CA2444308A1 - Vertical escape system with reduced sail area for aircraft - Google Patents

Abstract

An escape system for use in aircraft includes a support frame for deployment adjacent an aircraft hatch, and a vertical fabric chute to receive passengers from the aircraft and lower them at a controlled speed to ground level. The support frame includes an entranceway which may include a drape to alleviate passenger fears.
The effective sail are of the vertical chute may be minimized to prevent movement in windy deployments, either by bunching the chute with breakaway bands which burst when the first passenger descends and/or cutaway portions in the fabric backing panels. The system includes a landing platform, which may be arranged for deployment in either a horizontal or angled position, and a life raft joined to the landing platform.

Description

TITLE OF THE INVENTION
VERTICAL ESCAPE SYSTEM WITH RE~UCE~ SAIL AREA FOR AIRCRAFT
FIEL~ OF THE INVEhITION
The invention relates to escape devices for aircraft, to permit passengers and personnel to escape from an aircraft in the event of an emergency.
BACKGROUND OF THE INVENTION
Traditional escape devices for aircraft consist of an inflatable slide, which deploys from an aircraft hatch. More recently, it has been proposed by the present inventor to provide a vertical marine-type fabric escape chute which can deploy from an aircraft hatch in an emergency situation. Typically, a rigid frame is provided which extends outwardly from the hatch upon deployment, with a vertical chute descending from the frame. The frame may be unfolded or otherwise opened such that it maintains its rigidity and ability to support. a load even when supporting a dumber of simultaneously descending passengers. The frame would normally include bracing struts which contact the aircraft fusilage. A slide or raft may be provided at the base of the chute to safely receive descending passengers. The chute is a generally conventional marine-type chute consisting of a fabric tube with internal baffles for slowing the rate of descent of passengers. As well, the baffles prevent users from viewing the full ledgth of thE: tube, thus minimizing the "fear factor" which might otherwise be involved in descending such a chute.
Several demands are placed on aircraft Eacape devices. They must be capable of use in both marine and dry-land deployment, with minimal injury to passengers. They must be capable of rapid use by passengers. As well, they must be capable of safe deployment in windy conditions without blowing about. For the first requirement, the system must safely deposit passengers onto a hard surface such as a tarmac at the base of the aircraft. As wE:ll, the system must include a life raft or other means to provide flotation to passengers. As to the second requirement, a factor which tends to slow the deployment of passengers is the fear of heights which acts on passengers exiting an airplane hatch when they plainly see the drop to be descended without visible protection. Passengers may "freeze"
and thus slow up the escape process. As to the third requirement, a system should be capable of remaining reasonably stable in a windy deployment, thus presenting a minimal "sail" area in relation to its weight. Vertical marine-type escape chutes, especially those using a backing panel, tend to present a reasonably large sail area in relation to their relatively light weight at the time prior to their use.
When in use, the problem is greatly reduced as the weight of the descending passengers stabilizes the system. Hence, it is desirable to provide a system in which the sail area is effectively reduced, at least prior to the descent of the first user, The present invention relates to improvements in the design of vertical escape chutes.
SUMM~4R~' OF THE INVENTION
The VES or vertical escape system of the present invention is comprised of four primary components: the Entranceway, the DIED (vertical descent device, or chute), the Landing Platform and the Life Raft.
The Entranceway. The Entranceway of the VES creates a transition between the aircraft and the VED. As such, the Entranceway serves two purposes:
1. It provides the structural interface between the aircraft and the VES.

