Patent Publication Number: US-2015069185-A1

Title: Cushioned Platform System for Aerial Delivery

Description:
BACKGROUND 
     This disclosure relates generally to devices and techniques for reducing shock loading from landing aerial platforms. More particularly, this disclosure relates to devices and techniques for reducing shock loading to payloads mounted on platforms and dropped from military aircraft. 
     Type V platforms are typically used for aerial delivery of payloads ejected from military cargo aircraft. Such platforms descend by parachute and typically have no intrinsic energy absorption mechanism to reduce landing deceleration. One conventional technique is to add energy dissipating material (EDM) between the payload and the platform to reduce the shock. The deficiency of EDM usage is that it is inconvenient to rig and de-rig. In addition, the resulting shock levels (even when EDM is used) are excessive for some payloads. 
     The existing systems which employ airbags to reduce shock are not compatible with most military cargo handling and parachute deployment systems. Conventional proposals, which employ pressurized under-platform airbags, are unduly complex, have high maintenance costs and present extra hazards within the aircraft. Proposals, which use pressurized airbags above the platform, do not appear to have any significant advantage over EDM despite the introduction of certain additional hazards. Other proposed systems for reducing load shock employ airbags mounted under type V platforms in combination with hinged trap doors. Either the design has insufficient roller contact for efficient loading, or the design does not have a safe locking and opening system. 
     A number of proposals inject a vertical acceleration to the platform just before impact. Such systems are relatively complex, have not established a high degree of effectiveness, add considerable weight and significantly reduce reliability. 
     SUMMARY 
     Briefly stated, a cushioned aerial platform comprises a platform assembly having an upper platform for receiving cargo and a lower portion. A pair of parallel outer rails is mounted for partial disposition at the lower portion. A pod of airbag modules is disposed below the lower portion between the outer rails. The airbag modules are configurable in a non-deployed mode and a deployed mode. A pair of parallel inner rails is mounted to the airbag modules and positionable to secure the modules in the non-deployed mode. Securement members on the outer rails are engageable to selectively lock the platform in the cargo hold of an aircraft. A release mechanism is automatically actuatable to permit the airbag modules to deploy. The inner rails drop to transform the airbag modules to a deployed mode upon actuating the release mechanism. 
     Each airbag module further comprises a lower panel which mounts the inner rails and drops to force the airbag module to deploy upon actuating the release mechanism. Each airbag module comprises a plurality of outlet vents. The outer rails and the inner rails comprise roller pads which are generally co-planar in the non-deployed mode. The automatic release mechanism is preferably a variant of the operating lever of an extraction force transfer coupling (EFTC). 
     The airbag modules preferably comprise fabric sidewalls and connector members connect between the sidewalls. An extraction parachute is operatively connected to the platform assembly. The airbag modules include airbag vents which provide a partially deflated configuration upon landing. The airbag modules are reconfigurable in the non-deployed mode after assuming the deployed mode. 
     A cushioned aerial platform comprises a platform assembly having an upper platform for receiving cargo and an underside. A pair of parallel outer rails is mounted for at least partial disposition at the underside. At least one airbag module is disposed below the underside between the outer rails and is configurable in a non-deployed mode and a deployed mode. A pair of parallel inner rails is mounted to at least one said airbag module and is positionable to secure the at least one module in the non-deployed mode. Flange members are engageable to selectively secure the platform in an aircraft. A release mechanism is actuatable to permit said at least one airbag module to deploy. The inner rails drop relative to the platform underside to force the at least one airbag module to deploy upon actuating the release mechanism. 
     Each airbag module further comprises a lower panel which mounts the inner rails and drops to force the airbag module to a deployed mode upon actuating the release mechanism. Each airbag module includes a plurality of outlet vents. The inner and outer rails comprise elongated roller pads which extend from one end to an opposite end of the platform assembly. An extraction parachute is operatively connected to the platform assembly. 
     An aerial delivery method comprises loading a payload on a platform and rolling the platform into an aircraft cargo hold. The method further includes locking the platform into a stable position within the aircraft. The method also further comprises extracting the payload and the platform from the aircraft via an extraction parachute and deploy a main parachute suspending the payload and platform for descent. The method also includes automatically deploying at least one airbag module below the platform with the aid of the inner roller pads dropping prior to the landing of the payload and platform. 
