The Lycoming O-435 is an American six-

cylinder A cylinder (from ) has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infin ...

horizontally opposed A flat engine is a piston engine where the cylinders are located on either side of a central crankshaft. Flat engines are also known as horizontally opposed engines, however this is distinct from the less common opposed-piston engine design, wh ...

fixed-wing aircraft A fixed-wing aircraft is a heavier-than-air flying machine, such as an airplane, which is capable of flight using wings that generate lift caused by the aircraft's forward airspeed and the shape of the wings. Fixed-wing aircraft are distinc ...

and

helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes ...

engine made by

Lycoming Engines Lycoming Engines is a major American manufacturer of aircraft engines. With a factory in Williamsport, Pennsylvania, Lycoming produces a line of horizontally opposed, air-cooled, four, six and eight-cylinder engines including the only FAA-certi ...

. The engine is a six-cylinder version of the four-cylinder

Lycoming O-290 Lycoming may refer to the following, most of which are at least partly in Lycoming County, Pennsylvania, United States: Geography * Lycoming, New York, a hamlet * Lycoming County, Pennsylvania * Lycoming Township, Lycoming County, Pennsylvania * Ly ...

Design and development

The powerplant is a horizontally opposed Lycoming six-cylinder design. It is a direct-drive or geared, air-cooled, and normally aspirated engine. The cylinders have steel barrels with aluminum heads, and the valves are operated by hydraulic lifters. The crankshaft is supported in an aluminum-alloy split case by four main bearings and one ball-thrust bearing, and lubricating oil is supplied from a 12 quart wet sump. The camshaft rides in journals that do not employ bearing inserts. The accessory housing supports two magnetos, a starter, a generator, and a dual tach drive. A spare mounting pad is included for a vacuum pump.

Variants

All engines have an additional prefix preceding the ''435'' to indicate the specific configuration of the engine. There are also numerous engine suffixes, denoting different accessories such as different manufacturers' carburetors, or different

magneto A magneto is an electrical generator that uses permanent magnets to produce periodic pulses of alternating current. Unlike a dynamo, a magneto does not contain a commutator to produce direct current. It is categorized as a form of alternator, ...

O-435 models

;O-435 :Baseline engine model, producing at 2300 rpm, with a compression ratio of 6.25:1, a dry weight of and fitted with a Marvel MA-4 carburetor.

Type certified A type certificate signifies the airworthiness of a particular category of aircraft, according to its manufacturing design (''type design''). It confirms that the aircraft of a new type intended for serial production, is in compliance with applica ...

on February 11, 1942. ;O-435-A :Engine model with provisions for automotive type accessories, producing at 2550 rpm, with a compression ratio of 6.5:1, a dry weight of with a -8 magneto and with a -20 magneto and fitted with a Marvel MA-4-5 or PS-5C carburetor. Type certified on February 11, 1942. ;O-435-A2 :Engine model with a redesigned improved crankcase, cylinders, valves and valve seats, exhaust valve guides and rocker shaft bushing. It also has provisions for automotive-type accessories. It produced at 3000 rpm, with a compression ratio of 7.5:1, a dry weight of and fitted with a Marvel MA-4-5 carburetor. Type certified on October 19, 1949 and cancelled on February 25, 1944. ;O-435-A3 :Type certified on January 5, 1951 and cancelled on February 8, 1955. ;O-435-B (military designation O-435-5) :Engine model with provisions for AN type accessories, producing at 3000 rpm, with a compression ratio of 7.5:1, a dry weight of and fitted with a Marvel MA-4-5 carburetor. Type certified on October 7, 1943 and cancelled on November 2, 1950. ;O-435-C (military designation O-435-1) :Engine model with provisions for AN type accessories, producing at 2300 rpm, with a compression ratio of 6.25:1, a dry weight of and fitted with a Marvel MA-4SPA carburetor. Type certified on January 11, 1943. ;O-435-C1 (military designation O-435-11) :Engine model, with revised type valves, valve guides, an accessory case with generator and starter drive, producing at 2300 rpm, with a compression ratio of 6.25:1, a dry weight of and fitted with a Marvel MA-4 carburetor. Type certified on January 2, 1948. ;O-435-C2 (military designation O-435-13) :Engine model, with provisions for O-435-C accessories carburetor, producing at 2300 rpm, with a compression ratio of 6.25:1, a dry weight of and fitted with a Marvel MA-4SPA carburetor. Type certified on January 2, 1948. ;O-435-K :Engine model that incorporates a GO-435-C2 accessory case and crankcase. It produces at 3000 rpm, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 carburetor. Type certified on January 24, 1951. ;O-435-K1 (military designation O-435-4) :Engine model with increased maximum continuous rating and the generator pad omitted, approved for helicopter installations. It produces at 3000 rpm, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 carburetor. Type certified on March 30, 1951. ;O-435-2 :Military engine model. ;O-435-2-M1 :Civil modified military engine model, by the Associated Aircraft Modification Company, with Bendix PS-5C carburetor with 380123-1 setting. It produces at 3200 rpm, with a compression ratio of 7.5:1, a dry weight of . Only military O-435-2 engines with serial numbers L00849-11 through L-1117-11 are eligible for this modification.

