Simple Sensor Rules for CT (work in progress)

[Supplement Four]

NOTE--

These sensor rules have been SCRAPPED in favor of a much simpler, easier to use, set of rules. You'll find those rules in this thread here: http://www.travellerrpg.com/cgi-bin/Trav/CotI/Discuss/ultimatebb.cgi?ubb=get_topic;f=44;t=000349


(INTRODUCTION)

I wanted some simple sensor rules for use with the space combat system described in the LLB's, The Traveller Book, and Starter Traveller.

I looked around at various systems (High Guard, Mayday, MT, TNE, Brilliant Lances, T4, and several home-grown sensor systems), and I couldn't find one that I was completely happy with.

Too many of them were too detailed! I like CT because it's simple rules!

I didn't want to, but I decided to create my own rules. Just like the Universal Game Mechanic (the task system I devised for use with CT), these sensor rules are to be extremely simple to use but still provide adequate detailed results.

And, the system must fit plug-n-play with existing CT rules.

In this instance, we're talking about the starship combat rules presented in the LBB 2, The Traveller Book, and Starter Traveller.

Given that, one Range Band (or hex, if using a hex grid or square grid to plot starship movement) under these rules is equal to that used in Starter Traveller (and LBB 2, TTB, etc).


RANGE BANDS

1 Range Band = 10,000 km.


Also, I am using the Universal Game Mechanic in my game--the simple task system designed for use with CT--so, I will be using it in these rules as well.

If you see something you like in these sensor rules, but you do not wish to use the UGM in your game, don't fret. You can easily use these rules as just a 2D dice roll.

In other words, these sensor rules will be compatible with official CT or the UGM. Either method of rolling dice/tasks will suffice.

One last thing....

These are not "finished" rules. They're close to being finished (and when they are finished, I'll post a nice clean copy of the rules), but I'm posting what I have here in an invitation to discussion.

If you've got two cents to add about these rules, then pony up to the plate. I'd like to hear from you.

And now, on to the CT sensor rules....

 

[Supplement Four]

NOTE--

These sensor rules have been SCRAPPED in favor of a much simpler, easier to use, set of rules. You'll find those rules in this thread here: http://www.travellerrpg.com/cgi-bin/Trav/CotI/Discuss/ultimatebb.cgi?ubb=get_topic;f=44;t=000349


(INTRODUCTION)

I wanted some simple sensor rules for use with the space combat system described in the LLB's, The Traveller Book, and Starter Traveller.

I looked around at various systems (High Guard, Mayday, MT, TNE, Brilliant Lances, T4, and several home-grown sensor systems), and I couldn't find one that I was completely happy with.

Too many of them were too detailed! I like CT because it's simple rules!

I didn't want to, but I decided to create my own rules. Just like the Universal Game Mechanic (the task system I devised for use with CT), these sensor rules are to be extremely simple to use but still provide adequate detailed results.

And, the system must fit plug-n-play with existing CT rules.

In this instance, we're talking about the starship combat rules presented in the LBB 2, The Traveller Book, and Starter Traveller.

Given that, one Range Band (or hex, if using a hex grid or square grid to plot starship movement) under these rules is equal to that used in Starter Traveller (and LBB 2, TTB, etc).


RANGE BANDS

1 Range Band = 10,000 km.


Also, I am using the Universal Game Mechanic in my game--the simple task system designed for use with CT--so, I will be using it in these rules as well.

If you see something you like in these sensor rules, but you do not wish to use the UGM in your game, don't fret. You can easily use these rules as just a 2D dice roll.

In other words, these sensor rules will be compatible with official CT or the UGM. Either method of rolling dice/tasks will suffice.

One last thing....

These are not "finished" rules. They're close to being finished (and when they are finished, I'll post a nice clean copy of the rules), but I'm posting what I have here in an invitation to discussion.

If you've got two cents to add about these rules, then pony up to the plate. I'd like to hear from you.

And now, on to the CT sensor rules....

 

[Supplement Four]

(BASELINE)

The Traveller Book gives us a baseline to use when comparing these sensor rules to official CT.

