# Lycoming R-680 > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Lycoming_R-680 > Markdown URL: https://mediated.wiki/source/Lycoming_R-680.md > Source: https://en.wikipedia.org/wiki/Lycoming_R-680 > Source revision: 1348619092 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) 1920s American aircraft piston engine R-680 Lycoming R-680 Type Piston aero-engine National origin United States Manufacturer Lycoming Engines First run 1929 Major applications Beechcraft AT-10 Wichita Stinson Reliant Curtiss-Wright AT-9 Stinson Airliner Manufactured 1930–1945 out of production Number built over 26.000 The **Lycoming R-680** is a nine-cylinder air-cooled [radial](/source/Radial_engine) engine, the first aero engine produced by [Lycoming](/source/Lycoming_Engines). The engine was produced in two types, the E and B series; both are essentially the same. The B4E was available in a trainer version with a front exhaust collector "ring" for use without cylinder air baffles. R-680 received Approved Type Certificate No. 42 on 4 Feb 1930. ## Variants **R-680** - Rated at 210 hp (160 kW) at 2,000 rpm. **R-680B4E** - Rated at 225 hp (168 kW) at 2,100 rpm.[1] **R-680BA** - Rated at 240 hp (180 kW) **R-680E3A** - Rated at 285 hp (213 kW) at 2,200 rpm.[1] **R-680-6** - Rated at 245 hp (183 kW) **R-680-9** - Rated at 300 hp (220 kW) at 2,200 rpm. **R-680-13** - Rated at 300 hp (220 kW) at 2,200 rpm.[1] ## Applications - [Beech AT-10 Wichita](/source/AT-10_Wichita) - [Boeing-Stearman PT-13](/source/Boeing-Stearman_Model_75) - [Cessna AT-8/AT-17](/source/Cessna_AT-17) - [Curtiss-Wright AT-9](/source/Curtiss-Wright_AT-9) - [Fleetwings BQ-2](/source/Fleetwings_BQ-2) - [Spartan NP-1](/source/Spartan_NP) - [Stinson Airliner](/source/Stinson_Airliner) - [Stinson Reliant](/source/Stinson_Reliant) - [Stinson L-1 Vigilant](/source/Stinson_L-1_Vigilant) - [Travel Air 4000](/source/Travel_Air_4000) - [Waco S Series](/source/Waco_S_Series) ## Specifications (R-680-E3A) *Data from* *Jane's Fighting Aircraft of World War II.*[1] ### General characteristics - **Type:** Nine-cylinder air-cooled radial - **[Bore](/source/Bore_(engine)):** 4 5⁄8 in (117 mm) - **[Stroke](/source/Stroke_(engine)):** 4 1⁄2 in (114 mm) - **[Displacement](/source/Engine_displacement):** 680 in³ (11.15 litres) - **Length:** 37.5 in (953.1 mm) - **Diameter:** 43.5 in (1104 mm) - **[Dry weight](/source/Dry_weight):** 515.46 lb (233.9 kg) ### Components - **[Valvetrain](/source/Valvetrain):** One inlet and one exhaust valve per cylinder at 30 degrees. - **Fuel system:** single-barrel carburetor - **Fuel type:** 87 [octane rating](/source/Octane_rating) [gasoline](/source/Gasoline) - **Oil system:** Full pressure type - **Cooling system:** Air-cooled ### Performance - **Power output:** 330 hp (246 kW) at 2,300 rpm at sea level - **[Compression ratio](/source/Compression_ratio):** 7:1 - **[Power-to-weight ratio](/source/Power-to-weight_ratio):** 0.64 hp/lb (1.05 kW/kg) ## See also **Comparable engines** - [Bristol Jupiter](/source/Bristol_Jupiter) - [Continental R-670](/source/Continental_R-670) - [Jacobs R-755](/source/Jacobs_R-755) - [Pratt & Whitney R-985](/source/Pratt_%26_Whitney_R-985) - [Wright R-790 Whirlwind](/source/Wright_R-790_Whirlwind) **Related lists** - [List of aircraft engines](/source/List_of_aircraft_engines) ## References Wikimedia Commons has media related to [Lycoming R-680](https://commons.wikimedia.org/wiki/Category:Lycoming_R-680). ### Notes 1. ^ [***a***](#cite_ref-janes_1-0) [***b***](#cite_ref-janes_1-1) [***c***](#cite_ref-janes_1-2) [***d***](#cite_ref-janes_1-3) Bridgman 1988 ### Bibliography - Bridgman, Leonard (1988). *Jane's Fighting Aircraft of World War II*. New York: Crescent Books. [ISBN](/source/ISBN_(identifier)) [0-517-67964-7](https://en.wikipedia.org/wiki/Special:BookSources/0-517-67964-7). v t e Lycoming aircraft engines Opposed piston engines O-145 O-233 IO-233 O-235 O-290 O-320 O-340 O-360 (O-360 variants) IO-390 O-435 O-480 O-540 TIO-541 GSO-580 IO-580 IO-720 O-1230 Radial engines and H engines R-680 XR-7755 XH-2470 Aircraft diesel engines DEL-120 Turbofans PLF1 ALF 502/YF102 LF 507 Turboprops/Turboshafts AGT1500 LTS101/LTP101 T53 T55 Aero-derivative marine gas turbines TF-40 Joint development Avco (Lycoming)/Pratt & Whitney: T800-APW (Turboshaft) See also AlliedSignal Aerospace/Honeywell Aerospace v t e United States military piston aircraft engine designation system H (four-bank H-configuration inline) H-1640 XH-2240 XH-2470 XH-2600 XH-3130 XH-3730 H-4070 IV (inverted-V inline) IV-1430 IV-2040 IV-2220 L (single-bank inline) L-330 L-365 L-375 L-390 L-410 L-440 L-510 L-825 O (opposed) O-15 O-40 O-45 O-90 O-100 O-145 O-150 O-170 O-175 O-180 O-190 O-200 (C) O-200 (F) O-205 O-235 O-290 O-300 O-335 O-360 (C) O-360 (L) O-405 O-425 O-435 O-470 O-480 O-520 O-540 (F) O-540 (L) O-550 O-580 O-805 O-1230 R (radial) R-250 R-265 R-270 R-370 (LB) R-370 (K) R-420 R-440 R-500 R-540 (W) R-540 (K) R-545 R-550 R-600 R-670 R-680 R-720 R-755 R-760 R-790 R-830 R-915 R-975 DR-980 R-985 R-1044 R-1300 R-1340 R-1454 R-1510 R-1535 R-1640 R-1670 R-1690 R-1740 R-1750 R-1820 R-1830 R-1860 R-2000 R-2060 R-2160 R-2180 R-2600 R-2800 R-3350 R-4090 R-4360 R-7755 V (upright-V inline) V-720 V-1150 V-1237 V-1400 V-1440 V-1460 V-1510 V-1560 V-1570 V-1650 (P) V-1710 V-1950 V-3420 V (inverted-V inline) V-770 V-1650 (L) VG (inverted-V inline) VG-1410 W (three-bank W-configuration inline) W-2779 See also: X-1800 US military gas turbine aeroengines Piston engine configurations --- Adapted from the Wikipedia article [Lycoming R-680](https://en.wikipedia.org/wiki/Lycoming_R-680) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Lycoming_R-680?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.