AFS-14-405-E

Exemption No. 13183

UNITED STATES OF AMERICA

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

WASHINGTON, DC 20591

In the matter of the petition of

GREAT LAKES AVIATION, LTD. Regulatory Docket No. FAA-2014-0558

for an exemption from § 135.223

of Title 14, Code of

Federal Regulations

DENIAL OF EXEMPTION

 By letter posted to the docket on August 4, 2014, Mr. Joseph Linnebur, Director of 

Operations, Great Lakes Aviation, Ltd., 1022 Airport Parkway, Cheyenne, Wyoming 82001

petitioned the Federal Aviation Administration (FAA) on behalf of Great Lakes Aviation, Ltd.

(Great Lakes) for an exemption from §135.223 of Title 14, Code of Federal Regulations 

(14 CFR). The proposed exemption, if granted, would allow Great Lakes to use the alternate 

weather requirements of § 121.619 in lieu of the requirements of §135.223 for all domestic 

operations conducted under part 135.

The petitioner requests relief from the following regulation:

Section 135.223, “Instrument Flight Rules (IFR): Alternate airport requirements,”

prescribes, in pertinent part that:

(a) Except as provided in paragraph (b) of this section, no person may operate an aircraft 

in IFR conditions unless it carries enough fuel (considering weather reports or forecasts 

or any combination of them) to—

(1) Complete the flight to the first airport of intended landing;

(2) Fly from that airport to the alternate airport; and
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(3) Fly after that for 45 minutes at normal cruising speed or, for helicopters, fly after that 

for 30 minutes at normal cruising speed.

(b) Paragraph (a)(2) of this section does not apply if part 97 of this chapter prescribes a 

standard instrument approach procedure for the first airport of intended landing and, for 

at least one hour before and after the estimated time of arrival, the appropriate weather 

reports or forecasts, or any combination of them, indicate that—

(1) The ceiling will be at least 1,500 feet above the lowest circling approach minimum 

descent altitude (MDA); or

(2) If a circling instrument approach is not authorized for the airport, the ceiling will be 

at least 1,500 feet above the lowest published minimum or 2,000 feet above the airport 

elevation, whichever is higher; and

(3) Visibility for that airport is forecast to be at least three miles, or two miles more than 

the lowest applicable visibility minimums, whichever is the greater, for the instrument 

approach procedure to be used at the destination airport.

The petitioner supports its request with the following information:

Great Lakes petitions for relief in order to use the alternate weather requirements of § 121.619 

instead of § 135.223 for all of its domestic operations. The petitioner states that it operates the 

Beech 1900 under both its part 121 and 135 operating certificates. Great Lakes proposes to 

use one set of rules (§ 121.619) for determining whether an alternate airport is required for its 

entire operation.

Great Lakes contends that § 135.223 and § 121.619 provide similar requirements for 

determining if an alternate airport is required for a flight. The petitioner expresses its 

understanding that § 121.619 and § 135.223 assume there will be an adequate margin between 

the weather requirements in the rules and the minimums imposed for the instrument approach 

procedure available at the airport. Based on this understanding, the petitioner asserts that 

using the alternate weather requirements of § 121.619 for all of its operations would always 

provide for an adequate weather margin between the alternate weather requirement and 

instrument approach minimums. 

Great Lakes assumes that § 135.223 is more restrictive than § 121.619 because of the limited 

requirements for dispatchers in part 135 operations. Specifically, the petitioner contends that 

the increased weather margin of § 135.223 would increase safety for a pilot-in-command 

(PIC) who does not have the benefit of continuous weather updates from a dispatch center 

should un-forecasted weather prevent arrival at the airport. Great Lakes emphasizes that the 

exemption would be contingent on all flights, including those conducted under part 135, being 

dispatched in accordance with part 121, Subpart U. The petitioner states that its flights are 

under constant surveillance by a dispatcher and capable of continuous communication with 

the company’s dispatch center in Cheyenne, Wyoming.
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The petitioner argues that a grant of exemption would maintain an equivalent level of safety 

because all flights would be dispatched by a Great Lakes dispatcher. Great Lakes contends 

that, with a dispatcher continuously monitoring each flight, any weather changes that could 

reduce adequate weather margins can be communicated to PIC to facilitate changes to the 

flight plan before reaching the airport. The petitioner states that these procedures are already 

included in its standard operating procedures and have been in use since Great Lakes became 

a part 121 operator. In addition, Great Lakes states that all flights are conducted by two 

qualified crew members, which it feels adds to safety when weather becomes a factor. 

Great Lakes asserts that, should this exemption be granted, it “would effectively continue to 

operate at the same levels as any equivalent part 121 carrier.” The petitioner cites 

technological advances in weather forecasting, improved weather monitoring equipment, 

advanced communication capabilities, and improvements in flight crew training requirements 

as factors contributing to its ability to maintain an equivalent level of safety. 

Great Lakes requests the ability to utilize § 121.619 for determining alternate weather 

requirements for its part 135 operations subject to the following proposed conditions and 

limitations:

1. All part 135 flights are to be dispatched and under continuous surveillance by a Great 

Lakes dispatcher, trained in accordance with Great Lakes’ approved dispatcher 

program. 

2. All part 135 flights will be dispatched in accordance with part 121, Subpart U. 

3. Each dispatcher will be provided a system to display the location of each flight and 

current/significant weather. 

4. The dispatch system will have a system to alert the dispatcher when there is a change 

to a weather forecast, METAR, or a special weather update. 

