The Continental A40 engine is a carbureted four-cylinder, horizontally opposed, air-cooled aircraft engine that was developed especially for use in light aircraft by Continental Motors. It was produced between 1931 and 1941.[1][2][3]
Design and development
The 37 hp (28 kW) A40 was introduced in the depths of the Great Depression. At the time there were a number of small engines available but all suffered from either high cost, complexity, or low reliability. The A-40 addressed all those shortcomings and was instrumental in the production of light aircraft in the difficult economic constraints of the period. The A-40-4 introduced an increase in power to 40 hp (30 kW). The engine later inspired the A-50 and subsequent engines.[1][2][4]
The A40 featured single ignition until the A-40-5 version, which introduced dual ignition. All engines in this family have a 5.2:1 compression ratio and were designed to run on fuel with a minimum octane rating of 73.[2][3]
The entire family of engines had its certification terminated on 1 November 1941. Engines produced before that date are still certified, but none can be produced after that date.[2][3]
Variants
A40
Single ignition, 37 hp (28 kW) at 2550 rpm, dry weight 144 lb (65 kg)[2]
A40-2
Single ignition, 37 hp (28 kW) at 2550 rpm, dry weight 144 lb (65 kg)[2]
A-40-3
Single ignition, 37 hp (28 kW) at 2550 rpm, dry weight 144 lb (65 kg)[2] Featured cadmium-nickel connecting rod bearings.[5]
A40-4
Single ignition, 40 hp (30 kW) at 2575 rpm, dry weight 144 lb (65 kg),[2] Steel backed connecting rod inserts
A40-5
Dual ignition, 40 hp (30 kW) at 2575 rpm, dry weight 156 lb (71 kg)[3]
