The Ground Handling Blog

Mototok's blog for Hangar Professionals

Written by Mototok on August 5, 2022 // 12:00 AM

Using AGVs in Engine MRO Centers


Over the past few years, we have closely monitored the building manpower crisis. We knew this would be a global issue and talked about it over three years ago.

The global pandemic did not help; airlines shut down and parked their fleets, and an aviation career, whether on the maintenance side or flight operations side, looked less secure and profitable for the rank novice off the street. These were terrible optics for an industry already looking at more of its workforce leaving annually than had replacements coming in.

Plenty has been written about the technician shortage, and there is no end. What we must do in the MRO industry is learn to do more with less using the tools at our disposal. Technical advances in software and machinery allow us to pick up the slack of a depleted workforce by employing software solutions and automated machinery in ways that have never been possible.

The Engine MRO Facility

Our focus today is on engine MRO centers. Modern high bypass turbofan engines are huge; take the General Electric GE90-series of engines that power the enormous Boeing 777. The GE90-115B has a diameter of 128 inches. That’s ten and a half feet! The dry weight on these engines is around four tons bare, and quite a bit more with all the accessories attached.

With the cradle and engine combined, the total weight for an engine could be easily in the five to six ton range, maybe more.

In rebuilding or repairing, the wires must be dollied around the MRO, including from station to station. With dry weights like these, you aren’t doing that by hand.

An MRO facility is the most ideal location for deploying automated guided vehicle (AGV) technology. MROs are built entirely around processes; there is a specific pattern and flow to everything you do in them. Deviations are not made on the fly. The engine will progress from one location to the next in a specific pattern and order.

MRO maintenance is a different animal than line maintenance. Line maintenance focuses on taking a jet with some sort of breakage and returning it to airworthy condition in the short duration before, between, or after flights.

MROs are built around processes with little deviation. The engine begins at point A, proceeds to point B on a designated date, and so on. All engines proceed in the same order, so a common path is easy to establish from one point to the next. Our AGVs are the ideal solution for this type of operation. By applying stripes and command barcodes through the path, your engines will be safely and automatically moved from one position to the next and follow the exact same route with extreme precision (~3 mm accuracy).

Antiquated Equipment

Most engine facilities have used the same old equipment for many years. And why not? These tugs, whether diesel, gas, or propane/natural gas, have served admirably. It is, after all, a simple task.

The tug hooks up to the engine cradle and moves it from one point to the next.

So why change it?

Because these are outdated. For one thing, there is the issue of fumes. You have to open the shop whenever a tug is going to operate to air it out, which can get uncomfortable in extreme environments. Listen, nobody wants to open up the shop in Chicago in January or in Tulsa in August. Doing this is also costly.

But more than anything, it ties up valuable man hours in a task that can be automated. Manpower is the most valuable commodity in the MRO trade and is the hardest to replace. Why would you tie up a technician with 40 years of experience in engine repair for 30 minutes to tug an engine around when you can automate that process entirely?

You just bought 30 minutes of manpower back by allowing technology to do a menial, low-skill job. We don’t say this to belittle your workers or their skills; to the contrary, we understand how irreplaceable their skills are and how underutilized their skillset is when they have to put their tools down to move an engine.

Internal combustion tugs are also higher maintenance than our electric tugs. Our electric tugs are sealed units and require little to no maintenance. You just plug them in, and they take care of the rest. You won’t get that with a traditional tug. You will have downtime with these. They need the oil changed, tires replaced, and standard maintenance inspections and checks.  

Modern Solutions

It is 2022. We cannot build technicians faster or coerce them to join the aircraft maintenance trades, but we can build AGVs that make your processes easier and maybe even better.

Automated Guided Vehicles

So, what exactly are AGVs?

AGVs have been used in warehouses and manufacturing for a long time.

They take any vehicle that can be retrofitted with an optics package and guidance and place them where optical cues can be used. AGVs follow specific paths defined by a stripe on the floor.

The great thing about using AGVs in a facility like a warehouse or a maintenance facility is that once the path is measured and laid on the floor, the AGV will never deviate from it. This means that you can program your AGV into and around very tight quarters, which it will execute time after time.

AGV employs a barcode on the ground that gives it instructions, so you know that it will stop exactly where you need it to stop every single time. Every tug driver is a little different, and some technicians never get good at the task. They might miss the centerline two out of three times. The Mototok AGV never misses the mark, and the airplane or whatever it is towing always ends up in the exact same spot.

Synchronized Units

This feature doesn’t necessarily apply to an engine MRO, but it is an important enough feature to talk about since MROs sometimes do a lot of different tasks.

Our AGVs can be synchronized to work in tandem (or more) for large items. For instance, a fuselage can be cradled on a pair of AGVs, which lets it be moved in much tighter quarters than a single unit towing a fuselage cradle.

Erasing Human Error

The single most common factor in maintenance-induced failure comes from human error. Machines are highly reliable, and their breakage and failures can often be predicted. Human error is unpredictable.

Almost every incident involving an aircraft striking another aircraft or obstacle, whether under its own power or being towed by a tug, results from human error. The apron and airport markings are made to keep aircraft at specified distances from each other, so it almost always comes back to human error. The aircraft wasn’t parked correctly, or taxi lanes weren’t being observed.

An AGV cannot deviate. It simply follows instructions. As long as the course and the barcode instructions are placed accurately along the route, it will never deviate. It will stop where it is told to stop and turn where it is told to turn.  

Fully Automated Commands Process

All of the commands are automated. Once it is queued to perform a task, it simply does the task. Once the task is complete, it either moves on to the next or remains in place.

The AGV will only do what you tell it to do, nothing more and nothing less.

Your engine MRO will hum like it never has before because your assets will work like never before. You will not have to worry about a worker running off course and damaging an engine or your facility.

Great for Fuselage Maintenance, Too!

Our AGVs are capable of moving aircraft into and around facilities. If your MRO is set up with specific locations and routes common to every check, an AGV is a great solution to automate the process.

Your aircraft will safely and securely be moved from one position to the next without tying up a tow team. If your tow team comprises five members, you could save upward of 2 ½ man hours for a single, short tow.

Whatever your application is, our AGVs are designed to take the burden off of your team so they can focus on more important things: repairing aircraft. Whether an engine MRO shop, a full-service MRO center handling scheduled checks or even an aircraft manufacturing facility, our AGVs can be programmed to provide the best results. There is no telling how much longer and deeper the current technician manpower crisis will go, but we offer solutions that allow your technicians to focus on the aircraft instead of simple movements best handled by our AGVs.

Is your organization suffering from a depleted workforce? Call us to see what our remote-control tugs and AGVs can do for you!

Service Request  


Not sure if this tug fits your specific aircraft?
Let’s have a look!

We will get back to you within one business day. (Probably quicker, we’re German.)