AVGAS ratings

[megan]

There is an error in that Shell info sheet. The method is ASTM D 909, not 910

The Shell sheet is correct, ASTM D909 merely gives the rich mixture knock value, the overarching spec is ASTM D910. The 910 specification does not include all gasoline satisfactory for reciprocating aviation engines, but rather, defines the following specific types of aviation gasoline for civil use: Grade 80; Grade 91; Grade 100; and Grade 100LL. The gasoline shall adhere to octane rating requirements specified for individual grades, as follows: lean mixture knock value (motor octane number and aviation lean rating); rich mixture knock value (octane and performance number); tetraethyl lead content; color; and dye content (blue, yellow, red, and orange). Conversely, the gasoline shall meet the following requirements specified for all grades: density; distillation (initial and final boiling points, fuel evaporated, evaporated temperatures); recovery, residue, and loss volume; vapor pressure; freezing point; sulfur content; net heat of combustion; copper strip corrosion; oxidation stability (potential gum and lead precipitate); volume change during water reaction; and electrical conductivity. The following sub part requirements,

Test specification for aviation gasoline: ASTM D910

Avgas fuel test: ASTM tests:

Motor Octane Number ASTM D2700
Aviation Lean Rating ASTM D2700
Performance Number (Super-Charge) ASTM D909
Tetraethyl Lead ASTM D5059
Color ASTM D2392
Density ASTM D4052
Distillation ASTM D86
Vapor Pressure ASTM D5191
Freezing Point ASTM D2386
Sulfur ASTM D2622
Net Heat of Combustion ASTM D3338
Copper Corrosion ASTM D130
Oxidation Stability - Potential Gum ASTM D873
Oxidation Stability - Lead Precipitate ASTM D873
Water Reaction - Volume change ASTM D1094
Electrical Conductivity ASTM D2624