Civilian ships can detect out to a distance of about 150,000 km (15 Range Bands).

Military vessels can detect out to a distance of about 600,000 km (60 Range Bands).

These sensor rules will adhere (more or less) to those benchmarks.

 

[Supplement Four]

(BASELINE)

The Traveller Book gives us a baseline to use when comparing these sensor rules to official CT.

Civilian ships can detect out to a distance of about 150,000 km (15 Range Bands).

Military vessels can detect out to a distance of about 600,000 km (60 Range Bands).

These sensor rules will adhere (more or less) to those benchmarks.

 

[Supplement Four]

(ABOUT SENSOR SCANS AND SENSOR LOCKS)


Add a step to the space combat system used in TTB. The first phase, before the Movement phase, will be the Sensor Phase.

In this phase, ships will attempt two types of uses of their sensors: Sensor Scans and Sensor Locks.

Sensor Scans detect other vessels (and objects). A scan provides general information about the object scanned.

Sensor Locks provide detailed information about objects detected with the Sensor Scan.


The first thing a ship typically does when tumbling back into N-Space from a jump is conduct a Sensor Scan in order to detect any nearby objects.

Objects must be detected first from a Scan before they can be Locked.

Sensor Locks are required for an enemy vessel to be targeted in space combat.


Passive sensors can be used for both Sensor Scans and Sensor Locks, but Passive sensors are better suited to scans.

Some Active sensors can be used for both Sensor Scans and Sensor Locks, but most Active sensors are "directional" instead of "broadbeam" and therefore are only capable of Sensor Locks. Active sensors are better suited to Sensor Locks than Passive sensors, and Active sensors typically provide more detail about a detected object than a Passive Lock will provide.

Passive sensors typically have much greater range than Active sensors.

Passive sensors that can be used in both Sensor Scans and Sensor Locks have the capability of being focussed in a narrow tight beam. For example, the Passive EMS sensor will receive incoming data omni-directionally when in Scan mode but can also be focussed (as telephoto lens used on a camera) on a narrow target. This latter setting of the sensor is used for Passive Sensor Locks.


TYPES OF SENSORS

There are many types of sensors used in Traveller, and the list below is representative of what is available to a Traveller starship captain but not exhaustive.


RADAR is an Active sensor that detects objects by emitting radio energy across wide angles before detecting that energy when it bounces back from distant objects. Radar can be used for Active Sensor Locks, but is most often used for Active Sensor Scans.


LADAR is a similar Active sensor to radar except that it uses a tight beam laser rather than radio energy to bounce light off a target. Sand from sandcasters can make use of a ladar less effective. And, ladar can only be used for Sensor Locks (not Sensor Scans).


HRT is a High-Resolution Thermal detecting device--a Passive sensor that detects targets by their emmitted infrared radiation (heat). HRT can be used for either a Passive Sensor Scan or a Passive Sensor Lock.


EMS Active is an advanced version of radar which incorporates the use of wavelengths other than radio and includes sophisticated computerized image enhancement of the electro-magnetic spectrum. EMS Active can be used as either an Active Sensor Scan or Active Sensor Lock.


EMS Passive is an advanced (incorporates a camera) passive sensor that has the capabilities of HRT plus EMS direction finders and computerized image enhancement. EMS can be used for either Passive Sensor Scans or Passive Sensor Locks.


DENSITOMETERS detect an object's natural gravity and by doing so locate and classify the object according it it's particular density type. Densitometers can be used for either Passive Sensor Scans or Passive Sensor Locks.


LASER SENSORS, RADAR DIRECTION FINDERS, RADIO DIRECTION FINDERS, and NEUTRINO SENSORS are all Passive sensors that can locate and classify energy emissions, indicating size and power level status. These sensors can all be used in Passive Sensor Scans but only the neutrino sensor can be used in a Passive Sensor Lock.


Other sensors in Traveller, those not listed here, are possible and available to starship captains when upgrading their ships.


============================================

IS ALL THIS DETAIL NECESSARY?

