Parachute-and-Cable (British Anti-Aircraft Weapon c. 1940).

[Wingknut]

Hi folks,
Maybe this should be under 'Missile Projects' (or indeed 'Army Projects') - if so, let me know and I'll shift it, but anyway here are some details and images relating to Britain's 'Parachute-and-Cable' ground-launched anti-aircraft system.
Cheers, 'Wingknut'

“PAC (Parachute and Cable) launchers – a highly unusual anti-aircraft weapon which … consisted of a small rocket trailing a steel cable, which shot vertically 300-400ft into the air and then descended on parachute. The rockets were grouped in batteries of nine, to be launched simultaneously in a curtain pattern. The idea was that of creating a web of steel cables across the path of a low-flying aircraft, causing it to catch the wires and stall to the ground.

The parachute had a dual function. Once the rocket burned out, the canopy slowed the cable’s fall, allowing the “curtain” to stay up in the air for a longer time. Secondly, if the cable caught a bomber’s wing, the added drag from the parachute was hoped to be sufficient to foul its flight. There was also a smaller parachute at the lower end of the cable designed to balance the drag of the first one and thus prevent the cable from it from sliding off the wing of the aircraft. Later versions had an additional explosive charge hung at the bottom of the cable, intended to detonate on contact with the aircraft.”
Text from: http://spitfiresite.com/2010/08/battle-of-britain-1940-kenley-raid-parachute-cable.html

Photographs from: https://ww2aircraft.net/forum/threads/wire-net-trailing-aa-rockets.2744/

Text-image (‘Box 3’): page 14 of Britain's Air Defences 1939-45 by Alfred Price, found here: http://www.scale-models.co.uk/threads/barrage-balloons.10160/

See also Popular Mechanics Magazine, January 1943:
Cover from: http://www.ebay.com/itm/POPULAR-MECHANICS-MAGAZINE-Jan-1943-Uncle-Sams-Warbirds-/262119262706

Page 6 extract from Google Books:
https://books.google.co.uk/books?id=htYDAAAAMBAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=snippet&q=rocket&f=false

 

[Jemiba]

Had a look into an old paperback from Heyne publishing "Geheimwaffen der Alliierten" (Secret Weapons of the Allies),
1976, where such systems are mentioned, too. There were several types, for example the Type L, based on a
50,8 mm rocket, towing a cable of 182 m with an attached mine up to a height of 305 m.
The Type K was a 76,2 mm rocket carrying two small parachutes and a mine connected by a cablem which were released
at a height of 6000 m.
(Not actually a missile, but at least the Type K was a much more sophisticated weapon, than just an unguided rocket)

 

[Brickmuppet]

Aside from the basic concept, is there any indication this was related to the RN's UP AAA rockets? That is, were they from the same design team or largely seperate?

 

[Jemiba]

In the mentioned paperback it is said, that the Admiralty regarded this concept as quite good,
but too complicated and expensive, so that they decided to switch over to the simpler and
cheaper UP unguided rockets.

 

[Wingknut]

I think one related system was maybe the 'drogue parachute' device:
"Once struck by a plane the drogue parachute would open and the bomb would release from the balloon. As the plane flew on the bomb would be drawn over the top of the wing and detonate", http://www.bbrclub.org/free_balloon_operations_in_world.htm
Amongst other things, the site above also contains details of 'Operation Outward', which seems to have been Britain's (cruder) equivalent of Japan's fu-go free-balloon bombs but they may get a thread to themselves.
Thanks, 'Wingknut'

 

[Grzesio]

The rocket in the 2nd picture actually is a German one, known as the 15 cm Kz 1000 (Kp). It carried some 900 m long rope fixed to the ground at one end, the other end was fitted with a parachute.

 

[Bob Sackett]

Any mention anywhere of dimensions of the parachute or cables? I work in a small Royal Canadian Navy museum and we've just had a trunk of items donated that belonged to a gunner who served during the war. Found a smallish (6' diameter) parachute with a 5' steel cable attached, stamped with a 1940 date. Chances are very slim, I know, but could this be a PAC?

 

[cardonet]

Here is some information about the Passet system, proposed in 1917 and 1920, without success.

 

[Bob Sackett]

Here is some information about the Passet system, proposed in 1917 and 1920, without success.

Oh well, what i found is NOT one of these. Thanks very much for the information.