     At least airbag module is repacked in a non-deployed mode after landing of the payload and platform. The platform is at least partially unlatched from the aircraft prior to extracting the payload and the platform. The step of deploying further comprises automatically actuating a mechanical release mechanism. 
     A retainer is released for said at least one airbag module to allow the airbag module to drop downwardly relative to the platform under the force of gravity. The step of deploying the airbag module further comprises actuating an operating lever similar to the operating lever of an EFTC. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a generally top perspective view of a cushioned platform as configured in an aircraft; 
         FIG. 2  is a bottom perspective view of the cushioned platform; 
         FIG. 3  is an end elevational view of the cushioned platform of  FIG. 1 ; 
         FIG. 4  is an upper perspective view of the cushioned platform of  FIG. 1  in a fully deployed configuration; 
         FIG. 5  is a bottom perspective view of the cushioned platform in the deployed configuration of  FIG. 4 ; 
         FIG. 6  is an end elevational view of the cushioned platform in the fully deployed configuration of  FIG. 4 ; 
         FIG. 7  is an upper perspective view of the cushioned platform of  FIG. 1  in a partially compressed configuration; 
         FIG. 8  is a bottom perspective view of the cushioned platform in the partially compressed configuration of  FIG. 7 ; 
         FIG. 9  is an end elevational view of the cushioned platform in the partially compressed configuration of  FIG. 7 ; 
         FIGS. 10A-10C  are top perspective views of a representative airbag module in a packed mode, a fully expanded mode and a mode under compression for the cushioned platform in the configuration of  FIGS. 1 ,  4  and  7 , respectively; 
         FIG. 11  is an enlarged fragmentary end perspective view, illustrating a representative lock/release assembly for the airbag modules employed in the cushioned platform; 
         FIG. 12  is an enlarged fragmentary end perspective view, further illustrating the lock/release assembly of  FIG. 11 ; 
         FIG. 13  is an enlarged fragmentary top plan view of the decking system and lock/release assembly of  FIG. 11  employed in the cushioned platform; 
         FIG. 14  is an enlarged fragmentary top perspective view of the decking system and lock/release assembly for the cushioned platform of  FIG. 11 ; 
         FIG. 15  is an elevational view, portions removed and partly in schematic, of a military transport aircraft with a cushioned platform and a representative payload in the form of a vehicle ready for an aerial delivery as viewed from the aft of the aircraft; 
         FIG. 16  is an enlarged perspective view, partly in diagram form, illustrating the vehicle secured to the top of a cushioned platform and illustrating an extraction line; 
         FIG. 17  is an enlarged perspective view, partly in diagram form, of a cushioned platform together with a secured vehicle further illustrating a deployment line and suspension slings for a main suspension parachute; 
         FIG. 18  is an enlarged perspective view, partly in diagram form, from the aft thereof further illustrating the cushioned platform and the vehicle, an extraction line, a deployment line and slings for the platform and vehicle; 
         FIG. 19  is an enlarged perspective view, partly in diagram form, of the cushioned platform and the vehicle further illustrating the extraction and the deployment lines in diagram form; 
         FIG. 20  is an enlarged perspective view, partly in diagram form, illustrating the cushioned platform and secured vehicle together with an extraction line and suspension lines; 
         FIG. 21  is a perspective view of the cushioned platform and secured vehicle, partly in schematic and diagram form, and partly illustrating the deployment line for deploying the suspension parachute; and 
         FIG. 22  is a perspective view illustrating the cushioned platform and secured vehicle during descent together with the suspension lines for the suspension parachute; 
     
    
    
     DETAILED DESCRIPTION 
     With reference to the drawings wherein like numerals represent like parts throughout the several figures, a cushioned platform is generally designated by the numeral  10 . With reference to  FIGS. 15 and 16 , the cushioned platform is particularly adapted for aerial delivery of secured cargo or a payload via a military aircraft  12 . A representative payload  14 , such as a vehicle, is rolled, driven or otherwise placed onto the platform in a conventional manner and retained in place by conventional securement techniques, such as tie-down chains or securement cables  16 . The entire payload plus the platform is then loaded onto the aircraft, rolled over rollers into the cargo hold  18  and locked into a stable position with the aircraft cargo handling system in the cargo hold  18 . 