5. Great Lakes will provide a means of communication to allow all flight crews and 

dispatchers continuous communication ability for weather changes, dispatch release 

changes, etc. throughout Great Lakes’ route structure. 

6. This relief will be applicable only to airports within the 48 contiguous United States 

and the District of Columbia. 

Great Lakes contends that a grant of exemption would be in the public interest because it 

would “provide a level of safety in the event of un-forecasted weather should cause ceilings 

and visibilities to drop and still allow enough margin to complete the flight.” In addition, the 

petition asserts that a grant of exemption would be in the public interest because having both 

parts 121 and 135 operations dispatched according to the same alternate weather requirements 

will create consistency and reduce possible errors in determining correct alternate weather 

minimums. 
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A summary of the petition was published in the Federal Register on October 17, 2014, 

(79 FR 62512). No comments were received.

The FAA’s analysis is as follows:

The FAA has considered the petitioner’s request and supporting materials and finds that a 

grant of exemption would not be in the public interest or provide a level of safety equivalent 

to that provided by the current regulations.

The FAA finds that § 135.223 contains more restrictive alternate airport requirements than 

§ 121.619. The petitioner assumes § 135.223 “is more restrictive in nature due to the limited 

requirements for dispatchers for carriers that operate under [part] 135.” The petitioner 

contends that public safety would not be affected while utilizing § 121.619 alternate weather 

requirements for its part 135 operations because all flights would be dispatched and followed 

by a Great Lakes dispatcher in accordance with part 121, Subpart U. 

The FAA agrees that certificated aircraft dispatchers play an important role in confirming the 

work of the pilot and providing the flight crew with updates on weather and alternate airports. 

However, there are key differences between the requirements of part 135 and part 121, beyond 

the requirement to use certificated dispatchers, that must be considered in the FAA’s 

evaluation of whether the requested relief would maintain a level of safety at least equal to 

that provided by the rule. For example, § 121.436 requires both the PIC as well as the second 

in command (SIC) to hold an airline transport pilot (ATP) certificate. In addition, to serve as 

PIC, the pilot must have completed 1,000 hours as a SIC in part 121 operations. In contrast, 

§ 135.245 does not require the SIC to have an ATP certificate. Further, the operating 

experience requirements in § 135.244 are not equivalent to those required by § 121.436. In 

sum, a part 121 domestic operation and a part 135 commuter operation must meet different 

crewmember certificate and operating experience requirements. Therefore, the FAA finds that 

the petitioner has failed to demonstrate how permitting it to conduct part 135 operations under 

the less restrictive alternate airport requirements of § 121.619 without compliance with other, 

more restrictive requirements of part 121 would provide a level of safety at least equal to that 

provided by the rule. 

In 1995, the FAA granted relief from § 135.223 to Trans States Airlines (Exemption 

No. 6174). However, the FAA finds that the circumstances in Exemption No. 6174 are 

distinct from those presented by Great Lakes. The grant to Trans States was temporary in 

nature. In granting exemption to Trans States, the FAA noted that efforts were underway to 

bring part 135 commuters under the provisions of part 121 domestic rules and that the grant of 

exemption would support the petitioner’s transition to a part 121 air carrier. The Commuter 

Operations and General Certification and Operations Requirements final fule, published in 

1995 (60 FR 65832), required all scheduled airline passenger operations with aircraft having 

10 seats or more to be operated under the same safety rules that apply to larger (part 121) 

aircraft. As a result of this rule, some air carriers previously designated as part 135 commuters 

transitioned the entirety of their operations to part 121. Whereas, others adjusted operations 

(e.g. by removing seats, by providing on-demand rather than scheduled service) to continue 
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operating under part 135 and avoid complying with the more restrictive requirements of 

part 121. The FAA notes that Great Lakes operates with a “split” certificate, with some of its 

operations under part 135 and some of its operations under part 121. The FAA notes that, 

unlike the situation with Trans States, Great Lakes is not in the process of transitioning its 

part 135 operations to compliance with the entirety of part 121.

The part 121 regulatory scheme provides a network of safety features. In the Commuter 

Operations and General Certification and Operations Requirements final rule, the FAA stated, 

“It is critically important to impose the bulk of the part 121 regulatory scheme on affected 

commuters [those required to transition to part 121] because the absence of any significant 

portion of that regulatory scheme may lessen the effectiveness of the rest of the safety features 

in the part 121 regulatory scheme.” (60 FR 65836) The FAA finds this principle applicable in

this case. Parts 121 and 135 each include a unique set of requirements that, when taken 

together, establish the minimum requirements that must be met to ensure safe operations 

under each part. The FAA finds that allowing the petitioner to selectively comply with 

portions of various rules would not provide a level of safety at least equal to that provided by 

the rule. Further, the FAA finds that a grant of exemption in these circumstances would set a 

poor precedent that a part 135 operator can selectively comply with less restrictive portions of 

part 121 without adopting the network of safety standards as a whole. 

The FAA’s Decision

 In consideration of the foregoing, I find that a grant of exemption would not provide an 

equivalent level of safety. Therefore, pursuant to the authority contained in 49 U.S.C. 

§§ 106(f), 40113, and 44701, delegated to me by the Administrator, the Great Lakes Aviation, 

Ltd. petition for an exemption from 14 CFR 121.467(b)(13) is denied.

Issued in Washington, DC, on October 8, 2015 .

/s/

John S. Duncan

Director, Flight Standards Service