Kretchmer waves

I arranged for the funny stuff, but not the holes, to be transported.

StoryKettle » QUAINT » Kretchmer waves

Copyright © 2020, Michael M Wayman

It was Thursday afternoon when I received a strange phone call from the county chief constable: “There are strange goings-on at a farm near Clacton.”

“Drop everything!” I got my team together. “We’re off to Clacton.” It wasn’t easy to find, there was a uniformed policeman waiting to show us around.

“There was this old man here, I think he was a foreigner, didn’t talk much, didn’t do any farming. The place is rundown, he’s gone now. But there are these very big round holes in the walls of the outbuildings and all those funny, big bits of brass in one room. All very odd.”

We examined the holes, they were perfectly round. We examined the rooms, one room contained funny, big bits of brass and notebooks of funny ideas. I arranged for the funny stuff, but not the holes, to be transported to a disused factory in Reading.

“Thank you officer for showing us around. And if you see anyone on the farm report to your chief constable directly, he’ll know what to do.”


Back in the office I contacted three old friends of mine, all professors in science and engineering. Did they want to help the war effort? Yes, they did. Did they want to spend a few months in a disused factory investigating a possible new field of science? Yes, they did.


Three months later found me in my boss’s office, I had brought him two reports.

The one from the scientists was negative: they could find any new science in the big bits of brass and the notebooks and no old science either. They had tried to follow the notes to build a super weapon that could make big round holes in things, but without success. They made a few suggestions for the future, however they were leaving the country for a new, very interesting project, I think it was the Manhattan project.

The second report was also negative, a police forensic team had taken the farm near Clacton apart. No bodies, no blood, but a machine that was driven by a two‑stroke motor that could be bolted onto a wall and could cut a large round hole in the wall by going round and round for several days. They also found a small hill made of round pieces of wall and covered with soil.

“So that’s it, then? There is no super weapon, so end of project.”

“Yes and no, boss. Yes, there is no super weapon, it was actually a hoax. No, the project can continue. Here’s my plan...”


I opened an office in Haslemere, I employed two local girls as typists and a staff officer was seconded from Northampton: Jean, Margaret and Mr Underwright. The office was the Control and Communication Centre for Project Undertow, code-named white office. The red office was the research unit in Reading, the green office was the operational unit adjacent to the Scampton Airfield north of Lincoln and the very secret black office.

I was the official liaison and coordination officer for the project, I collected the reports and had them typed, archived and distributed. It was part of my job to visit each office weekly, this being rather difficult as the red office and the green office and the black office did not exist.

The Project Undertow existed only in my head and in the heads of a few people in a distant land.


Roddy was code-named green4 and was a very technical type. He always wrote in blunt pencil, drawings too. An early report:

We have had some success with a two foot cube of brass (50% copper and 50% zinc), a ten gallon container (of 50% test octane and 50% isopropanol) and two magnetron transmitters, one on each side (see diagram 7/1). It created a hole in the ground.

We need to experiment with the brass alloy, the transmitter frequencies and the interspacing of the parts. A new idea is to place everything on a big trolley and push the trolley around and perhaps create a trough in the ground.


Ben was a higher officer, but no longer flying as he was over thirty, who wrote with a green ink fountain pen; he was code-named green7. Another early report:

The idea is to create a weapon that A) works and B) will fit in an existing aeroplane, for example a Lancaster bomber. It is not important if the weapon creates holes or trenches, large or small; important is the rate of volume destruction.


Professor Dorkings wrote pages of highly scientific theory which I copied at random out of the most complicated books I could find in a university library. He was code-named red9. I won’t bother you with a sample of what he wrote. Once in a while we got a stern message from black99.


After I had written a report, mostly from green4 and green7, I gave the report to Mr Underwright (white3) who instructed the girls to type the report with at least three carbon copies. They really had fun with red9, all those funny Greek letters and superscripts and subscripts which had to be done by hand. And green4’s spelling and grammar had to be corrected.

I took one copy of everything to the black office and the other copies went into the archive. Apart from the one copy of everything that Mr Underwright took by train once a week on Saturdays to Brookwood Cemetery and left in a so-called dead letterbox. This was emptied weekly by an employee of the embassy of a neutral country.

Somehow the information found its way to the enemy, just as we wanted. My boss showed me an enemy intercept (probably from Bletchley Park) containing a report from green4, fantasies written by me. We both had to laugh.

The plan was obvious: to dupe the enemy into setting up a large project similar to our own especially with lots of inflammable fluids, very hot magnetrons and a few bomber aircraft.


A wonderful idea: green4 made a great discovery with which you could sense the special waves, the so-called Kretchmer waves, coming out of the brass block. All you needed was an ordinary four‑valve radio receiver and a lot of octane. It was very dangerous, seven people had already been burnt to death. You could detect the waves from the brass part.

You could detect the Kretchmer waves from anywhere and that was a problem for green4:

The Kretchmer waves made funny noises on the radio when the brass block was correctly activated (the right amount of octane and the right magnetrons) and stopped when the magnetrons were switched off (or as usually happened, when everything burst into flames). However sometimes we heard the funny noises when everything else was switched off, but much weaker. What was it?