 

[Nik]

Were the wire/chute whatsits specifically intended as airfield defenses against Stukas ?? They'd wrought such havoc in France, would have caused similar problems if they did get past the RAF fighters...

Here in NW UK, an uncle who did fire-watch on river-side roof of Liverpool's Anglican cathedral once mentioned that the line of barrage balloons along the crest of high ridge behind the city centre seriously dissuaded low-flying...

I'm also reminded that some of the London & SE barrage balloons that 'escaped' their moorings in strong winds ended up dragging their cables across Europe, to the detriment of phone and power lines...

Post iteratively sub-edited by duty cat, who is now chasing cursor across this page...

 

[iverson]

I think that part of the reason for these weapons was that they could be produced quickly, cheaply, and in large numbers with little dedicated tooling. Production of guns required specialized tooling and experience, and manufacturers with both were already strained to the limit. Rocket weapons also did not require the hefty supporting structure that an antiaircraft gun required, something that made immediate installation of the UP aboard RN ships possible. Once mass-produced Oerlikon and Bofors guns became available in numbers, demand for these rocket-and-cable solutions disappeared.

The cable was simply a way of increasing the effective radius of an unguided, fairly inaccurate weapon. It was essentially a low-tech stand-in for a proximity fuse.

 

[Nik]

I think that part of the reason for these weapons was that they could be produced quickly, cheaply, and in large numbers with little dedicated tooling. Production of guns required specialized tooling and experience, and manufacturers with both were already strained to the limit. Rocket weapons also did not require the hefty supporting structure that an antiaircraft gun required, something that made immediate installation of the UP aboard RN ships possible. Once mass-produced Oerlikon and Bofors guns became available in numbers, demand for these rocket-and-cable solutions disappeared.

The cable was simply a way of increasing the effective radius of an unguided, fairly inaccurate weapon. It was essentially a low-tech stand-in for a proximity fuse.

Also, it might have both a positive effect on UK morale plus, like barrage balloons and anti-parachute / anti-glider fences, offered serious discouragement of such attack modes...
Probably out of all proportion to effectiveness but, hey, just knowing it exists would, um, focus air-crews' minds some-what, given it's a long, lonnng way home with a cropped wing...

 

[DenisBRETEAU]

Any mention anywhere of dimensions of the parachute or cables? I work in a small Royal Canadian Navy museum and we've just had a trunk of items donated that belonged to a gunner who served during the war. Found a smallish (6' diameter) parachute with a 5' steel cable attached, stamped with a 1940 date. Chances are very slim, I know, but could this be a PAC?

Bonjour Bob
Je pense qu'il y a une bonne chance que ton parachute de 6' provienne bien d'un système d'A.AD Type L effectivement.

 

[kocovgoce]

so even today it can be used if they had a small radar which, when a plane passes over it, will activate the rocket to fly in front of the plane and drag a cable or net or simply if they had a small cable through which information will be transmitted to the rocket which will explode at the height of the plane.

 

[riggerrob]

What if they installed a second, slow-burning rocket motor to make the contraption “hover” over the defenders?
Adding a few minutes of loiter time would discourage a second wave of attackers.

 

[iverson]

What if they installed a second, slow-burning rocket motor to make the contraption “hover” over the defenders?
Adding a few minutes of loiter time would discourage a second wave of attackers.

Well, the Royal Navy achieved the same thing, more or less, with the parachutes used on 7-in Unrotated Projectiles (UP rockets). A barrage of UPs was supposed to lay an airborne minefield in front of attackers. The parachutes were supposed to hold the mines up until the approaching planes encountered the wires. At that point, it was hoped that the drag from the parachute would winch up a small explosive charge, also attached to the wire, destroying the enemy aircraft.

Tests on HMS Hood didn't go at all well. But the things were nonetheless installed on lots of ships until 2-pounder pom-pom mounts became available.

THe UP was the personal project of Churchill's son-in-law, Duncan Sandys, of 1957 Defense White Paper fame.

See:

https://en.wikipedia.org/wiki/Unrotated_Projectile

http://www.navweaps.com/Weapons/WNBR_UP.php

 

[kocovgoce]

one of the problems with the missiles was that Nazi planes could spot them and get away but also the steel wire from rocket to fall on a transmission line and make a short circuit to turn off the transformer assembly