Atom
Type	Piston aircraft engine
National origin	Czechoslovakia
Manufacturer	Walter Aircraft Engines
First run	1934

The Walter Atom is an air-cooled horizontal two-cylinder engine used on light aircraft. The Atom is a Czechoslovakian engine first produced in 1934.

Specifications (Atom)

General characteristics

• Type: Horizontally-opposed 2 cylinder air-cooled
• Bore: 85 mm (3.35 in)
• Stroke: 96 mm (3.78 in)
• Displacement: 1.09 L (66.5 cu in)
• Length: 510 mm (20.08 in)
• Width: 815 mm (32.09 in)
• Height: 409 mm (16.10 in)
• Dry weight: 40 kg (88.2 lb)

Components

• Valvetrain: 1 inlet and one exhaust valve per cylinder
• Fuel system: 2 Amal carburettors
• Fuel type: 68 octane
• Cooling system: air

Performance

• Power output: 21 kW (28 hp) at 3000 RPM
• Compression ratio: 5.2:1
• Power-to-weight ratio: 2.14 kg/kW (3.52 lb/hp) at cruise