Abstract:
A dynamic parachute four-line release simulator device which allows  aircren to practice the steps necessary to assure a safe parachute descent and landing following emergency aircraft egress. The device is suspended at a desired height adjacent a raised platform, and is constructed of a cross-braced metal ring having parachute suspension lines connected thereto via bungee cords and eye bolts; a parachute riser assembly, which serves as an attachment point for aircrewmen trainees, is connected to the suspension lines via metal connector links.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to training devices for parachutes and particularly to a simulator for parachutes using a four-line release system. 
     A four-line release modification has been incorporated into certain standard flat parachutes to give aircrewmen steering capabilities, to impart a forward velocity of 4-6 knots, to lower the parachute descent rate, and to minimize the possibility of parachute/man entanglement upon water entry. 
     There are no effective training aids presently available to simulate post egress (under parachute) conditions to give aircrewmen an opportunity to practice and rehearse parachute descent survival techniques in a realistic hands-on environment using a four-line release system. 
     The dynamic parachute four-line release simulator of this invention is operable for indoctrinating aircrew personnel on the proper use of parachute four-line release, and serves as a post egress trainer, permitting aircrew personnel to learn and practice proper procedures in preparation for parachute landing. 
     SUMMARY OF THE INVENTION 
     The present simulator device is constructed from a cross-braced metal ring suspended a suitable distance above and adjacent to a raised platform, using a support brace or other suitable support. Parachute suspension lines are attached to the metal ring, and a parachute riser assembly is connected to the suspension lines and serves as an attachment point for the parachute harness of an aircrewman trainee on the platform. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a preferred embodiment of a simulator device of the present invention. 
     FIG. 2 is a top view of the simulator device support ring. 
     FIG. 3 is a front elevational view of the simulator device. 
     FIG. 4 is a side elevational view of an embodiment of the simulator device. 
     FIG. 5 shows a detailed illustration of a bungee cord used in the simulator device. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The dynamic parachute four-line release simulator as shown in the drawings, includes a sturdy metal ring 10, of steel for example, with a plurality of cross members 12 welded to the ring and at the center to a circular plate 14. A plurality (e.g., twenty-eight) of eye hook bolts 16 are equally spaced about the circumference of ring 10 and fastened to the underneath side by welding or other suitable means. Eye hooks 16 each support an elastic bungee cord 20 which in turn provide &#34;under parachute canopy&#34; simulation. 
     Bungee cords 20 each consist of a length of elastic cord 21 (approximately 18 inches in length) having loops 24 and 25 formed at opposite ends thereof fastened with hog rings 27 and 28, respectively. Loops 24 and 25 are protected against wear by anti-chafing pads 29 provided within each loop. 
     Parachute suspension lines 30 are attached to respective loops 25 at the lower end of each bungee cord 20 with a loop 31, as shown. The parachute suspension lines 30 run down to four parachute connector links 33, 34, 35 and 36. Respective suspension lines 30 (i.e., approximately seven) attached to each quadrant of the ring 10 have their lower ends attached to connector links 33, 34, 35 or 36, respectively, as shown in the drawings. Connector links 33 and 34, at the front, are joined together side by side with a parachute cross-connector strap 37, and connector links 35 and 36, at the rear, are joined together in a similar fashion with a parachute cross-connector strap 38 as shown. Connector links 33, 34, 35 and 36 also hold the nylon parachute riser assembly 40, comprising webbing 41, 42, 43 and 44. At the distal ends of riser assembly 40 are two quick-release parachute (KOCH) fittings 46 and 47. 
     Lanyards 48 and 49 are arranged (e.g., daisy chained) for operation to release two parachute suspension lines 30a from each of the rear riser connector links 35 and 36, respectively, when an aircrewman initially pulls down on the lanyard cord. In a normal situation using an actual parachute, by freeing these two suspension lines on each side (i.e., a total of four suspension lines), the aircrewman would be controlling his descent by allowing additional air flow from under the rear side of the parachute canopy giving him directional control (i.e., forward movement) and also reducing any oscillation. 
     The simulator assembly is suspended from a support brace (not shown) by means of a cable 51 attached to eye bolt 53 affixed to the top of circular plate 14. Two steering lines, 55 and 56, are attached to a fixed point (not shown). The ends of lanyards 48 and 49 are normally connected to a respective unreleased line 30 at 57 as shown in FIG. 4. This provides a control, for an actual parachute in descent, to pull on either side of the parachute canopy controlling air flow direction at the rear of the canopy whereby the parachute can be directed to turn to the left or to the right. On the training simulator device, however, the top end of the lanyards 48 and 49 are connected via respective pulley means 58, on either side to respective steering lines 55 and 56 (see FIG. 1) which in turn operate to cause the ring 10, etc., to rotate to the left or to the right, depending upon the lanyard operated, thus simulating the rotation that would result with an actual parachute in descent. These features on the simulator allow aircrewmen trainees to simulate control of an actual four-line release parachute. 
     The dynamic simulator assembly is positioned high enough to support an aircrewman at least two feet or more above the ground while being suspended therefrom. Any suitable platform can be used to assist a trainee reach the quick release parachute fittings 46 and 47 on the dynamic simulator assembly. 
     When using the device, an aircrewman trainee wearing all of his personal survival equipment, steps onto a platform (not shown) and connects his parachute harness to the parachute release fittings 46 and 47 of the dynamic simulator device. The platform is then removed leaving the aircrewman, with his survival kit, suspended from the simulator device. He can then go through the post egress emergency procedures to prepare for parachute landing over water or land including operating the parachute four-line release system for controlling direction of descent, etc. 
     To receive a similar degree of realistic survival training, an aircrewman would be required to make an actual parachute jump, use the parachute four-line release modification and practice other procedures during descent. This, of course, would be dangerous and very costly. The disclosed simulator uses no energy to operate, requires no aircraft, and is free of any of the hazards associated with an actual parachute jump. The material to construct the simulator can be of several varieties. The ring 10, cross members 12, and plate 14, can be made from any type steel or aluminum, for example, and the eye hooks 16 can be either welded or bolted to the ring. The anti-chafing pads on the elastic bungee cords 20 can be made of leather, canvas, cotton, naugahyde, vinyl, or equivalent fabrics. Any type of elastic bungee cord which produces the springing action characteristics of the &#34;under parachute canopy&#34; condition is acceptable. The parachute suspension lines can be made from any suitable material. The parachute connector links, cross connector straps, riser assemblies and canopy connectors are readily available. Even overage, surveyed, parachute assemblies that are readily available and usable and can be used to construct this dynamic parachute four-line release simulator. 
     Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.