A derelict port crane in Cork had been sitting unused for years and our client needed it decommissioned - but before anyone could approach it with a removal plan, they needed to know exactly what they were dealing with. The condition of the structure was genuinely unknown and, given the obvious deterioration visible from a distance, putting people close to it was considered too risky without a proper assessment first. Engineers With Drones were called in to carry out that assessment using a high optical zoom inspection drone.
This is what the job looked like using drone technology.
What the job would have looked like if drones were not used.
The crane was located at the end of a jetty in Cork - relatively modest in size compared to the large ship-to-shore container cranes at modern port facilities, but a structure that had been left exposed to the elements for years with no maintenance. Size is not what determines the hazard in that situation.
The client's concern was straightforward: the structure looked bad, and sending people in close without knowing the full picture was not acceptable. They needed that picture - a detailed, reliable understanding of the current condition of the crane - before they could safely plan the decommissioning work.
As Bob Foley, founder of Engineers With Drones, put it: "They were concerned that putting people close to the crane as it stood when we inspected it could be dangerous so they decided to utilize a drone to get an idea of what they were dealing with before they ever approached it with the idea of removing it."
A detailed drone inspection of a derelict port crane in Cork, carried out ahead of a planned decommissioning. The inspection produced a full defect report, classified by severity to allow the client to plan a safe approach and removal strategy.
Jetty end location, close to water, requiring full PPE including life jackets.
From arrival on site to data capture complete. All imagery verified on site before sign-off.
The full inspection report, annotated imagery and defect classifications delivered to the client within 48 hours of fieldwork.
A complete Risk Assessment and Method Statement was prepared and agreed with the client before any fieldwork commenced.
Images below feature a selection of drone crane inspection projects carried out by Engineers With Drones.
The key piece of drone technology for a job like this is the high optical zoom camera. This is a high-resolution sensor - at least 20 megapixels, in this case potentially up to 40 - paired with a long focal length lens, around 120mm, which translates to roughly 7x optical zoom in practical terms.
"That allows you to keep the drone away from the structure while still getting very high resolution imagery," Bob explains. That matters a great deal when the structure you are inspecting is in an unknown structural state. You do not want the drone close to something that might shed material or partially collapse.
From a safe operating distance, the team was able to get detailed imagery of cable terminations, corroded fasteners, structural members, pivot points, and the condition of guard rails - all the critical elements of the crane that needed to be understood before any human approach.
Context is everything in an inspection report. Showing a sheared bolt or a corroded joint in isolation tells you very little - you need to know exactly where it sits in the structure and what role it plays. Every image in the report was annotated and positioned relative to a structural diagram of the crane, so the client could immediately understand the significance of each finding.
The inspection covered all primary and secondary structural elements. The findings were classified by severity, with critical defects clearly flagged. Here is a summary of the major findings.
The drone was able to get right in to cable terminations and fork connections, clearly showing the corrosion level on the cable strands. On the underside faces there was biological growth present. On the upper faces the cables appeared cleaner but were still heavily corroded throughout.
The primary pivot point for the jib is one of the most structurally significant components on the crane. The supporting structure around this pivot was found to be heavily corroded, with some elements close to corroding completely through. This was flagged as a critical finding.
Flat horizontal surfaces had retained water over a long period. This caused significantly heavier corrosion on those horizontal faces compared to the vertical surfaces nearby. Several secondary structural members were found to be nearly corroded completely through. These were classified as critical level defects due to the falling object risk they presented.
As Bob notes: "Some of these could be four or five hundred kilos of weight, steel beams, things like that. So you don't want that coming down." The presence of the drone, operating remotely, meant that none of the inspection team were exposed to that risk during the assessment.
Perhaps the starkest finding in the report concerned the guard rails. These are the rails that any person climbing the crane would have relied on to prevent a fall. They were found to be entirely gone as a functional steel component. "This is what used to be a steel member is now almost entirely just corrosion. There is no core material left at all. It's just completely gone. It's all just iron oxide and nothing else."
To put it plainly: anybody who would have approached this crane and assumed the guard rails were safe had no idea of the actual condition of the structure. The drone inspection removed that uncertainty entirely.
There is a tendency to assume that taking something apart is less hazardous than operating something that is defective. In reality, decommissioning a structure in this condition is a skilled and genuinely dangerous operation. The people who do this work professionally know exactly how to cut, dismantle and lower structures like this without endangering themselves or anyone nearby. They are not using spanners and checking torques - they are using oxygen lances and cutting equipment, and the approach is entirely different.
Knowing the condition of the crane in detail - where the worst corrosion was, which components were at risk of sudden failure, where safe angles of approach existed - was exactly what allowed those specialists to do their job safely. That is what the report gave them.
A lot of people assume the dangerous part of mountain climbing is going up. It's actually coming down is far more dangerous. Like this, putting stuff together, you're much more cautious because it's a new object. Somebody comes in here and they just start hitting it with a sledgehammer - but there's far more danger in that.
"The primary thing that they gained from this particular report was knowledge of safety, knowledge of the structure as it stands right now and knowledge and insight on how they could go about decommissioning the crane."
With a full picture of the crane's condition, our client was able to identify the safe angles of approach, understand the specific hazards on the structure and hand that information over to the decommissioning team. Work that previously would have meant sending people in blind - or relying on binoculars from a distance - was now informed by detailed, classified, annotated imagery of every significant element of the crane.
Beyond the immediate safety benefit, the decommissioning also opened up the jetty again. With the unsafe crane structure safely removed, that area of the terminal could be brought back into use for vessels.
Fieldwork time: approximately two hours on site. Report in the client's hands: within 48 hours.
You can find out more about our industrial inspections or our marine and port inspections. Alternatively you can contact us here.
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