Nightfigher's designer has stated that:
The search and sweep radar counters are not intended to recreate actual searches of sectors of sky, as if you were training radar beams on particular portions of the map. The game mechanic does not map to real-world procedures.
Radar in this era was an inexact tool, and so what I've tried to capture in the mechanic is some of the black art of assembling an air picture from fuzzy information provided by radar. This is very much design for flavour. It is not historical.
This variant strives for a closer approximation to what Freya and Würzburg radar actually provided the nightfigher and the zone controller (Jägerleitoffizier).
1. Search and Sweep counters are not used.
2. Freya is long-range, early-warning radar. It is the source of pre-scenario intel which is provided to the player: raid size (massive or normal), component (main force or stragglers), and bias (red or yellow).
Freya provides no other information to the nightfighter.
3. Würzburg: Because Freya could not discern altitude, all zones had at least one Würzburg for height-finding (for example, FLAK gunnery radar).
Henaja and Himmelbett zones used dual Würzburgs for fighter guidance: one on the fighter, the other on the target.
In the Radar Search Phase of Henaja and Himmelbett scenarios, the umpire simply (and accurately) reports the hex distance and the direction from the nightfighter to the nearest bomber on the map.
Direction is given as the "clock" heading relative to the nightfighter's facing. If the direction does not correspond to an exact clock facing, the umpire declares the one clock direction he judges to be closest to the true situation on the board.
Exceptions:
- If there are no bombers on the map, the umpire reports "no activity."
- If the nightfighter is within within visual contact range of any bomber (i.e. within one hex), the umpire reports only "contact."
Reference source: GYGES Publishing, Nightfighter Control Methods.