A STEP PLATFORM

Field of the Invention

The present invention relates to a dual function aerodynamic cockpit step platform. It functions as a step by using the mount place of the cockpit step on the helicopter body and allows the possibility of the integration of payloads, which is mounted on the outside of the helicopter.

Background of the Invention

In today' s helicopters, there are too many electronic system devices mounted on so that there is no sufficient space to place the Payloads in the avionics compartment of the helicopters. All the helicopter flight equipment such as pilot interface units and avionics are located in the front section. For this reason, there should be rearrangement in the avionics compartment of helicopter in order to integrate new devices. Knowing the fact that helicopters have a specific weight/balance ratio and cable length limitations, some problems are encountered when new equipment is installed and rearrangement is necessary.

Because of the lack of space in the avionics compartment, the additional equipment is required to be placed on the outside of the helicopter body. In order to accomplish this task, an aerodynamic structure which protrudes out of the body of the helicopter must be built. This newly built space, which is protruding out of the body of the helicopter, must be structurally strong enough to withstand the flight conditions of the helicopter. Finite element method studies shows that the surface of the helicopter and the connecting members carrying the payloads are required to be strengthened so that it can withstand the flight conditions. To integrate this new structure, existing cockpit step had to be removed. Since a cockpit step is still necessary to enter and exit the cockpit of the helicopter and this function is built into the new structure. United States patent document US4333547, an application known in the state of the art, discloses a climb apparatus for vehicles. A ladder used in vehicles is comprised of flexible support members and steps. The support members have reinforcements to prevent bending in the opposite direction. United States Patent document no US2010122871 , an application known in the state of the art, discloses a tractor tire-mountable folding step ladder. A portable, foldable step ladder in a deployed configuration straddles a tire of a truck, tractor or other heavy vehicles, allowing an operator and mechanic to easily climb toward the engine compartment. This ladder has one step right above the tire and there are two lower steps connected to the first step with foldable structures.

Summary of the Invention

The objective of the present invention is to provide a step platform which enables the pilot and the passenger to enter and exit the cockpit of the helicopter. Also, it has to be structurally stiff and allow the integration of unit(s).

Another objective of the present invention is to provide a step platform which allows the payloads to be carried on the outer surface of the helicopter.

A further objective of the present invention is to provide a step platform which reduces aerodynamic performance losses by covering payload mounted outer surface of the helicopter. Detailed Description of the Invention

"A step platform" developed to fulfill the objective of the present invention is illustrated in the accompanying figures wherein,

Figure 1 is the perspective view of the step platform on the helicopter in the state of the art

Figure 2 is the perspective view of integrated new step platform structure. Figure 3 is the exploded view of the step platform inner section.

Figure 4 is the perspective view of the fairing used as cockpit step.

Figure 5 is the detailed perspective view of the step platform with fairing

Figure 6 is the perspective view of access cover and fairing.

Figure 7 is the frontal view of the access cover

Figure 8 is the perspective view of the inner section of fairing.

The components given in the figures are assigned with reference numbers as follows:

1. Step platform

2. Step compartment

21 . Step

22. Step upper frame

23. Step cover

24. Hinge

3. Main step frame

4. Step frame mounting structure

5. Payload plate

6. Mounting plate

7. Mounting bracket

8. Fairing

9. Access cover 91 . Air filter

92. Access cover air guide

93. Water retainer

94. Drain valve

10. External unit

1 1. External unit mounting plate

12. Outlet air guide

13. Light Source

14. Step frame mounting screw access cover

A. Avionics Compartment

H. Helicopter

F. Payload

The inventive step platform (1 ), which is designed to be used in the helicopters (H), enables the pilot and passenger to enter and exit the cockpit in an easy way and allows the payloads (F) to be carried safely, comprises,

at least one step compartment (2) which enables the pilot and/or passenger to enter and exit the cockpit of the helicopter (H),

at least one main step frame (3) on which the step compartment (2) is mounted,

at least one step frame mounting structure (4) which provides the connection of the main step frame (3) with the helicopter (H),

at least one payload plate (5) which is mounted on the main step frame (3) and on which the payloads (F) are carried,

at least one mounting plate (6) which is integrated on the other side of the payload plate (5)

at least one mounting bracket (7) which enables the mounting plate (6) to be fastened to the helicopter frame.,

at least one fairing (8) which covers the step compartment (2), payload plate (5) and mounting plate (6),

at least one access cover (9) in front of the fairing (8), at least one external unit (10) which is mounted on the surface of the fairing(8),

at least one external unit mounting plate (11) which enables the mounting of the external unit (10) on the fairing (8),

- at least one air exit guide (12) which is mounted on the payload plate (5) and enables the discharging of hot air released by the payload (F) to outside,

at least one light source (13) which enables the helicopter to be detected in night flights,

- at least one step frame mounting screw access cover (14) which enables to access to mounting screws used for mounting the main step frame (3) to the step frame mounting structure (4).

The subject of the invention is a step platform (1 ) which is designed to be used in the helicopters (H), enables the pilot and passenger to enter and exit the cockpit easily and allows the payloads (F) to be carried safely thanks to fairing (8).

