Stinson L 5 Sentinel performance and specifications

 

In 1939, Stinson entered the light-plane market with the Model 105. An improved Model 10 Voyager was introduced in 1941.

Six Model 10s were tested by the U.S. Army under the designation YO-54 and purchased with a more powerful engine as the O-62.

The O-62 designation was changed to the "L" for Liaison L-5 designation in 1942. 3,590 were ordered making the L-5 the second most widely used AAF liaison aircraft.

Almost 500 L-5s were transferred to the U.S. Navy and Marine Corps and received the designation OY-1.

The unarmed L-5 was used for reconnaissance, removing litter patients from front areas, delivering supplies to isolated units, laying communication wire, spotting targets, transporting personnel, rescuing personnel in remote areas and even as a light bomber.

In 1962 surviving L-5s were re-designated U-19 by the U.S. Air Force.

 

Weights and Loadings

Average Empty Weight

.............................................L-5 .........................1480 lbs.
.............................................L-5B .......................1520 lbs.
.............................................L-5C........................1540 lbs
.............................................L-5E: .......................1560 lbs
.............................................L-5G .......................1600 lbs

Standard Gross Weight

............................................L-5.......................... 2050 lbs.
............................................L-5B thru L-5E........ 2150 lbs.
............................................L-5G .......................2250 lbs.

Crew Capacity: 400 lbs
Cargo Capacity: 250 lbs (no passenger)
Wing Loading: 13.8 lb / sq. ft.

Engine

The powerplant is a horizontally opposed Lycoming 6-cylinder design. It is direct-drive, air-cooled, and normally aspirated. The cylinders have steel barrels with aluminium heads, and the valves are operated by hydraulic lifters. The crankshaft is supported in an aluminium-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.

Engine (L-5 thru L-5E)......................... Lycoming O-435-1
........................(L-5G)........................ Lycoming O-435-11Displacement....................................... 435 cubic inches
Compression Ratio.............................. 6.5 : 1
Maximum Rated Power (takeoff)......... 185 hp at 2550 rpm (O-435-1)
...........................................................190hp at 2550 rpm (O-435-11)
Normal Operating Range..................... 1900 - 2300 rpm
Induction............................................ Marvel-Schebler MA-4-5 carburettor
Fuel................................................... 73 or 80/85 octane.
Engine Weight.................................... 350 to 379 lbs.
Power Loading: .................................14.33 lb / hp

Propeller


Fahlin or Sensenich 85" diameter fixed-pitch wood
or
Koppers Aeromatic 220 85" diameter variable-pitch metal
or
Hartzell HC12x20-4..85" diameter variable-pitch metal

Fuselage


Fuselage construction is fabric over welded 4130 steel tubing and aluminium stringers. The doors are fabric covered plywood, and the boot cowl and engine cowlings are aluminium. The cantilevered main gear legs and tailwheel unit are welded steel and damped with oleo shock absorbers. The telescoping tailwheel oleo also employs a coil spring to prevent rapid bottoming of the strut.

Length: 24' 1.25"
Height: 7' 1"
Track: 7' 1"
Wheelbase: 18' 6"
Seating: Two in tandem

Wings


The wings are fabric covered and feature solid laminated wooden spars and built-up plywood ribs. All but the two outer ribs are identical. The leading and trailing edges are formed plywood, and the ply-sheeted bottoms act as shear panels, negating the need for internal bracing. The flaps and ailerons are a framework of aluminium covered with fabric, and the fixed leading edge slats are also aluminium. The flaps are a 3-position slotted type and manually operated by steel cables. The ailerons are actuated by a combination of cables in the fuselage and aluminium torque tubes in the wings.

Wing Span: 33' 11.62
Wing chord: 4' 9"
Wing dihedral: 2 1/2 degrees
Wing area: 155 sq. ft.
Airfoil: NACA 4412 (flat bottom)
Aileron span: 7' 6" each (total area 18.02 sq. ft.)
Flap span: 6' 8" each ( total area 12.22 sq. ft.)
Wing Slots: 3' 2" span each.

Basic Performance and Limitations


Maximum Level Speed................................. 128 mph at 2550 rpm
Maximum Dive Speed................................... 208 mph at 3050 rpm
Normal Climb Speed.................................... 85 mph at 2300 rpm
Normal Cruise Speed................................... 110 mph at 2250 rpm
Maximum Speed Flaps Extended.................. 100 mph
Stall Speed: (power-off, flaps up)...................57 mph
...................(power-on, flaps down)..............43 mph
Maximum Power Limitation.......................... 2550 rpm for 5 minutes
Service Ceiling..............................................15,600 ft.