I have mixed feelings, the space programme achieved great things but the V1 and V2 were terror weapons.
The V2 (and V1) were used as terror weapons but that's not how von Braun, his engineers or
German Army or Luftwaffe intended it and it was not likely what would have continued long term as new guidance systems came in. Werner von Braun promised from the beginning 1 mil accuracy, which would be 300 meters. It was well possible and the people such as the radio control electrical engineer Helmut Holzer were hired before the war. These systems barely missed introduction into service.
Von Braun probably no more than Roy Chadwick (designer of the Lancaster) wanted his aircraft to be
used for "dehousing", "area bombardment" and "demoralisation" which is terror bombing and
carpet bombing of civilians by a euphemism used in the Area Bombardment directive that caused
70,000 casualties in Hamburg and destroyed 90% of some cities.
Not targeting innocent life is deeply embedded in our morality and the loss of every life is a tragedy
for our civilisation and people. I'm reminded of the Ju 88 night fighter crew that defected their
aircraft when they were ordered to shoot down a civilian BOAC registered Mosquito flying from neutral
Sweden.
Nevertheless at each stage of the war the each side exaggerated and demonised the other so it
could justify its own strategies and escalations. The Germans were not the worst at this.
When von Braun took on the development of what would become the V2 (officially called A4) he
promised to provide 1 mil accuracy, roughly 1 meter error per 1000m range. It was a figure plucked
out of the air because long range artillery could provide 2 mil. The V2 at 350km range should thus
provide 350m accuracy.
The V2 ended up being used about ½ to 1 year early before the three guidance systems that could
achieve this were completed.
The V stood for Vergultungs or "Reprisal" and the idea was not pure revenge but to inflict the same
terror the allied bombardment campaign had on Germany so as to force the allies to negotiate a
stop. The kind of practical accuracy exhibited by the strategic bombing campaign I think is well understood.
For the record the three guidance packages were:
1 "Vollzirkel" in which the A4/V2 rode a circular scanned beam during its 70 second boost phase.
Position of the A4/V2 could thus be tightly controlled and electronics would damp out any sideways
drifting velocities. Doppler would measure the speed accurately and a radar transponder distance
for a complete cut off equation.
It probably would have achieved its 350m accuracy; the target did become 500m. One could expect
a degradation of a few hundred meters during re-entry due to cross winds so this was likely optimistic. Voltzirkel had undergone years of development using frequencies of 50cm, 27cm and finally 9cm to eliminate the problem of ground plane interference. It did get built
and tested.
2 "SG-66" was a more advanced gyroscopic guidance than LEV-3 A4/V2 guidance system. The V2
tilted over to 48 degrees and an accelerometer shut of the engine when the speed had been
achieved. SG-66 added an accelerometer to control sideways drift and used better gyros that were
more easy to control because they were gimaballed. Its accuracy was expected to be the same as
"vollzirkel". SG-66 was built and undertook several flights.
3 The basic V2 had already begun using a basic beam riding system called Hawaii that controlled
only in the horizontal plane that pulled in the error about 50% in cross range that when used with
doppler cut range error 10%. Germans own measurements for LEV-3 showed 4.5km error at maximum range. If the doublecross effect of British counterespionage is factored out they achieved 6km. Some of the errors are probably guidance failures rather than system limitations. There were a number of optical and radar based tracking systems to measure impact point but they were either not believed or not ready.
The Winged A4b was not only designed to extend range by gliding but was designed to be guided to
within 120m during re-entry to its impact point. The guidance system was called "Wasserspeigel"
and used a trio of Wasserman radars layer on their side to get 0.01 degree accuracy and a Erstling
Transponder for range. If jamming was implemented, it was supposed to become a mid course
guidance system that had its position updated half way and continue under control of its SG-66 like
inertial guidance system with the accelerometers keeping track of range.
Likewise with the V1. It already had a primitive tracking system called Ewald that was supposed to
modify subsequent launches on the basis of prevailing wind.
The Ewald-II system implemented full remote control in which the V1 would emit a single pulse at a
predetermined time and place. This was received by 3 ground stations which used the differences to
calculate position. It was meant to be jam proof since there was no interrogating pulse that could be
spoofed. A course correction was then sent via impulse modulation and decoded on a endless tape.
This was supposed to get error down to 2km if applied as a midcourse system. This was also
designed for the BV-246 glide bomb.
The V1 was also to receive the Porsche 109-005 turbojet, this would eliminate the vibration problem
that effected the guidance of the V1.
Several terminal homing systems were also designed for the V1 such as the radar homing Radischen head tested on the BV246 glide bomb