EP0868342A1

EP0868342A1 - Marine escape systems

Info

Publication number: EP0868342A1
Application number: EP96942443A
Authority: EP
Inventors: Richard Edward Bell; Iain Henry Mclean; Peter John Phipps
Original assignee: Wardle Storeys Safety and Survival Equipment Ltd
Current assignee: Wardle Storeys Safety and Survival Equipment Ltd
Priority date: 1995-12-19
Filing date: 1996-12-12
Publication date: 1998-10-07
Anticipated expiration: 2016-12-12
Also published as: GB2338219A; EP0868342B1; NO982792L; HK1017321A1; NO20052098L; NO982792D0; DE69621947T2; CA2237999A1; JPH11513948A; DE69621947D1; JP3314086B2; CN1205673A; NO319595B1; WO1997022514A1; AU713020B2; GB9920249D0; CN1079763C; GB2338219B; CA2237999C; DK0868342T3

Abstract

A marine escape system has a passage (13; 30, 31, 32) extending between an evacuation point on a vessel and an inflatable life raft. The passage (13; 30, 31, 32) is arranged vertically and is connected to a succession of hoops (15). The connection between at least one of the hoops (15) and the life raft is by means of flexible elongate members (24) of differing flexibility. These are held in tension so that, as the life rafts move on swell, the passage extends and retracts from the lower end first. This allows the passage (13; 30, 31, 32) to have only one exit which can be within a life raft (12) so that persons can evacuate from the ship without ever being exposed to the elements. The passage may include a helical tube (13) or a tube (30, 31, 32) with angled panels (40).

Description

MARINE ESCAPE SYSTEMS

The invention relates to marine escape systems.

A marine escape system is used for evacuating people from a

structure at sea in the event of an emergency. Such a

structure may be an oil rig or a ship.

One form of marine escape system includes liferafts into which

the people are evacuated. Since, when liferafts are deployed

on water, there is usually a significant difference in height

(freeboard) between the point on the structure from which the

people are evacuated and the liferafts, it is necessary to

provide some form of passage between the two.

It is known to provide an angled chute, which may be formed

from inflatable members, extending between the evacuation

point and the liferafts. The chute can extend either direct

to the liferafts or to an inflatable floating structure to

which the liferafts are attached. In some vessels, the

freeboard may be 14-15 metres and so the chute is of

significant length. Recent sinkings of ships have placed greater emphasis on the

need to evacuate marine structures quickly in the event of an

emergency It is Ixkely to be a requirement that any sea¬

going vesεel must be able to evacuate 400 people m 17 minutes

40 seconds In addition, it is likely to be a requirement

that any marine escape syεtem must be able to operate in force

six weather which will include a 3 metre swell and that the

marine escape system must be usable for a considerable period

of time with the vessel side-on to the sea

An angled chute is not readily able to meet such a

requirement Since the chute projects from the side of a

vessel it requires stabilization in order to prevent

significant lateral movements m heavy weather Further, to

accommodate such weather, the chute must be comparatively

rigid and this can increase significantly the bulk of the

chute

Marine escape systems have alεo been proposed in which the

connection between the evacuation point and the inflatable

liferafts is via a tube containing a helical slide passage

A person entering the passage at the escape point travels in a helical path along the passage and emerges at an exit at the

lower end of the tube

A tube requires less stabilization than a chute against

lateral movement in heavy weather However, the tube haε the

problem of accommodating swell which, as mentioned above, may

alter the freeboard of a vessel by six or more metres

It has previously been proposed to accommodate this by making

the tube of flexible material with a maximum length sufficient

to accommodate the swell The tube hangs from the evacuation

point on the structure and haε excess length heaped on a

platform to which people are evacuated when the swell is lesε

than the maximum As the space m between the platform and

the evacuation point varies, more or less of the tube is

either extended from or piled into the heap on the platform

It is a problem with such an arrangement that no single exit

can be provided In order to overcome this problem, such

tubes have previously been provided with a plurality of exits

spaced along their length, with evacuated persons emerging

from the exit closest to the platform at the time they reach

the platform This is not, however, satisfactory because a person may exit too soon or the position of the platform may

