Wherrytown mine, Penzance

The Wherrytown mine has it all: A man who died twice, an underwater mine entrance, a stocks and shares scandal, and modern day diamond drill prospecting. The Cornwall and Isles of Scilly Maritime Archeology Society wanted to take advantage of the rarest of low tides in February & March 2023 to help them capture a 3D map of the Wherrytown mine in Penzance. They also needed some aerial video for their presentations and promotional materials.

The flights were conducted over two visits, exactly a month apart. 

There were a number of tricky problems to solve for the client. Firstly, many amatuer geologists were also going to be climbing over the rocks at the same time and so a small (sub 250g) drone was needed in order to capture the necessary data whilst staying within the required separation distances. However, because the sensor on sub 250g drones is smaller than on larger models, two visits were needed to get enough data for the 3D software to produce a detailed enough output for the client's needs.

Next, almost the whole of the bay in Penzance falls into the Flight Restriction Zone (FRZ) of the heliport which operates regular flights to the Scilly Isles. This meant our contacting the Air Traffic Control (ATC) well in advance of the planned flights and providing them with flight plans, risk assessments, and proof of pilot competency and proof of commercial insurance. Once all of the pre-flight documentation had been supplied, our team stayed in regular contact with the ATC throughout the operations. Anyone looking to fly drones in the area covered by the FRZ should apply via this link and ideally give around two weeks notice. The team at the Penzance Heliport were very professional and helpful, and we couldn't have done it without their help, so a big shout-out to them.

Once all the data had been captured, the images were processed, a 'wireframe' generated, and then the images were 'draped' over the frame to create a 3D model, in this case using Agisoft Metashape software. Cornwall Drone Services were able to tailor the second flight to ensure that any 'gaps' in the data from the first flight were filled in on the second flight. 

Maps like this are very useful for archeologists, not just because they can be used to good effect in presentations and funding applications, buit also because the accuracy allows accurate and detailed measurements to be made from the model directly rather than having to wade out into sea over slippery rocks and seaweed!