AFS-11-361-E 

September 29, 2011 

 Exemption No. 10369 

 Regulatory Docket No. FAA-2011-0660 

Mr. Malcom Williams 

Chief Pilot 

Vector Disease Control International, LLC 

1320 Brookwood Drive 

Little Rock, AR 72202 

Dear Mr. Williams: 

This letter is to inform you that we have granted your request for exemption. It transmits our 

decision, explains its basis, and gives you the conditions and limitations of the exemption, 

including the date it ends. 

The Basis for Our Decision 

By letter dated June 20, 2011, you petitioned the Federal Aviation Administration (FAA) on 

behalf of Vector Disease Control International, LLC (Vector Disease Control) for an 

exemption from § 137.53(c)(2) of Title 14, Code of Federal Regulations (14 CFR). 

Section 137.53(c)(2) requires that an aircraft (other than a helicopter) that is being operated 

over a congested area be equipped “with a device capable of jettisoning at least one-half of 

the aircraft’s maximum authorized load of agricultural material within 45 seconds.” The 

exemption that you requested would, if granted, allow Vector Disease Control to conduct 

aerial applications of insecticide materials for the purpose of mosquito control without the 

aircraft being equipped with the device specified in § 137.53(c)(2) when operating over a 

congested area. The exemption would apply to the following aircraft: 
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Registration Number Make/Model 

N415CC Piper PA-23-250 

N40200 Piper PA-23-250 

N737WP Piper PA-23-250 

N251RC Cessna 402C 

The FAA has determined that good cause exists for not publishing a summary of the petition 

in the Federal Register because the requested exemption would not set a precedent, and any 

delay in acting on this petition would be detrimental to Vector Disease Control. 

The FAA’s analysis/summary is as follows: 

Part 137 sets out rules governing the safety of agricultural aircraft operations and the 

dispensing of materials that is conducted during these operations. This part was adopted to 

prescribe adequate and uniform regulations not only for the safety of flight but for the 

protection of the persons and property on the ground. The intent of § 137.53(c)(2) is to 

provide the pilot with a means of dumping chemicals from the aircraft if an emergency 

situation occurs. 

The FAA has previously granted a similar exemption from the requirements of 

§ 137.53(c)(2). In Exemption No. 4820 (copy enclosed), the FAA found that the petitioner’s 

operation would provide a level of safety equivalent to the level required by the regulations 

because: (1) the aircraft used in the operation would have a significant level of reliability; (2) 

the aircraft would be operated with a gross weight considerably less than the maximum 

allowed; and (3) the pilots used in the operation would have experience in excess of the 

regulatory requirements. The FAA also found that a grant of the exemption would be in the 

public interest because it would provide more effective control of widespread insect 

infestations in and around congested areas. 

In this case, Vector Disease Control’s exemption request is similar to the circumstances that 

the FAA addressed in Exemption No. 4820. First, the aircraft used in this operation have 

two-engine reliability and single-engine performance capability, which permit the aircraft to 

fly to a safe area in the event of engine failure. Second, under the conditions imposed by this 

exemption, aircraft would be limited to a maximum gross weight that will ensure singleengine climb performance capability of at least 200-feet-per-minute positive rate at the 

prevailing density altitude. Third, the conditions imposed by this exemption would require 

that the pilots used in the operation have experience that is in excess of the regulatory 

requirements. 

In consideration of the foregoing, I find that a grant of this exemption would provide a level 

of safety equivalent to the level required by the regulations. I also find that a grant of this 

exemption would be in the public interest because it would provide more effective insect 

control in and around congested areas. 
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Our Decision 

Under the authority contained in 49 U.S.C. 40113 and 44701, which the FAA Administrator 

has delegated to me, I hereby grant Vector Disease Control an exemption from 

14 CFR § 137.53(c)(2) to the extent necessary to conduct aerial applications of insecticide 

materials without the aircraft being equipped with a device that is capable of jettisoning at 

least one-half of the aircraft’s maximum authorized load of agricultural materials within 

45 seconds when operating over a congested area, subject to the conditions and limitations 

described below. 

Conditions and Limitations 

1. This exemption is limited to Piper PA-23-250 and Cessna 402C model aircraft 

operated by Vector Disease Control International, LLC (operator). 

2. This exemption is valid only when conducting agricultural aircraft operations under 

14 CFR part 137. 

3. Aircraft operated under this exemption are limited to a maximum gross weight that 

will ensure single-engine climb performance capability of at least 200-feet-per-minute 

positive rate at the prevailing density altitude. 

4. Prior to each flight, the operator or pilot in command (PIC) must prepare a document 

showing the weight and balance calculations and the single-engine climb performance 

for the forecast operating density altitude. The document must be retained by the 

operator for at least 30 days and presented to the Administrator upon request. 

5. Each PIC of an aircraft operated under this exemption must have a total of at least 

1,200 hours of flight time as pilot, including at least 200 hours PIC time in pistonpowered multiengine aircraft, 50 hours of which must have been in part 137 

operations. 

6. The operator must provide a copy of this exemption to each PIC who operates under 

the terms of this exemption. 

7. A copy of the exemption must be carried on the aircraft while conducting operations 

under the terms of this exemption. 

8. Prior to operating under this exemption, each PIC must have successfully completed 

flight instruction from an appropriately rated flight instructor on single-engine 

operations, performance, and handling characteristics of the Piper PA-23-250 or 

Cessna 402C model aircraft (as applicable). The instruction must be provided in each 

model of aircraft the PIC will operate under this exemption. A record of this 

instruction must be made available by the PIC upon request of the Administrator. 
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9. The operator must provide a copy of this exemption to its part 137 certificate-holding 

Flight Standards District Office. 

10. This exemption is not valid for operations outside of the United States. 

This exemption terminates on September 30, 2013, unless sooner superseded or rescinded. 

Sincerely, 

/s/ 

John W. McGraw 

Acting Director, Flight Standards 

 

Enclosure