GO-435 models

;GO-435 :Baseline geared engine model. It incorporates six 3rd-order crankshaft torsional vibration dampers and reduction gearing. It produced at 3000 rpm, with a compression ratio of 6.25:1, a dry weight of and fitted with a Marvel MA-4-5 carburetor. Type certified on August 30, 1944 and cancelled on November 2, 1950. ;GO-435-A2 :Type certified on October 19, 1949 and cancelled on February 8, 1955. ;GO-435-C2 (military designation O-435-17) :Geared engine model which incorporates an improved crankcase and cylinder assembly. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on October 19, 1949. ;GO-435-C2A :Geared engine model, incorporates S6LN-20 or -21 magnetos, producing at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on January 2, 1951, cancelled on February 8, 1955 and reinstated July 15, 1955. ;GO-435-C2A2 :Geared engine model, with a dry sump and without provisions for a hydraulic propeller control or governor, producing at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on October 24, 1957. ;GO-435-C2B :Geared engine model with provisions for a hydraulic propeller and governor. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on November 6, 1952. ;GO-435-C2B1 :Geared engine model which incorporates a dual generator and vacuum pump drive. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on February 8, 1955. ;GO-435-C2B2 :Geared engine model with S6LN-20, or -21 magnetos. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on February 28, 1956. ;GO-435-C2C :Geared engine model producing at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on November 24, 1953 and cancelled on July 5, 1956. ;GO-435-C2D :Geared engine model producing at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on July 20, 1954 and cancelled on July 5, 1956. ;GO-435-C2E :Geared engine model with S6LN-20, or -21 magnetos. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on September 27, 1956. ;GO-435-D1 :Geared engine model with a dry sump oil system and crosswise accessory drives. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1 and fitted with a Marvel MA-4-5 or PS-5BD carburetor. Type certified on September 25, 1953.

