Reviews |GLADIUS Advanced Pro review

GLADIUS Advanced Pro review

GLADIUS Advanced Pro

GLADIUS Advanced Pro Snap Verdict

The GLADIUS Advanced Pro is one of the most exciting things that I’ve ever had arrive at the front door, and it’s dominated much of my spare time in the month I’ve been testing.

It’s essentially a drone, but it goes underwater rather than zipping through the air.

Unlike its airborne cousins, there are no real restrictions on use, except of course in a public swimming pool, maybe.

It’s just fun, revealing a world we would otherwise be unlikely to ever see.

The GLADIUS Advanced Pro is a four-part tale, the drone bit that connects to the Buoy and winder by cabel, then there’s the wireless bits in the form of the console like controller and mobile app. It all comes neatly packed inside two cleverly designed bags that can be worn as a backpack.

The set-up is quick with a quick ballast change, quite literally a weight, that bolts onto the drones underside, the choice of two is dependant on whether you’re in salt or fresh water. Each ballast is clearly marked.

Connect the app and wires, and off you go – it’s all quite straightforward and incredibly easy to use.

What’s more, the battery life is incredible at around three hours.

OK so you need water to use it, but if you’re into water sports or want to explore the sea/river bed without getting wet this drone is ideal. In fact, as with its air bourne cousins, there’s amazing potential for its use.

Drone | | £1949

For GLADIUS Advanced Pro

  • Easy to set-up
  • Good for both salt and fresh water
  • Excellent video quality

Against GLADIUS Advanced Pro

  • Controller not to the same standard as the drone
  • Pros can get tangeled in weed
  • Takes practice to orientate

I live half an hour away from the sea and in a place that’s abundant with rivers and streams. Even now under one of the hottest summers, I’m pleased to say most of the rivers are still relatively full and now nicely warm. Even the sea is bearable and accessible without a wetsuit to protect against the cold.

This has made testing the GLADIUS Advanced Pro exceptionally easy and a great summer distraction enabling me more time to experiment and explore the area I live, and from an entirely new perspective.

As an underwater drone, one of the first questions I had was how on earth do the radio signals penetrate the water. Well, they don’t, let me explain.

The GLADIUS Advanced Pro consists of the drone which is connected by cable to the buoy, this, in turn, connects wirelessly to the controller and app.

The app and controller enable you to control the GLADIUS in much the same way as any other drone.

You get a live feed from the camera, but there is a big difference in as far as you can’t really see the drone once it’s submerged. So navigation has to be done by watching the live feed or the direction of the bright yellow cable as it moves across the surface of the water.

Really this is all about the underwater camera, not just the drone bit, and like the impressive aerial footage that has made drones so popular, in an equal measure the GLADIUS captures incredible quality footage from the deep.

Maybe because the underwater drone is something totally new to me it appealed so much, but I’m sure it’s something more. The GLADIUS Advanced Pro is by no means perfect, but I can already see it’s potential in the professional market as well as for me, just owning one for fun.


Looking at the camera side of things and the GLADIUS Advanced Pro features a 4K camera. This offers 4k at 30fps, and the option to drop the resolution down to 1080p and film at 30, 60 or 120fps if you do want to capture some fast-paced action.

GLADIUS Advanced Pro

This footage is captured at an impressive maximum code flow of 60mb/s to ensure excellent quality capture. As well as video the camera is also capable of taking still images at 12mp, and the switch between shooting modes can be made quickly through the mobile app.

All video is captured in mp4 and stills as JPEG, ensuring maximum compatibility. This footage is stored on the internal 64GB memory. Footage can then be download through the app.

The camera features a 1/2.3-inch sensor and is fronted by the f/2.8 aperture lens. This has a focal distance range of between 70mm to infinity which is fine as long as you don’t face plant the drone into the seabed. The FOV is 95º.

A nice touch is the addition of a 49mm filter thread on the front hood of the lens which enables you to attach filters to counteract the colour temperature difference when using the drone at depth.

Shooting underwater usually requires plenty of light, and the sensor enables a decent sensitivity range of between ISO 100-3200.

To help shed light on your underwater exploits, there are two powerful LEDs, one on either side of the camera. These offer 1200Lm of light with a colour temperature of 6200k. Through the app, there’s also the ability to dim the lights depending on the conditions.

The drone is designed to be operated from the land, and the tethered cable that connects the drone to the buoy is 100m in length. This either enables you to launch the drone 100m away from you or if you’re on a platform then you could dive the drone to a depth of 100m.

More likely the 100m cable will give you a good amount of flexibility when it comes to exploring your location.

As well as the cables 100m length you also have the strength of the WiFi signal between the controller and the buoy. This is 100m which is a good useful distance if you’re following the drone along a river bank.

One of the most significant differences between the GLADIUS Advanced Pro and it’s airborne cousins, aside from the air-water thing, is the usage times. As drone pilots, we’re used to an average of between 15-20mins, although this is rising. Here with the underwater drone, you’re looking at about 3 hours at 50% power.

The drone features four motors, two at the back and two vertical through the body of the drone. These enable the maximum drone manoeuvrability in the water. They’re also powerful enough to push the drone at 4 knots at maximum power.

Buoyancy in the sea and fresh water is entirely different and to enable the GLADIUS Advanced Pro to stay neutral in its environment it comes with two different ballasts.

These are marked for sea or fresh water and simply screw directly onto the underside of the drone.

As ever with drones, the app plays a big part in the use of the GLADIUS Advanced Pro. The app enables the connection to the controller and drone to manoeuvre the craft in the water, start and stop recording, adjust settings and even broadcast live webcasts.