change to make a selected exit suddenly inappropriate

According to the invention, there is provided a marine escape

system comprising a passage for perεonε and having an entrance

at one end and an exit at an end opposite said one end, at

least one support for the passage being provided between the

entrance and the exit, the support being suspended by at least

one first elongate elastic member, at least one second

elongate elastic member extending from the εupport towards the

exit, the at least one second elongate elastic member having

a greater elasticity than the at least one first elongate

elastic member, so that a portion of the passage between the

exit and the support is extensible and contractible before the

extension and contraction of a portion of the pasεage between

the entrance the εupport, the passage being extensible and

contractible to accommodate changes in the spacing between the

entrance and the exit

By varying the length of the tube between the entrance and the

ex t, a swell can be accommodated while maintaining a single

exit According to a second aspect of the invention, there is

provided an escape chute comprising an elongate tube which is

deployed generally vertically and a succession of spaced

members within the tube and defining, with the tube, a path

for the passage of a person through the tube

The following is a more detailed description of some

embodiments of the invention, by way of example, reference

being made to the accompanying drawings in which. -

Figure 1 is a side elevation of a ship showing schematically

a marine escape system including two escape chutes leading

from an emergency exit to liferafts deployed on the sea,

Figure 2 is a side elevation of a part of one of the escape chutes,

Figure 3 is a perspective view of part of the escape chute of

Figure 2 ,

Figure 4 is a cross-section through the escape chute of

Figures 2 and 3,

Figure 5 is an elevation of one side of a right hand side cell

of an alternative form of escape chute,

Figure 6 is a front elevation of the right hand cell shown in

Figure 5, Figure 7 is an elevation of the other side of the right hand

cell of Figures 5 and 6,

Figure 8 is a rear elevation of the right hand cell of Figures

5 to 7, Figure 9 is a schematic view of an outer wall of the right

hand cell of Figures 5 to 8 ,

Figure 10 is a schematic view of the slide path assembly of

the right hand cell of Figures 5 to 9,

Figure 11 is a partial section of the right hand cell of

Figures 5 to 10 showing the slide path and the outer wall in

an extended dispoεition,

Figure 12 is a similar view to Figure 11 showing the outer

wall in a collapsed disposition,

Figure 13 is a similar view to Figure 12 but showing the whole

of a right hand cell with the outer wall in a collapsed

disposition,

Figure 14 is an elevation of one side of a left hand cell of

the alternative form of chute,

Figure 15 is a front elevation of the left hand cell, Figure 16 is an elevation of the other side of the left hand

cell,

Figure 17 is a rear elevation of the left hand cell of Figures

14 to 16, Figure 18 is a similar view to Figure 14 but showing the outer

wall of the left hand cell of Figures 14 to 17 in a collapsed

disposition,

Figure 19 is an elevation of one side of a bottom cell of the

alternative escape chute,

Figure 20 is a front elevation of the bottom cell of Figure

19,

Figure 21 is an elevation of the other side of the bottom cell

of Figures 19 and 20,

Figure 22 is a rear elevation of the bottom cell of Figures 19

to 21, and

Figure 23 is a similar view to Figure 19 but showing the outer

wall of the bottom cell of Figures 19 to 22 in a collapsed

disposition.

Referring first to Figure 1, the marine escape system

comprises two emergency exits 10 each leading to a respective

escape chute indicated generally at 11 Each escape chute

terminates at a respective liferaft 12 with two further

liferafts 12 also being provided It will be appreciated that

the marine escape system is normally held in a container at

the side of the ship and deployed in an emergency, in a manner to be described below Referring now to Figures 2, 3 and 4, each escape chute 11