Absolutely not.

I simply copy some of the information about sensors from other, non-CT, versions of Traveller in an effort to provide color and science-fiction atmosphere.

Classic Traveller is "rules lite", and these sensor rules will be no different.

It will not be necessary, when using these rules, to know which actual sensors are carried aboard a particular vessel. It will simply be assumed that the ship has some flavor of Active sensing ability and Passive sensing ability.

You need not worry about the particulars of any type of sensor.

If you want to get more detailed about the use of each sensor in your game, you can add modifiers to these rules for use of each type of sensor.

But, these rules will focus, simply, on Active and Passive Sensor Scans and Sensor Locks. The type of actual sensor (with only one exception, I think--Ladar) will never be required in these rules.

GMs can use the information above to add color and atmosphere to their descriptions of the type of information returned to a character making a sensor scan or lock during the game.

Or not...

These rules can easily be used in a typical manner of, "Hey, you got a lock on that vessel, you can fire at it now!" and move on with the starship combat scenario.

It's up to you.


============================================

One last note about the skill used when operating sensors....

Sensor Ops is, technically, the skill used to operate sensors, but Sensor Ops does not appear in the CT rules (because sensors are not dealt with in any detail in the CT rules set). Sensor Ops is a MT skill.

Any character with Navigation skill is considered as having Sensor Ops equal to a level of the character's Navigation skill minus 1. Therefore, a character with Navigation-1 also has Sensor Ops-0.

If Navigation skill is scarce in your campaign, consider using some flavor of the Computer skill as Sensor Ops. Computer minus two would be a fair choice (or rule that any character with any level of Computer also has Sensor Ops and a flat level zero).

 

[Supplement Four]

(ABOUT SENSOR SCANS AND SENSOR LOCKS)


Add a step to the space combat system used in TTB. The first phase, before the Movement phase, will be the Sensor Phase.

In this phase, ships will attempt two types of uses of their sensors: Sensor Scans and Sensor Locks.

Sensor Scans detect other vessels (and objects). A scan provides general information about the object scanned.

Sensor Locks provide detailed information about objects detected with the Sensor Scan.


The first thing a ship typically does when tumbling back into N-Space from a jump is conduct a Sensor Scan in order to detect any nearby objects.

Objects must be detected first from a Scan before they can be Locked.

Sensor Locks are required for an enemy vessel to be targeted in space combat.


Passive sensors can be used for both Sensor Scans and Sensor Locks, but Passive sensors are better suited to scans.

Some Active sensors can be used for both Sensor Scans and Sensor Locks, but most Active sensors are "directional" instead of "broadbeam" and therefore are only capable of Sensor Locks. Active sensors are better suited to Sensor Locks than Passive sensors, and Active sensors typically provide more detail about a detected object than a Passive Lock will provide.

Passive sensors typically have much greater range than Active sensors.

Passive sensors that can be used in both Sensor Scans and Sensor Locks have the capability of being focussed in a narrow tight beam. For example, the Passive EMS sensor will receive incoming data omni-directionally when in Scan mode but can also be focussed (as telephoto lens used on a camera) on a narrow target. This latter setting of the sensor is used for Passive Sensor Locks.


TYPES OF SENSORS

There are many types of sensors used in Traveller, and the list below is representative of what is available to a Traveller starship captain but not exhaustive.


RADAR is an Active sensor that detects objects by emitting radio energy across wide angles before detecting that energy when it bounces back from distant objects. Radar can be used for Active Sensor Locks, but is most often used for Active Sensor Scans.


LADAR is a similar Active sensor to radar except that it uses a tight beam laser rather than radio energy to bounce light off a target. Sand from sandcasters can make use of a ladar less effective. And, ladar can only be used for Sensor Locks (not Sensor Scans).


HRT is a High-Resolution Thermal detecting device--a Passive sensor that detects targets by their emmitted infrared radiation (heat). HRT can be used for either a Passive Sensor Scan or a Passive Sensor Lock.


