Federal Register / Vol. 80, No. 213 / Wednesday, November 4, 2015 / Proposed Rules 68281 

TABLE A—LAMP-AND-BALLAST PAIRINGS AND FREQUENCY ADJUSTMENT FACTORS—Continued 

Ballast type 

Lamp type Frequency adjustment factor (b) 

Lamp diameter and base Nominal lamp 

wattage Low-frequency High-frequency 

Ballasts that operate straight-shaped lamps 

(commonly referred to as 4-foot miniature 

bipin standard output lamps) with miniature 

bipin bases and a nominal length between 

45 and 48 inches.

T5 SO Mini-BP (Data Sheet 

60081–IEC–6640–5) *.

28 0.95 1.0 

Ballasts that operate straight-shaped lamps 

(commonly referred to as 4-foot miniature 

bipin high output lamps) with miniature bipin 

bases and a nominal length between 45 

and 48 inches.

T5 HO Mini-BP (Data Sheet 

60081–IEC–6840–4) *.

54 0.95 1.0 

Sign ballasts that operate rapid-start lamps 

(commonly referred to as 8-foot high output 

lamps) with recessed double contact bases 

and a nominal overall length of 96 inches.

T8 HO RDC (Data Sheet 7881– 

ANSI–1501–1) *.

86 0.92 1.0 

T12 HO RDC (Data Sheet 7881– 

ANSI–1019–1) *.

110 † 0.94 1.0 

MBP, Mini-BP, RDC, and SP represent medium bipin, miniature bipin, recessed double contact, and single pin, respectively. 

A ballast must be tested with only one lamp type based on the ballast type description and lamp diameter it is designed and marketed to operate. 

* Data Sheet corresponds to ANSI C78.81, ANSI C78.901, or IEC 60081 page number (incorporated by reference; see § 430.3). 

** No ANSI or IEC Data Sheet exists for 34 W T12 MBP U-shaped lamps. For ballasts designed to operate only T12 2-foot U-shaped lamps 

with MBP bases and a nominal overall length between 22 and 25 inches, manufacturers should select a T12 U-shaped lamp designed and marketed as having a nominal wattage of 34 W. 

† Lamp type is commonly marketed as 110 W, however the ANSI C78.81 Data Sheet (incorporated by reference; see § 430.3) lists nominal 

wattage of 113 W. Specifications for operation at 0.800 amperes (A) should be used for testing. 

* * * * * 

[FR Doc. 2015–28077 Filed 11–3–15; 8:45 am] 

BILLING CODE 6450–01–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 23 

[Docket No. FAA–2015–5034; Notice No. 23– 

15–01–SC] 

Special Conditions: Kestrel Aircraft 

Company, Model K–350 Turboprop, 

Lithium Batteries 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed special 

conditions. 

SUMMARY: This action proposes special 

conditions for the Kestrel Aircraft 

Company, Model K–350 Turboprop 

airplane. This airplane will have a novel 

or unusual design feature associated 

with the installation of a rechargeable 

lithium battery. The applicable 

airworthiness regulations do not contain 

adequate or appropriate safety standards 

for this design feature. These proposed 

special conditions contain the 

additional safety standards that the 

Administrator considers necessary to 

establish a level of safety equivalent to 

that established by the existing 

airworthiness standards. 

DATES: Send your comments on or 

before December 21, 2015. 

ADDRESSES: Send comments identified 

by docket number FAA–2015–5034 

using any of the following methods: 

b Federal eRegulations Portal: Go to 

http://www.regulations.gov and follow 

the online instructions for sending your 

comments electronically. 

b Mail: Send comments to Docket 

Operations, M–30, U.S. Department of 

Transportation (DOT), 1200 New Jersey 

Avenue SE., Room W12–140, West 

Building Ground Floor, Washington, DC 

20590–0001. 

b Hand Delivery or Courier: Take 

comments to Docket Operations in 

Room W12–140 of the West Building 

Ground Floor at 1200 New Jersey 

Avenue SE., Washington, DC, between 9 

a.m., and 5 p.m., Monday through 

Friday, except Federal holidays. 

b Fax: Fax comments to Docket 

Operations at 202–493–2251. 