comprises a closed tube 13 of foldable material (such as a

fabric) formed into a helix The tube 13 may be provided with

stiffening bands 14 at spaced intervals along its length m

order to hold the tube 13 open

The tube 13 is supported by a plurality of hoopε 15 εpaced

apart along the length of the tube 13 Aε seen in Figure 2,

there are eleven hoops 15, but there may be more or less hoops

as required Each hoop 15 is made from a rigid alloy or a

carbon fibre material A typical hoop diameter might be 2 3

metres

As best seen in Figures 3 and 4, each hoop is provided with

six fixing points 16 equiangularly spaced around the exterior

of the hoop 15 The purpose of these will be described below

As will be seen m Figures 2, 3 and 4, each hoop 15 is

positioned at a point along the length of the tube 13 where

the axis 17 of the tube lε at a maximum spacing from the axis

18 of the hoop The tube 13 is held m this position by five

flexible but inelastic elongate members 19 and seven flexible

and elastically elongatable members 20 The inelastic members 19 may be cords while the flexible members 20 are preferably

formed from a resilient elastomeric material

The inelastic members 19 extend between equiangularly spaced

points 21 on the portion of the periphery of the tube 13 lying

between two parallel planes, one extending through the tube

axis 17 and the other extending through the hoop axis 18 and

both being normal to a hoop radius extending between the hoop

axis 18 and the tube axis 17 This is the portion of the tube

13 that faces the hoop axis 18 In this way, the inelastic

members 20 fix the maximum spacing between the tube axis 17

and tube axis 18 so preventing the tube 13 moving any closer

to the hoop 15

The elastic members 20 are also connected between the tube 13

and the hoop 15 Two of the elastic members 20 extend from

diametrically opposite points 22 on the periphery of the tube

13 and lying in a plane including the tube axis 17 and normal

to a radius extending from the hoop axis through the tube

axis The remaining elastic members 20 are equiangularly

spaced around the periphery of the tube 13 between these two

points 22 The elastic members 20 thus allow the tube 13 to move εo that

the spacing between the axis of the tube 17 and the axis of

the hoop 18 decreases. The elastic members 20 are permanently

in tension and εo they provide a force tending to restore the tube 13 to the position shown m Figure 3 This may be a

position in which the helical tube 13 has a helix angle of

30° .

The hoopε 15 themselves are alεo interconnected by flexible

members of two kinds; inelastic flexible members 23 and

elastic flexible members 24.

The inelastic flexible members 23 extend from a εupport 25 at

the top of the escape chute 11 and the sixth hoop 15, as seen

in Figure 2. There are six members 23 equiangularly spaced

around these hoops 15 and connected at each hoop 15 to an

associated one of the fixing points 16 Thus, the inelastic

flexible members 23 fix the maximum spacing between the first

and sixth hoopε 15.

The sixth hoop 15 is connected to an associated liferaft 12 by

the elastic flexible members 24. There are three different

types of elastic flexible member 24, the types having different elasticities. The first elastic members 24a are the

least elastic and they extend between the sixth hoop 15 and

the eighth hoop 15. There are six members 24a and they are

attached to the fixing points 16 on the sixth, seventh and

eighth hoops 15

The second elastic flexible members 24b are more elaεtic than

the first elastic flexible members 24a. There are six of

these members 24b and they extend between the eighth hoop 15

and the tenth hoop 15 and are connected to the fixing points

16 on these hoopε.

The third elastic flexible members are connected between the

tenth hoop 15 and the associated liferaft 12. They are more

elastic than the second elastic flexible members 24b There

are six of these members 24c and they are connected to the

fixing points 16 on the tenth and eleventh hoops 15 and to

fixing points (not shown) on the liferaft 12.

A typical first elaεtic flexible member 24a might have a

diameter of 19mm and extend in excess of 4000mm under a load

of about 7.5N. Each second elastic flexible member 24b might

typically have a diameter of 16mm and extend in excesε of 4000mm under a load of about 5 5N Each third elaεtic

flexible members 24c might have a diameter of 12 5mm and

extend in excess of 4000mm under a load of 3 5N

The outside of this structure may be covered by a fabric tube

(not shown) of generally the same diameter aε the hoops 15

Each exit 10 is connected to the εupport 25 at the upper end

of the escape chute 11 This provides an exit from the ship

and leads to the entrance to the escape chute 11 at the upper

end of the escape chute 11

The liferafts 12 are formed by inflatable tubes 26 and are

provided with a fabric cover 27 The liferafts are generally

rectangular in plan view and, as shown in Figure 1, are held

together in a rectangular array Each escape chute 11

provides at its lower end an exit within an associated one of

the liferafts 12

In use, the liferafts 12 are deflated and are held with the

escape chutes 11 m a container mounted at the exits 10 on the

ship It will be appreciated that the escape chutes 11

require very little space because the hoops 15 will collapse to lie on top of one another and the fabric of the tube 13 can readily be collapsed The members 23,24 will alεo collapse

