S-38 Heron

S-38 Heron
File:S-38.png
Heron in flight over Dniegua
Role	Reconnaissance, Communications
National origin	Dniegua
Manufacturer	Aerotek
Designer	Yegor Lipmann
First flight	24 May 1938
Introduction	1938
Status	In service
Primary user	Dnieguan Armed Forces
Produced	1938-1976 (S-38 under Aerotek) 1976-2010 (under Rhinefeltaba Aeronomics)
Number built	6,500+
Unit cost	$32,000

The S-38 is a small liaison aircraft built by Aerotek of Ostragrad, Dniegua. Production has continued since 1938, and since 1980 mostly for the private market. It remains famous to this day for its excellent STOL performance; requiring less than 70 meters of unpaved runway to take off and land at full load. Versions of the S-38 have been armed for self defense and limited strike capabilities.

The S-38 has served the military and law enforcement community since 1939, making it the longest serving military aircraft, and has been on continuous production since 1938. Most of its current users are paramilitary forces and civilian pilots, though Dniegua acknowledges the S-38 has been used in operations against drug runners.

Design

The S-38 was conceived in 1936 following a request by Dniegua National Air Corps, requiring a sturdy, long range aircraft capable of taking off and landing on extremely short runways to preform medical evacuation, observation, army coordination, and a list of other operations. The resulting designs submitted eventually lead to one, designed by Yegor Lipmann, being chosen for initial small scale production. The aircraft was given the designation S-38, though Lipmann neglected to give the aircraft a model designation, calling it instead Heron.

A fixed slat ran along the entire length of the leading edge of the long wings, while a hinged and slotted set of control surfaces ran along the entire length of trailing edge. This was inspired by earlier 1930s "double-wing" aircraft wing control surface design. For the S-38 this setup along each wing panel's trailing edge was split nearly 50/50 between the inboard-located flaps and outboard-located ailerons, which themselves included trim tab devices over half of each aileron's trailing edge length. The S-38 used a small air frame with folding wings along the fuselage, allowing it to be loaded onto trailer or towed behind a vehicle slowly.

The primary hinge for the folding wing is located in the wing root, where the rear wing spar meets the cabin. The long legs of the main landing gear contained oil-and-spring shock absorbents that had a travel of 450 mm (18 inches), allowing the aircraft to land on comparatively rough and uneven surfaces. In flight, the landing gear legs hang down, giving the aircraft the appearance of a long-legged, big-winged bird, hence Lipmans name for the aircraft. With its very low landing speed the Heron often appears to land vertically, or even backwards, in strong winds from directly ahead.

The aircraft served well in the Dnieguan Air Force and Naval Aviation from 1939 to 1975, when it was retired. Despite the age of the aircrafts design, the aircraft has remained highly popular in many roles. In part, this is credited to its low operating cost, procurement cost, simplicity and high reliability. The S-38 has easy handling characteristics and is relatively simple to operate.

Specifications (S-38)

File:S-38 line.png

General characteristics

• Crew: 2
• Length: 9.9 m (32 ft 6 in)
• Wingspan: 14.3 m (46 ft 9 in)
• Height: 3.1 m (10 ft 0 in)
• Wing area: 26 m² (280 ft²)
• Empty weight: 860 kg (1,900 lb)
• Loaded weight: 1,260 kg (2,780 lb)
• Powerplant: 1 × Argon K-10 air-cooled inverted V8 engine, 180 kW (240 hp)

Performance

• Maximum speed: 175 km/h (109 mph) at 300 m (1,000 ft)
• Range: 380 km ()
• Service ceiling: 4,600 m (15,090 ft)
• Rate of climb: 4.8 m/s (945 ft/min)
• Wing loading: 48.5 kg/m² (9.9 lb/ft²)
• Power/mass: 143 W/kg (0.087 hp/lb)

Armament

• Guns: x2 Ksp-37 Machine Guns, with 250 rounds each
• Hardpoints: single or twin under-cabin hardpoints with a capacity of 100kg