Privacy: The FAA will post all 

comments it receives, without change, 

to http://regulations.gov, including any 

personal information the commenter 

provides. Using the search function of 

the docket Web site, anyone can find 

and read the electronic form of all 

comments received into any FAA 

docket, including the name of the 

individual sending the comment (or 

signing the comment for an association, 

business, labor union, etc.). DOT’s 

complete Privacy Act Statement can be 

found in the Federal Register published 

on April 11, 2000 (65 FR 19477–19478), 

as well as at http://DocketsInfo.dot.gov. 

Docket: Background documents or 

comments received may be read at 

http://www.regulations.gov at any time. 

Follow the online instructions for 

accessing the docket or go to the Docket 

Operations in Room W12–140 of the 

West Building Ground Floor at 1200 

New Jersey Avenue SE., Washington, 

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

through Friday, except Federal holidays. 

FOR FURTHER INFORMATION CONTACT: 

Ruth Hirt, Federal Aviation 

Administration, Small Airplane 

Directorate, Aircraft Certification 

Service, 901 Locust; Kansas City, 

Missouri 64106; telephone (816) 329– 

4108; facsimile (816) 329–4090. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite interested people to take 

part in this rulemaking by sending 

written comments, data, or views. The 

most helpful comments reference a 

specific portion of the special 

conditions, explain the reason for any 

recommended change, and include 

supporting data. We ask that you send 

us two copies of written comments. 

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 these special conditions 

based on the comments we receive. 


rmajette on DSK7SPTVN1PROD with PROPOSALS
68282 Federal Register / Vol. 80, No. 213 / Wednesday, November 4, 2015 / Proposed Rules 

Background 

On November 22, 2011, Kestrel 

Aircraft Company applied for a type 

certificate for their new Model K–350. 

The Kestrel Aircraft Company Model K– 

350 is a single-engine turboprop 

airplane with the primary structure 

constructed largely of carbon and epoxy 

composite material. The turboprop 

engine will be a Honeywell Model 

TPE331–14GR–801KT that is integrated 

with a Hartzell 4 bladed, 110-inch 

carbon composite propeller. The 

standard seating configuration offers a 

one plus five cabin (one pilot and five 

passengers). Alternate interior 

configurations will be available from 

two seats (cargo configuration) up to 

eight seats total. The K–350 will 

incorporate an integrated avionics 

system, retractable landing gear, and a 

conventional tail configuration. 

Specifications expected for the K–350 

include the following: 

• Maximum altitude: 31,000 Feet 

• Maximum cruise speed: 320 Knots 

True Air Speed 

• Maximum takeoff weight: 8,900 

Pounds 

• Maximum economy cruise: 1,200 

Nautical Miles 

The K–350 will be certified for singlepilot operations under part 91 and part 

135 operating rules. The following 

operating conditions will be included: 

• Day and Night Visual Flight Rules 

• Instrument Flight Rules 

• Flight Into Known Icing (Phase B 

certification) 

Kestrel Aircraft Company proposes to 

utilize a rechargeable lithium Main 

Battery on their new Model K–350 

turboprop airplane. The current 

regulatory requirements for part 23 

airplanes do not contain adequate 

requirements for the application of 

rechargeable lithium batteries in 

airborne applications. This type of 

battery possesses certain failure and 

operational characteristics with 

maintenance requirements that differ 

significantly from that of the nickel 

cadmium and lead acid rechargeable 

batteries currently approved in other 

normal, utility, acrobatic, and commuter 

category airplanes. Therefore, the FAA 

is proposing this special condition to 

require that (1) all characteristics of the 

rechargeable lithium batteries and their 

installation that could affect safe 

operation of the K–350 are addressed, 

and (2) appropriate Instructions for 

Continued Airworthiness that include 

maintenance requirements are 

established to ensure the availability of 

electrical power from the batteries when 

needed. 

Type Certification Basis 

Under the provisions of 14 CFR 21.17, 

Kestrel Aircraft Company must show 

that the K–350 meets the applicable 

provisions of part 23, as amended by 

amendments 23–1 through 23–62 

thereto. 

If the Administrator finds that the 

applicable airworthiness regulations 

(i.e., 14 CFR part 23) do not contain 

adequate or appropriate safety standards 

for the K–350 because of a novel or 

unusual design feature, special 

conditions are prescribed under the 

provisions of § 21.16. 