into a comparatively small space

In an emergency, the liferafts 12 and the escape chuteε 11 are

ejected from the container and the exits 10 opened As they

deploy, the liferafts 12 are inflated from a source of gas

under pressure (not shown) in conventional fashion The

liferafts 12 are provided with water pockets (not shown)

which, as the liferafts 12 hit the sea, fill with water The

weight of the liferafts 12 and the length of the inelastic

members 23 and the elastic members 24 are chosen so that, in

a calm sea and with the ship normally loaded, the inelastic

members 23 are fully extended and the elastic members 24 are

under tension As indicated above, typical elastic members 24

may provide between them an extension m excess of 12000mm

In this case, the arrangement may be εuch that in calm sea the

flexible members 24 are extended by 6000mm

The extension of the members 24 increases the spacing between

the sixth hoop 15 and the associated liferaft 12 This

causes the tube 13 to have an increased helix angle, aε seen

m Figure 2 This in turn causes straightening of the tube and thus extension of the flexible elastic members 24

connecting the tube 13 to the hoops 15 with the tube 13 moving

towards the axis 18 of the hoopε 15

When deployed m this way, perεonε can enter the entrance at

one end of the tube 13, slide through the tube in a helical

path and emerge within the liferaft They are, therefore,

never exposed to the outside elements in the whole of their

travel between the ship and a liferaft 12

Sea swell will cause the liferafts 12 to move up and down

relative to the exits 11 so increasing and decreasing the

freeboard of the ship This is accommodated by extension and

retraction of the elastic members 24 and by extenεion and

retraction of the tube 13 The third elaεtic members 24c will

extend first followed by the second elastic members 24b and

followed by the first elastic members 24a The weight at the

end of the tube 13, provided by the liferafts 32, is

sufficient to cause this extenεion without the liferafts 12

lifting out of the sea The position of the axis 17 of the

tube 13 will also change, with such changes being accommodated

by the flexible members 20 As this occurs, the helix angle

of the tube 13 will vary. It will be appreciated that there are a number of variations

that can be made to the marine escape system deεcribed above

with reference to the drawings .

There need not be two escape chutes 11; there could be one or

three or more. The or each eεcape chute 11 need not terminate

within a liferaft 12; it could terminate at a floating

platform to which liferafts are attached.

In an alternative arrangement, the tube 13 may split at a

point along its length into two parallel tubes εo that persons

evacuating the ship can pass successively down one and then

the other of the tubes .

The connections between the hoops need not be formed by

flexible members 24, they could be formed by any suitable

extendible member such as a spring.

Although the arrangement described above is elastically extendible and retractible only from the sixth hoop 15 to the

liferaft 12; it could be elastically flexible all the way

along its length or between the liferafts and hoops other than

the sixth hoop 15. It will alεo be appreciated that the weight of the liferafts

12 at the end of the escape chutes 11 tend to keep the chutes

in a vertical disposition This minimizes the requirement for

any stabilization of the position of the escape chuteε 11

relative to the ship

The escape path for evacuees need not be a helical tube, it

could be an open-topped helical chute or a tube containing a

succeεεion of alternately oppoεitely facing panelε spaced

along the length of the tube, each panel being angled relative

to the length of the tube A person entering the tube slideε

down one panel and then turns to slide down an oppositely

facing panel and so on until the end of the tube is reached

In this case, the panels may be of flexible material to

accommodate extension and retraction of the tube

Referring next to Figures 5 to 22, there will now be described

an alternative form of the escape chute shown in Figure 1

In this embodiment, the eεcape chute is formed from three

different kinds of cell A left hand cell 30 shown in Figures

5 to 13, a right hand cell 31 shown m Figures 14 to 18 and a

bottom cell 32 shown in Figures 19 to 23 The right hand and left hand cells 30,31 are joined end to end alternately to

form the chute, in a manner to be described in more detail

below, and the bottom cell 32 is attached at the end, again in

a manner to be described in more detail below.