Had the enemy been experimenting? Had they made Kretchmer waves? Probably. I set up three new direction-finding stations, orange office in Kent, purple office in Cornwall and pink office in Northumberland. Needless to say, all three of them were a figment of my imagination.

They had a lot of fires, eventually they identified two sources of Kretchmer waves, near Lincoln and at Malmsheim near Stuttgart.

My boss and me knew from the intercepts that the enemy had started experimenting at the Malmsheim Airfield. Won’t the enemy be pleased that we have detected the Kretchmer waves that they have generated.


Jean didn’t like Mr Underwright, he had made advances on her and on Margaret too. “And she’s married.” I told her there was something not quite right about Mr Underwright and that she should watch him.


We knew that the enemy was having problems with their Kretchmer wave detector because Mr Underwright asked several times for more details of our detector “for the archive of course”. I decided that green4’s reports would contain much detail about our detector, useless detail. That evening at home I unplugged my radio, removed some screws and the cover and looked at it. It was what the enemy called a Volksempfänger:

We are currently using Utility four‑valve radio receivers, pretty simple and cheap, about £12 each. The direction-finding stations use them too. The valve line‑up is ECH85, EF39, EL33 and BVA216. Only the medium waveband is covered.

The funny noises that are heard when Kretchmer waves are detected are individual screeches that begin quietly and get louder and louder and then restart. You can’t mistake them.

The trick to detect Kretchmer waves is to pour large amounts of octane or ordinary petrol over the hot valves in the radio.

That last report was hot enough to burn the house down.


It got more exciting and more dangerous. Reports from green7:

We’ve finally got a prototype, we have named it Punch, that makes holes, big holes in everything. It’s mounted on a big trailer which we haul around the woods making big holes in the ground and in trees and in deserted buildings.

Punch Mk3 has been fitted into the bomb bay of an old Lancaster bomber and tomorrow it’s going to fly.

Then no reports for six weeks, big secrecy clamp-down. Mr Underwright was unhappy. Margaret got another job. I took Jean for a walking holiday across the North Downs.


Disaster happened, a report from green7:

The test went fine, the Lancaster flew repeatedly over the test field destroying this, that and the other. But suddenly it burst into flames. The three-man crew and the four technicians, including green4, perished.

It was back to the drawing board again.


The problem was not the large tanks of octane and isopropanol. No, it was the large block of brass. It had moved about and thrown the Lancaster violently to one side and crashed it. Reports from green7:

Apart from the appalling crash the test run was very successful. The damage created by the Kretchmer waves was much greater than expected. There was also an unforeseen bonus: the soil, the trees, the pieces of wall etc. that had disappeared reappeared somewhere at random up to 500 metres away. A road was blocked for several hours with pieces of tree. We call this the reappearance effect.

We have made several discoveries, the expensive test octane and isopropanol was not needed, ordinary petrol (octane rating 100) could be used, which was of course what the Lancaster used. The petrol in the vast wing tanks had increased the effectiveness of the test run.

In fact we could store petrol in the Lancaster bomb bay to generate electricity for the magnetrons, to increase the Kretchmer waves and use the same petrol to power the Lancaster on long return flights.


An officer asked to see me in the office in Haslemere. “You are the official liaison and coordination officer for a certain project and you may have an interest in certain enemy airfield.”

“Possibly!” No names, no pack drill.

He showed me a very large, aerial photo of an airfield, it was Malmsheim. “You can see an airfield, I can see a lot more. Now look at this.”

He showed me a second photo. “Look here, these are huts that were not there in the first photo. This huge black area is also new. It is fire damage, caused by burning fuel, lots of fuel. And before you ask, it is not near any fuel dump and it is not near the runway. There are also the wrecks of possibly twenty Junkers Ju 88 aircraft. What ever you’re doing, keep doing it. A really good show, sir!”

He shook my hand and left.

A week later the direction-finding stations reported a lost of signal from Malmsheim.


Good news from green office:

Another discovery: the brass block should be able to move around a bit (up to a metre in the horizontal plane. This is a big problem, the block is very large and heavy. It was the violent movements of this block that caused the accident.

We are working on Punch Mk7: six magnetrons, two petrol-powered generators, six very large tanks of petrol, and a newly designed big brass block mounted on a moving platform. The biggest change is however the brass block, it’s even bigger, but it’s HOLLOW.

After many successful field tests we are going to do a Lancaster test soon.
WISH US LUCK!


Intelligence informed us about the Bad Zwischenahn Airfield near Bremen. The direction-finding stations duly reported strong signals from Scampton, weak signals from Bad Zwischenahn and no signal from Malmsheim. This was to be the last report that Mr Underwright would deliver to the enemy.

Big problem! Punch Mk7 would soon be ready for operations and cause great damage to the enemy. That’s if you believed the reports. I wrote all the reports, I knew that Punch Mk7 was the figment of my imagination. My boss and I agreed to stop the reports and leave the enemy in the dark. I arranged for Mr Underwright to be arrested in Brookwood Cemetery on the next Saturday, he was probably shot.

There were just the two of us left in the office. I explained to Jean that the project was finished. She just laughed.

“I knew that the project was all make-believe. I saw you in your office writing with a blunt pencil or a green pen. I...”

“Will you marry me?”

“Yes!”