Special conditions are initially 

applicable to the model for which they 

are issued. Should the type certificate 

for that model be amended later to 

include any other model that 

incorporates the same or similar novel 

or unusual design feature, the special 

conditions would also apply to the other 

model under § 21.101. 

In addition to the applicable 

airworthiness regulations and special 

conditions, the K–350 must comply 

with the fuel vent and exhaust emission 

requirements of 14 CFR part 34 and the 

noise certification requirements of 14 

CFR part 36, and the FAA must issue a 

finding of regulatory adequacy under 

§ 611 of Public Law 92–574, the Noise 

Control Act of 1972. 

The FAA issues special conditions, as 

defined in 14 CFR 11.19, in accordance 

with § 11.38, and they become part of 

the type-certification basis under 

§ 21.17(a)(2). 

Novel or Unusual Design Features 

The K–350 will incorporate the 

following novel or unusual design 

feature: Installation of a rechargeable 

lithium battery as the Main or Engine 

Start aircraft battery. 

Discussion 

The current regulatory requirements 

for part 23 airplanes do not contain 

adequate requirements for the 

application of rechargeable lithium 

batteries in electrical system design. 

This type of battery possesses certain 

failures with operational characteristics 

and maintenance requirements that 

differ significantly from that of the 

nickel cadmium and lead acid 

rechargeable batteries currently 

approved in other normal, utility, 

acrobatic, and commuter category 

airplanes. Therefore, the FAA is 

proposing this special condition to 

require that (1) all characteristics of the 

rechargeable lithium batteries and their 

installation that could affect safe 

operation of the K–350 are addressed, 

and (2) appropriate Instructions for 

Continuous Airworthiness which 

include maintenance requirements are 

established to ensure the availability of 

electrical power from the batteries when 

needed. 

As previously mentioned, Kestrel 

Aircraft Company proposes to utilize a 

rechargeable lithium Main Battery on 

their new Model K–350 turboprop 

airplane. At the Kestrel Preliminary 

Type Certification Board Meeting it was 

brought to the attention of the FAA that 

the Lithium battery used in the K–350 

will be qualified to RTCA standards 

DO–311, titled Minimum Operational 

Performance Standards for Rechargeable 

Lithium Battery Systems. Additionally, 

on July 18, 2013, Kestrel advised the 

Civil Aviation Contingency Operations 

(CACO) that the battery will have 

Technical Standard Order Authorization 

for TSO C–179a, titled Permanently 

Installed Rechargeable Lithium Cells, 

Batteries and Battery Systems. Finally, 

Kestrel plans to use the same 

manufacturer for both the lithium 

battery and the battery controller. 

Presently, there is limited experience 

with use of rechargeable lithium 

batteries in applications involving 

commercial aviation. However, other 

users of this technology, ranging from 

wireless telephone manufacturers to the 

electric vehicle industry, have noted 

safety problems with lithium batteries. 

These problems include overcharging, 

over-discharging, and flammability of 

cell components, described in the 

following: 

1. Overcharging: In general, lithium 

batteries are significantly more 

susceptible to internal failures that can 

result in self-sustaining increases in 

temperature and pressure (i.e., thermal 

runaway) than the nickel-cadmium or 

lead-acid counterparts. This is 

especially true for overcharging which 

causes heating and destabilization of the 

components of the cell, leading to the 

formation (by plating) of highly unstable 

metallic lithium. The metallic lithium 

may ignite, resulting in a fire or 

explosion. Finally, the severity of 

thermal runaway due to overcharging 

increases with increasing battery 

capacity and physical size. 

2. Over-discharging: Discharge of 

some types of lithium battery cells 

beyond a certain voltage (typically 2.4 

volts) can cause corrosion of the 

electrodes of the cell, resulting in loss 

of battery capacity that cannot be 

reversed by recharging. This loss of 

capacity may not be detected by the 

simple voltage measurements 

commonly available to flight crews as a 

means of checking battery status, which 

is a problem shared with nickelcadmium batteries. 


rmajette on DSK7SPTVN1PROD with PROPOSALS
Federal Register / Vol. 80, No. 213 / Wednesday, November 4, 2015 / Proposed Rules 68283 

3. Flammability of Cell Components: 

Unlike nickel-cadmium and lead-acid 

batteries, some types of lithium batteries 

use liquid electrolytes that are 

flammable. The electrolyte may serve as 

a source of fuel for an external fire, if 

there is a breach of the battery 

container. 

