in Second World War at Sea
By Steve Cabral
The development of radar was one of the
defining events of World War II. In Second
World War at Sea games, however, radar
is virtually ignored. This optional module
expands its role in the game.
Radar was first conceived in 1904 in Germany
and derived by two independent designers,
but the Imperial Navy felt there was no need
to detect ships one couldn’t see and
showed it the door. In the 1920s radar as
we know it was accidentally discovered in
the U.S., and the U.S., Great Britain, France
and Germany all began radar development thereafter.
Radar was originally in the meter range,
and during the war the U.S. and Great Britain
developed centimeter wavelengths that Germany
declared impossible. German naval radar fell
hopelessly behind until a British centimeter
set was captured. (Interestingly, the German
Z-52 appears to have an American radar and
director system aboard as designed, but this
has not been confirmed; many German radar
developments are locked away in Allied archives.)
Many national and military leaders distrusted
radar, and in the very traditional and conservative
navies the anti-radar forces were strong.
Most German and some American commanders,
particularly submariners, were in constant
fear that radar use could be triangulated
back to them like radio. So Germans almost
always kept their sets off as did many U.S.
sub commanders early in the war.
The U.S. was fully radar-equipped by July
1943. During the somewhat reduced pace in
operations after Guadalcanal the fleet was
re-equipped with excellent electronics, and
American carriers mounted as many as eight
different types of sets.
The British took longer to get radar aboard
ships because they were kept so busy and at
sea so often, and needed to equip destroyers
and escorts for the U-boat war. Some British
ships like the Sheffield had surface
search radar at war’s start but most
got their first set when the fire control
Type 284 was added in summer 1941.
The Japanese had little use for radar despite
experiments starting in the 1930s. The Italians
interestingly embraced radar and added Gufo
(owl) sets as quick as they could, or German
sets when available, and they weren’t
afraid to use them. The French managed to
get radar aboard three ships.
Misuse and Improvements
Early on, radar was often misunderstood and
misused. Admiral Lancelot Holland, aboard
Hood, ordered Prince of Wales
to use Type 284 radar to search a certain
arc for Bismarck while he used his
to search another arc. Type 284 is gunnery-control
radar and has a limited arc, unlike search
radar, which usually covered 180 to 360 degrees
depending on installation and nationality
factors. The Prince of Wales captain
signaled back — this being the Prince
of Wales after all — that his radar
didn’t work. Prince of Wales
then requested to turn on his powerful search
radar! This was denied because it would jam
Hood’s T-284 radar.
In November 1942 Admiral Callaghan put together
a scratch cruiser and destroyer task force
to stop a massive Tokyo Express battleship
fleet heading to Guadalcanal. He placed his
destroyers with ineffective, early-model SC
radar in the lead, his cruisers some with
no radar in the center and his brand new Fletcher-class
destroyers with improved microwave SG radar
in the rear. The U.S. fleet was virtually
wiped out, but the Fletchers, which
could “see” the Japanese ships,
The following Second World War at Sea
rules cover contact by sea and air search
plus radar’s use in naval gunnery. Each
country’s use of radar is separate and
replaces current radar bonuses for U.S. and
British task forces.
French and Japanese Radar
Strasbourg received air warning radar
in 1941, and Jean Bart and Richelieu
received the same sets in 1942. Despite
Free French upgrades, however, treat French
ships as having no radar. No special radar
rules apply to Japanese ships due to their
excellent spotting capability.
German radar (FuMO) was usually turned off.
Roll 1D6 at the start of the scenario. If
the result is a 6, each German task force
with radar-equipped ships gets +1/–1
on the Contact Table.
Starting in 1942 all non-active ships use
passive radar (detecting radar signals only).
Whenever a task force searches for them with
a modifier for radar, the German has the option
to use passive detection to evade the search.
If the search roll results in detection the
German may re-roll the detection die; if it
indicates no contact he remains unfound. If
the German force is still found proceed to
combat, but Germany automatically loses initiative.
Date of radar equipage in Kriegsmarine:
- CA+: 1939
- CL: 7/41
- DD: 1942
A British task force has radar whenever one
of the ships listed below is included after
the given date, or if it contains six or more
unnamed vessels not counting CL ‘C’
class. All British task forces are radar-equipped
as of 1945.