Referring first to Figures 5 to 13 , the left hand cell 30 is

formed from a cell wall 33, beεt seen in Figure 9, and a slide

path 34, best seen in Figure 10. The cell wall 33 is, as seen

in Figure 9, generally cylindrical and formed of a high

strength waterproof fabric. As best εeen in Figureε 5 to 8,

the cell wall 33 haε an upper edge 35 provided with a

circumferentially εpaced series of loops 36. The cell wall 33

also has a lower edge 37 with εimilar spaced loops 38. A

series of tubular pockets 39 extend around the cell wall 33

intermediate the upper edge 35 and the lower edge 37 to form

an interrupted annular passage around the cell wall .

The function of the loops 36,38 and the pockets 39 will be

deεcribed below.

The cell wall 33 containε a slide path 34, beεt seen in Figure

10. The slide path 34 is also formed from strong waterproof

fabric . The slide path 34 comprises a back panel 40 which is generally

elongate with a rounded upper end edge 41 and a convexly

curved εide edge 42 The edge of the εide of the back panel

40 oppoεite the side edge 42 is straight and the lower edge 44

of the back panel 40 opposite the upper end edge 41 is also

straight A diverter panel has an edge connected to the

straight edge 43 of the back panel 40 and lies m a plane that

subtends an obtuse angle to the plane of the back panel 40

An outer skirt panel 46 curves between a lower portion of the

outer edge 47 of the diverter panel 45 and a lower portion of

the side edge 42 of the back panel The back panel 40, the

diverter panel 45 and the outer skirt 46 thuε between them

form a converging enclosed pathway or pocket This terminates

in an aperture 48

The slide path 34 is connected inside the cell wall 33 in the

following way

The upper end edge 41 of the slide path 34 is connected to the

interior εurface of the cell with the apex of thiε edge 41

being adjacent the upper edge 35 of the cell wall 33 Thiε

connection continues around the upper end edge 41, the side

edge and the outer edge 47 of the diverter panel 45, until approximately the level of the pocketε 35. In addition, the

outer εkirt 46 has an upper edge 50 that is also connected to

the interior of the outer of the cell wall 33 also roughly at

the level of the pockets 35

Thuε, aε εeen in Figureε 5 to 8 , the back panel 40 extends

diagonally across the cell wall 33 between the upper edge 35

and the lower edge 37 As seen in Figure 7, the diverter

panel 45 is at an obtuse angle relative to the back panel 40

The funnel outlet 49 extends downwardly beyond the lower edge

37 of the cell wall 33. In this way, as seen in Figure 13,

the lower part of the cell wall 33 can be collapsed upwardly

without affecting the disposition of the slide path 34. The

purpose of this will be described below.

The right hand cell 31 will now be described with reference to

Figureε 14 to 18 Aε εeen m theεe Figures, the cell is

largely identical to the left hand cell 30 and the common

partε will not be described in detail and will be given the

same reference numeralε. The difference between the right

hand cell 31 and the left hand cell 30 is that, in the right

hand cell 31, the slide path 34 is rotated by 90° relative to

the loops 36,38 as compared to the slide path 34 of the left hand cell 30 This allows the loops 35,38 to form a passage

in a manner to be deεcribed below

The bottom cell 32 is formed by an annular cell wall 55 having

an upper edge 56 provided with loops 57 which are the same aε

the loops 36 on the upper edge 35 of the cell wall 33 of the

left hand cell 30 The cell wall 55 has, however, no pockets

35 and no loops on its lower edge 58 The length of the cell

wall 55 between the upper edge 56 and the lower edge 58 is

longer than the length of the cell wall 33 of the left hand

cell 30 between its upper edge 35 and lower edge 37 The cell

wall 55 contains a slide path 59 which is identical to the

slide path 34 in the left hand cell 30 and is connected to the

cell wall 55 in the same way as the slide path 34 is connected

to the left hand cell 30 Thus, as seen in Figures 18 to 22,

the funnel outlet 49 projects only a short distance below the

lower edge 58 of the cell wall 55 However, the back panel 40 may be perforate to allow water to drain through the panel 40

