U.S. Department

oflianspoftation

FdddndAvicltkn

Admhmmion

Subject: Date= l/29/91 AC No: 20422A -'

ANTI-MISFUELING DEVICES:

THEIR AVAILABILITY AND USE

Initiated by: ~~$340 ChdUlgt:

1. ---1--m PURPOSE. This adhsory circular (AC) explains the benefits of fitting

reciprocating engine-powered general aviation aircraft with anti-misfueling

devices and the fitting of fuel dispensing equipment with special fuel hose

nozzle spouts.

2 CANCELLATION. AC 20-122, Anti-misfueling Devices: Their Availability and

U;e,-dat;d-o%Ler 5, 1984, is cancelled.

3. RELATED FEDERAL AVIATION REGULATIONS iFAR SECTIONS. --CIC--------LI----III)--------LI-~L----II- c-w ------e--

FAR Sections 23.1557, 27.1557, 43.3, 43.5, 43.9, 91.3(a), 91.5, and 139.321.

4. ---III--I-C--------------. RELATED READING MATERIAL. AC OO-34A, Aircraft Ground Handling and

Servicing; AC 20043C, Aircraft Fuel Control; AC 20-116, Marking Aircraft Fuel

Filler Openings With Color Coded Decals; and AC 150/5230-4, Aircraft Fuel

Storage, Handling, and Dispensing on Airports.

5 . BACKGROUND. ------II--

a. Aviation statistics indicate that the use of improper fuel has caused

or contributed to an inordinate number of accidents and incidents. Most of

these have involved single-engine general aviation aircraft (and some

multiengine) that were misfueled with jet or turbine engine fuel instead of

gasoline which these aircraft use. Misfueling a reciprocating engine-powered

aircraft with jet or turbine engine fuel can and has produced catastrophic

results when engines failed during the critical takeoff phase of flight. .

b. A specification developed by the General Aviation Manufacturers

Association (GAMA), Specification No. 3 issued on July 1, 1982, provides a

standard color coded decal to be affixed adjacent to aircraft fuel tank filler

openings and corresponding color decal bands tb be affixed to refuelers' fuel

hoses. Both decals were designed to alert servicing personnel as to the

proper fuel to be used.

c. The National Air Transportation Association (NATA) and GAMA are

cooperating in an additional effort which will significantly mitigate the

chances of misfueling. Fuel tank filler openings in reciprocating

engine-powered aircraft may be equipped with pilot-installed adapter rings

reducing the opening size from 3" to 2.3" in diameter. Jet or turbine engine

fuel nozzle assemblies will be equipped with spouts with a minimum diameter of

2.6", thereby reducing the probability of introducing jet or turbine engine

fuel nozzles into the filler openings of aircraft requiring gasoline.
AC 204228 l/29/91

6. DISCUSSION.

--e-p -

a. The down-size adapter rings are being made available through the

aircraft manufacturer-2 original equipment manufacturer (OEM). Individual

OEM's have developed, or are developing, service'information for each

conversion kit to ensure proper type and installation. Owners and operators

of reciprocating engine-powered aircraft should seriously consider equipping

each fuel tank fille,r opening with these adapters since safety will be

significantly enhanced, and in some cases, the cost is being defrayed by

insurance companies. Check with your aircraft manufacturer or insurance

company to determine its participation. Since January 1, 1985, all GAMA

member companies' newly-produced airplanes have fueling ports that meet the

dimensions defined in the Society of Automotive Engineers' (SAE) Aerospace

Standard (AS) 1852.

b l Fuel tank filler opening adapters may be installed by pilots only when

accomplished in accordance with OEM service information. Consistent with FAR

Section 43.3(g), the fuel tank filler opening adapters may be installed by at

least a certificated pilot. The installations must be approved for returr! to

service under Section 43.7 and recorded as required by Section 43;9(a).

- - Note-: The installation of these adapters may be performed on

an aircraft owned or operated by the holder of a pilot

certificate issued under Part 61, as long as the aircraft is

not used under Parts121, 127, 129, or 135.

c. In the interest of safety and standardization, it is recommended that

Fixed Base Operators (FBO) and other aviation fuel suppliers equip their

turbine fueling equipment (trucks, islands, pumps, etc.) with the larger size

nozzles designated in SAE AS 1852 to prevent misfueling reciprocating engined

aircraft with turbine fuel. SAE AS 1852 defines maximum free opening

dimensions for airframe refueling ports on civil aircraft that require the

exclusive use of aviation gasolines, and minimum free opening dimensions for

airframe refueling ports on civil aircraft that operate with turbine fuels as

a primary type fuel. In addition, the aerospace standard defines the minimum

refueling nozzle tip dimensions for turbine fuel ground service equipment and

the maximum refueling nozzle tip diameter dimension for aviation gasoline

ground service equipment.

d Airport owners should amend their airport operations manual to

encouiage FBO's and other suppliers to meet the new size specifications for

jet fuel nozzle spouts, and to do so within a specified time period.

2 Par 6

l/29/91 AC 20422A

e. For more information, interested parties should contact the

manufacturer of their aircraft or General Aviation Manufacturers kssociation,

1400 K Street NW., Suite 801, Washington, D.C. 20005, telephone (202)

393-1500; National Air Transportation Association, 4226 King Street,

Alexandria, Virginia 22303, telephone (703) 845-9000; or the Society of

Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, Pennsylvania

15096, telephone (412) 776-4841.

,vL-pQJ _ Thomas C. Accarai

Acting Director, Flight Standards Service

Par 6

USDepartment

of Transportation

IFederal Aviution

AdministrMon

800 Independence Ave.,

Washington, DC. 20591

3

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