These problems experienced by users 

of lithium batteries raise concern about 

the use of these batteries in commercial 

aviation. The intent of the proposed 

special condition is to establish 

appropriate airworthiness standards for 

lithium battery installations in the K– 

350 and to ensure, as required by 

§§ 23.1309 and 23.601, that these battery 

installations are not hazardous or 

unreliable. 

Applicability 

As previously discussed, these special 

conditions are applicable to the K–350. 

Should Kestrel Aircraft Company apply 

at a later date for a change to the type 

certificate to include another model 

incorporating the same novel or unusual 

design feature, the special conditions 

would apply to that model as well. 

Conclusion 

This action affects only certain novel 

or unusual design features on one model 

of airplane. It is not a rule of general 

applicability. 

List of Subjects in 14 CFR Part 23 

Aircraft, Aviation safety, Signs and 

symbols. 

■ The authority citation for these 

special conditions is as follows: 

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

44702, 44704. 

The Proposed Special Conditions 

■ Accordingly, the Federal Aviation 

Administration (FAA) proposes the 

following special conditions as part of 

the type certification basis for Kestrel 

Aircraft Company, Model K–350 

Turboprop airplanes. 

1. Kestrel Aircraft Company, Model 

K–350 Turboprop, Lithium Batteries. 

The FAA proposes special conditions 

that adopt the following requirements: 

(a) The flammable fluid fire protection 

requirement is § 23.863. In the past, this 

rule was not applied to batteries of 

normal, utility, acrobatic, and commuter 

category airplanes since the electrolytes 

utilized in lead-acid batteries and 

nickel-cadmium batteries are not 

flammable. 

(b) New Instructions for Continuous 

Airworthiness that include maintenance 

requirements to ensure that batteries 

used as spares have been maintained in 

an appropriate state of charge and 

installed lithium batteries have been 

sufficiently charged at appropriate 

intervals. These instructions must also 

describe proper repairs, if allowed, and 

battery part number configuration 

control. 

(c) The applicant must conduct a 

system safety assessment for the failure 

condition classification of a failure of 

the battery charging and monitoring 

functionality (per Advisory Circular 

23.1309–1E), and develop mitigation to 

preclude any adverse safety effects. 

Mitigation may include software, 

Airborne Electronic Hardware (AEH) or 

a combination of software and 

hardware, which should be developed 

to the appropriate Design Assurance 

Level(s) (DALs), respectively (per 

Advisory Circular 20–115C and 

Advisory Circular 20–152). 

(d) New requirements, listed in 

paragraph (e), address the hazards of 

overcharging and over-discharging that 

are unique to lithium batteries, which 

should be applied to all rechargeable 

lithium battery and battery installations 

on the Model K–350 airplane in lieu of 

the requirements of 

§ 23.1353(a)(b)(c)(d)(e), amendment 23– 

62. 

Note 1: These special conditions are 

not intended to replace 

§ 23.1353(a)(b)(c)(d)(e) at amendment 

23–62 in the certification basis of 

airplane K–350 series airplanes. These 

special conditions apply only to 

rechargeable lithium batteries and 

lithium battery systems and their 

installations. The requirements of 

§ 25.1353 at amendment 23–62 remains 

in effect for batteries and battery 

installations on K–350 series that do not 

use newly technologically developed 

batteries. 

(e) Rechargeable lithium batteries and 

battery installations on the Model K– 

350 airplane must be designed and 

installed as follows: 

(1) Safe cell temperatures and 

pressures must be maintained during— 

i. Normal operations; 

ii. Any probable failure conditions of 

charging or discharging or battery 

monitoring system; 

iii. Any failure of the charging or 

battery monitoring system not shown to 

be extremely remote. 

(2) The rechargeable lithium battery 

installation must be designed to 

preclude explosion or fire in the event 

of (e)(1)(ii) and (e)(1)(iii) failures. 

(3) Design of the rechargeable lithium 

batteries must preclude the occurrence 

of self-sustaining, uncontrolled 

increases in temperature or pressure. 

(4) No explosive or toxic gasses 

emitted by any rechargeable lithium 

battery in normal operation or as the 

result of any failure of the battery 

charging system, monitoring system, or 

battery installation which is not shown 

to be extremely remote, may accumulate 

in hazardous quantities within the 

airplane. 