2. It provides a psychological transition to direct evacuees into the descent controlling zigzag profile of the VED.
The upper curtain of the Entranceway is designed to offer a psychological barrier between the safe confines of the chute and the potential hazards of the immediate outside environment (primarily the height of the descent). The curtain also acts as a natural indicator of the egress route by transitioning into the upper hopper of the chute.
The VE~. The Vertical Descent Device (VED) is hung from the Entranceway.
The VED is a tubular fabric chute provided with internal baffles in a zigzag pattern which control an evacuee's descent by means of friction. A preferred average descent rate of 4-6m/s may be achieved regardlE;ss of the aircraft door sill height.
The descent through the VED is "passive". Therefore, the evacuees require no physical ability; people of substantially all ages and sizes can descend safely. The chute material is preferably 100% nylon which is sprayed with a fire retardant coating.
One of the primary challenges with the VED is stability in wind conditions.
Thus the present invention provides two means of improving the specific performance of the VED in high winds, which can be used either in combination or separately:
1. To restrain the chute with breaking bands until the first evacuee descends (the bands bursting open a s the evacuee descends); and 2. To place cut-outs or openings in the ;side panels of the chute fabric to enable wind to pass through.
The Landing Platforrr~. The landing platform is a small inflatable structure that is fixed to the exit of the VED. The landing platform is also connected to the sill of the aircraft door via two mooring lines. The platform creates a soft landing area for evacuees regardless of the surface underneath (be it water, tarmac or some other undefined material). In addition, the landing platform assists evacuees in moving clear of the chute exit area and away from the aircraft.
The Life Raft. The life raft is a preferred component of the VES whether the system is deployed on land or in the water. On land the life raft remains un-inflated - Ll. ..
and serves as an anchor for the entire system. In a ditching situation the life raft is inflated and will serve as a safe refuge for up to 24i evacuees.
In one aspect, the landing platform consists of an angled inflatable platform which is provided at the base of the chute, which serves as a slide to receive descending passengers and deposit them onto a life raft. A wind deflector is provided between the elevated side of the landing platform and the life raft, in order to maintain the landing platform in position.
Alternatively, the landing platform may be arranged for generally horizontal deployment, with a life raft being fastened to the landing platform at an adjacent position wherein passengers simply disembark from the landing platform onto the adjacent fife raft. The raft may be stored in the un-inflated position either adjacent to the landing platform or under the landing platform.
DESCRI~TI~N C9F THE DRAWINGS
FIGURE 1 is a front eievationaf view of a first embodiment of the invention, in the fully-deployed position and showing a portion of an aircraft fuselage.
FIGURE 2 is a side elevationa! view of the device shown in Figure 1.
FIGURE 3 is a further side elevational view of the same device, for deployment on water.
FIGURE 4a is a side elevational view of 'the entranceway portion of the device.
FIGURE 4b is a front elevational view of the same portion.
FIGURE 4c is a plan view from above of the same portion.
FIGURE 5 is a perspective view of the support frame for the entryway of the device.

_5_ FIGURE 6a is a schematic side elevational view of a further embodiment comprising a rigid support arm for suspending the chutes in the stowed position.
FIGURE 6b is a schematic view of the same element, showing same being deployed.
FIGURE 7 is a schematic view of a further embodiment of the invention.
FIGURE 8 is a schematic view of a still further embodiment of the invention.
FIGURE 9 is a further schematic view of a further embodiment.
FIGURE 10 is a plan view of a landing platform according to the present invention.
FIGURE 11 is a side sectional view of the landing platform.
FIGURE 12 is a schematic side elevational view of an embodiment of the landing platform.
FIGURE 13 is a schematic side elevational view of a further embodiment of the landing platform and associated components.
FIGURE 14 is a schematic side view of a further embodiment of the landing platform arrangement.
FIGURE 15 is a still further embodiment of the landing platform arrangement.
FIGURE 16 is a still further embodiment of the landing platform arrangement.
FIGURE 1a is a schematic view of the device in operation.
FIGURES 18 through 30 comprise photographs showing various aspects and embodiments of the present invention.