EMS Active is an advanced version of radar which incorporates the use of wavelengths other than radio and includes sophisticated computerized image enhancement of the electro-magnetic spectrum. EMS Active can be used as either an Active Sensor Scan or Active Sensor Lock.


EMS Passive is an advanced (incorporates a camera) passive sensor that has the capabilities of HRT plus EMS direction finders and computerized image enhancement. EMS can be used for either Passive Sensor Scans or Passive Sensor Locks.


DENSITOMETERS detect an object's natural gravity and by doing so locate and classify the object according it it's particular density type. Densitometers can be used for either Passive Sensor Scans or Passive Sensor Locks.


LASER SENSORS, RADAR DIRECTION FINDERS, RADIO DIRECTION FINDERS, and NEUTRINO SENSORS are all Passive sensors that can locate and classify energy emissions, indicating size and power level status. These sensors can all be used in Passive Sensor Scans but only the neutrino sensor can be used in a Passive Sensor Lock.


Other sensors in Traveller, those not listed here, are possible and available to starship captains when upgrading their ships.


============================================

IS ALL THIS DETAIL NECESSARY?

Absolutely not.

I simply copy some of the information about sensors from other, non-CT, versions of Traveller in an effort to provide color and science-fiction atmosphere.

Classic Traveller is "rules lite", and these sensor rules will be no different.

It will not be necessary, when using these rules, to know which actual sensors are carried aboard a particular vessel. It will simply be assumed that the ship has some flavor of Active sensing ability and Passive sensing ability.

You need not worry about the particulars of any type of sensor.

If you want to get more detailed about the use of each sensor in your game, you can add modifiers to these rules for use of each type of sensor.

But, these rules will focus, simply, on Active and Passive Sensor Scans and Sensor Locks. The type of actual sensor (with only one exception, I think--Ladar) will never be required in these rules.

GMs can use the information above to add color and atmosphere to their descriptions of the type of information returned to a character making a sensor scan or lock during the game.

Or not...

These rules can easily be used in a typical manner of, "Hey, you got a lock on that vessel, you can fire at it now!" and move on with the starship combat scenario.

It's up to you.


============================================

One last note about the skill used when operating sensors....

Sensor Ops is, technically, the skill used to operate sensors, but Sensor Ops does not appear in the CT rules (because sensors are not dealt with in any detail in the CT rules set). Sensor Ops is a MT skill.

Any character with Navigation skill is considered as having Sensor Ops equal to a level of the character's Navigation skill minus 1. Therefore, a character with Navigation-1 also has Sensor Ops-0.

If Navigation skill is scarce in your campaign, consider using some flavor of the Computer skill as Sensor Ops. Computer minus two would be a fair choice (or rule that any character with any level of Computer also has Sensor Ops and a flat level zero).

 

[Supplement Four]

(STARSHIP SENSORS)


As just noted, these rules assume that a starship has some flavor of Active sensor(s) and some flavor of Passive sensor(s), and that the ship can use these sensors to make Active and Passive Sensor Locks and Sensor Scans.

The actual sensor being used (or available on the ship) is not important. Most ships are considered to have a collection of Active sensors in a cluster and a collection of Passive sensors in a cluster--all used for various types of sensing (not just combat).

In these rules, these clusters will be referred to as the "Active Array" and the "Passive Array".


================================================

Starships will only have two sensor tasks: one for Active sensors and one for Passive sensors.

Various DMs will modify either of these throws when they are made.

 

[Supplement Four]

(STARSHIP SENSORS)


As just noted, these rules assume that a starship has some flavor of Active sensor(s) and some flavor of Passive sensor(s), and that the ship can use these sensors to make Active and Passive Sensor Locks and Sensor Scans.

The actual sensor being used (or available on the ship) is not important. Most ships are considered to have a collection of Active sensors in a cluster and a collection of Passive sensors in a cluster--all used for various types of sensing (not just combat).

In these rules, these clusters will be referred to as the "Active Array" and the "Passive Array".


================================================

Starships will only have two sensor tasks: one for Active sensors and one for Passive sensors.

Various DMs will modify either of these throws when they are made.