(5) Installations of rechargeable 

lithium batteries must meet the 

requirements of § 23.863(a) through (d) 

at amendment 23–34. 

(6) No corrosive fluids or gases that 

may escape from any rechargeable 

lithium battery may damage 

surrounding structure or any adjacent 

systems, equipment, electrical wiring, or 

the airplane in such a way as to cause 

a major or more severe failure condition, 

in accordance with § 23.1309(c) at 

amendment 23–62 and applicable 

regulatory guidance. 

(7) Each rechargeable lithium battery 

installation must have provisions to 

prevent any hazardous effect on 

structure or essential systems that may 

be caused by the maximum amount of 

heat the battery can generate during a 

short circuit of the battery or of its 

individual cells. 

(8) Rechargeable lithium battery 

installations must have— 

i. A system to automatically control 

the charging rate of the battery to 

prevent battery overheating and 

overcharging, or; 

ii. A battery temperature sensing and 

over-temperature warning system with a 

means for automatically disconnecting 

the battery from its charging source in 

the event of an over-temperature 

condition, or; 

iii. A battery failure sensing and 

warning system with a means for 

automatically disconnecting the battery 

from its charging source in the event of 

battery failure. 

(9) Any rechargeable lithium battery 

installation functionally required for 

safe operation of the airplane must 

incorporate a monitoring and warning 

feature that will provide an indication 

to the appropriate flight crewmembers 

whenever the State of Charge (SOC) of 

the batteries has fallen below levels 

considered acceptable for dispatch of 

the airplane. 

(10) The Instructions for Continued 

Airworthiness required by § 23.1529 at 

amendment 23–26 must contain 

maintenance requirements to assure that 

the battery has been sufficiently charged 

at appropriate intervals specified by the 

battery manufacturer and the equipment 

manufacturer that contain the 

rechargeable lithium battery or 

rechargeable lithium battery system. 

This is required to ensure that lithium 

rechargeable batteries and lithium 

rechargeable battery systems will not 

degrade below specified ampere-hour 


rmajette on DSK7SPTVN1PROD with PROPOSALS
68284 Federal Register / Vol. 80, No. 213 / Wednesday, November 4, 2015 / Proposed Rules 

levels sufficient to power the aircraft 

system. The Instructions for Continued 

Airworthiness must also contain 

procedures for the maintenance of 

replacement batteries in spares storage 

to prevent the installation of batteries 

that have degraded charge retention 

ability or other damage due to 

prolonged storage at a low state of 

charge. Replacement batteries must be 

of the same manufacturer and part 

number as approved by the FAA. 

Note 2: The term ‘‘sufficiently 

charged’’ means that the battery will 

retain enough of a charge, expressed in 

ampere-hours, to ensure that the battery 

cells will not be damaged. A battery cell 

may be damaged by lowering the charge 

below a point where there is a reduction 

in the ability to charge and retain a full 

charge. This reduction would be greater 

than the reduction that may result from 

normal operational degradation. 

(11) In showing compliance with the 

proposed special conditions herein, 

paragraphs (e)(1) through (e)(8), and the 

RTCA document, Minimum Operational 

Performance Standards for Rechargeable 

Lithium Battery Systems, DO–311, may 

be used. The list of planned DO–311 

tests should be documented in the 

certification or compliance plan and 

agreed to by the CACO. Alternate 

methods of compliance other than DO– 

311 tests must be coordinated with the 

directorate and CACO. 

Issued in Kansas City, Missouri, on 

October 28, 2015. 

Robert Busto, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2015–28125 Filed 11–3–15; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2015–3778; Directorate 

Identifier 2015–NE–27–AD] 

RIN 2120–AA64 

Airworthiness Directives; Rolls-Royce 

plc Turbofan Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We propose to adopt a new 

airworthiness directive (AD) for all 

Rolls-Royce plc (RR) RB211–535E4–37, 

RB211–535E4–B–37, and RB211– 

535E4–C–37 turbofan engines. This 

proposed AD was prompted by a review 

of operational data that determined 

certain RR RB211–535E4–37 engines 

have been operated to a more severe 

flight profile than is consistent with the 

flight profile used to establish the cyclic 

life limits for the rotating parts. This 

proposed AD would require 

recalculating the cyclic life for certain 

engine life-limited rotating parts and 

removing those parts that have exceeded 

their cyclic life limit within specified 

compliance times. We are proposing 

this AD to prevent failure of life-limited 

rotating parts, which could result in 

uncontained parts release, damage to 

the engine, and damage to the airplane. 

