Concealed M-Drive Power

Ol'Weedy

Banded Mongoose
I was using High Guard (Mongoose 2nd Edition) to create a stealth small craft, and decided it HAD to have a concealed manoeuvre drive.
I went with M-Dive 8, perfectly willing to settle for Thrust 4 performance, AND the tonnage\cost penalty.
The issue I had came when figuring out the power usage. Does it use as much power as a Thrust 8 craft, or a Thrust 4.
While a by the rule explanation would lead me to believe it would suck juice like a Thrust 8, common sense would point me toward Thrust 4 consumption.
After all, isn't the point of concealing the drive, to hide emissions? How would applying more power help?
Thoughts?
 
It is an m-drive 8 hidden behind a bulkhead. It still requires the EP input of an m-drive 8.

An interesting option would be a bulkhead that can be moved out of the way - folding, sliding or iris like - so that you can switch between "stealth" mode and full thrust.
 
What shall we term it, energy bloom? Input remains the same, but the output is diffused.

But in theory, you could then stick a normal manoeuvre drive behind (a) specially constructed bulkhead/s.
 
It's always better to see what we are on about for the benefit of those who may not have seen this:
Concealed manoeuvre drives are contained within
ship bulkheads but must be within three metres of the
accelerating surface of the ship. Concealed manoeuvre
drives add 25% to the tonnage and cost of the drive.
The additional tonnage comprises a system that
contains and exhausts thruster plate ionisation out of
specially designed ports, reducing their detectability
to almost nil. Concealed manoeuvre drives cut
performance in half (round down), so a ship with Thrust
2 is reduced to 1 and so on. These drives are designed
to operate within confinement, so simply removing the
outer bulkhead does not add to their performance.
That last bit shoots down my idea, but how about adding an additional cost (a further 25% should do it) so that the bulkhead can iris out of the way and full thrust be achieved?
 
About the same as a cargo hatch.

Actual rearrangement beyond a simple open and close would require more complex machinery.
 
After all, isn't the point of concealing the drive, to hide emissions? How would applying more power help?
Thoughts?
The rules as written in the Sensors chapter indicate that any use of the power plant results in a DM+1 to sensor detection. The power output is not factored, so needing more power won't matter. If you purchase Thrust 8, you get Thrust 4 performance, but must provide power for Thrust 8. We'll have to clarify that on the next edition.
 
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The rules as written in the Sensors chapter indicate that any use of the power plant results in a DM+1 to sensor detection. The power output is not factored, so needing more power won't matter. If you purchase Thrust 8, you get Thrust 4 performance, but must provide power for Thrust 8. We'll have to clarify that on the next edition.
As it is at the moment you would be better off buying an m-drive 4 and not concealing it.

What would make sense would be a concealed m-drive counts as thrust 0 on the sensor table for initial detection. This sentence sums it up:
The additional tonnage comprises a system that
contains and exhausts thruster plate ionisation out of
specially designed ports, reducing their detectability
to almost nil.
So a concealed m-drive has a signature of 0.
 
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What exactly is being ionised to cause detectable thruster plate ionisation in the first place? And why are these emissions more detectable than the power plant emissions?
Unless it is something consumable then the thruster plate itself must be being ionised, in which case it will require replacement after a bit of use.

Shouldn't a reaction drive be a lot easier to detect - say double its thrust as a sensor signature?
 
Had a discussion about this recently and, if it were possible, I'd file an addendum to those sensor rules that would go something like this:

Target is operating manoeuvre drive+1 per Thrust A target ship applying Thrust 3 provides DM+3 on an opposing ship’s sensor check.
Target is operating reaction drive+1 per ThrustA target ship using a reaction drive to apply Thrust 3 provides DM+3 on an opposing ship’s sensor check.
Target is operating manoeuvre drive+1 per Thrust above Thrust 3A target ship applying Thrust 4 provides DM+1 on an opposing ship’s sensor check.

We overly nerfed stealth and I believe this would put things back where we'd want them.
 
I still don't see the benefit of a concealed m-drive.
You have to make it clear that a concealed drive has no signature.

Also a reaction drive is likely to be a fusion or plasma exhaust, the signature of which is so easily detected by thermal sensors as to not require a roll of the dice.

Is there any milage to be gained by thinking of this from an energy standpoint?
You have active sensors of variable power and yet only one DM, surely it is easier to locate a ship running a 6EP active sensor than one using a 1EP active sensor?

Anyway this is how I would do it:
FactorDMExample
TL difference between ships.
+1 per higher TL
A TL15 ship receives DM+3 to detect a TL12 ship.
Target running active sensors.
+(EP used by active sensor)
Target ship is operating a 2EP active radar/lidar sensors.
Target running passive sensors only.
+0
Target ship is operating visual, heat, EM and other passive sensors only.
Target is operating manoeuvre drive.
+1 per Thrust
A target ship applying Thrust 3 provides DM+3 on an opposing ship’s sensor check.
Target is operating a concealed manoeuvre drive.
+0
Target ship has a concealed manoeuvre drive.
Target is operating a reaction drive.
+2 per ThrustA target ship applying Thrust 3 via a reaction drive provides DM+6 on an opposing ship’s sensor check.
Target is operating power plant.
+1Target is operating its power plant at minimum level (basic ship systems) or higher.
Transponder or radio comms.
+6
Target ship is running its transponder or radio comms.
Extended sensor array deployed.
+2The ship is equipped with an extended array and it is deployed.
Stealth.
-2, -4 or -6
Target ship has stealth coating. See Stealth on page 77 for more information.
 
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I barely passed Combined Science, but I think that whatever covers the thrusters acts as a membrane, which ions pass through.

It's a glower, not a grower.

Regarding detectability, could be just energy output, regardless of source, modified by techniques that reduce detectability.
 
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