OT:decoding enigma (was Re: One of only 3 "enigma machine" stolen;

----- Original Message ----- From: "Sean 'Captain Napalm' Conner" <spc(a)armigeron.com> To: <classiccmp(a)classiccmp.org> Sent: Wednesday, April 05, 2000 3:02 PM Subject: Re: OT:decoding enigma (was Re: One of only 3 "enigma machine" stolen; a Heard of it, haven't read it. Must see if I can round up a copy. of the isn't to Sometimes, perhaps, but I must differ with you on that point. Early in the war, it was remarked that the side with the best photographic intelligence would win. The British (somewhat reluctantly at first) developed the essentially WW1 cameras and aircraft into an excellent system, not only of obtaining good quality pictures, but performing a careful and detailed analysis of them. Much of what was known about Peenemunde and the V1/V2 projects that emanated from it was gleaned from Photo reconaissance, with hints from Ultra at times. Numerous other examples, (the finding of the Tirpitz for instance) also were a direct result of PR. German radar was first identified in a photo taken (using a hint from an intercepted Enigma message) which ultimately resulted in a low-level (PR pilots referred to it as 'dicing') run past a "Freya" on the French coast. Later PR work found the installation at Bruneval that was subsequently raided, and parts and staff captured, by a small force of British commandos. Models of the site and it's approaches were built up using extensive PR 'cover' of the area. It's probably fair to say that the 2 had a symbiotic relationship, PR being used to confirm, expand or capitalise on the Ultra intelligence. It's known that the Chief Scientific Advisor to Winston Churchill considered it impossible for anything like the V2 to be built, as the weight of the vehicle strong enough to contain sufficient cordite would exceed it's lifting ability. (This is before liquid fuelled rockets were considered practical on a large scale). Despite 'Ultra" traffic to the contrary, his stand was overturned with the help of PR cover of Peenemunde presenting visible evidence, on top of Ultra traffic, sufficient to convince Churchill. Had this not occured, it is possible the German development and deployment program would have been significantly unhindered, which could have had serious consequences for the Allies. The successful detection and prosecution of the V1 'Ski sites' in France was almost entirely a result of PR interpreters noting the construction of the buildings and lauching ramps, which in the first stage, were quite large and served by a rail spur. Destruction by bombing of the large scale ski sites led the Germans to construct a smaller, less conspicuous site, with only a couple of essential structures. These too were found, though not all were destroyed. "For want of a nail......" The British pioneered the practice of using a single high performance fighter, stripped of guns and other additional weight and drag adding items, painted so as to make it hard to see against the sky. Such an aircraft could outrun enemy fighters, and was able to operate (and take useable pictures!) well above the accurate range of AAA of the time. High altitude presented it's own problems, and required such things as ducting warm air over the cameras and lenses to stop them freezing or frosting over in the subzero temperatures. TheGermans began to adopt similar techniques later in the war, (the Arado jet bomber was used for PR at one time). The German's had a somewhat fanciful notion of the excellence of British Intelligence, (it was good, but not THAT good) and put down some seemingly 'clairvoyant' actions by the enemy to spies and other 'conventional' sources of information. They apparently did not at anytime suspect that Enigma had been penetrated. (Though I believe the question was asked of the Intelligence service at one time.) Considering the security wrapped around BP and it's "Ultra" traffic, this is not surprising. ON TOPIC BIT: :^) The existence of the Colossus machine (used to penetrate the Geheimschreiber codes) was still secret for many years after WW2. The first true computer, it predated the Eniac and other things by some years, but it's existence was so shrouded in secrecy, it was over 30 years before it became public knowledge. A working replica has recently been created at Bletchley, and fairly recently, the plans for the Bombe decoding machines used to penetrate Enigma, (none survived the war, and the plans were thought to be lost)were discovered in records of the British Tabulating Machine Company who built them under highly secret conditions for BP. An attempt is now being made to construct a replica of the Bombe. (I'm probably preaching to the knowledgeable here, excuse me if you know this already) END OF ON TOPIC BIT... For 'might' read 'will'. If a code is suspected of being compromised, or even if a code or cypher book is lost (in the conventional sense) it is invariably changed. The author of the book that contained the reference to the U-boat incident remarked that it was probably fortunate the U-boat sank under tow, (during the night IIRC) or it might well have been spotted by a German aircraft, and the codes would doubtless have been considered compromised and changed at once. No combatant would risk using a compromised code. Exception: If you know your code is compromised, but the enemy don't know that you know, it can be useful for disinformation purposes. Example: German agents were dropped into Britain. As far as is known, they were all captured before they could send any useful information. (One broke his leg in the parachute landing, and woke up in an English hospital) The spies were given the option of death by firing squad, or incarceration in a prison. The incarceration option was conditional on thier sending information, in their own codes, as directed by their captors. The V1 attacks on London were actually affected by this, as the spies were directed to inform their masters that the weapons were overflying London and impacting beyond it. This caused the Germans to alter the autopilot settings on the V1's so that many that might have hit the city fell well short into (mostly) uninhabited territory. Cheers Geoff Roberts Computer Systems Manager Saint Mark's College Port Pirie, South Australia geoffrob(a)stmarks.pp.catholic.edu.au netcafe(a)pirie.mtx.net.au ICQ: 1970476