DATES: We must receive comments on 

this proposed AD by December 4, 2015. 

ADDRESSES: You may send comments by 

any of the following methods: 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov. Follow the 

instructions for submitting comments. 

• Mail: Docket Management Facility, 

U.S. Department of Transportation, 1200 

New Jersey Avenue SE., West Building 

Ground Floor, Room W12–140, 

Washington, DC 20590–0001. 

• Hand Delivery: Deliver to Mail 

address above between 9 a.m. and 5 

p.m., Monday through Friday, except 

Federal holidays. 

• Fax: 202–493–2251. 

For service information identified in 

this proposed AD, contact Rolls-Royce 

plc, Corporate Communications, P.O. 

Box 31, Derby, England, DE24 8BJ; 

phone: 011–44–1332–242424; fax: 011– 

44–1332–249936; email: http://

www.rolls-royce.com/contact/civil_

team.jsp; Internet: https://

customers.rolls-royce.com/public/

rollsroycecare. You may view this 

service information at the FAA, Engine 

& Propeller Directorate, 12 New England 

Executive Park, Burlington, MA. For 

information on the availability of this 

material at the FAA, call 781–238–7125. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http://

www.regulations.gov by searching for 

and locating Docket No. FAA–2015– 

3778; or in person at the Docket 

Operations office between 9 a.m. and 5 

p.m., Monday through Friday, except 

Federal holidays. The AD docket 

contains this proposed AD, the 

mandatory continuing airworthiness 

information (MCAI), the regulatory 

evaluation, any comments received, and 

other information. The address for the 

Docket Office (phone: 800–647–5527) is 

in the ADDRESSES section. Comments 

will be available in the AD docket 

shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Robert Green, Aerospace Engineer, 

Engine Certification Office, FAA, Engine 

& Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

phone: 781–238–7754; fax: 781–238– 

7199; email: robert.green@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments about 

this proposed AD. Send your comments 

to an address listed under the 

ADDRESSES section. Include ‘‘Docket No. 

FAA–2015–3778; Directorate Identifier 

2015–NE–27–AD’’ at the beginning of 

your comments. We specifically invite 

comments on the overall regulatory, 

economic, environmental, and energy 

aspects of this proposed AD. We will 

consider all comments received by the 

closing date and may amend this 

proposed AD based on those comments. 

We will post all comments we 

receive, without change, to http://

www.regulations.gov, including any 

personal information you provide. We 

will also post a report summarizing each 

substantive verbal contact with FAA 

personnel concerning this proposed AD. 

Discussion 

The European Aviation Safety Agency 

(EASA), which is the Technical Agent 

for the Member States of the European 

Community, has issued EASA AD 2015– 

0148, dated July 23, 2015 (corrected July 

24, 2015), referred to hereinafter as ‘‘the 

MCAI’’, to correct an unsafe condition 

for the specified products. The MCAI 

states: 

A review of operational flight data has 

revealed that some RB211–535 engines may 

have been operated beyond the flight profile 

(FP) assumed by the operator when 

establishing the operational limits (life 

limits) within which the corresponding 

critical parts are allowed to remain installed. 

This condition, if not corrected, may lead 

to critical part failure, possibly resulting in 

release of high energy debris, damage to the 

aeroplane and/or injury to the occupants. 

To preclude failure of an engine lifelimited part, the MCAI specifies, and 

this proposed AD would require, 

recalculating the cyclic life for certain 

parts, and removing from service those 

parts that have exceeded their cyclic life 

limit within specified compliance times. 

This proposed AD would establish a 

new default Flight Profile G for RB211– 

535E4–37 engine life-limited parts. If, 

however, operators meet the 

requirements of Appendix 6 of RR Alert 

Non-Modification Service Bulletin 

(NMSB) No. RB.211–72–AH972, 

Revision 3, dated August 28, 2015, they 

may operate to Flight Profile A or B. 

You may obtain further information by 

examining the MCAI in the AD docket 


rmajette on DSK7SPTVN1PROD with PROPOSALS