A task force is considered British if 50%
or more of its ships are British, except in
the Pacific. A task force is considered American
if more than 50% of its ships are American,
or if it’s in the Pacific.
A radar-equipped task force gets +1/–1
on the Contact Table. All gunnery combat is
+1 for named ships equipped with radar.
Date of fire-control radar equipage:
- Arethusa: 3/1/42
- Aurora: 4/1/41
- Belfast: 1/1/42
- Berwick: 1/1/41
- Birmingham: 3/1/42
- Dido: 6/1/43
- Edinburgh: 3/1/42
- Enterprise: 10/1/43
- Fiji: 12/1/41
- Glasgow: 6/1/42
- Hood: 3/1/41
- Kent: 1/1/41
- Kenya: 12/1/41
- King George V class: all
- Leander: 1/1/42
- Liverpool: 12/1/41
- London: 5/43
- Malaya: 7/1/41
- Manchester: 2/1/42
- Mauritius: 2/1/42
- Neptune: 1/1/41
- Newfoundland: As built
- Nigeria: 8/1/41
- Norfolk: 9/1/41
- Orion: 1/1/41
- Phoebe: 4/1/42
- Ramilles: 1/1/43
- Renown class: 1/1/41
- Revenge: 12/1/41
- Royal Sovereign: 1/1/43
- Sheffield: 6/1/41
- Valiant: 4/1/43
- Warspite: 1/1/41
- Air and surface search equipage: 11/41
- CV and DD: all
- Air and surface search equipage: 1/45
- All other ships.
A radar-equipped task force gets +1/-1 on
Contact Table. An Italian task force has radar
when it includes one of the ships listed below
after the given date.
Air and surface search (Gufo or FuMO): 7/42
- Capitani Romani class: as launched
- Vittorio Veneto
Air search (Gufo): 8/43
A U.S. task force has radar if it includes
one of the ships listed below after the given
date, or if it contains six or more unnamed
vessels not counting four-piper DD classes.
All U.S. task forces are radar-equipped
as of July 1943.
A task force is considered American if more
than 50% of its ships are U.S. or if it’s
in the Pacific Ocean. A task force is considered
British if 50% or more of its ships are British,
except in the Pacific.
A radar-equipped task force gets +1/–1
on Contact Table only in ocean hexes. All
gunnery combat is +1 from named ships after
6/43 and +2 after 6/44. The “search
and fire control as built” group also
get +1 prior to 7/43.
Search and fire control as of 7/43:
Air search only as of 1939:
- All CV
- New York class
- West Virginia
Air and surface search equipage as of 7/42:
Search and fire control as built:
- Baltimore class
- Cleveland class
- Iowa class
- North Carolina class
- South Dakota class
Whenever an air strike arrives at a task
force equipped with active radar, it is spotted
on a roll 1-3 (1-4 for Allies from 1942 onward).
A task force using only passive radar spots
the strike on a die roll of 1.
If it spots the strike, the task force may
roll one die. On a 6 it ducks into a rain
squall and may not be attacked. The strike
may hit another task force in the same hex
if its intended target evades.
Lucky Ship Option: The U.S.S. Enterprise
seemed to tow a squall wherever she went.
Using this option a task force that includes
her ducks into a squall on a 5 or 6. “Big
E” got lucky a lot in the Pacific but
the other carriers took the brunt of strikes
aimed at her.
When used at night, radar allows a task
force to detect the enemy at daytime visibility
distances. Ships with gunnery radar may fire
at ships that cannot be seen.
When firing at a target beyond visibility
all fire must be directed at the largest target.
If targets are equidistant, split the fire
randomly among them. American task forces’
search radar is negated for surface detection
when a battle takes place in land hexes prior
to 1944. U.S. fire-control radar does work.
Radar may be lost when a ship is hit by
gunnery fire. For each gunnery phase hit (not
per individual hit) roll one die. A result
of 6 removes radar until the ship returns
Unlucky Ship Option: Littorio-class
BB and 1942 U.S.S. South Dakota roll
not only for radar loss but also for electrical
failure in each movement impulse. On a “6”
the ship loses electrical power and can move
only straight and can not fire. This lasts
for two movement and gunnery impulses. This
can only occur once per turn but carries over
into an extended battle. Littorio-class
ships are not affected by this in Clear weather.
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