Elasto Proxy has partnered with a manufacturer of aerospace silicones and is ready to fabricate aircraft parts from AA 59588, AMS, and MIL-DTL-25988 materials. Each batch we source comes with a certificate of analysis (COA) that contains laboratory test results and demonstrates compliance with a specific standard. The following sections describe the aerospace silicones and fluorosilicones you can buy from Elasto Proxy in Canada or the United States, and that we can fabricate into finished parts for you.

AA 59588 Silicones | silicone seals
AA 59588 Silicones

AA 59588 Silicones

AA 59588 is a U.S. General Service Administration (GSA) specification that divides aerospace silicones into six classes, each with durometer-based grades on the Shore A scale. A-A-59588, as this GSA specification is sometimes written, supercedes ZZ-R-765/GEN, an older standard referenced by National Stock Number (NSN) 5330-01-371-7183 to ensure standardization among military buyers in NATO countries. AA 59588 also contains commercial item descriptions (CID) with performance characteristics.

AA 59588 aerospace silicones are valued for their resistance to high temperatures, low temperatures, tear, and flex fatigue. Flex, or flexural fatigue, is cracking caused by cyclical stresses and strains. Small cracks propagate into larger cracks that, ultimately, can result in failure. Fully-compliant AA 59588 silicones must pass the DeMattia Flex Resistance test, which measures crack growth in inches over thousands of flexural cycles.

The table below provides an overview of the AA 59588 silicones that Elasto Proxy can fabricate into aircraft parts such as engine mounts, vibration-isolating mounts, and exhaust hangers. Other suppliers claim that their materials are A-A-59588 compliant, but our compounding partner can provide us with silicones that meet more than just non-flexural (e.g., tensile strength) requirements.  That’s important because any time an aircraft is flown, factors such as atmospheric pressure and turbulence cause fatigue.

Class

Description

Grades

1A

Low temperature resistant

40, 50, 60, 70, 80

1B

Low temperature resistant

Low compression set at high temperature

40, 50, 60, 70, 80

2A

High temperature resistant

40, 50, 60, 70, 80

2B

High temperature resistance

Low compression set

30, 50, 60

3A

Low temperature resistance

Tear resistant

Flex resistant

30,50,60

3B

Tear resistant

Flex resistant

30, 50, 60, 70, 80

AMS Silicones
AMS Silicones

AMS Silicones

AMS silicones meet Aerospace Materials Specification (AMS) standards from SAE International, which was known formerly as the Society of Automotive Engineers (SAE). AMS specifications have four-digit numbers (e.g., AMS 3345) and are part of large and comprehensive database of aerospace materials. When AMS standards are revised, a sequential letter is appended to the numbered designation (e.g., AMS 3345G). Sometimes, AMS specifications are written as a long alphanumeric string (e.g., AMS3345G) without any spaces.   

Silicones aren’t the only materials that have AMS numbers, but AMS silicones are used widely in aviation because they resist weathering and petroleum-based lube oils. They also remain flexible over a wide temperature range and resist heat aging. In addition, AMS silicones can be pigmented so that their colors match larger product designs. Typically, these materials are supplied as sheets, strips, tubing, extrusions, and molded shapes.

The table below describes the AMS silicones that Elasto Proxy can fabricate into aircraft parts.

AMS Number

Durometer

Description

AMS 3301

40

General-purpose

AMS 3302

50

Heat and weather resistant

AMS 3303

60

General-purpose

AMS 3304

70

Heat and weather resistant

AMS 3305

80

General-purpose

AMS 3325

60

Fuel and oil resistant

AMS 3345

50

1000 psi

AMS 3356E

60

Lubricating oil and compress set resistant

Electrical grade

MIL-DTL-25988 Fluorosilicones

MIL-DTL-25988 is a U.S. military detail (DTL) specification that covers fluorosilicones for aerospace applications. With their fluorine additions, these silicone elastomers resist petroleum-based fuels and oils, solvents, and harsh chemicals. MIL-DTL-25988 fluorosilicones also withstand a wide range of temperatures and maintain their tear and tensile strength when immersed in jet fuel. These fuel-resistant materials can withstand repeated flexing without stress cracking and remain flexible and rubbery.

The MIL-DTL-25988 specification divides compliant fluorosilicones into different types, classes, and grades. Type 1 materials are for O-rings and Type 2 materials are for sheets, strips, and extruded shapes. Type 2 fluorosilicones are also used in molded parts except for compression seals. Class 1 materials are designated for general-purpose use and Class 2 materials are high-strength compounds. The grades for MIL-DTL-25988 fluorosilicones correspond to the material’s durometer.

The table below describes the MIL-DTL-25988 fluorosilicones that Elasto Proxy can fabricate for you.

Type

Class

Grade

2

2

70

2

1

60

1 & 2

2

70

2

1

40

2

1&2

50

2

1

80

  

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Aerospace Silicones and Fluorosilicones from Elasto Proxy

At our headquarters near Montreal, Quebec, Canada, Elasto Proxy’s fabricates AA 59588 silicones, AMS silicones and MIL-DTL-25988 fluorosilicones into aerospace parts from sheets, rolls, and extrusions. We can store your materials or finished goods at our Montreal-area warehouse, or at our facility near Toronto. Elasto Proxy is also bringing aerospace silicone products to U.S. customers through our branch in Simpsonville, South Carolina.   

Elasto Proxy’s quality management system (QMS) is AS 9100 D certified and we operate four locations with clearly-defined scopes under ISO 9001:2015, upon which AS 9100D is based. For molded silicone aerospace parts, we’ve partnered with an AS 9100D certified molder. If you need silicone aerospace parts low-to-medium volumes, we invite you to contact us. With the strength of our supply chain, we can offer these materials in lower minimum order quantities (MOQs) than you might expect.

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