# Sopwith L.R.T.Tr. > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Sopwith_L.R.T.Tr. > Markdown URL: https://mediated.wiki/source/Sopwith_L.R.T.Tr..md > Source: https://en.wikipedia.org/wiki/Sopwith_L.R.T.Tr. > Source revision: 1321135869 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) British WW1 triplane escort fighter aircraft L.R.T.Tr. General information Type Escort fighter National origin United Kingdom Manufacturer Sopwith Status Prototype Number built 1 History First flight 1916 The **Sopwith Long Range Tractor Triplane** (L.R.T.Tr) was a prototype [British](/source/United_Kingdom) long-range three-seat [triplane](/source/Triplane) escort fighter of the [First World War](/source/First_World_War). Its unusual layout had a small gunner's [nacelle](/source/Nacelle) mounted on the upper wing for an all-round field of fire. Only a single example was built, as other, smaller fighters proved more practicable. ## Development and design In early 1916, the British [War Office](/source/War_Office) drew up a specification for a multi-seat escort fighter to be powered by one of the new [Rolls-Royce Eagle](/source/Rolls-Royce_Eagle) engines, intended to protect formations of bombers from German fighters, with an additional role of destroying enemy [airships](/source/Airship).[1] While the specification did not require high speed, a good field of fire for its guns was essential,[2] while the secondary anti-Zeppelin role demanded an endurance of at least seven hours.[1] Orders were placed for prototypes from [Armstrong Whitworth](/source/Armstrong_Whitworth_Aircraft) (the [F.K.6](/source/Armstrong_Whitworth_F.K.6)), [Sopwith](/source/Sopwith_Aviation_Company) and [Vickers](/source/Vickers_Limited) (the [F.B.11](/source/Vickers_F.B.11)). All three designs were driven by the need to provide wide fields of fire in the absence of an effective [synchronisation gear](/source/Synchronization_gear) that would allow safe firing of guns through the propeller disc.[1] The Sopwith proposal was modified from an existing design for a two-seat [triplane](/source/Triplane), with a nacelle for a gunner added to the upper wing.[3] It had three-bay, narrow chord wings, with the streamlined nacelle housing the upper gunner who was armed with a [Lewis gun](/source/Lewis_gun) built around the centre section of the upper wing.[4] [Ailerons](/source/Aileron) were fitted to all wings, with [air brakes](/source/Air_brake_(aircraft)) fitted to the lower wing. The deep [fuselage](/source/Fuselage) housed the pilot and a second gunner to guard the aircraft's tail.[5] Balancing wheels were fitted well ahead of the aircraft's mainwheels in order to prevent the aircraft overturning, as the upper gunner would be extremely vulnerable if this occurred.[6] The prototype, which was nicknamed "Egg-Box",[7] flew late in 1916.[5] It was not developed further, with smaller fighters fitted with [synchronisation gear](/source/Synchronization_gear) such as Sopwith's own [1½ Strutter](/source/Sopwith_1%C2%BD_Strutter) now available, with all of the proposed three-seat escort fighters abandoned.[8] ## Specifications (L.R.T.Tr.) *Data from* War Planes of the First World War:Volume Two Fighters [9] **General characteristics** - **Crew:** 3 (pilot and 2 gunners) - **Length:** 35 ft 3 in (10.74 m) - **Height:** 52 ft 9 in (16.08 m) - **Powerplant:** 1 × [Rolls-Royce Eagle](/source/Rolls-Royce_Eagle) water-cooled [V12 engine](/source/V12_engine), 250 hp (190 kW) **Performance** - **Maximum speed:** 107 mph (172 km/h, 93 kn) (approx.)