The chute is formed by connecting together left and right hand

cells 30,31 alternately until a chute of the required length

haε been formed The cells are so arranged that the back

panel 40 of each slide path 34 is skewed by 90° relative to the preceding and succeeding back panels 40. The skewing iε

εucceεsively in the same sense (either clockwise or

anticlockwise) .

The cells 30,31 are interconnected by hoops (not shown) . The

loops 38 at the lower edge 37 of one slide path 34 (of a left

or right hand cell 30,31) fit between the εpaces of the loops

36 of the upper edge of the next slide path 34 (of a right or

left hand cell 31,30) . There iε thus formed a continuous

tubular passage through which a hoop extends to form the

connection. The hoops may, for example, be made of metal.

The bottom cell 32 is connected to the lowermost left hand or

right hand cell 30,31 in the same way; by a hoop passing

through the passage formed by the loops 36,38.

A hoop 53 iε also passed through the tubular pockets 39

between the upper and lower edges 35,37 of each cell wall 33.

The effect of theεe hoopε 52,53 iε to hold the cell walls 33,

55 open while permitting them to be collapsed.

The hoops 52 at the upper and lower edges 35,37 of the cell

walls (but not the intermediate hoops 53) are connected together by elastic members which are arranged in the same way

as the elastic members 19 connecting the hoopε 15 n the

embodiment deεcribed above with reference to Figureε 2 to 4

The escape chute so formed is connected between a ship and a life raft 12 m a manner of the escape chute described above

with reference to Figures 2 to 4

This embodiment of the eεcape chute forms, m eεsence, a

εpiral path between the uppermost cell 30,31 and the bottom

cell 32 A person entering the uppermost cell 30,31 initially

sits on the back panel 40 of the first slide path 34 Aε the

person travels down the back panel 40, they engage the

diverter panel 40 and this twists them in anticlockwise

direction. They then pasε through the funnel outlet 49 to

engage the back panel 40 of the next succeeding cell 30,31

which is skewed by 90° to the back panel 40 the person haε

just left The effect of the funnel outlet and the εkewed

arrangement of the back panels 40 is to cause the person to

slow down by friction engagement with the material of the

slide path and by the constriction provided by the funnel

outlet A person travelling through the escape chute thuε

reaches a safe speed at which the person paεεes m a spiral

path through succeeding slide paths 34 until the bottom cell 32 is reached. Aε the person leaves the bottom cell 32

through the funnel outlet 49, they enter the life raft 12 as

described above w th reference to Figureε 1 to 4

As the spacing between the life raft 12 and the εhip varieε,

such variation is accommodated by the collapse and extension

of the chute under the control of the flexible members 20

which progreεεively collapses the chute from the bottom cell

32 upwards, as described above with reference to Figures 1 to

As a result of the way in which the slide paths 34 are

connected to the cell walls 33,55, such collapsing of the

walls 33,55 does not collapse the slide pathε 34 Aε the

escape chute length getε shorter, they merely concertina into

one another so that, aε a person leaves a funnel outlet 49 of

one cell 30,31 they engage the back panel 40 of the next

succeeding cell 30,31 at a position lower down the back panel

40 than the person would if the cells 30,31 were fully

extended

It will be appreciated that there are a number of variations

that can be made to this second form of escape chute The slide path 34 need not be formed as described. It could have

any shape which guides and controls the path of a person

through the chute. The cells 30,31,32 need not be connected

by loops 36,38 aε deεcribed above, they could be connected in

any suitable way. The cell walls 33,55 need not be

continuous,- they may include cut-outs.

Claims

CLAIMS.

