German radar, what did they see?

[Thomatchef]

I have a small idea but to shape it I need a little bit of intel on German radar. I know a little bit how radar works but what did they actually saw on their screens? I'm especially intrested in Fyra. If they saw an airplane could they constantly track it or where their moments they didn't see them? Could they tell an airplanes speed? If an airplane turned could they see that immediatly?

I want to try to use radar in a game. For example :If the oposing force has a radar aimed on an airplane they should reveal a part of their maneuver. The speed, the direction or the actual maneuver card. The goal of the mission is to destroy the radar. The radar would have some sort of firing angle and range. These are some ideas and I hope with some extra insights I can produce some useable houserules.

71204
Tis is the fyra equipment which would be possible to make in a 1/300 model.


71203

[csadn]

Depends on the radar -- some of them could only tell how far away an object was, but not how high; others could tell altitude and direction.

Barrett Tillman's _Enterprise_ talks a bit about USN night-fighters working with _Enterprise_'s radar crews to identify holes in the radar coverage, and how to accommodate those aspects of flight the radar couldn't tell them.

Found this on the Freya-Wurzburg combo: http://www.ventnorradar.co.uk/Germ.htm . Can't find any pics of the actual screens used.

[Baldrick62]

I have a small idea but to shape it I need a little bit of intel on German radar. I know a little bit how radar works but what did they actually saw on their screens? I'm especially intrested in Fyra. If they saw an airplane could they constantly track it or where their moments they didn't see them? Could they tell an airplanes speed? If an airplane turned could they see that immediatly?

I don't know enough about the Freya-Wurzburg radar itself to give you a definitve answer however, as general observations:

a/ Most pre-1980s radar displays gave an A-scope range/strength indication on a particular azimuth bearing rather than a 'God's eye' Plan Position Indicator (PPI) view;

b/ Any rotating radar head will have an update rate, so if a radar head turns at 6 revolutions per minute (rpm), any manoeuvre which occurs in the intevening period will be unobserved - eg, it will take a minimum of at least two update sweeps to determine (on a PPI display) a true change in course or speed due to the need to compare information from each sweep;

c/ Until the late 20th century, most radars were only 2-dimensional at best, able to give range and bearing from a given point (the radar location) but not provide height, which required a separate 'nodding' antenna (or visual calculation from the likes of the Royal Observer Corps in the UK);

d/ Even when perfectly calibrated and with a near-instantaneous update rate, radar only tells you where an object was when the beam struck the object, not where it will be;

e/ The ability to accurately determine strength (aircraft numbers) is based on the search window and the radar cross-section of the object detected which, if known, is why WINDOW (chaff) was so effective in deceiving German radars about late war Allied bomber raids; and

f/ Identification Friend or Foe (IFF) is not radar as such, but a co-operative transmitter-receiver interrogator.

[phililphall]

http://en.wikipedia.org/wiki/Radar_in_World_War_II

This should give you an idea

[Baldrick62]

Illustration of an A-scope display, and others, here.

http://www.history.navy.mil/library/online/radar-15.htm

[Whiskysierra]

If you are playing with bombers against radar, keep in mind countermeasures such as 'window'(foil sheets tossed out behind the aircraft).

[wargamer]

If you are playing with bombers against radar, keep in mind countermeasures such as 'window'(foil sheets tossed out behind the aircraft).

But, even that tells the radar tech that something is coming, and the scale of the cloud on the screen will give them movement and depth (size), it doesn't just white out the scope until you actually have foil on the antenna. Also remember the phone system was working when the allied ground forces moved into france and Germany. This allows for a lot of ground spotters to report to a central air defense system. Murphy requires that you have to provide the enemy is always more prepared than you want him to be.

[Whiskysierra]

The way I would play it might be to incorporate d6 rolls so, off shore under 5 gets you a vague blob, no alt. As spotters come in 3 or higher gets you 2 out of 3 of alt, numbers and bearing. Once you reach double ruler distance you have the full story.

[wargamer]

Double ruler range, unless you are both in clouds is plain visibility. Dropping bombs from 20,000 feet, means you missed.