Mendip Starfish Sites

These sites have been on DP before, however, I found myself in Somerset over the weekend and decided to have a quick visit. The sites are located in the Mendip Hills.

Brief history - these sites were built during the war to act as decoys to lure the Luftwaffe away from major cities and military installations. The sites posted here were designed to decoy bombers away from Bristol. The decoys were known collectively as Starfish and used water and creosote to simulate incendiary bombs exploding. In addition glow boxes were also installed at the site to simulate street lighting and railways etc. These glow boxes were powered by electricity generated by generator sets housed within the control buildings shown in this post. The idea was that the Luftwaffe would bomb the simulated fires and lighting as opposed to the real thing. Whether it worked here or not is open to debate.

General external view

Entrance protected by blast wall

View from roof looking down at blast wall

Bases for Coventry Climax petrol generator sets

Air inlet for petrol engines or cable ducts ?

Being where this place is located high in the Mendips this stove base would have been well
and truly needed

Concrete reinforcement showing through in the roof slab

The doorways between the generator room and control room

These pipes were probably used to provide cooloing water to the petrol engines

Control room view

View towards escape hatch in control room

View down escape hatch from roof

This is the second site located near Cheddar

Entrance showing concrete roof slab

Exhaust port

Looking up escape hatch


Thanks for looking

Great to see these sites again. Fascinating subject and I keep meaning to actually buy the book 'Fields of Deception', instead of having to order it from the library.

nice one not seen these ones before, but i am sure we have a site near swindon, out in the hills with similar functuions, will have to get up and have a look some time

Interestingly there has been more research on the black down site in the last few years.
New evidence now points to the site being initialy and anti invasion obstacle. The small bumps on top of black down are now thought to of been supports for anti glider defences.

Tho it still seems the site was later used as a false Bristol startfish site.

Soome details here:
http://webapp1.somerset.gov.uk/her/details.asp?prn=24114

I believe this is in a slightly different place to the anti-glider stuff and is definitely a starfish site. Please don't tell me you missed the awesome z-rocket launcher bases in the field next to it though!?

There is another generator set actually on black down but it's gated, along with a buried oil tank on the side of the hill.

(I have contributed extensively towards the info on the Somerset HER )

krela said:

I believe this is in a slightly different place to the anti-glider stuff and is definitely a starfish site. Please don't tell me you missed the awesome z-rocket launcher bases in the field next to it though!?

There is another generator set actually on black down but it's gated, along with a buried oil tank on the side of the hill.

(I have contributed extensively towards the info on the Somerset HER )

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You got me bang to rights I did miss the rocket launcher bases. I only knew they were there after I had returned from the site and looked at the post on DP. I know poor planning Will have to try harder in future.

hydealfred said:

You got me bang to rights I did miss the rocket launcher bases. I only knew they were there after I had returned from the site and looked at the post on DP. I know poor planning Will have to try harder in future.

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Oh I wasn't making a l337 you suck type comment, I'm gutted for you cos they are awesome. =/

krela said:

Oh I wasn't making a l337 you suck type comment, I'm gutted for you cos they are awesome. =/

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No I didn't take it that way - I'm just kicking myself for not finding the site - still the area is one of my all time favourite walking spots so will be going back. The views up there are stunning.

krela said:

I believe this is in a slightly different place to the anti-glider stuff and is definitely a starfish site. Please don't tell me you missed the awesome z-rocket launcher bases in the field next to it though!?

There is another generator set actually on black down but it's gated, along with a buried oil tank on the side of the hill.

(I have contributed extensively towards the info on the Somerset HER )

Click to expand...

Ah, didnt realise that, doh!

One of my friends is an archeologist who had some involvement with it, maybe you've crossed paths..

Sweet stuff HDF

I'll be adding the decoy sites listed in Fields of Deception to the next version of the overlay in a few days, so you can all go and find your local site and see if the control bunker survives.

This looks like an interesting site.
where a hell of alot of work went in for a decoy site .

SK

Actually not a massive amount of work. The only permanent structure was the control bunker. Most SF sites were ready in weeks once a site was found. They could be recharged in a day if lit and it took between 8 and 12 men to do that with just two to man them overnight. Considering the hundreds of bombs they attracted they were a fantastically cost effective measure in terms of both men and supplies.

I thought the they were not very effective due to the use of radio triangulation by German bombers?

penance said:

I thought the they were not very effective due to the use of radio triangulation by German bombers?

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Both Knickebein and X-Gerat could be jammed but X-Gerat wasn't jammed effectively until later in the war. X-Gerat was only used by the pathfinders like Kgr100 to drop target marking incendiaries, the following bombers dropped on the incendiary markers or fires. It was these folowing bombers carrying the HE that the decoys were meant to fool. Overall the decoys attracted approximately 2200 tonnes of HE bombs, this is though to be a conservative estimate due to the tight radius within which a bomb had to fall to be judged as an attack. Often the decoy crews wouldn't know they had been attacked at all such was the innacuracy of the bombing.

Gotya, thanks for that. Interesting answer

I was always lead to understand that the boffins had developed a system for bending the knickebein beam slightly to the left or right.The bomber flying along the beam would veer slightly one way or another and be led in the direction of the starfish sites.I know this is a great simplification of the system as the sites were also linked to ROC posts and the gun defended area command posts and worked as part of a combined ops team.

That's correct, the beam could be deflected or jammed but I'm not sure they had the capability to control it with any reliability. What they did know due to the cracking of Luftwaffe Enigma is where the raids were likely to come and on a few occasions, specifically in the case of Coventry, Starfish were lit in anticipation of a raid which actualy was altered to Southampton in the event.

Interesting article about Coventry in this months britain at war mag..