_{1 A} marine escape system comprising a passage (11) for

persons and having an entrance (10) at one end and an ex t

(12) at an end opposite said one end, at least one support

(15) for the passage being provided between the entrance and

the exit, the support being suεpended by at leaεt one firεt

elongate elaεtic member (24) , at least one second elongate

elastic member (24) extending from the support (15) towards

the exit, the at least one second elongate elastic member (24)

having a greater elasticity than the at least one first

elongate elastic member (24) , so that a portion of the pasεage

(11) between the exit and the εupport (15) lε extenεible and

contractable before the extension and contraction of a portion

of the passage (11) between the entrance the support (15), the

passage being extensible and contractible to accommodate

changes in the spacing between the entrance and the exit

2 A syεtem according to claim 1 wherein a further support

(15) is provided between the firεt mentioned εupport (15) and

the exit (12) , the at least one second elongate elastic member

(24) being connected between the first-mentioned and the

further supports (15) , at least one third elongate elaεtic member (24) extending from the further εupport (15) towardε

the exit (12) εo that the paεsage (11) extends and contractε

initially between the exit (12) and the further support (15)

and then between said support (15) and the first-mentioned

support (15) and then between the first-mentioned support (15)

and the entrance (10)

3 A syεtem according to claim 1 or claim 2 wherein the

at least one first elongate elastic member (24) is connected

between an upper support (15) and the first-mentioned support

(15) , said upper support (15) being spaced from the entrance

of the passage (11) , the connection between said entrance and

said upper εupport (15) being non-elastic

4 A system according to claim 3 wherein the connection

between said entrance and said upper support comprises at

least one elongate inelastic member (23)

5 A system according to any one of claims 1 to 4 wherein the or each support is formed by a hoop (15) extending around

the passage 6 A system according to claim 5 when dependent on any one

of claims 2 to 4 wherein a plurality of hoops (15) are

provided at spaced locations along the passage (11) between

the entrance and the exit, said hoops (15) forming said

supports

7 A system according to any one of claims 1 to 6 wherein

each at leaεt one elongate elastic member (24) comprises a

plurality of said elongate elastic members (24) , each member

(24) extending generally parallel to the length of the passage

(11) and the members being spaced around the passage (11)

8 A system according to any one of claims 1 to 7 wherein

the passage (11) is formed from a tube of foldable material

9 A system according to any one of claims 1 to 8 wherein

the passage comprises a helical chute (13) extending from the

entrance to the exit

10 A system according to claim 9 wherein the chute is a

closed helical tube (13) 11. A system according to claim 9 or claim 10 when

dependent on claim 8, wherein the helical tube (13) is

connected to the hoops (15) to position the helical chute

relative to the hoops

12. A system according to claim 11 wherein the helical

chute (13) , as the chute passes through at least one hoop (15)

has the centre line thereof eccentrically arranged relative to

the axis of the hoop (15) , the connection between the helical

chute (13) and the hoop (15) allowing the centre line of the

helical chute (13) to move relative to the axis of the hoop

(15) between a maximum spacing an a minimum spacing to

accommodate extension and retraction of the helical chute

(13) .

13. A system according to claim 13 wherein, at said at

least one hoop (15) , a plurality of angularly spaced flexible

connections (19,20) extend between the hoop (15) and the

helical chute (13) , the longer connections (19) being

inextensible to limit the maximum spacing of the centre line

and the axis and the εhorter connections (20) being

elastically extenεible to permit the centre line to move

towardε the axis. 1₄ A system according to claim 9 wherein the passage ⁽11⁾

includes a succession of alternately oppoεitely εpaced facing

panelε (40) spaced along the length of a tube (30) each panel

(40) being angled relative to the length of the tube

15 A system according to claim 14 wherein at least some

of the panels (40) are made from an elastically extendible

material to accommodate extension and retraction of the tube

16 A system according to any one of claims 1 to 15 wherein

the exit is on an inflatable structure

17 A syεtem according to claim 16 wherein the inflatable

structure is a liferaft (12) , the tube exit being within the

liferaft

18 An escape chute comprising an elongate tube (30,31,32)

which lε deployed generally vertically and a succeεsion of

spaced members (34) within the tube and defining, with the

tube, a path for the paεsage of a perεon through the tube (30, 31,32) . 19 An escape chute according to claim 18 wherein the

members (34) are arranged in succeεεion along the tube

(30,31,32) such that a person passing through the tube

(30,31,32) contacts the memberε (34) m succession

20 An escape chute according to claim 19 wherein each

member (34) defines a slide path including a component (40)

tranεverεe to the axis of the tube (30,31,32)

