Longer than other Storm’ models (12 inches more than 300), the fuselage of Storm 500 consists of two basic sections: the first section includes landing gear beam, wing beam and cabin section, and the sheet-metal tail cone section. The landing gear bolts on to the assembled fuselage section. The all sheet metal fuselage is a conventional semi-monocoque structure: a basic rectangular section formed by four longerons, with skins blind riveted to the longerons (and stiffeners). Two rounded bulkheads form the top skin. The cabin area of the fuselage is unique in many ways. It was designed for today’s pilots who are significantly taller than pilots were 50 years ago. A typical six-foot six-inch pilot will sit comfortably with plenty of head room to spare even while wearing headsets. Visibility is excellent through windows. The front seats are positioned near the front of the wing so that the downward visibility to the ground is excellent. 

The cabin width is an amazing 43 inches from window to window and higher 2 inches than other Storms, making it the widest cabin in its class. The adjustable back seats support fold forward to allow access to the rear seats. Two inspection holes are located under the seats for easy access to the spar for wing removal. The aircraft seats are very comfortable even after a 5 hour trip thanks to the special foam that adjusts its shape. The seat belts are easy to adjust and require no maintenance. The Storm 500 wing design has a thicker wing section than other Storm models. A thick cantilever wing provides maximum strength at minimum weight. It is also aerodynamically efficient since there is no drag-inducing exterior bracing. The wing has a high lift airfoil and wing tips to maximize the Storm 500 effective wing span.

The wing is of all-metal stressed-skin full-cantilever low-wing design consisting of two wing panels bolted to a spar box assembly in the fuselage. The cantilever wings are attached to each side of the fuselage by insertion of the butt ends of the main spars into a centre spar structure which is an integral part of the fuselage. The rear wing attachments introduce the wing torsion and shear into the fuselage. The main spar structure provides in effect a continuous main spar with splices at each side of the fuselage. Thanks to the high strength of this spar, a relatively low number of wing ribs and stiffeners is needed, thus simplifying construction. The efficient use of parts in the design limits the number of parts required, reducing assembly and maintenance times. The wings are not tapered and have no "twist," making them easy to build and maintain. Two separate spars make up each wing with the main spar being in 25% from wing leading edge.

The two spars are fastened to the fuselage by means of AN bolts, making the wings easy to remove. The main spar is made up of eleven 2024T3 plates solid riveted to a web, similar to an "I" beam. At the wing tip, the Storm 500 design utilizes tips to maximize the wing’s effective lift area and to minimize wing tips vortices. Storm wing tips provide the largest effective span for a given geometric span or a given wing weight. The ailerons and flaps make up the wing controls. The ailerons are made of formed aluminium skins held in place with ribs. They are light, easy to install, and have counter balance weights. They are connected to push/pull rods which are connected to a simple bellcrank in the wing. Control cables are connected between the bellcrank and the fuselage torque tube, which is connected to the yokes. The empennage (tail) of the new Strom 500 demonstrates the design and construction efficiency of S.G.Aviation. The tail is comprised of a single horizontal tail (stabilator) and a single vertical tail (rudder).

The stabilator is dynamically balanced and mounted to the fuselage with two large steel bearings. Operation of the stabilator is through the push-pull movement of the control wheel yoke control. The "flying tail" stabilator is equipped with dual trim tabs (interconnected) mounted on the trailing edge. The trim tab is actuated by an electric trim motor, which is activated by the pilot by moving a electric trim wheel, similar to conventional aircraft. The stabilator construction is a conventional semi-monocoque structure. Individual aluminium ribs riveted to a large box type spar enclosed in aluminium skins make up the stabilator. The one piece control surface does not have any moving parts other than the dual trim tabs which are piano hinged at the trailing edge. The stabilator control cables are adjustable through the large access panel under the rear fuselage bottom. Like all Storm models, the Storm 500 features an all-flying vertical tail (rudder) section for excellent effectiveness and control, especially at low speeds.

The all-flying rudder provides responsive rudder control, while also minimizing weight and complexity (there’s only one vertical tail section). Two rudder bearings bolt to the rear fuselage to fix the rudder to the fuselage. The rudder is dynamically balanced by a small weight installed in the leading edge. Operation of the rudder is through the movement of the rudder pedals. The rudder is "self centring" in flight through the nose wheel strut bearing. Construction of the rudder is a conventional semi-monocoque structure. Individual aluminium ribs riveted to a simple "U" channel spar enclosed in aluminium skins make up the rudder. The one piece rudder control cables are connected with turnbuckles to the rudder which can be adjusted from the outside of the aircraft. The "self centring" and easy to adjust cables eliminate the need for a fixed rudder trim tab. The heavy-duty tricycle gear system was chosen as the standard gear configuration for the Storm 500 to meet the needs of today’s pilots: Most pilots are not experienced ‘taildragger’ pilots, and a tricycle gear provides better stability and control on the ground.

Borrowed from the Storm 300, the Storm 500 utilizes a heavy duty gear system developed specifically for flight training operations. The main gear is a 2 aluminium springs that provide double cantilever deflection. Four large bolts for each side hold up the 2 springs to a fuselage beam inside.

It provides excellent grass-field capability, and is very durable, simple and virtually maintenance-free. The nosewheel strut uses a single heavy-duty bungee for shock absorbency. The nosewheel is steering, with direct linkage to the rudder pedals for very effective and responsive ground handling and tight turns. The main wheels are equipped with hydraulic disk brakes.

The Storm 500’s gear has been developed to allow grass-field operation, and the direct linkage steering nosewheel, provide remarkably precise ground handling and steering.

The brakes are actuated by toe brake pedals which are attached to the rudder pedals. The master cylinders with reservoirs are connected to the pedals on the pilot side, and standard master cylinders are on the passenger side. No additional brake fluid reservoir is used. Brake lines are made of clear heavy duty nylon tubing. This makes it easy to bleed the brakes and very easy to install and remove the lines.

The nose gear is steering through a 22° degree arc each side of centre by the use of the rudder pedals. Steel 3/8 inch diameter rods connect the rudder pedals to the nose wheel. This gives the aircraft accurate and tight steering. The nose wheel design is unique in that it is very simple. The nose wheel strut is held in place with two large nylon bearings, impregnated with oil. The lower bearing is machined so that the strut "self centres" which also centres the rudder. The nose wheel is attached to a ¾ inch thick aluminium wheel fork which is bolted to the nose strut. The nose strut is 2 inch diameter 4130N steel tubing. The result is an all around extra tough nose gear assembly which has no O rings, back-up rings or gaskets. Additionally, no shimming is required.