page_title: Stinson L-5 Sentinel
section_title: Variants
hierarchical_section_title: Stinson L-5 Sentinel / Variants
caption_attribution_description: English: L-5E Sentinel
context_page_description: The Stinson L-5 Sentinel was a World War II era liaison aircraft used by all branches of the U.S. military and by the British Royal Air Force. It was produced by the Stinson Aircraft Company. Along with the Stinson L-1 Vigilant, the L-5 was the only other American liaison aircraft of World War II that was purpose-built for military use and had no civilian counterpart. All other military liaison airplanes adopted during World War II were lightly modified "off-the-shelf" civilian models.
context_section_description: Five versions of the Sentinel were produced for the U.S. Army Air Force (USAAF); the L-5, L-5B, L-5C, L-5E and L-5G. There was no official L-5A variant as is often reported because the designation was intended for a version of the aircraft that was never built. Nonetheless, many people in and out of the military still refer to the standard "observer" version of the L-5 as an L-5A. Like the L-5A, the L-5D was a planned version that was not adopted. A single L-5F was an L-5B equipped with an experimental low-noise "stealth" propeller and exhaust system for research purposes. The L-5B through L-5G models were modified to carry a litter patient or light cargo, or a rear seat passenger sitting in the normal position. An L-5H version was on the drawing boards at Stinson when the war ended, and it never reached the prototype stage.
  O-62
  Observation, artillery spotting and liaison aircraft, powered by a Lycoming 0-435-1 piston engine; 275 built.
  L-5
  Observation, artillery spotting and liaison aircraft; 1,538 built, 79 transferred to USN/USMC as OY-1.
  L-5A
  Cancelled conversions of L-5 with 24V electrical system and 200 hp ranger engine.
  L-5B
  729 aircraft with rear fuselage hatch to permit loading of a stretcher or cargo; twin-float capability; 60 transferred to RAF as Sentinel Mk II, 40 transferred to USN/USMC as OY-1.
  L-5C
  200 L5-B were equipped K-20 reconnaissance cameras.
  L-5D
  Not adopted. No prototype built.
  L-5E
  750 STOL variants with larger tires and brakes and manually drooping ailerons allowing shorter takeoff and landing; 152 transferred to USN/USMC as OY-1. An L-5E-1 variant included larger wheels and tires and heavy duty brakes. Thirty L-5E's were later converted to 24 volt electrical systems and re-designated OY-2.
  L-5G
  Similar to L-5E but with a 24 volt electrical system and powered by 190-hp (142-kW) Lycoming 0-435-11 piston engine with improved cylinders and carburetor and fitted with controllable pitch propellers. 115 were built by end of the war and the contract for 785 others was cancelled. Final production model redesignated U-19B in 1962.
  XL-5F
  One test and evaluation aircraft, powered by a Lycoming 0-435-2 piston engine.
  U-19A
  L-5 variants still in service redesignated U-19A by the USAF in 1962.
  U-19B
  L-5G redesignated U-19B in 1962. One used as a glider tug at the [United States Air Force Academy].
  OY-1
  306 L-5 and L-5Bs transferred to the United States Marine Corps and United States Navy.
  OY-2
  152 transfers of L-5E to USN/USMC; 30 OY-1 conversions to 24V electrical system.
  Sentinel Mk I
  40 L-5s supplied to the RAF under Lend-Lease.
  Sentinel Mk II
  60 L-5Bs supplied to the RAF under Lend-Lease.
  L-5/235
  variant powered by Lycoming O-540-B, 235 hp, used for glider towing.
caption: L-5E with "Quiet Flight" modifications at Langley
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