 

[Supplement Four]

(SENSOR QUALITY)


The quality of either sensor array is denoted by a UGM task difficulty category.

For example: Standard Passive Array or Impossible Active Array.

Labeling the sensor arrays this way simply denotes the task involved in using the sensors.

The "Standard Passive Array" above requires a UGM task roll of Standard Difficulty.

(2D +mods for 8+).

The "Impossible Active Array" denotes that a UGM task of Impossible difficulty is required when using that sensor package.

(2D +mods for 18+).

Here are the Difficulty Categories for the UGM task system (for convienience). If you do not use the UGM task system in your CT game, then simply consider these the target numbers that must be achieved on a 2D roll when attempting a sensor task.

4+....Easy
6+....Routine
8+....Standard
10+...Difficult
12+...Challenging
14+...Formidable
16+...Insane
18+...Impossible


===============================================


Note that either the Active or Passive Arrays can have any of these eight quality ratings--the easier the task assigned to the sensor, the more expensive and sophisticated it is.

HIGHER QUALITY = LOWER TASK DIFFICULTY

(and lower task difficulty means greater sensor range).


===============================================


TYPICAL CIVILIAN SENSORS

A typical civilian vessel, such as a Free Trader or a Far Trader, will have:

STANDARD PASSIVE ARRAY
IMPOSSIBLE ACTIVE ARRAY


When deciding on the quality of sensors used in your game, keep this baseline in mind. Straight-off-the-assembly-line civilian vessels will have the arrays shown above, but a ship can always be upgraded. Maybe this will be the "pull" of an adventure--upgrading the ship's sensors.

These rules will not go into the cost of upgrading sensors--I leave this up to the GM. But, I will caution the GM in not being too generous with sensor quality. It wouldn't be unusual for a Routine or Easy quality sensor package to never be seen in a campaign (the range on these sensors is incredible).

You can pick any sensor quality you think appropriate for a vessel, but I, personally, would never make them better than Standard quality (unless we're talking about extreme, extremely expensive, or experimental sensor packages).

 

[Supplement Four]

(SENSOR QUALITY)


The quality of either sensor array is denoted by a UGM task difficulty category.

For example: Standard Passive Array or Impossible Active Array.

Labeling the sensor arrays this way simply denotes the task involved in using the sensors.

The "Standard Passive Array" above requires a UGM task roll of Standard Difficulty.

(2D +mods for 8+).

The "Impossible Active Array" denotes that a UGM task of Impossible difficulty is required when using that sensor package.

(2D +mods for 18+).

Here are the Difficulty Categories for the UGM task system (for convienience). If you do not use the UGM task system in your CT game, then simply consider these the target numbers that must be achieved on a 2D roll when attempting a sensor task.

4+....Easy
6+....Routine
8+....Standard
10+...Difficult
12+...Challenging
14+...Formidable
16+...Insane
18+...Impossible


===============================================


Note that either the Active or Passive Arrays can have any of these eight quality ratings--the easier the task assigned to the sensor, the more expensive and sophisticated it is.

HIGHER QUALITY = LOWER TASK DIFFICULTY

(and lower task difficulty means greater sensor range).


===============================================


TYPICAL CIVILIAN SENSORS

A typical civilian vessel, such as a Free Trader or a Far Trader, will have:

STANDARD PASSIVE ARRAY
IMPOSSIBLE ACTIVE ARRAY


When deciding on the quality of sensors used in your game, keep this baseline in mind. Straight-off-the-assembly-line civilian vessels will have the arrays shown above, but a ship can always be upgraded. Maybe this will be the "pull" of an adventure--upgrading the ship's sensors.

These rules will not go into the cost of upgrading sensors--I leave this up to the GM. But, I will caution the GM in not being too generous with sensor quality. It wouldn't be unusual for a Routine or Easy quality sensor package to never be seen in a campaign (the range on these sensors is incredible).

You can pick any sensor quality you think appropriate for a vessel, but I, personally, would never make them better than Standard quality (unless we're talking about extreme, extremely expensive, or experimental sensor packages).