DETAILED DESCRIPTION OF 'TFIE INVENTION
Referring to Figures 1 and 2, the invention comprises in general terms a supporting frame and entrance way which serves the dual functions of supporting the device from an aircraft frame, and providing an entryway for passengers departing the aircraft to enter into the escape chute; a vertical fabric chute; a landing platform to receive passengers at the base of the chute; and an inflatable life raft for use in water deployment.
The escape chute is adapted from conventional or prior art marine or aircraft escape chutes which are designed for vertical deployment. Typically, such chutes comprise a tubular fabric outer casing, with angled internal baffles in a zigzag pattern for slowing the descent rate of passengers. Preferably, a generally flat fabric panel is either attached to the chute or is integral therewith, to provide stability to the chute and a convenient means for sequentially lengthening the chute upon deployment depending on the distance from the aircraft hatch to ground level (since this distance may vary depending on the positioning of the aircraft upon landing).
The chute and associated fabric components (including the landing platform, life raft and in some cases the inflatable support frame and entranceway) are intended to be stowed in a collapsed position such as within a dedicated compartment within the aircraft.
Figure 3 illustrates the present invention in a water deployment situation, in which only a short portion of the chute is deployed, for depositing passengers directly into a life raft.
An inflatable entranceway and support frame is illustrated in Figures 4a, 4b, 4c and 5. fn this embodiment, this component of the system comprises a frame work formed of inflatable tubes. Such inflatable tubes may be inflated by one or more gas cartridges which are released upon deployment of the device.
Inflatable tubes and associated inflation arrangements of this type are in general known and are not described or illustrated in detail herein. Preferably, the tubes are formed from a heavy gas-impermeable fabric such as rubberized nylon. The lower part of the framework is composed of larger-diameter tubes for greater support, relative to the upper portion of the framework. The framework includes lower bracing members which contact the aircraft half at a position below the hatch to provide structural support. Preferably, the frame is stowed prior to deployment in an uninflated and collapsed position within a container or compartment mounted within the aircraft at a position within or immediately adjacent to the associated hatchway.
The container may open directly from the aircraft fuselage skin to the exterior of the aircraft or alternatively the compartment may open towards another location wuch as opening into the hatchway. The framework includes horizontal members for suspending the chute. The tubular members may alsa include suitable inlet and outlet valves including a topping up valve for additional inflation, and one or more pressure relief valves.
An alternative embodiment of the support frame is shown in Figures 6a and 6b. In this version, a rigid arm is provided, which is hinged to the aircraft frame at a position adjacent to the hatch for swinging upwardly when not in use and downwardly when in use to extend generally horizontally outwardly to support the chute. The arm has the shape of an inverted U in the stowed position, comprising opposed vertical side members spanned by an upper cross member, as seen in Figure 6a. In use, the arm is pivoted such that it protrudes outwardly through an open hatch. The chute and associated components such as shrouds and mooring lines, which are not illustrated in Figures 6a or 6b, are permanently attached to the arm, such that upon deployment of the arm the chute may be triggered to descend by a selected amount.
A further embodiment of the chute portion of the invention is shown in Figure 7. In this version, the chute is provided with encircling breaking bands to maintain the chute in a tightly bunched position prior to the first passenger descending therethrough but after the chute has been deployed from the aircraft. The purpose of maintaining the chute in this position is to minimize movement of the chute in windy situations by reducing its exposed surface area. Once passengers begin to descend through the chute, the weight o~f the descending passengers will serve to hold the chute in position. However, prior to this time it is desirable to minimize the exposed surface are of the chute to prevent it from blowing about. The braking bands are fabric, plastic or other bands which encircle the chute to hold in a a bunched position but are designed to burst open at relatively low tension such as about 10-15 pounds. Any suitable number of bursting bands may be selected, although it is contemplated that at least three such bands are required and preferably more, and which are generally evenly spaced along the length of the chute. However, a reasonable limit to the number of bands exists, wherein descending passengers do not pick up sufificient speed between bands to burst them open. The bands may be fastened to the chute by any convenient means, such as stitching or otherwise. Alternatively, a single long band may be wrapped around the chute essentially from top to bottom, containing multiple braking points to release the band. Preferably, the uppermost band is spaced at feast several feet below the top of the chute, in order to permit a descending passenger to pick up sufficient speed to burst the band, even if such passenger is relatively light.