[10] **Armament** - **Guns:** - 1× [.303 in](/source/.303_British) (7.7 mm) [Lewis gun](/source/Lewis_gun) in nacelle - 1× Lewis gun in rear cockpit ## See also **Aircraft of comparable role, configuration, and era** - [Armstrong Whitworth F.K.6](/source/Armstrong_Whitworth_F.K.6) - [Vickers F.B.11](/source/Vickers_F.B.11) ## Notes 1. ^ [***a***](#cite_ref-bruce1957p25_1-0) [***b***](#cite_ref-bruce1957p25_1-1) [***c***](#cite_ref-bruce1957p25_1-2) Bruce 1957, p. 25. 1. **[^](#cite_ref-2)** Mason 1992, p. 67. 1. **[^](#cite_ref-3)** Bruce 1968, pp. 139–140. 1. **[^](#cite_ref-4)** Bruce 1968, p. 140. 1. ^ [***a***](#cite_ref-mason78_5-0) [***b***](#cite_ref-mason78_5-1) Mason 1992, p. 78. 1. **[^](#cite_ref-6)** Bruce 1968, p. 141. 1. **[^](#cite_ref-7)** Green and Swanborough 1994, p. 535. 1. **[^](#cite_ref-8)** Lewis 1979, p. 99. 1. **[^](#cite_ref-9)** Bruce 1968, p. 142. 1. **[^](#cite_ref-10)** Mason 1992, p. 79. ## References - Bruce, J. M. *British Aeroplanes 1914-18*. London: Putnam, 1957. - Bruce, J. M. *War Planes of the First World War: Volume Two Fighters*. London: Macdonald, 1968. [ISBN](/source/ISBN_(identifier)) [0-356-01473-8](https://en.wikipedia.org/wiki/Special:BookSources/0-356-01473-8). - Green, William, and Swanborough, Gordon. *The Complete Book of Fighters*. New York: Smithmark, 1994. [ISBN](/source/ISBN_(identifier)) [0-8317-3939-8](https://en.wikipedia.org/wiki/Special:BookSources/0-8317-3939-8). - Lewis, Peter. *The British Fighter since 1912*. London: Putnam, Fourth edition, 1979. [ISBN](/source/ISBN_(identifier)) [0-370-10049-2](https://en.wikipedia.org/wiki/Special:BookSources/0-370-10049-2). - Mason, Francis K. *The British Fighter since 1912*. Annapolis, Maryland, USA: Naval Institute Press, 1992. [ISBN](/source/ISBN_(identifier)) [1-55750-082-7](https://en.wikipedia.org/wiki/Special:BookSources/1-55750-082-7). v t e Sopwith aircraft By role Fighters Buffalo Bulldog Camel Dolphin Dragon Gunbus Hippo Hispano-Suiza Triplane L.R.T.Tr. Pup Snail Snapper Snark Snipe Swallow Triplane Bombers B.1 Cobham Rhino Torpedo bomber Cuckoo Scouts/bombers Baby Sparrow 1½ Strutter Tabloid Two-Seat Scout Seaplanes Bat-Boat Circuit of Britain floatplane Sopwith Pusher Seaplane/S PG N Admiralty Type 137 Admiralty Type 138 Admiralty Type C Special torpedo seaplane Type C Type 807 Type 860 Schneider (1914) Baby Schneider (1919) Ground attack Salamander Sports tourer Gnu By designation B.1 B.2 2B.2 F.1 2F.1 4F.1 5F.1 7F.1 8F.1 3F.2 (I) 3F.2 (II) FR.2 2FR.2 FS.1 T.1 TF.1 TF.2 By name Antelope Atlantic Baby Bat-Boat Bee Buffalo Bulldog Circuit of Britain floatplane Camel Cobham Cuckoo Dolphin Dove Dragon Gnu Grasshopper Gunbus Hippo Hispano-Suiza Triplane L.R.T.Tr. Pup Rainbow Rhino Salamander Scooter Snail Snapper Snark Snipe Sparrow Sociable Swallow 1½ Strutter Tabloid Tadpole Three-seater Triplane Special torpedo seaplane Type C Wallaby Designers Herbert Smith Thomas Sopwith --- Adapted from the Wikipedia article [Sopwith L.R.T.Tr.](https://en.wikipedia.org/wiki/Sopwith_L.R.T.Tr.) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Sopwith_L.R.T.Tr.?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.