 

[Supplement Four]

(SENSOR POWER)


A ship's Power Plant feeds power to the ship's sensors.

Consider the ship's Power Plant code to be the usual Traveller hexidecimal notation (where A = 10; B = 11; C = 12; I and O are not used to prevent confusion with 1 and 0; etc.).


================================================

A ship's PP code is used as a positive modifier on the Sensor task. A more powerful Power Plant drives more powerful sensors, and those sensors will have greater range (and a greater range where the probability of detection is 100%).

Thus, a Free Trader, mounting the usual civilian sensors will have a Standard Passive Array and an Impossible Active Array. The Free Trader mounts a Type A Power Plant.

Thus, this ship's two sensor tasks are:

Passive Sensor Task = 2D +10 for 8+

Active Sensor Task = 2D +10 for 18+

 

[Supplement Four]

(SENSOR POWER)


A ship's Power Plant feeds power to the ship's sensors.

Consider the ship's Power Plant code to be the usual Traveller hexidecimal notation (where A = 10; B = 11; C = 12; I and O are not used to prevent confusion with 1 and 0; etc.).


================================================

A ship's PP code is used as a positive modifier on the Sensor task. A more powerful Power Plant drives more powerful sensors, and those sensors will have greater range (and a greater range where the probability of detection is 100%).

Thus, a Free Trader, mounting the usual civilian sensors will have a Standard Passive Array and an Impossible Active Array. The Free Trader mounts a Type A Power Plant.

Thus, this ship's two sensor tasks are:

Passive Sensor Task = 2D +10 for 8+

Active Sensor Task = 2D +10 for 18+

 

[Supplement Four]

(SENSOR SENSITIVITY)


Each Array, whether Active or Passive, will have a sensitivty equal to the starship's computer model number.

The sensitivty of an Array denotes the number of Range Bands counted before a -1DM is applied to the sensor task roll.

Thus....

A Free Trader, with a Model 1bis computer, will subtract -1DM from the sensor task roll for every Range Band between the ship and the target.

Remember that Range Bands equal 10,000 km each, so for every 10,000 km, apply a -1DM to the sensor roll.


FREE TRADER
Power Plant A
Model 1 Computer

Standard Passive Array
Impossible Active Array


If this ship were to attempt detection of an enemy vessel at 80,000 km using Passive sensors, the roll would be:

2D +10 -8 for 8+

The "+10" comes from the ship's Power Plant. The "-8" comes from the range to the target (80,000 km divided by a sensor sensitivity of 1 = 80,000....80,000 / 10,000 = 8 Range Bands).

This roll will distill down to:

2D for 6+

The Free Trader will detect the enemy vessel on a 2D roll of 6 or better.

Other DMs will apply to this roll (Sensor Ops skill, for example)--I'm just showing you the basics of the system.


=================================================

Note that military vessels and large scout ships will have sensors with much greater sensitivity (and range).

The Type T Patrol Cruiser has a Model 3 computer, giving its sensors a sensitivity rating of 3 (-1DM to sensor task every 30,000 km).

The Type C Mercenary Cruiser mounts a Model 5 computer, giving it some of the most sensitive sensors seen in Traveller. Every 50,000 km of range requires a -1DM to the sensor task roll. (This ship will have a large range around the vessel where detection is 100%).

The Donosev class Scout Survey Vessel sports Model 5 computer, giving its sensors the incredible detection capability seen in the Broadsword class Mercenary Cruiser describe in the above paragraph.

 

[Supplement Four]

(SENSOR SENSITIVITY)


Each Array, whether Active or Passive, will have a sensitivty equal to the starship's computer model number.

The sensitivty of an Array denotes the number of Range Bands counted before a -1DM is applied to the sensor task roll.

Thus....

A Free Trader, with a Model 1bis computer, will subtract -1DM from the sensor task roll for every Range Band between the ship and the target.

Remember that Range Bands equal 10,000 km each, so for every 10,000 km, apply a -1DM to the sensor roll.