The bands may comprise a relatively sturdy band which includes a "weak link" or alternatively one in which the material itself is relatively weak and capable of easy tearing or rupture.
Figure 8 illustrates a further embodiment of the invention, relating to an alternative approach to minimizing the effect of wind acting upon the chute.
In this version, the backing pane! includes cutaway portions to reduce the exposed surface area. Figure 9 illustrates a different way to achieve the same effect, with circular cut-outs. It will be seen that the cut-outs or cutaway portions may comprise any convenient size or shape, although maximal adv<~ntage will be achieved by the largest possible cut-out portions which still preserve sufficient strength in the backing panel.
Figures 10 and 11 illustrate a landing platform according to the present invention. The platform comprises a generally rectangular frame comprised of inflatable tubes which forms the outer edge of the platform, with a trampoline-like fabric surface stretched across (and above) the frame members to receive passengers. The inflatable frame preferably includes a conventional auto-inflation _g_ system including a gas cartridge and topping up and relief valves.
Conventional handling loops are also included. The platform is fixedly attached to the lower end of the chute. As well, mooring lines fasten the landing platform to the aircraft door andlor the deployment frame.
A version of the landing platform is illustrated in Figure 12. In this version, the platform may be optionally disposed at an angle, such that descending passengers slide off the platform onto a waiting surface. In this version, the life raft is attached by mooring lines to the landing platform, such that upon deployment of the raft may be inflated to include the landing platform within its interior.
Figure 13 illustrates a further variant of the landing platform and associated components. In this variant, the platform is contained within the interior of the raft when aff components are fully deployed, as in the previous embodiment.
Separate mooring lines are provided to fasten the landing platform and fife raft to the aircraft fuselage andlor support frame. A wind deflector is provided, comprising a fabric sheet opposed ends of which are joined to the life raft and the landing platform. In the un-deployed stowed position, the deflector is bunched, while in the deployed position the deflector is held reasonably taut between the frame of the life raft and a portion of the frame of the landing platform. The deflector is intended for use when the system is deployed such that the landing platform is upwardly angled, in order to prevent wind from catching the underside of the platform. Hence, the deflector spans the raft and uppermost part of the deployed platform to prevent wind from entering the concave gap between the angled platform and raft.
A variety of wind deflectors and spoilers may be provided to reduce wind effects or to channel the wind to advantage. For e:~ample, additional wind spoilers or deflectors may be provided on each side of the landing platform at or near the point where it contacts the ground.
In a further version, shown in Figure 14, the raft is attached to the landing platform at a position adjacent to the platform. Figure 14 illustrates the raft in the un-inflated position. In this variant, passengers descend the chute directly onto a platform deployed in a generally horizontal position. The raft may be optionally inflated for a water landing, but otherwise is permitted to remain un-inflated, adjacent to the landing platform. The weight of the uninflated raft serves to stabilize and anchor the system. Figure 15 illustrates a related version, but in which the un-inflated raft is stowed underneath and within the interior of the landing platform. In this version, the raft when inflated would surround the landing platform such that the platform would fit within the interior of the inflated raft.
Figure 16 illustrates a further embodiment of the landing platform system, in which the landing platform is again fastened to the raft such that upon deployment the platform is within the interior of the raft and is positioned at an angle relative to the raft. However, the landing platform is positioned adjacent an edge of the raft such that exiting passengers generally contact a raft buoyancy tube upon sliding off of the lower end of the ianding platform.
Operation of the system will now be described, in part by reference to Figure 17.
2.0 VES Oaerational Procedures 2.1 General The VES is attached to the sill of the aircraft door.
In the stowed configuration the VES has a visible gauge displaying the pressure in both the Landing Platform reservoir and the Life Raft reservoir.
The pressure of all reservoirs should always be within the acceptable pressure range shown on the gauge.
The operation of the VES is linked to the aircraft door.
When the aircraft door is armed, the VES is :simultaneously armed and ready for use.

