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5.Parachutes
on Very Low Altitude Barrage Balloons
There
are two types of parachutes in use on VLA balloons. One parachute is designed to
tow the cable and bomb over the wing of an enemy aircraft and is referred to as
the Towing Parachute. The other is designed to stabilise the various A.A.D. bomb
designs as the towing parachute pulls it through the air this is known as the
Stabilising Parachute.
In
general there are two types of Stabilising Parachute:
AD/B No.1 Mark II and 2. AD/B No.1 Mark III.
and
Either of these will work with the Bomb H.E., A.A.D., No.4 Mark IV or the Bomb
H.E., A.A.D., No.6-A Mark II/
AD/B
No.1 Mark II Stabilising Parachute
Stabilising
Parachute Container
This
has a parachute and streamer that are contained in a cylindrical metal container
about 2 ¼ inches long and 3 ½ inches in diameter,(5.75 cm X 8.9 cm). Both ends
of the container are sealed with one joint being weaker than the other and the
weak joint is designed to separate at the seam when sufficient tension is
applied. A split skirt containing a rubber sorbo ring projects from the weak end
of the container. It is fitted over the bomb magazine holder and held there
using a jubilee clip. The groove in the skirt fits over a corresponding ridge on
the bomb magazine holder. The weak end of the container has two holes, one in
the centre through which the stabiliser strop passes and the other between the
rim and the split skirt. The latter is flanged inwardly to take a cork gland
through which the arming wire passes. The strong end of the container has an eye
to which the long shackle is attached.
Stabilising
Parachute and Streamer
The
container houses a stabilising parachute 7 ½ inches in diameter (19.05 cm) and
a 24 inch (61 cm) cotton streamer. The streamer is attached to the parachute
shrouds. A stabiliser strop made of flexible wire rope with a long loop at one
end and a short loop at the other end is fastened with a lark’s head knot to
the short loop to the cotton streamer. The long loop extends through the central
hole at the weak end of the container
and is fastened by a lark’s head knot onto the lug of the bomb magazine
holder. An arming wire which is an extension of the stabiliser strop from the
short loop passes through the cork gland in the weak end of the container and
terminates in an arming pin extension.
Shock
Absorber Strop
The
shock absorber strop is approximately 15 inches long and is made of steel wire.
It has a large eye in one end to which the short shackle is attached: a small
bushed eye in the other end, which is attached to the bomb percussion unit; and
a closely coiled section in the centre.
Shackles
The
long shackle is used to attach the bomb and parachute stabilising unit to the
strong cap of the upper V.L.A inertia link. The short shackle is used to connect
the shock absorber strop to the weak cap of the upper V.L.A inertia link.
If
the V.L.A inertia link is single acting, the long shackle is connected to the
weak cap and the short shackle connects the shock absorber strop to the strong
cap.
AD/B
No.1 Mark III Stabilising Parachute
This
contains a 9 inch (22.9 cm) parasheet with its shroud lines connected directly
to the stabiliser strop. The 9 inch parasheet takes the place of the 7 ½ inch
parachute and the cotton streamer of the stabilising parachute unit AD/B No.1
Mark II, In all other respects the units are similar.
(N.B.
A parasheet is a parachute made from one piece of fabric or from two or more
pieces laid in strips (as opposed to gores) with their warps parallel.)
Towing
Parachute
The
Towing Parachute towing parachute is used as the lower Arming unit of the bomb
and parachute arming scheme and are used as both the upper and lower arming
units in the Double Parachute Towing scheme.
Parachutes
for Bomb and parachute arming scheme.
V.L.A.
Medium Duty parachute unit.
General.
The
V.L.A Medium Duty Parachute Unit is used at the lower end of the flying wire
assembly in the Bomb and Parachute Arming scheme to pull the high explosive bomb
into the aircraft. The unit consists of a 54 inch (137 cm) diameter parachute
sealed in a metal container, a container guide assembly, cable strop and a short
shackle.
