NEW Adventure Module!

[mmartin798]

Originally Posted by Gelrir

So we're to expect a team will search the entire island with a metal detector, and whenever they get a signal they'll dig at least five feet down? They'll be doing a lot of digging!

There may not be that much digging. The use of magentometers mounted on aircraft is used to scan for ferrous metals quite regularly. These aircraft mounted sensors can detect metal deposits 1000m underground with some pretty fine resolution, easily for the detection of a door.

The magnetic sensor is not well defined in either 3rd or 4th edition. But the description fits fairly well with the airborne sensors I have researched. The only difference would be the way it is mounted. In the air, the sensor is either a unit suspended under a rotary wing aircraft or on a stinger-like boom off the tail of a fixed wing aircraft. If the sensor were mounted to a metal vehicle, then it would be safe to say the rules description of a dead zone would be quite fit. I would think the dead zone would be closer to the 15m in 3rd edition rather than the 1m in 4th edition.

So to find this base, they just drive around and have the autonav marking the detected deposits and depths. Then look for the one that seems the most like an underground base, go to what looks like a hatch candidate and then start digging. What happens to the group as they drive all over the island is a different matter.

Note: I don't have this module, so I am just basing this on the information in this thread.

[Gelrir]

Originally Posted by mmartin798

There may not be that much digging. The use of magentometers mounted on aircraft is used to scan for ferrous metals quite regularly. These aircraft mounted sensors can detect metal deposits 1000m underground with some pretty fine resolution, easily for the detection of a door.

Hmm, if that's the range and resolution of a MAD boom, then finding any underground structure (let alone the door) will be trivial ... just a few passes over or near the island should be enough (especially if you know or suspect it's on the coast). The island is about 200 square kilometers in area, but much of it is only 5 kilometers wide. I wonder how the magnetic detector "indicates" information ...

--
Michael B.

[mmartin798]

Here are a couple PDFs for your consideration on airborne magnetometer surveys:

https://www.geosci-instrum-method-da...5-181-2016.pdf

https://www.geosoft.com/media/upload...vey_Reeves.pdf

If there are enough other ferrous minerals in the area, that may help mask the location, but a solid steel door should still show if you take more passes closer together.

[Gelrir]

Very interesting stuff!

"The airframes of modern aircraft are primarily constructed from aluminium alloys which are non-magnetic; the main potential magnetic sources are the engines. As a first approach, then, magnetometer sensors have always been mounted as far away as possible from the aircraft engines."

In an armored car the whole vehicle is a magnetic source, alas.

"Permanent magnetisation of the aircraft which will be unchanging unless engines are changed or magnetic objects (such as toolboxes) are brought on board."

Not sure how the Project avoids that. Careful with re-arranging your machine guns!

Finding the base itself (which has thousands of tons of rebar and structural steel) will make finding the actual entrance much easier. Keep in mind that whatever capabilities you describe for the Project magnetic sensor will be brought up again by your teams!

--
Michael B.

[mmartin798]

Originally Posted by Gelrir

Keep in mind that whatever capabilities you describe for the Project magnetic sensor will be brought up again by your teams!

I have been giving this some additional thought. To work, the magnetometer would have to be some kind of standoff distance from the team's vehicle. Going with something a kin to the fixed wing aircraft solution, the sensor could be mounted on a collapsible 3-4m pole that attaches to the body of vehicle, giving a final height of 4-5m above ground level. Driving with the sensor up would limit their speed and the types of terrain they could drive in. This does not stop them from doing measurements in rough areas, as they could go there with the sensor down, stop the vehicle, raise the mast, take the measurement, lower the mast, drive to the next location in the search grid and repeat. It would take probably 1-2 minutes to raise the mast, 1-2 minutes for the sensor to stabilize and take the measurement, another 1-2 minutes to lower and secure the mast with about 1 minute for general chaos running around the vehicle. So about 12 measurements per hour not counting travel time in rough terrain. There is still the 15m diameter blind spot directly below the mast caused by the large ferrous mass constantly there. This might be a suitable compromise for making the base a bit more difficult to find.

[Desert Mariner]

I don't have the module so am not party to all of the details of available equipment, etc. But I do work for an engineering consulting company that conducts this type of survey for civil and archeology applications.

There are other options for this type of survey (this includes magnetic, GPR and LIDAR). For those difficult to access areas, we've used a mountain bike. More recently, the use of drones has saved massive amounts of time and money for surveys.

[Ash247]

Venting shouldn't be that much of a problem, Morrow normally just use Nitrogen to store their bases. So to make it breathable you just have to add Oxygen to make a 80(nitrogen)/20(oxygen) mix