General Detection Penalties
Created by: The Kitsune
Posted to Palladium Mailing List on November 12, 1998 @ 11:08 AM
There are many factors that effect the ability for targets to be detected. The factors include vehicles
hiding behind, the target being behind the horizon, and the radar absorbent materials of stealth aircraft.
This addresses any of these but is meant for medium and larger vehicle. Individuals are much smaller
targets and must be treated with caution although these rules and suggestions can be partially applies to
them as well.
A common tactic for both aircraft and ground targets is to use the available terrain to reduce their
chance of being detected. This table gives penalties for various types of terrain. Detect ambush skill
can negate terrain penalties by detecting any damage to foliage or terrain, running and screaming people
in cities, and disturbed animals. This cannot be done at long range, by radar, or while fast moving. In
most cases, this cannot be done at night either. Do not add terrain penalties together, just use the
highest terrain penalties. Visual penalties are based on the assumption that targets are of low visibility
colors. Add a bonus to detection by visual means if this is not the case. Generally, visual detection without
special equipment is virtually impossible over long distances but a full moon may allow some chance of
detection through visual means.
- No Line of Site: No chance of detection. This includes targets behind hill, mountains, and buildings.
- Completely Hidden by Foliage or Trees: -50% detection penalty using radar (metal objects reflect more radar
than trees) and no detection chance with visuals.
- Mostly Hidden by Terrain: -50% detection penalty using radar or by visual means
- Mostly hidden by Foliage or Trees: -35% detection penalty using radar (metal objects reflect more radar than
trees) and -50% detection penalty using visual means of detection.
- Partially Hidden by Terrain: -35% detection penalty using radar or by visual means.
- Partially hidden by Foliage or Trees: -20% detection penalty using radar (metal objects reflect more radar
than trees) and -35% detection penalty using visual means of detection.
- Low Level over Rough Terrain: -20% detection penalty using radar or by visual means.
- Low Level over Low Level Terrain with light Foliage: -10% detection penalty using radar (metal objects
reflect more radar than trees) and -20% detection penalty using visual means of detection.
- Line of Site: Line of site for radar system is slightly longer than it is for visual means but listed
below is a general table of line of site based on the height of objects. It has a minor amount of math
but it is still relatively simple. It can be set up on a spreadsheet or using a scientific calculator
Distance in nautical miles = 1.17 x (height)^0.5
Height is based on the observers eyes in feet above the ground to calculate distance to the horizon. To
calculate for targets further above, you calculate the distance to the horizon for the observer and
the calculate the distance to the horizon for the target. These two numbers are added together and
you get the distance you can see the target.
There are some other factors but they can be ignored for most role playing games. These are that there
is a problem with the fact that light rays bend (refract) as they pass through water vapor. And, of
course, there's more water vapor the closer you are to the sea surface. So, getting a range on a
target that is over the horizon over water is pretty much hit or miss (pun intended). That's one of
the reasons optical systems lose their accuracy the farther away they are from a target.
Modified Stealth Penalties
Many vehicles are constructed out of material or have a coating of materials that absorb radar signals.
These are very effective but there is a limitation that the stealth is less effective the closer the radar
transmitter is to the target. This information is primarily listed for air vehicles but is also applicable
to ground vehicle with a small amount of work. Most standard stealth aircraft have the same effectiveness
the same effectiveness as the Coalition Talon Stealth fighter which has a detection probability of -80% to
be detected. Terrain penalties are also listed and they can be used for non stealth aircraft as well as
stealth aircraft. The effects of terrain are determined by the position of the radar unit as well. A Radar
transmitter in the air or on a high hill or mountain will allow for far better detection of targets.
Read Sensory Skill
If the read sensory skill of an Individual or a system is about 98%, record how high above 98% the skill
is and penalties are subtracted from that number.
Effects of Range
- If the target is from three quarters maximum to maximum range from radar transmitter, the penalty to detect
targets has full penalties (-80% in the Coalition Talon and similar aircrafts case).
- If the target is from half to three quarters maximum range from radar transmitter, the penalties to detect
target has three quarters penalties (-60% in the Coalition Talon and similar aircrafts case).
- If the target is from one quarter to half maximum range from radar transmitter, the penalties to detect
target has half penalties (-40% in the Coalition Talon and similar aircrafts case).
- If the target is less than one quarter of maximum range from radar transmitter, the penalties to detect
target has one quarter penalties (-20% in the Coalition Talon and similar aircrafts case).
General-Detection-Penalties.php -- Revised: January 27, 2021.