FREE TRADER
Power Plant A
Model 1 Computer

Standard Passive Array
Impossible Active Array


If this ship were to attempt detection of an enemy vessel at 80,000 km using Passive sensors, the roll would be:

2D +10 -8 for 8+

The "+10" comes from the ship's Power Plant. The "-8" comes from the range to the target (80,000 km divided by a sensor sensitivity of 1 = 80,000....80,000 / 10,000 = 8 Range Bands).

This roll will distill down to:

2D for 6+

The Free Trader will detect the enemy vessel on a 2D roll of 6 or better.

Other DMs will apply to this roll (Sensor Ops skill, for example)--I'm just showing you the basics of the system.


=================================================

Note that military vessels and large scout ships will have sensors with much greater sensitivity (and range).

The Type T Patrol Cruiser has a Model 3 computer, giving its sensors a sensitivity rating of 3 (-1DM to sensor task every 30,000 km).

The Type C Mercenary Cruiser mounts a Model 5 computer, giving it some of the most sensitive sensors seen in Traveller. Every 50,000 km of range requires a -1DM to the sensor task roll. (This ship will have a large range around the vessel where detection is 100%).

The Donosev class Scout Survey Vessel sports Model 5 computer, giving its sensors the incredible detection capability seen in the Broadsword class Mercenary Cruiser describe in the above paragraph.

 

[Supplement Four]

(SENSOR TASKS)


This is a simple system. All you need to know is (1) your ship's PowerPlant code; (2) your ship's Computer Model number; and (3) the range to the target.

If you know these three things, you can roll a sensor task using these rules.

Well...you'll have to know the quality of your sensors too...but that's just a matter of assigning a difficulty to the sensor task.


------------------------------------------------
--TO REVIEW--
------------------------------------------------

SENSOR QUALITY is the task associated with the Active or Passive sensor array.

SENSOR POWER is denoted by the ship's PowerPlant code. This number is added to the sensor task.

SENSOR SENSITIVITY is denoted by the ship's Computer Model number. Divide range to the target by this number, then divide that result by 10,000. This number is subtracted from the sensor task.


------------------------------------------------

------------------------------------------------


THAT'S IT!

Do those three things, and you have the core mechanic for these sensor rules.

Remember that there are only two sensor task rolls for each ship: A roll for the Active Array, and a roll for the Passive Array.

Other DMs may apply to this roll, but I will discuss those below.

 

[Supplement Four]

(SENSOR TASKS)


This is a simple system. All you need to know is (1) your ship's PowerPlant code; (2) your ship's Computer Model number; and (3) the range to the target.

If you know these three things, you can roll a sensor task using these rules.

Well...you'll have to know the quality of your sensors too...but that's just a matter of assigning a difficulty to the sensor task.


------------------------------------------------
--TO REVIEW--
------------------------------------------------

SENSOR QUALITY is the task associated with the Active or Passive sensor array.

SENSOR POWER is denoted by the ship's PowerPlant code. This number is added to the sensor task.

SENSOR SENSITIVITY is denoted by the ship's Computer Model number. Divide range to the target by this number, then divide that result by 10,000. This number is subtracted from the sensor task.


------------------------------------------------

------------------------------------------------


THAT'S IT!

Do those three things, and you have the core mechanic for these sensor rules.

Remember that there are only two sensor task rolls for each ship: A roll for the Active Array, and a roll for the Passive Array.

Other DMs may apply to this roll, but I will discuss those below.

 

[Supplement Four]

(TESTING THE BASELINE)


Let's test what we've discussed against our baseline above.

Remember, our baseline is...

Originally posted by WJP:
(BASELINE)

The Traveller Book gives us a baseline to use when comparing these sensor rules to official CT.

Civilian ships can detect out to a distance of about 150,000 km (15 Range Bands).

Military vessels can detect out to a distance of about 600,000 km (60 Range Bands).

These sensor rules will adhere (more or less) to those benchmarks.

===============================================


Let's use a Type A Free Trader as our test civilian ship.

