Inspector 3.0 Improves Paper Mill Tank Inspection by Pinpointing the Location of Rust and Pitting

An inspector tested Flyability's software Inspector 3.0 during a paper mill tank inspection and found that it helped pinpoint the location of rust, pitting, and other defects within the tank.

Benefits in a nutshell


$960,000 Euros saved by reducing the downtime required for the inspection with the Elios 2.

Data Localization

Inspector 3.0 allowed the inspector to create a sparse point cloud showing the specific location of rust, pitting, and other defects within the asset.

Reduced downtime

Time needed for the paper mill tank inspection was reduced from four days to just six hours using the Elios 2.



Markus Rockenschaub is the managing director and founder of AEROVISION Drone Support GmbH, a drone inspection services company based in Austria that specializes in indoor inspections.

In his work, Rockenschaub regularly uses Flyability’s Elios 2 to collect visual data inside assets for his clients.


The first big mission he ever conducted with the Elios 2 was at a paper mill, where the owners wanted to test an indoor drone for a visual inspection inside one of the large tanks it uses to make paper.

Despite initial skepticism at the mill, that first inspection was so successful that the owners hired AEROVISION  to conduct its tank inspections by drone afterward.

Rockenschaub has now been working for the plant for over a year. 

When Flyability announced the release of a new software called Inspector 3.0, which was designed to help inspectors pinpoint the location of defects in the data they collect with the Elios 2, he already had a tank inspection scheduled at the mill so he decided to test the new software there.

Below we cover the first tank inspection Rockenschaub did at the paper mill with the Elios 2, which took place over a year ago. After that, we cover the improvements he saw using Inspector 3.0 for a recent inspection of the same tank.

First Tank Inspection at the Paper Mill

Paper mills use huge industrial tanks to make paper—the tank Rockenschaub was first hired to inspect is 82 feet (25 meters) high and almost 33 feet (10 meters) wide.

Mill owners regularly inspect the surfaces inside these tanks, looking for damage to the welds such as rust, scratching, or pitting that might have developed since the last inspection.

These inspections are not mandated by law, but are done to ensure that the tanks stay in good condition to avoid the costs of unexpected downtimes.

Typically, a paper mill tank inspection is conducted by an inspector entering the tank and collecting visual data directly. This approach requires the plant to build scaffolding inside the tank so that inspectors can see every part of it up close. 

But building and taking down scaffolding is expensive and time consuming, and can extend the downtime needed for the tank inspection by as much as two extra days.

Every hour the tank is down costs the mill $20,000 Euros. If the owners could use an indoor drone to collect visual data inside the tank, they could potentially save a lot of money by eliminating the downtime needed for building scaffolding.


A picture taken inside the paper mill tank by the Elios 2

To test this approach, the mill hired Markus Rockenschaub to use the Elios 2 to inspect one of its tanks.

Testing the elios 2

The tank Rockenschaub inspected at the mill is used to recycle old paper by mixing it with water as part of the paper-creation process.

To conduct the inspection, he worked with a welding expert who was a specialist in these kinds of tanks. As Rockenschaub flew inside the tank, the specialist looked at the drone’s video feed on a large screen, identifying potential defects and other areas of interest.

paper mill tank-2

Preparing for an inspection at the tank with the Elios 2

After the mission, the specialist reported that he was able to see everything he needed for his inspection work just as well as if he had actually been standing inside the tank.

Using the Elios 2, Rockenschaub was able to fly inside the paper mill tank and identify:

  • Scratches and pitting on its surface, which indicated that some of the surface needed to be renewed.
  • Rust on the surface of the tank’s roof.
  • Rust and heavy damage to the pillars of the roof.
  • Damage to welds inside the tank.

Benefits from Using the Elios 2

Here are the benefits the mill realized by using the Elios 2 for the tank inspection:

  • Savings. $960,000 Euros were saved by reducing the downtime required for the inspection by two full days.
  • High quality data. The images and video the Elios 2 captured were of such high quality that they completely replaced the need for direct visual data collection inside the tank.
  • Reduced downtime. The overall time required for the inspection was reduced from five  days (2 days building scaffolding, one day inspection, 2 days remove scaffolding) to six hours.

The first test was so successful that the mill hired Rockenschaub to conduct its tank inspections going forward, permanently changing how it conducted these kinds of inspections.

Testing Inspector 3.0 at the Paper Mill

A year after that first inspection flight, Rockenschaub wanted to test Flyabilty’s new Inspector 3.0 software at the paper mill to see if it could help improve the tank inspection process even further.

paper mill tank-circle

Inspector 3.0 allows inspectors to pinpoint the location of defects they identify in visual footage within a sparse point cloud of the asset they’re inspecting. This localization data can then be shared with other members of the maintenance team, so they can know exactly where defects are located within an asset.

[Related read: The Importance of Data Localization in the Inspection Business—And How Inspector 3.0 Can Help]

Using Inspector 3.0, Rockenschaub found that he could take the data collected with the Elios 2 and show the specific location of a defect within the paper mill tank. This locational data was coupled with visuals of the defect within the software (see example below), helping the paper mill’s maintenance team better understand the work that might need to be performed.

“Inspector 3.0 answers the question, ‘Where am I inside this asset?’ so I can visually see where a defect is instead of trying to imagine the location. It’s a huge benefit for inspectors.”

- Markus Rockenschaub, Managing Director and Founder of AEROVISION

Here are some pictures showing the point cloud and images Rockenschaub created with data collected by the Elios 2 and processed with Inspector 3.0 during the paper mill tank inspection:

paper mill tank-3

paper mill tank-9

paper mill tank-5


Rockenschaub plans to make Inspector 3.0 a regular part of his inspection work at the paper mill going forward. 

Using its data localization feature, he can provide his clients with specific locational data to help improve their maintenance procedures for the tanks they use in making paper.

He also plans to use the software with other clients, and to continue testing it to find ideal use cases where it can help provide key insights into exactly where defects are located, so they can be quickly fixed.



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