Turbojet powered cruise missiles

Vacuum tube technology reached a very high level just prior to WW2 and in particular during it. Automated mass produced Vacuum tubes between the size of a mans thumb and a ladies pinkie became standard devices. Some were highly economical; having pressed glass bases through which the conductors passed. They were reliable too 50,000 hours was not uncommon in a specified on/off cycle. Other's had steel housings and could handle a great deal of vibration. Steel envelop tubes were used for the analogue computer autopilot on the V2 because of their toughness. The reason a electronic computer had to be used was both the great speed of the electronics but the vibration resistance which disrupted mechanical computing devices. There were of course highly specialised micro tubes that handled the acceleration of a gun launch that were fitted into artillery ammunition.

Certain specialised tubes, such as those generating high output powers for radars had shorter lives.

There were very few advances after WW2 and most of those were in specialised areas.
1 Video Recording Tubes became more light sensitive with Videocon taking over from ikonoscopes.
2 Besides Magnetrons high power Klystrons and Travelling Wave Tubes allowed sophisticated microwave radar and overcame the limitations of magnetrons.

Vacuum tubes developed only slightly: by identifying chromium contamination in the tungsten filaments of vacuum tubes the computers that operated the NORAAD and SAGE (Semi Automatic Ground Environment) achieved 500,000 hour life which gave the reliability to allow digital computers for dispatching F101 and F106 to intercept possibly threatening nuclear carrying bombers.

Printed Circuit Boards were used by both sides, the Germans used ceramic ones. Ideas such as terminal blocks came in.

These advances were not necessary for the kinds of tubes required for automatic control of a missile.

The relatively reliable miniature vacuum tubes made many more devices practical. It was more up to engineers to come up with a conceptual frame work for creating circuits and circuit building blocks and to realise those.

German aircraft in 1940 could carry radar altimeters, blind approach systems (FuBL) and fully automatic landings had been carried out. Auto track radar came in both German and US radar in 1943.

And the guidance system as used in the Mistel aircraft simply didn't work. They struggled to hit a cliff face in early testing, and were no better when used operationally. They, or rather the warheads, were not designed specifically for use against dams either. Operational attempts were made on a variety of targets including dams and ships with precisely zero success, unless you count the near miss on HMS Nith. She may not even have been the intended target!

'Eisenhammer' never happened and other attempts against various Soviet targets on the Eastern front were as unsuccessful as those against the Allied bridgehead and Mulberry harbours in Normandy.

You are talking up a system which might look good on paper, but forced prematurely into operation,as were many late war German developments, it proved a very expensive failure.

Cheers

Steve

With one plane and one bomb, very precise accuracy would be required. The technology did not exist in WW2, except possibly remote control TV guided weapons. None of other systems would have provided the accuracy. Rf guidance was susceptible to countermeasures, and the Brits were good at it. Inertial nav capability was no where near good enough. In the 70s INSs drifted at a mile an hour. If any beam system would have worked, they would have been used in Vietnam and many crew could have been saved, but, they weren't. The TV remote guided Bullpup was marginally effective, but not until TV guided and laser guided weapon became available did one bomb one hit became possible and even then spotter aircraft was needed. In the 1980s, the B-2 was tasked with very precise autonomous dumb bomb drops (yes even nuclear bombs sometimes need to be precisely delivered). In order to achieve this accuracy, a highly precise INS system actively updated by a stellar inertial system and a high resolution radar update capability was required. None of these systems existed prior to the 80s, much less WW2. The Germans were never going to have a precise V-1 system. Now if they had cancelled the He 177 and built another 9000 V-1s, this would certainly have shaken up Britain and occupied a lot of military defense. Still wouldh't have changed the war.

Another thought that hasn't come up is using animals onboard for guidance, like American researchers did with trained pigeons targeting specific target shapes/patterns on the horizon. It worked for shipping, so possibly could work for cities as well?

Probably something pulse jets would prevent due to noise and vibration. Turbojets, ramjets, and rockets would work, though.

For that matter, I wonder if that would work for anti aircraft missiles, with birds trained to target bomber formations.