FREE TRADER
PowerPlant A
Computer Model 1

Standard Passive Array
Impossible Active Array


Since Passive sensors typically have greater range than Active sensors, I'll assume that the detection range of 150,000 km speaks to the range of the Passive sensors. We'll do a Passive Scan and see how this compares to the CT guideline.

Standard Passive Array used to scan target at 150,000 km.

2D +10 -15 for 8+

Translates to...

2D for 13+

As you can see, this is about what we need. There will be a DM or two (Sensor Ops skill, for example) that will get our target number down a bit so that it is possible to make it on a 2D throw.

Obviously, though, 150,000 km is about the max range for this ship's Passive sensors (depending on the other DMs used on the throw).

I'd say that test was passed.


===============================================


Now, let's test a military vessel against our CT mandated baseline. The typical Type T Patrol Cruiser is a good choice.


TYPE T PATROL CRUISER
PowerPlant H
Computer Model 3

Standard Passive Array
Challenging Active Array


Again, we'll use the Passive Scan for our test, and this time, we need to test an object out at 600,000 km.

2D +17 -20 for 8+

Which translates to...

2D for 11+


And, that's exactly where we need that roll to be--that's close to max range of the sensor. This roll only has an 8% chance of success (but other DMs will alter this a bit).

It looks like we've passed both of our baseline tests.

 

[Supplement Four]

(TESTING THE BASELINE)


Let's test what we've discussed against our baseline above.

Remember, our baseline is...

Originally posted by WJP:
(BASELINE)

The Traveller Book gives us a baseline to use when comparing these sensor rules to official CT.

Civilian ships can detect out to a distance of about 150,000 km (15 Range Bands).

Military vessels can detect out to a distance of about 600,000 km (60 Range Bands).

These sensor rules will adhere (more or less) to those benchmarks.

===============================================


Let's use a Type A Free Trader as our test civilian ship.

FREE TRADER
PowerPlant A
Computer Model 1

Standard Passive Array
Impossible Active Array


Since Passive sensors typically have greater range than Active sensors, I'll assume that the detection range of 150,000 km speaks to the range of the Passive sensors. We'll do a Passive Scan and see how this compares to the CT guideline.

Standard Passive Array used to scan target at 150,000 km.

2D +10 -15 for 8+

Translates to...

2D for 13+

As you can see, this is about what we need. There will be a DM or two (Sensor Ops skill, for example) that will get our target number down a bit so that it is possible to make it on a 2D throw.

Obviously, though, 150,000 km is about the max range for this ship's Passive sensors (depending on the other DMs used on the throw).

I'd say that test was passed.


===============================================


Now, let's test a military vessel against our CT mandated baseline. The typical Type T Patrol Cruiser is a good choice.


TYPE T PATROL CRUISER
PowerPlant H
Computer Model 3

Standard Passive Array
Challenging Active Array


Again, we'll use the Passive Scan for our test, and this time, we need to test an object out at 600,000 km.

2D +17 -20 for 8+

Which translates to...

2D for 11+


And, that's exactly where we need that roll to be--that's close to max range of the sensor. This roll only has an 8% chance of success (but other DMs will alter this a bit).

It looks like we've passed both of our baseline tests.

 

[Supplement Four]

(INTRODUCTION...CORE MECHANIC...AND NOW DM's)


OK, I've introduced this system to you and shown you the core mechanic. Now it's time to start discussing DMs needed on the sensor task rolls.

I haven't thought all of this through yet, and this is where your input is welcome.

I'll list some DMs I think appropriate to the two sensor tasks I've described above. As we discuss these, we can tweak them and turn this into a superior Classic Traveller sensor system for CT space combat.

 

[Supplement Four]

(INTRODUCTION...CORE MECHANIC...AND NOW DM's)


OK, I've introduced this system to you and shown you the core mechanic. Now it's time to start discussing DMs needed on the sensor task rolls.

I haven't thought all of this through yet, and this is where your input is welcome.

I'll list some DMs I think appropriate to the two sensor tasks I've described above. As we discuss these, we can tweak them and turn this into a superior Classic Traveller sensor system for CT space combat.