VO-435 models

;VO-435 :Base model, vertically-mounted engine for helicopters, with a dry sump oil system and side-mounted AN type accessory drives. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or MA-4-5AA carburetor. Type certified on October 11, 1954. Was re-designated as VO-435-A1A. ;VO-435-A1A (military designation O-435-21) :Vertically-mounted engine model for helicopters, with a dry sump oil system and side-mounted AN type accessory drives. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or MA-4-5AA carburetor. Type certified on October 29, 1954. Re-designated from VO-435. ;VO-435-A1B (military designation O-435-6) :Vertically-mounted engine model for helicopters, with a dry sump oil system and a modified accessory section. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or MA-4-5AA carburetor. Type certified on June 10, 1955. ;VO-435-A1C (military designations O-435-23, O-435-23A O-435-23B and O-435-23C) :Vertically-mounted engine model for helicopters, with a dry sump oil system, which incorporates a crankcase and oil sump modification giving increased strength and an oil pump housing which is machined for a hydraulic pump drive. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or MA-4-5AA carburetor. Type certified on July 18, 1954. ;VO-435-A1D (military designation O-435-6A) :Vertically-mounted engine model for helicopters, with a dry sump oil system, with crankcase and oil sump modifications for increased strength. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5 or MA-4-5AA carburetor. Type certified on September 27, 1956. ;VO-435-A1E :Vertically-mounted engine model for helicopters, with a dry sump oil system and 6RN-200 or S6LN-204 magnetos. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5AA carburetor. Type certified on October 15, 1959. ;VO-435-A1F :Vertically-mounted engine model for helicopters, with a dry sump oil system. It has internal piston cooling oil jets and heavy duty cylinders and may be converted to a model TVO-435-A1A. It produces at 3400 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel MA-4-5AA carburetor. Type certified on March 6, 1961. ;VO-435-B1A :Vertically-mounted engine model for helicopters, with a redesigned accessory drive section, a wet oil sump and a higher compression ratio. It produces at 3200 rpm for takeoff, with a compression ratio of 8.7:1, a dry weight of and fitted with a Marvel MA-4-5AA carburetor. Type certified on December 15, 1965. ;TVO-435-A1A :

Turbocharged In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...

TVO-435 models

;TVO-435-A1A :

, vertically-mounted engine model for helicopters, with a dry sump oil system. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on May 12, 1961. ;TVO-435-B1A (military designation O-435-25A) :Turbocharged, vertically-mounted engine model with internal piston cooling oil jets, for helicopters, with a dry sump oil system and cylinder assemblies machined for long-reach spark plugs. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on November 21, 1962. ;TVO-435-B1B :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system and TCM (formerly Bendix) S6RN-1208 and S6LN-1209 magnetos. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on June 20, 1966. ;TVO-435-C1A :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system and a T-1112 turbosupercharger. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on November 21, 1962. ;TVO-435-D1A :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system. It has a TK-0659 turbocharger and TCM (formerly Bendix) S6RN-1208 (retarded breaker) and S6LN-1209 magnetos. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on March 10, 1966. ;TVO-435-D1B :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system. It has TCM (formerly Bendix) S-200 series magnetos. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on February 23, 1967. ;TVO-435-E1A :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system and a Kelly Aerospace (formerly AiResearch) TK-0659 turbocharger. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on March 7, 1967. ;TVO-435-F1A :Turbocharged, vertically-mounted engine model for helicopters, with a wet sump oil system, different accessory section and a higher power rating. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on January 22, 1968. ;TVO-435-G1A :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system and a different automatic waste gate control setting for a higher power rating. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on January 11, 1968. ;TVO-435-G1B :Turbocharged, vertically-mounted engine model for helicopters, with a dry sump oil system and different magnetos. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on November 25, 1968. ;TVO-435-25 :Turbocharged, vertically-mounted military engine model for helicopters, with a dry sump oil system. This military model is similar to the -A1A, except it has cylinder assemblies from the -B1A. It produces at 3200 rpm for takeoff, with a compression ratio of 7.3:1, a dry weight of and fitted with a Marvel-Schebler MA-6AA carburetor. Type certified on June 10, 1963.

Applications

;Aircraft ;Other *

M22 Locust The M22 Locust, officially Light Tank (Airborne), M22, was an American-designed airborne light tank which was produced during World War II. The Locust began development in 1941 after the British War Office requested that the American government d ...

- tank

Specifications (O-435-D)

References

Notes

Bibliography

* Bridgman, Leonard. ''Jane's All the World's Aircraft 1945-46.'' Hammersmith, London: HarperCollinsPublishers (1994 reprint).

External links

* {{Lycoming aeroengines O-438 Boxer engines 1940s aircraft piston engines