Arming the aircraft door and checking the prEasure in the reservoirs is part of the pre-flight preparation.
2.2 ~perationai Procedures - Ennergency Landinc~on Ground 1. Visually check through window in emergency exit door to confirm environment in landing zone is suitablE: for evacuation.
2. Open aircraft emergency exit door. The VES will deploy automatically once the opening cycle of the aircraft door is complete.
3. While door is opening confirm shoes are removed from your feet.

4.. View readiness indicator.

5. Jump, feet first, through red target hole to evacuate: keep legs together, toes up and arms across chest during descent.

6. Quickly move away from VED exit after descent.

7. If strong winds are adversely affecting stability of Landing Platform, grab one of the red "SUPPORT HANDLES" clearly marked on either side of the Landing Platform to stabilize the exit area.

8. When all personnel are safely evacuailed, quickly move away from the aircraft.
2.3 Gperationai Procedures -- Ernergenc~ Lan~dina on lllfater (~itchin~) 1. Visually check through window in emergency exit door to confirm environment in landing zone is suitablE; for evacuation.
2. Open aircraft emergency exit door. TI-9e VES will deploy automatically once the opening cycle of the aircraft cloor is complete.

While door is opening confirm shoes are removed from your feet.
4. View readiness indicator.
5. Jump, feet first, through red target hole to evacuate: keep legs together, toes up and arms across your chest during descent.
6. Quickly move away from VED exit aflter descent and seat yourself in an open area on the perimeter of the life raft.
7. When alB evacuees are safely in thE= Life Raft, pull the red handle clearly marked "CHUTE DISC~NNEC'T".
8. Move away from the aircraft.
2.4. ~perational Seetuer~ce 1. When the opening cycle of the aircraft door is complete, the VES
support frame and the VED pack deploy.
2. The top portion of VED stays attached to the support frame and the door sill as the remainder of the pack is reiedsed.
3. The mooring lines stay attached to the door sill.
4. The pack, including the VED, landing platform and life raft drop under g ravity.
5. The inflation system for the landing platform wiif actuate upon contact with the ground. In case of ditching, the inflation system of both the landing Platform and the Life Raft will lae actuated.
6. Readiness indicator will be visible upoin inflation of Landing Platform.

7. Jump to evacuate.
8. Move away from exit area.
To improve wind performance the system includes the possibility that that the raft does not inflate if the evacuation scenario is on land. The un-inflated raft thereby acts as an anchor to stabilize the system in wind. If the aircraft lands in water (ditching scenario) than the raft will inflate and serve its function. For thi;~ purpose, the raft is separately inflated either by a separate manual operation, or via a sensor which detects a water or dry land landing.
To add to the anchor effect of the raft {extra weight) the invention further comprises a means for dropping part of the aircraft door (or other weight from the aircraft). The member which drops down would likely not include the entire door itself, but perhaps a portion of the door mechanism or door fining or some other park of the aircraft close to the door.
Although the present invention has been described by means of detailed descriptions of embodiment, of the invention, as well as representative drawings and photographs, it will be seen by those skilled in the relevant art that such description is merely illustrative of the present invention and is not intended to limit the scope of the invention in any respect. The full scope of the invention is more completely described in the claims of this specification, including any functional or mechanical equivalents to any elements described or characterized in the claims.

Claims (11)

1. An aircraft deployment system substantially as described and illustrated herein.

2. A passenger escape chute for vertical descent from an aircraft, including an entrance way comprised of a rigid or semi-rigid framework formed from inflatable tubes.

3. An aircraft descent system as defined in claim 2, wherein said entranceway further comprises a curtain for at least partially shielding passengers view upon entering the entranceway.

4. A system as defined in claim 1, comprising a rigid arm having a hinge at a lower end for pivotal mounting to an aircraft, for supporting said chute.

5. A system as defined in claim 1, comprising a vertical fabric chute having an array of braking bands encircling said chute for maintaining at least a substantial length of said chute in a bunched position prior to deployment, said bands having a sufficient low breaking strength to burst upon descent of the first passenger through said chute.

6. A system as defined in claim 5, wherein said bands comprise weak link breaking bands.

7. A system as defined in claim 1, wherein said chute includes a fabric supporting panel, said panel including cutaway regions to minimize the sail area of said panel.

8. A system as defined in claim 1, comprising an inflatable landing platform fastened to said chute, and an inflatable raft engaged by mooring lines to said landing platform, said raft being separately inflatable from said platform to serve as a stabilizer for dry-land use.

9. A system as defined in claim 8, further comprising a fabric wind detector between said platform and raft arranged for unfurling when said platform is disposed at an angle relative to said raft upon deployment, for deflecting wind from entering the space between the upraised portion of said platform and said raft.

10. A system as defined in claim 8, wherein said raft is fastened to said platform at a position adjacent to said platform.

11. A system as defined in claim 8, wherein said raft is fastened to said platform at a position underneath said platform when in the un-deployed position, for deployment to contain said platform within the interior of said raft.