Parachute
container
The
parachute container is cylindrical in shape, approximately 9 inches (22.9 cm)
long and 3 ½ inches (8.9 cm) in diameter. Both ends are sealed. One end however
is weakly joined to the container so as to come away before the other end when
the container is pulled apart. This weak end is identified by a lug which is
located in the centre of its flat surface. The guide assembly consists of two
steel rings around the container and guides on the side of the container. The
upper ring attaches the container to the strong cap of the V.L.A. inertia link.
The lower ring has two wooden blocks that are grooved to receive the cable just
before the inertia link and hold the parachute container in place.
The
parachute is made of 1.8 ounce Rayon or cotton lawn. It is 54 inches (137
cm) in diameter. The parachute has 12 shroud lines which are brought
together and bonded to an eye, which is attached to a lug on the inside of the
weak end of the container. The length of the shroud lines from the eyes to the
periphery of the parachute is approximately 5 feet (152.4 cm). The parachute is
folded in even folds and packed in the container with the shroud lines placed on
top of the parachute in figures of eight.
d)
Attachments. A cable strop 8½ inches
long and made of 1/8 inch cable is used in attaching the weak link lid of the
parachute container to the week cap of the inertia link. The strop is threaded
the lug of the container lid, and the two eyes of the strop joined to the weak
cap of the initial link with a short shackle.
2.
Parachute
unit AD/P Mark 1.
The
parachute unit is similar indesign to the V.L.A. medium duty parachute. Except
it is of British manufacture and the parachute container doesn't have a
container guide assembly. Both the strong and weak end of the container have a
lug in the centre of the lid. A “L” near the weak end the container
identifies it from the strong end. The weak end of the container is attached the
weak cap of the inertia link with a long shackle. The strong end of the
container is attached to the strong cap of the inertia link with a 22 inch (55.9
cm) cable strop. The strop is connected using a larks head knot to the lug on
the strong end is attached to the inertia link with a short shackle. If the link
is single-acting the weak end of the container is attached to the strong cap of
the inertia link with a long shackle and the strong end of the containers is
attached to the weak cap of the inertia link with the cable strop.
Parachute
Units for Double Parachute Arming.
General.
There are two types of parachute that are in use in Double Parachute Arming.
They
are the V.L.A. Heavy Duty Parachute Units and V.L.A. Heavy Duty Lower Parachute
Units.
The
VLA Heavy Duty Parachute Units.
This
Includes a heavy duty parachute 38 inches in diameter. The parachute is
therefore smaller than the V.L.A. medium duty parachute but is constructed of
heavier material. The metal container has an attachment welded to the side of
the container nearer the strong end to which a 1 ton spring hook is attached to
connect the container to the flying cable assembly. In the centre of the weak
end of the container there is a lug large enough to accommodate a1 ton strop.
The VLA Heavy Duty Parachute Unit is used as the upper in all double parachute
arming schemes. It is also used as a lower power series of double parachute
arming scheme in all cases except when the double parachute cable cutter is
used. When used as an upper unit, the spring hook attached to the side of the
container is hooked into the lower eye of the upper cables strop and the spring
hook attached to the strap on the container is hooked in the grommet strop
between the inertia link and the swivel.
V.L.A.
Heavy Duty Lower Parachute Units.
This is
used in the lower parachute unit with a double parachute cable cutter. This
unit contains the same parachutes as the V.L.A. Heavy Duty Parachute Unit.
However, the metal parachute contains two ridges which assist in holding the
container in the basket of double parachute cable cutter.
The
container has a lug on each end. The pin in the basket of the double parachute
cable cutter passes through the lug on the lower (strong) end. The lug on the
upper (weak) end has attached to it a cable acorn strop which connects the
parachute to the flying cable.
The
acorn strop 18 inches long is made of two small cable seized together. One end
of the acorn strop is attached to the acorn. The other end is connected to the
parachute container with a pin and a cotter pin. The acorn has a hole through
its centre bevelled from both ends toward the centre. The passing of the flying
cable through the acorn permits raising and lowering the balloon without
removing the V.L.A. heavy duty lower parachute unit.
Click
Here to See 4 The Disassembly of the Bomb on Low Altitude Barage Balloons