Safety, costs, documentation quality and deployment scope – when the drone wins and when rope access (Seilzugang) remains the better choice. Operating since 2017.
The industrial climber with rope access technology (Seilzugangstechnik, SZT) is the established method of choice in many sectors for inspecting hard-to-reach structures: chimneys, silos, bridges, cooling towers, tall buildings. Qualified rope access specialists certified to IRATA Level 1–3 or the German FISAT standard can reach virtually any height and geometry while simultaneously examining, measuring and carrying out minor repairs.
However, rope access has structural limits that are increasingly problematic in industrial use:
An honest assessment must consider both sides. Industrial climbers have clear advantages in scenarios requiring physical contact:
The drone – depending on application either the ELIOS 3 for indoor use or the DJI Matrice 30T for outdoor structures – has clear advantages over rope access in several central dimensions:
The most fundamental advantage of drone inspection: no personnel are put at risk. During a drone deployment the entire team remains on the ground. This eliminates fall risk entirely – and relieves the operator of duty-of-care obligations towards height workers. With the ELIOS 3 for indoor use, personnel entry into confined spaces (Confined Spaces) is also avoided, which under DGUV Vorschrift 1 requires considerable safety overhead.
4K video footage, LiDAR 3D model and thermography combined deliver a documentation depth that no climber deployment achieves. All findings are three-dimensionally located, measurable and comparable over time. The 3D model can be imported into BIM/CAD systems.
For purely visual inspections the drone is generally cheaper. The comparison: a climber team (2–4 people) costs €1,500–3,000/day plus equipment hire, travel, safety gear. A drone team (1–2 people) is similarly priced – but more productive in the same time.
The following comparison shows for eight evaluation criteria which method leads. Rating: ++ (clear advantage), + (advantage), = (equal), − (disadvantage), −− (clear disadvantage).
| Criterion | Drone | Industrial Climber |
|---|---|---|
| Occupational safety (height / confined space) | ++ | − |
| Inspection speed | ++ | − |
| Documentation quality (video, 3D) | ++ | − |
| Visual resolution at close range | + | ++ |
| Tactile NDT testing (UT, MT, PT) | −− | ++ |
| Feasibility in poor weather | + | − |
| Cost per inspection object | ++ | − |
| Immediate repair after finding | −− | ++ |
The result is clear: for visual inspection and documentation the drone is superior in almost every dimension. For tactile testing methods and repairs the industrial climber remains indispensable.
Rope access remains indispensable for tactile NDT testing – but the drone defines the scope in advance.
The most practical answer to “drone or climber?” is usually: both – in the right order. Hybrid inspection combines the strengths of both methods:
This approach reduces the climber deployment to a minimum, saving time, cost and safety risk – without sacrificing the quality of tactile testing methods.
For purely visual condition documentation – the majority of all industrial inspection tasks – a climber is not necessary. Typical applications where the drone alone is sufficient:
Speak to us: we advise you free of charge on which combination makes sense for your specific equipment – and where we would recommend the climber.
We give you an honest assessment – including when rope access or a hybrid approach makes more sense.
Christian Engelke
Managing Director & Chief Pilot
Karsten Lehrke
Dipl.-Ing., Senior Inspector
Philipp
Drone Pilot & Inspector
Juliana
Project Coordination
Stephan
Drone Pilot & Inspector
For purely visual inspection and documentation the drone is in most cases the superior method. However, wherever tactile NDT testing (UT, MT, PT) is required, or where repairs must be carried out immediately after inspection, the climber remains indispensable. Our recommendation for complex assets: hybrid inspection – drone first, climber only in targeted, finding-based areas.
For visual inspection: yes, typically. A drone team (1–2 people) has similar daily rates to a climber team (2–4 people), but is 3–5 times more productive in the same time. The drone inspects 3–6 units per day; a climber team 1–2 structures. The cost advantage grows with the number of units and inspection height.
The ELIOS 3 for indoor use is completely weather-independent – it flies in tanks, boilers and confined spaces regardless of outdoor conditions. The DJI Matrice 30T for outdoor use is rated IP55 and is stable up to 15 m/s – considerably more weather-resistant than rope access teams, who must stop work at around 8–10 m/s (Beaufort 5).
For outdoor operations: EU drone licence A2/A3 (EU Drone Regulation 2019/945). For indoor inspections with the ELIOS 3: no drone licence required (EU regulation only covers outdoor airspace). Additionally: liability insurance (≥€5 million), and for VT reporting: VT Level 2 certification of the evaluating personnel according to DIN EN ISO 9712. We fulfil all requirements – operating since 2017.
Yes. The ELIOS 3 inspects chimney interiors from DN 600 upwards. LiDAR navigation works GPS-free inside the chimney. The lining condition, mortar condition, condensate zones and anchor bolts are documented in 4K. The DJI Matrice 30T covers the chimney exterior with 200x zoom from ground level – without scaffolding, without rope access.
The drone performs visual testing (VT) in 4K, thermography (TT) for heat anomalies and CUI detection, and 3D geometry measurement via LiDAR. It cannot perform contact-based methods such as UT (ultrasonic thickness measurement), MT (magnetic particle) or PT (dye penetrant). For these methods we recommend a hybrid approach: drone first for location, then NDT specialist for targeted measurement.
The key question: do I need purely visual documentation, or are tactile NDT measurements required? If purely visual: the drone is the better choice in almost all cases. If NDT measurements are needed: we recommend hybrid inspection – drone first to identify and prioritise, then NDT specialist only where needed. We advise you free of charge – simply describe your equipment.
You receive: 4K video of all inspected surfaces, a findings report (PDF) with photos, finding location, assessment and recommended action, optionally a LiDAR 3D model (.PLY/.OBJ) for BIM/CAD and thermography evaluation with radiometric data. This documentation depth is not achievable with rope access methods.
We help you decide which method is more efficient for your specific case – and combine both when it makes sense. Free initial assessment, no obligation.