The step compartment (2) comprises,

- at least one step (21) which enables the pilot and passenger to enter and exit the cockpit of the helicopter (H) easily,

at least one step upper frame (22) which is mounted on the step (21), at least one step cover (23) which enables the step (21) to remain closed when it is not in use

at least one hinge (24) which enables the step cover (23) to be mounted on the step upper frame (22).

The access cover (9) comprises

at least one air filter (91) which enables the inlet air to be filtered from the solids larger than its mesh size,

at least one access cover air guide (92) which enables the incoming air to be routed, at least one water retainer (93) which enables the incoming air to flow through payload (F) air inlet and disables the water to access the payloads (F) ,

at least one drain valve (94) which enables the water accumulated in the water retainer (93) to be discharged.

In order to avoid structural limitations encountered in arrangements of payloads (F) performed in avionics compartments (A) of the helicopter used in the previous art, the step platform (1) enabling the pilots to enter and exit the cockpit of the helicopter (H), structurally strong and enabling the desired payloads (F) to remain securely thereon enables to minimize the aircraft performance losses originating from the step platform (1) considering the aerodynamic factors. In the step compartment (2), the step upper frame (22) is mounted on the step (21). The step cover (23) designed to protect the step (21) from the environmental effects is mounted on the step upper frame (22) via the hinge (24) and it preferably rotates through the step compartment (2). Therefore, the pilot or the passenger uses the step (21) by pushing the step cover (23) with his foot through the step compartment (2). The step compartment (2), as a whole, is mounted on the main step frame (3) which is located at the back (on the body part of the helicopter (H)). The main step frame (3) is mounted to the helicopter (H) from its one end via the step frame mounting structure (4). The payload plate (5) is mounted on the surface of the main step frame (3) facing the helicopter body (H). Mounting plate (6) and connection brackets (7) are used to mount the payload plate (5) to the frames of helicopter (H).

The fairing (8) has access cover (9) which allows to access the payload (F) without needing to dismount the fairing (8) when any intervention is required. Therefore, the access cover (9) is preferably located in front the fairing (8). Another aim is to control the air which flows into the fairing (8). Thanks to the air filter (91) located on the outer surface of the access cover (9), the air which flows through the fairing (8) is filtered and then flows through payload (P). The air inlet is required in order to supply the thermal conditions required for the operation of payloads (F). On the inner surface of the access cover (9), there is an access cover air guide (92) which routes the air coming from the air filter (91). Furthermore, in order to prevent the possible damages of water coming in from the outside (especially on rainy days) to the payload (F), there is a water retainer (93) located on the inner surface of the access cover (9). For the discharge of the water accumulated in the water retainer (93), there are drain valves (94) on the outer surface of the access cover (9). The accumulated water is discharged through the outer surface of the access cover (9) without reaching inside the fairing (8) by means of the drain valves (94). In the preferred assembly sequence of the invention, firstly, the step compartment

(2) is mounted. Then, it is mounted on main step frame (3). The main step frame

(3) is mounted to the step frame mounting structure (4) by a screw from its one edge, thus the first connection with the helicopter (H) is provided. The payload plate (5) is mounted to the side of the main step frame (3) on which the step compartment (2) is not located such that it will preferably be vertical to the main step frame (3). The mounting plate (6) is mounted on the other edge of the payload plate (5) not connected to the main step frame (3), and the connection brackets (7) are mounted on the mounting plate (6). The connection brackets (7) are mounted on curved frames of the helicopter (H) by means of their special structure. Therefore, the group comprised of the step compartment (2), main step frame (3), payload plate (5) and the mounting plate (6) which are connected to each other is attached to the helicopter (H) from both sides. The heat generated during the operation of the payload (F) is discharged through the outlet air guide (12) that is connected to the payload plate (5) from its one edge. Finally, the fairing (8) is mounted in order to cover the step frame mounting structure (4), payload (F), payload plate (5), mounting plate (6), and the connection brackets (7). In the preferred embodiment of the invention, in order to increase the stiffness and the step area on the fairing (8), the fairing (8) is preferably mounted on the helicopter body (H) with L shaped brackets.

The external unit mounting plate (1 1) which is preferably located on the outer surface of the fairing (8) and enables the external units (10) to be placed inside the fairing (8) enables the external unit (10) to be mounted on the helicopter (H).

The air flowing through the fairing (8) is routed in the entrance part by the access cover air guide (92) on the inner surface of the access cover (9), and the hot air coming out of the payload (F) unit inside the fairing (8) is discharged by the outlet air guide (12).

In the preferred embodiment of the invention, the load carrying parts such as step compartment (2), main step frame (3), step frame mounting structure (4), payload plate (5), mounting plate (6) and the connection brackets (7) are preferably manufactured from heat treated aluminum material, and the parts which doesn't carry loads and have complicated shapes such as fairing (8) and access cover (9) are preferably manufactured from composite material in order to decrease the weight of the step platform (1).

The inventive step platform (1) eliminates the structural limitations encountered in the payload (F) arrangements made in avionics compartment (A) of the helicopter (H) by means of the fairing (8) structure. By means of the step platform (1) designed by considering the aerodynamic factors, the performance losses are minimized. Besides, the step platform (1) is applied on both side of helicopter (H), symmetrically. In the preferred embodiment of the invention, there are step frame mounting screw access covers (14) which enable the access to step frame mounting screw in case of maintenance of the screw without demounting the fairing (8).