The Packard 1A-1500 was an American 12-cylinder liquid-cooled 60-degree Vee piston aircraft engine designed in 1924.^[1] Test flown in the second prototype Douglas XO-2 it proved to be unreliable. Only 29 engines were built.

Applications

• Boeing Model 15
• Boeing XP-4
• Curtiss Falcon
• Douglas XO-2
• Loening OL

Specifications (1A-1500)

Data from STATISTICS OF ALL THE AERO ENGINES OF PACKARD^[2]

General characteristics

• Type: V-12 liquid-cooled piston aircraft engine
• Bore: 5+3⁄8 in (136.5 mm)
• Stroke: 5+1⁄2 in (139.7 mm)
• Displacement: 1,498 in³ (24.5 L)
• Dry weight: 720 lb (326.5 kg)

Components

• Valvetrain: Four valves per cylinder, overhead camshaft
• Cooling system: Liquid-cooled

Performance

• Power output: 500 hp (370 kW) at 2,000 rpm maximum continuous;520 hp (390 kW) at 2,200 rpm for takeoff
• Specific power: 0.347 hp/cu in (15.8 kW/L)
• Power-to-weight ratio: 0.722 hp/lb (1.187 kW/kg)