Bristol Mercury 147260 224971627 2008-07-11T06:54:51Z AMCKen 4484456 /* Specifications (Mercury XV) */ <!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. --> [[image:bristol.mercury.arp.750pix.jpg|thumb|right|Bristol Mercury engine]] [[Image:Bristol (NOHAB) Mercury.jpg|thumb|Mercury built by [[NOHAB]]]] [[Image:Bristol Mercury.jpg|thumb|Bristol Mercury engine]] The '''Bristol Mercury''' was a 9-cylinder one-row piston [[radial engine]] used on British aircraft in the 1930s and 1940s. ==History== The '''Mercury''' was developed by the [[Bristol Aeroplane Company]] in [[1925 in aviation|1925]] as their [[Bristol Jupiter]] was reaching the end of its lifespan. Although the Mercury initially failed to attract much interest, the [[Air Ministry]] eventually funded three prototypes and it became another winner for the designer [[Roy Fedden]]. With the widespread introduction of [[supercharger]]s to the aviation industry in order to improve altitude performance, Fedden felt it was reasonable to use a small amount of boost at all times in order to improve performance of an otherwise smaller engine. Instead of designing an entirely new block, the existing Jupiter parts were re-used with the stroke reduced by one inch (25 mm). The now-smaller capacity engine was then boosted back to Jupiter power levels, while running at higher rpm and thus requiring a reduction gear for the [[propeller]]. The same techniques were applied to the original Jupiter-sized engine to produce the [[Bristol Pegasus|Pegasus]]. The Mercury's smaller size was aimed at [[fighter aircraft|fighter]] use, and it powered the [[Gloster Gauntlet]] and its successor, the [[Gloster Gladiator]]. It was intended that the larger Pegasus would be for [[bomber aircraft|bomber]]s, but as the power ratings of both engines rose the Mercury found itself being used in almost all roles. Perhaps its most famous use was in a twin-engine [[light bomber]], the [[Bristol Blenheim]]. Outside the United Kingdom, Mercury was licence-built in Poland and used in their [[PZL P.11]] fighters. It was also built by [[NOHAB]] in Sweden and used in the Swedish Gloster Gladiator fighters and in the [[Saab 17]] dive-bomber. In Italy, it was built by [[Alfa Romeo]] as the Mercurius. ==Variants== * '''Mercury VIII''' - 730 hp (545 kW) at 2,650 rpm for takeoff, 840 hp (625 kW) at 2,750 rpm maximum continuous power * '''Mercury XV''' - 840 hp (625 kW) at 2,750 rpm at 14,000 ft (4,270 m) maximum power with 87-[[octane rating|octane]] fuel; 995 hp (740 kW) at 2,750 rpm at 9,250 ft (2,820 m) maximum power with 100-octane fuel * '''Mercury XX''' - 870 hp (650 kW) at 2,650 rpm at 4,500 ft (1,370 m) maximum power ==Specifications (Mercury XV)== {{pistonspecs| <!-- If you do not understand how to use this template, please ask at [[Wikipedia talk:WikiProject Aircraft]] --> <!-- Please include units where appropriate (main comes first, alt in parentheses). If data are missing, leave the parameter blank (do not delete it). For additional lines, end your alt units with </li> and start a new, fully-formatted line with <li> --> |type=9-cylinder supercharged air-cooled [[radial engine]] |bore=5.75 in (146 mm) |stroke=6.5 in (165 mm) |displacement=1,519.09 in³ (24.89 L) |length= |diameter=51.5 in (1.307 m) |width= |height= |weight=1,065 lb (485 kg) |valvetrain=Four [[pushrod]]-actuated valves per cylinder, two inlet and two [[sodium]]-cooled exhaust valves |supercharger=High-speed centrifugal, single-stage single-speed |turbocharger= |fuelsystem=[[Claudel-Hobson]] [[carburetor]] with automatic boost and mixture control |fueltype=87- or 100-[[octane rating|octane]] gasoline |oilsystem=[[Dry sump]] with one combination pressure/scavenge pump |coolingsystem= |power=<br> *840 hp (625 kW) at 2,750 rpm at 14,000 ft (4,270 m) maximum power with 87-[[octane rating|octane]] fuel *995 hp (740 kW) at 2,750 rpm at 9,250 ft (2,820 m) maximum power with 100-octane fuel |specpower=0.65 hp/in³ (29.7 kW/L) with 100-octane fuel |compression=7:1 |fuelcon= |specfuelcon=1.0 lb/(hp·h) (0.61 kg/(kW·h)) |oilcon= |power/weight=0.93 hp/lb (1.53 kW/kg) }} ==Applications== ;{{GBR}}: *[[Airspeed Cambridge]] *[[Bristol Blenheim]] *[[Breda Ba.27]] {{ITA}} *[[Fokker D XXI]] {{NED}} *[[Fokker G.1]] {{NED}} *[[Gloster Gladiator]] *[[Gloster Gauntlet]] *[[IMAM Ro.30]] {{ITA}} *[[Miles Martinet]] *[[Miles Master]] *[[PZL P.11]] {{POL}} *[[Saab 17]] {{SWE}} *[[Supermarine Sea Otter]] *[[Valmet Vihuri]] {{FIN}} *[[Westland Lysander]] ==References== * Bridgman, L, (ed.) (1998) ''Jane's fighting aircraft of World War II.'' Crescent. ISBN 0-517-67964-7 ==See also== * [[Bristol Jupiter]] * [[Bristol Pegasus]] ==External links== * [http://republika.pl/rola1/files/pzl11_start_run_01.mp3 Recorded sound of the Mercury V S2 engine] used in [[PZL P.11c]] (mp3 format) ==See also== ''The '''Bristol Mercury''' was also a [[newspaper]] from [[Bristol]], published in the 1800s.'' {{BristolAeroengines}} [[Category:Radial engines]] [[Category:Aircraft piston engines]] [[cs:Bristol Mercury]] [[de:Bristol Mercury]] [[it:Bristol Mercury]] [[hu:Bristol Mercury]]