Alfisti's picture
Systems Integration - Pass03
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Work on sensor suite integration into the basic spaceframe has been continuing, with the latest pass covering three areas: refining the navigational radio telescope installation, initial passive sensor placement, and long range long-range investigative sensor placement.

Navigational Radiotelescope

Input from the astronomy team has resulted in the adoption of a forward facing radio telescopy array for long range navigation, with the intention to utilise field technology under development at ATCA to supplement the necessarily smaller dish utilised for this installation. “Small” is, however, a relative term, leaving the remaining complication of having no space for a redundant backup dish of similar capability due to the vessel’s intentionally narrow forward profile, and the mirrored ventral location being taken by the boat bay.

As such, instead of a full power array, a smaller reserve telescope dish has been incorporated allowing, should the main array be damaged beyond feasible repair, limp-home capability. This is currently located on the port side of the boat bay, though this remains a provisional location.

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Passive Sensors

Also undertaken during this integration pass is commencement of implementation of passive tactical sensor arrays. While the actual makeup of mounted equipment remains to be finalised it is envisaged that each mount will contain a full, broad spectrum, sensor package capable of, at a minimum, intensity and direction finding. In this manner, by the use of multiple arrays for triangulation, the crew will be able to undertake ranging and Target Motion Analysis (TMA) for tactical and navigational (including, potentially, mapping) purposes.

It is anticipated that these combined should give good coverage around the forward approximately 300 degrees of the hull. It is expected however that interference from drive wash will severely degrade or even completely nullify coverage across the stern 60 degrees at anything more than minimal outputs.

The Naval Architecture team is also currently investigating the feasibility of a towed passive array to help supplement the hull mounted sensor suite by increasing base sensor separation.

This, however, is likely to come at a cost to vessel manoeuvrability during deployment and operation. While it is envisaged that the towed array chassis would incorporate its own limited guidance and RCS, hard manoeuvring with it deployed is not recommended due to the risk of potential wire break or collision with the main hull. With that in mind, it is however recommended that a minimum acceleration of at least 0.1G be maintained during deployment and scanning to maintain wire tension and assist control of the array. While this minimum should be observed it is also noted that the towed array would necessarily sit directly in the vessel’s engine wash, thus negating its utility at higher outputs anyway.

Despite its limitations, the potential utility and advantage offered by the towed array (especially for a vessel doing its best impression of an empty patch of space) is seen as worthwhile enough to continue investigations.

Lonf Range Investigative Sensors

This array is still very much under development, but is currently envisaged as a much higher fidelity, narrow aperture, sensor suite, useful for gathering detailed information at a distance (on a system-wide level, rather than over superluminal ranges). However, due to its narrow focus, it is likely to be near useless in tactical applications.

 

Comments

mattm's picture

The concept of the towed array is a good one - it's the approach used by submarines to achieve the same results in terms of improved sensor improvement. A physically connected/towed approach might b ethe best approach underwater given the pressure and currents exerted by the ocean, but in space a semi-autonomous approach could work? Along the lines of a computer-controlled drone with a narrow-band link to the vessel. 

This would provide greater flexibility - the sensor drones could operate all around the vessel, and you could conceivably have more than one in operation at any one time. The computer could take care of launch, positioning and docking based on a mission profile chsoen by the crew (with theopetion to assume manual control if needed?).

Alfisti's picture

I think it would definitely offer a more flexible and powerful option to be able to utilise multiple sensor drones. I could particularly see it being useful in that a drone constellation could be oriented in the direction of a contact to refine data much faster from that direction.

As to putting it into practice: I think it will really come down to how much capability could be crammed into a drone body, whilst also keeping said drone small enough to make carrying multiple units feasible. Compared to the single towed array, endurance of the system would likely be much shorter (as the drones would necessarially require onboard power sources, rather than being fed by the ship's reactor), and recovery times longer. That latter would be especially true as, if a rapid escape was required with the drones deployed, the main vessel would either need to hold fast long enough to recover them as it is unlikely they could match the mothership's acceleration with their smaller powersources. It would be something to look into. However, I do think the additional sensor capability may well be worth the tradeoffs. Once we have the drive specs nailed down there might even be some overhead increase the hull volume around the drone bay to allow both systems?

Comms to deployed drones would be the other thing to investigate as we will still be wanting the vessel to be able to do its best impression of a hole in space with the system deployed, and thus to minimise the chance of any stray radiated energy. Perhaps a narrow-beam laser system? 

 

alexp's picture

Torpedoes also take advantage of the vessel's superior sensor systems to guide them after launch. A narrow-beam laser system is envisaged for this, to replace what was traditionally (on subs) a wire. The transmitter on the ship keeps track of the torp for as long as it can, until the ship has to maneuver away (in which case the wire is "cut"). You'd probably have more options for keep in touch with a drone (more transmitters maybe?).

Torps are inherently expendable, though. I imagine you'd need to accept the fact you might lose a few drones if extreme maneuvers were required before recovery was possible?

Alfisti's picture

I certainly don't think why the laser transmitters should not be the same system for both torps and sensor drones and, depending on how large the actual laser package itself is, adding additional ones to the hull should not be too much of an issue.

As you noted though, the drones are probably the more valuable asset so, if the ship was going to shoot with a drone constellation deployed (might need to look at whether that is actually a good idea or not when it comes time for building the first ops manual), the drones would probably need to take priority. That said, it would certainly be wise to carry spare and replacement drones, even if just to allow for the occasional loss/maintainence down time. As to how many though... that will ultimately come down to how small the drone body can be made and how much hull volume can be freed up to accomodate them.