Curtiss V-1570 Conqueror
	The Curtiss V-1570 Conqueror.
	The Curtiss V-1570 Conqueror was an offspring of the Curtiss D-12. The D-12 was the first engine to ever power a plane to 200 mph.
The Conqueror had a displacement of 1,570 cu. in. that featured open ended cylinder liners which was advanced technology at the time. It used a pressurized liquid cooling system with a mixture of ethylene glycol, but the system ran hot at 300 degrees F. The high temperatures, as specified by the US Army, made the engine temperamental and prone to burning valves at a moment’s notice. Developments included the use of a supercharger which gradually increased power output, but reliability problems persisted. The Conqueror was more expensive than air-cooled radials and despite the radials decreased performance in altitude, range and airspeed, military funding for the Conqueror was cut in 1932.
	Curtiss-Wright tried marketing the engine for civilian airliners by way of the Curtiss B-2 Condor, but the effort was half-hearted and when the venture flopped, Curtiss-Wright got out of the liquid-cooled engine business for good. 1

Specifications:
Curtiss V-1570 Conqueror
Date:	1928
Cylinders:	12
Configuration:	Vee-inline, liquid-cooled
Horsepower:	600 hp (447 kw)
RPM:	2,400
Bore and Stroke:	5.1 in. (130 mm) x 6.2 in. (159 mm)
Displacement:	1,570 cu. in. (25.7 liters)
Weight:	770 lbs. (349 kg)

Endnotes:

1. Herschel Smith. A History of Aircraft Piston Engines. Manhattan, Kansas: Sunflower University Press, 1993. 70-76.