     The airborne aircraft  12  with the cushioned platform and payload approaches the delivery zone. The cushioned platform  10  with the payload  14  is then extracted from the aircraft by an extraction parachute  130  and delivered by a main suspension parachute  140 . An integrated cushioned system, as described below, which features airbags is automatically deployed during descent to cushion the landing of the loaded platform. The cushioned platform  10  with the airbag cushioned system is reusable for subsequent aerial delivery. 
     The platform  10  comprises an upper receiving surface or deck  20  of conventional form and function which longitudinally extends between ends  22  and  24 . A starboard extruded rail  30  extends the longitudinal length of the platform and a transversely opposite port extruded rail  40  also extends the longitudinal length of the platform. The starboard and port rails  30  and  40 , respectively, include a lower elongated roller pad  32  and  42 . The starboard rail includes upwardly protruding flanges  34  and  36  with cutouts which interface with the cargo handling system. Likewise, the port rail has upwardly protruding flanges  44  and  46  which interface with the aircraft cargo handling system. The flanges  34 ,  36 ,  44  and  46  lock the platform upwards, outwards, fore and aft in a stable position in the cargo hold  18  of the aircraft. 
     A pod  48  of substantially identical airbag modules  50  in compact non-deployed packed form are mounted in a linear arrangement at the underside of the platform between the outboard and inboard rails  30  and  40 . The airbag module  50  may assume several forms and include one or more airbags. Each airbag module  50  is representative of various possible embodiments. 
     With additional reference to  FIGS. 10A-10C , each airbag module  50  employs a top panel  52  which is connected by a bottom panel  54  and an intermediate circumferential sidewall  56  of fabric material. The panels  52  and  54  may have flange-like frames  53  and  55 , respectively. In one embodiment, internal catenaries (not illustrated) and cables (not illustrated) may be employed to connect to distribute the load and shape the circumferential sidewall so that the sidewall inflates substantially uniformly. A support skeleton  58  (visible through access openings in panel  52  of  FIGS. 10A and 10C ) is preferably disposed within the airbag module. The function of the support skeleton  58  is to provide a load path between the payload and the central roller trays in the aircraft. This maximizes load carrying capability of the platform by distributing load to all four aircraft roller trays. Aircraft roller load limit is one of the restrictions on platform payload capacity. The skeleton  58  is attached to the lower panel  54  only, permitting both a single airbag module across the width of the platform yet maintain a load path to all four roller trays when the platform is in the aircraft. The inflatable element includes outlet vents  57 . In one embodiment, there are 36 outlet vents  57 , although the number and dimensioning of the vents may vary. The bottom panel includes inlet vents  59  which may also provide access to the interior of the airbag module for inflation. 
     Each airbag module  50  has a packed, non-deployed configuration of  FIG. 10A  which is ultimately deployed to an expanded, fully inflated configuration of  FIG. 10B  and, upon landing or deceleration, the partially compressed configuration  FIG. 10C . The outlet vents  57  are dimensioned and configured to selectively control the compressed configuration. In one embodiment, each module has a length of approximately four feet and upon expansion, extends approximately thirty-six inches in height. 
     Spaced transversely extending supports  60  optionally mount over the interface of adjacent airbag modules  50  at the underside of the platform. The supports and/or bottom panels  54  mount a pair of parallel spaced, elongated roller pads  62  and  72 . In one embodiment, the supports  60  or roller pads  62  and  72  are internally supported by the support skeleton  58  within the airbag module. Roller pads  62  and  72  are parallel to the roller pads  32  and  42  and, in the aircraft configuration of  FIG. 2 , are generally coplanar therewith. It will be appreciated that in the aircraft configuration, the platform is compatible for rolling on the conventional four rolls of rollers typically provided in the aircraft cargo hold  18 . The support skeleton  58  supports the roller pads  62  and  72 . Locks  74  secure the upper panel  52  to the platform deck  20 . 
     With reference to  FIGS. 1 and 3 , an operating lever  80  similar to the operating lever of an EFTC is mounted to the rail  30 . The operating lever  80  connects with a cord or cable for deploying the airbag modules  50  as described below. 
