specifically 

requests comments on whether there is 

justification for applying the proposed 

rule differently in intrastate operations 

in Alaska. 

Plain English 

Executive Order 12866 (58 FR 51735, 

Oct. 4, 1993) requires each agency to 

write regulations that are simple and 

easy to understand. We invite your 

comments on how to make these 

proposed regulations easier to 

understand, including answers to 

questions such as the following: 

• Are the requirements in the 

proposed regulations clearly stated? 

• Do the proposed regulations contain 

unnecessary technical language or 

jargon that interferes with their clarity? 

• Would the proposed regulations be 

easier to understand if they were 

divided into more (but shorter) sections? 

• Is the description in the preamble 

helpful in understanding the proposed 

regulations? 


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Federal Register / Vol. 72, No. 80 / Thursday, April 26, 2007 / Proposed Rules 20931 

Please send your comments to the 

address specified in the ADDRESSES

section. 

Environmental Analysis 

FAA Order 1050.1E identifies FAA 

actions that are categorically excluded 

from preparation of an environmental 

assessment or environmental impact 

statement under the National 

Environmental Policy Act in the 

absence of extraordinary circumstances. 

The FAA has determined that this 

proposed rulemaking action qualifies for 

the categorical exclusion identified in 

paragraph 4(j). 

Regulations That Significantly Affect 

Energy Supply, Distribution, or Use 

The FAA has analyzed this NPRM 

under Executive Order 13211, Actions 

Concerning Regulations that 

Significantly Affect Energy Supply, 

Distribution, or Use (May 18, 2001). We 

have determined that it is not a 

‘‘significant energy action’’ under the 

executive order because it is not a 

‘‘significant regulatory action’’ under 

Executive Order 12866, and it is not 

likely to have a significant adverse effect 

on the supply, distribution, or use of 

energy. 

Appendix 1—Definition of Terms Used in 

This NPRM 

For the purposes of this NPRM, the 

following definitions are applicable. These 

definitions of terms are intended for use only 

with this NPRM: 

a. Advisory ice detection system: An 

advisory system annunciates the presence of 

icing conditions or ice accretion. The 

advisory ice detection system provides 

information advising the flightcrew of the 

presence of ice accretion or icing conditions. 

It can only be used in conjunction with other 

means (most commonly, visual observation 

by the flightcrew) to determine the need for, 

or timing of, activating the anti-icing or 

deicing system. The flightcrew is responsible 

for monitoring the icing conditions or ice 

accretion as defined in the AFM (typically 

using total air temperature and visible 

moisture criteria or visible ice accretion) and 

activating the anti-icing or deicing system(s). 

b. Airframe icing: Airframe icing is ice 

accretions on portions of the airplane, with 

the exception of the propulsion system, on 

which supercooled liquid droplets may 

impinge. 

c. Anti-icing: Anti-icing is the prevention 

of ice accretions on a protected surface, 

either: 

• By evaporating the impinging water; or 

• By allowing it to run back and off the 

surface or freeze on non-critical areas. 

d. Automatic cycling mode: An automatic 

cycling mode is a mode of operation of the 

airframe deicing system that provides 

repetitive cycles of the system without the 

need for the pilot to select each cycle. This 

is generally done with a timer, and there may 

be more than one timing mode. 

e. Deicing: Deicing is the removal or the 

process of removal of an ice accretion after 

it has formed on a surface. 

f. Ice Protection System: An ice protection 

system (IPS) is a system that protects certain 

critical airframe parts from ice accretion. To 

be an approved system, it must satisfy the 

requirements of § 25.1419. 

g. Primary ice detection system: A primary 

ice detection system is used to determine 

when the IPS must be activated. The system 

annunciates the presence of ice accretion or 

icing conditions, and may also provide 

information to other aircraft systems. A 

primary automatic system automatically 

activates the anti-icing or deicing IPS. With 

a primary manual system, the flightcrew 

activates the anti-icing or deicing IPS upon 

indication from the primary ice detection 

system. 

h. Static air temperature: The air 

temperature as would be measured by a 

temperature sensor not in motion with 

respect to that air. This temperature is also 

referred to in other documents as ‘‘outside air 

temperature,’’ ‘‘true outside temperature,’’ or 

‘‘ambient temperature.’’

List of Subjects in 14 CFR Part 25 

Aircraft, Aviation safety, Reporting 

and recordkeeping requirements, Safety, 

Transportation. 

The Proposed Amendment 

In consideration of the foregoing, the 

Federal Aviation Administration 

proposes to amend part 25 of Title 14, 

Code of Federal Regulations, as follows: 

PART 25—AIRWORTHINESS 

STANDARDS: TRANSPORT 

CATEGORY AIRPLANES 

1. The authority citation for part 25 

continues to read as follows: 

Authority: 49 U.S.C. 106(g), 40113, 44701, 

44702 and 44704. 

2. Amend § 25.1419 by adding new 

paragraphs (e), (f), (g), and (h) to read as 

follows: 

§ 25.1419 Ice Protection. 

* * * * * 

(e) One of the following methods of 

icing detection and activation of the 

airframe ice protection system must be 

provided: 

(1) A primary ice detection system 

that automatically activates or alerts the 

flightcrew to activate the airframe ice 

protection system; 

(2) A definition of visual cues for 

recognition of the first sign of ice 

accretion on a specified surface 

combined with an advisory ice 

detection system that alerts the 

flightcrew to activate the airframe ice 

protection system; or 

(3) Identification of conditions 

conducive to airframe icing as defined 

by an appropriate static or total air 

temperature and visible moisture for use 

by the flightcrew to activate the airframe 

ice protection system. 

(f) Unless the applicant shows that the 

ice protection system need not be 

operated during specific phases of 

flight, the requirements of paragraph (e) 

are applicable to all phases of flight. 

(g) After the initial activation of the 

ice protection system—

(1) The ice protection system must 

operate continuously; 

(2) The airplane must be equipped 

with a system that automatically cycles 

the ice protection system; or 

(3) An ice detection system must be 

provided to alert the flightcrew each 

time the ice protection system must be 

cycled. 

(h) Procedures for operation of the ice 

protection system must be established 

and documented in the Airplane Flight 

Manual. 

Issued in Washington, DC, on April 11, 

2007. 

John J. Hickey, 

Director, Aircraft Certification Service. 

[FR Doc. E7–7944 Filed 4–25–07; 8:45 am] 

BILLING CODE 4910–13–P 


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