21 An escape chute according to claim 20 wherein the

transverse path component (40) of each member (34) is rotated

about the axis of the tube relative to the transverse path

components (40) of the preceding and succeeding members (34)

22 An escape chute according to claim 21 wherein

successive transverse path components (40) ae rotated in the

same sense by 90° relative to one another so that the path is

a spiral path

23 An escape chute according to any one of claims 20 to

22 wherein each transverse component of the slide path is

formed by a panel (40) extending transversely across the tube

the panel (40) having an upper edge (41) connected to the tube (31,31,32) and a lower edge (44) εpaced from the tube

(30,3₁,32) to define an aperture leading to the next panel

24 An escape chute according to claim 22 and claim 23

wherein each panel (40) has spaced first and second side edgeε

(42,43) , at least a portion of the first side edge (42) being

connected to the tube (30,31,32) and the second side edge (43)

being connected to a diverter panel (45) which lε connected to

the tube (30,31,32) and which lies m a plane at an obtuεe

angle to the plane of the aεsociated transverse panel (40) ,

the diverter panel (45) being arranged to impart to a person

a twist in the same sense as the relative rotation between

successive panels (40)

25 An escape chute according to claim 23 or claim 24

wherein a skirt panel (46) extends around a lower portion of

each transverse panel (40) to form, with the panel (40) , a

pocket terminating at a lower end thereof m sa d aperture

(48)

26 An escape chute according to claim 25 wherein each

skirt panel (46) has an upper edge (50) connected to the tube

(30,31,32) and a lower edge forming an edge of said apertuie 27. An escape chute according to claim 26 wherein each

transverse panel (40) is connected to the tube (30,31,32) only

along that portion of the edge (41) of the transverse panel

(40) that is above the line along which the upper edge (50) of

the asεociated skirt panel (46) is connected to the tube

(30,31,32) so that the portion of the tube (30,31,32) below

the upper edge (50) of the εkirt panel can collapse upwardly

without collapsing the associated path member (34) .

28. An escape chute according to any one of claims 23 to

27 wherein at least one of said transverse panels (40) is

perforate .

29. An escape chute according to any one of claims 23 to

28 wherein a funnel outlet (49) depends from each aperture

(48) to provide a vertical component of said path (34) .

30. An eεcape chute according to claim 29 wherein each

funnel outlet (49) is εized to fit closely around a person

passing therethrough εo that the speed of the perεon is

arrested during such paεεage. 31. An escape chute according to any one of claims 18 to

30 wherein the tube is formed from a plurality of annular

walls (30,31,32) of flexible material, each wall surrounding

an associated member, the walls being connected end-to-end to

form εaid tube.

32. An escape chute according to claim 31 wherein a hoop

(53) extends around the connection between successive walls

(30, 31, 32) .

33. An escape chute according to claim 32 wherein each wall

(30,31,32) has an upper edge (35;56) and a lower edge (37;58),

each said edge including a plurality of circumferentially

εpaced loops (36;57) , the loops (36,-57) of each said edge

(35 ;56 ,- 37 ;58) forming, with the loops (36;57) of an adjacent

edge (35 ;56 _;37 ;58) of an adjacent wall (30,31,32) , a passage which receives said hoop (53) .

34. An escape chute according to claim 32 or 33 wherein at

least some of the wallε (30,-31,-32) have an additional hoop

(53) extending therearound at a position spaced between said

connections . 35 An escape chute according to claim 34 when dependent

on claim 27 wherein said additional hoop (53) is at a position

level with the connection of the skirt panel (46) with the

wall (30, 31, 32) .

36 A system according to any one of claims 1 to 9 wherein

the pasεage is formed by an escape chute according to any one

of claims 18 to 35