     The airbag modules  50  may be retained to the underside of the platform by various means and are preferably released concurrently for deployment. In one embodiment, a spring-loaded flange-like lever lock/release assembly  90  retains the pod of airbag modules  50  in a non-deployed state at the underside of the platform. For some embodiments, multiple retention lock/release assemblies (not illustrated) are employed. A pin  92  at the port and starboard may extend through a portion of a spring shaft  96  and connect via ripcords  98  to a pulley  100 . The pulley is rotated by actuation of the operating lever  80  on a cable  82  and a mirror EFTC-like operating lever  84  connected to the pulley  100 . All of the lever/lock releases  90  are thereby concurrently released. The operating lever functions as a sprung lever once the platform is out of the aircraft. The pulley/cable assemblies are housed in an elongated nose-piece  110  at the end of the platform. An actuating rod  120  connects all the lever locks  122  on each side of the platform. The lever locks pivot to release the flange  55  on the airbag module. 
     Ultimately in another embodiment, releasable locks are only provided on one side of the assembly. Other means for releasing the bottom panel to allow it to descend are also possible. 
     When the EFTC-like operating lever  80  is released, each lock/release assembly  90  is released. In addition, the mass of the supports  60  and the mounted roller pads  62  and  72  pull or otherwise force the airbags  50  downward by gravity. The airbags inflate during descent. 
     The cushioned platform  10  in the configuration of  FIGS. 1-3  receives the payload and the cushioned platform  10  is rolled over the rollers (not illustrated) on the four roller pads  32 ,  42 ,  62  and  72  to the proper position within the aircraft hold. The platform is locked into place in the hold  18  by the flanges  34 ,  36 ,  44  and  46 . The outer and the inner roller pads  32 ,  42 ,  62  and  72  slidably engage the four parallel lines of rollers in the aircraft. 
     With additional reference to  FIGS. 15-22 , during the aerial delivery, the forward aft latches on the port side are disengaged. The extractor parachute  130  is activated. The force generated by the extractor parachute via the extraction line  132  ( FIG. 17 ) overcomes the preload of the fore and aft latches on the starboard side of the aircraft. The cushioned platform  10  is then pulled out of the aircraft. An EFTC actuating cable  134  ( FIG. 16 ) activates an EFTC latch  136  to disconnect the extractor parachute  130  from the platform. 
     Upon extraction, an EFTC coupling (not illustrated) releases a deployment line  138  and initiates the transition from the extractor parachute to the main suspension parachute  140 . The deployment line  138  tenses and triggers the opening sequence of the main parachute  140 . The parachute bag is pulled off of the main parachute  140 . Four suspension slings  144  are attached to tandem fore and aft links  146  on the platform  10 . The suspension slings  144  tense as the parachute deploys. 
     As the cushioned platform  10  descends, once the platform sufficiently slows, the airbag modules  50  are then deployed. The deployment is accomplished by a mechanical release of the bottom structure of the airbag modules  50 . Preferably, the mechanical release is initiated by the operating lever  80  and a mirror operating lever  84  with a delay. Alternatively, a lazy leg with delay from the main parachute cluster may also be employed. The airbag modules  50  essentially deploy by gravity. The mass of the center roller pads  62  and  72  and the supports  60  pull or force open the airbag modules  50  for inflation of the sidewalls. During descent, air fills and inflates the airbags. 
     Upon landing, the inlet vents seal  59  and the airbag modules pressurize. Outlet vents  57  are dimensioned to provide a reaction force to progressively slow the platform. Upon landing, the payload is released by disconnecting the various securement hardware including cables  16 . The complete cushioned platform can then be retrieved and repacked to the non-deployed configuration of  FIG. 2 . 
     Various adjustments can be implemented for the cushioned platform. For example, one or more airbags may be eliminated. In addition, the throttle on the outlet vents  57  may be modified to provide the proper cushioning for a given payload. 
     It will be appreciated that the cushioned platform  10  provides a very efficient storage of the airbags and a very efficient deployment when needed. The continuous roller pads  62  and  72  are employed to link the separate airbag modules together to ensure that they open together. In addition, the roller pads add mass to facilitate deployment of the airbag modules. The roller pads  62  and  72  also provide a continuous surface upon installation or extraction to prevent jamming between the separate airbag modules. The roller pads  62  and  72  also function to facilitate loading the platform  10  in the cargo hold  18  by providing a rolling surface for the rollers. Of course, the airbag system can be configured to adjust the venting to accommodate a reduced and a concentrated payload. 
     While preferred embodiments of the foregoing cushioned platform assembly have been set forth for purposes of description, the foregoing should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations and alternatives may occur to one skilled in the art without departing from the spirit and the scope of the present invention.