As well as the primary hardware the GLADIUS Advanced Pro arrives with a backpack for the drone and separate case for the buoy. This makes the drone easy to carry, and a nice design touch is the ability to clip the buoy bag onto the backpack.

The drone itself weighs in at 3.2kg and the buoy 1.3kg.

There are two versions of the underwater drone; GLADIUS Advanced Pro which will set you back £1949 and GLADIUS Standard Pro for £1599. The biggets differences between the two are the colour and the Advanced films in 4K.

In this test, we’ve looked at the GLADIUS Advanced Pro.

Build Quality & Handling

The GLADIUS Advanced Pro arrives in two boxes: one that contains the drone itself with all its gubbins, and the other that features the buoy.

GLADIUS Advanced Pro

The drone arrives in its own backpack and this is functional and simple in design. Having lugged the thing on my back over many miles in the last month, I can say with confidence that it’s comfortable enough for the first mile, bearable after the second and a relief to arrive at the destination by the third.

The actual quality of the backpack is excellent and made from high-quality materials that far exceed many dedicated camera bags I’ve tested in the past. The issue of comfort is merely down to the weight of the load over a long distance and an issue most bags would have.

There is a chest strap to help take some of the weight, but the addition of a waist strap would have been a comfortable addition.

The interior is well padded, and there are a few pockets for the chargers, cables and the controller.

The drone itself comes in an addition pull string bag, this helps to keep the main interior of the backpack clean after you’ve used the drone.

The overall quality of the drone is excellent from the aerodynamic front through to the fin at the back.

The front is the most impressive part of the drone and supports the camera in the middle with the 49mm thread in case you want to add a filter. On either side of this camera are the two led lights which can be operated directly from the controller.

The front and main body of the drone are bright yellow, and all feels solid and robust, more like professional scientific equipment than a consumer drone.

Getting ready to launch

To get the drone ready for using it first needs a charge, the power cable slots into a port in the rear and a screw-in waterproof cap protects this.

On the top of the drone is the comlink where the cable from the buoy needs to be screwed into, again a very similar connection to the charging port at the back. This port is covered by a small rubber cap which is of course removed and replaced by the cable when it uses.

The only other area to set-up for the drone before launching is the ballast. This is held in place by two screws and takes a few seconds to unscrew and switch between either the seawater or freshwater option.

The buoy and cable winder

The second bag contains the buoy/cable winder. This is just one unit and the buoy and cable winder are not two separate items, just in case you were wondering.

The bag that the buoy arrives in, as mention, has been designed to clip onto the back of the backpack. Once in place, it enables you to easily transport everything you need to operate the drone in one easy package.

What I liked was the ability to remove the smaller bag after some distance so it could be carried to reduce the weight or preferably handed to someone else to carry.

The buoy itself looks impressive, and in the bag are two aerials that first need to be screwed into the body contacts.

Once done the loose end of the cable can then be screwed into the top of the drone before switching the whole thing on by pushing the metal switch.

A beep sounds just after pushing the button, and the lights on the buoy illuminate showing the status.

There’s nine LED’s in total that can be seen through the small plexiglass window. These show the main navigation light, WiFi link and a variety of power readings. I found a little crib sheet was useful so that I knew what each light meant.

The power is also shown on the app, so it’s not a big deal if you don’t have the key to what each of these lights means.

Game style controller

The final part of the system is the gamer style controller. Once you download and connect the app, it gives you full analogue control over the drone once in the water.

It’s designed with a spring loaded centre section which enables you to place your mobile device or tablet in the centre which is a great idea.

The controller has plenty of buttons, and many of these are not used, and I suppose are left free for programmable options in the future.

What is apparent from the outset is that the controller is not of the same quality as the rest of the drone. It feels a little bit cheap, and whereas the rest of the GLADIUS Advanced Pro is very obviously high quality, the controller is a little generic.

There are buttons on the controller that don’t do anything, and it does feel that it’s all a bit of an afterthought.

The controller is also not waterproof, but then it doesn’t need to be as neither is my phone. But, I have some confidence that my phone would survive a downpour of rain or a slight splash, whereas I wouldn’t be so hopeful for the controller.

In use, however, it does the job and enables direct interaction and control over the direction and control over the drone.

What starts to highlight the quality of the controller is the fact that you use it in combination with the app for phone or tablet.

The App design is solid with easy navigation and control and plenty of options. Its well thought out and well designed.


My first few ventures to water didn’t go quite to plan and for no real fault of the drone.

There are checklists that I have for when I fly drones, and I follow these before I fly. Even though this underwater drone is entirely different, those same, or at least very similar, checks should still be followed.

GLADIUS Advanced Pro

First and foremost is to check that the app and firmware all up to date. My first outing was hindered by needing to update the drone and app before it would launch. I’m sure there was a way around the update, but at the time I couldn’t for the life of me get it to work, so I was forced down the update route, and that took a good hour over a weak 3G signal.

Next was to ensure that I’d attached the right ballast. As I discovered it’s no use trying to bodge it using the freshwater ballast in the sea or the seawater one in fresh water, the result is a drone that doesn’t quite balance correctly.

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It’s easy enough to swap the ballast as long as you have a Phillips screwdriver, unfortunately in both situations I didn’t, my fault not the drones. It did, however, make me think that maybe a quick release mechanism would have been useful.

Finally, conditions; take a look at the water you’re about to launch into and see first if you can see the bottom or at the very least some clarity. If not then the camera, as with you, will see very little.

This means that when you come to watch the footage back later, you’ll see the odd glimpse of stone, weed and maybe a fish or two.

After these initial setbacks, I had at least learnt how to control the drone in a variety of different conditions and learnt plenty else along the way.

I’d also learnt that in some situations there was no other option than to get into the water and rescue the drone from reeds, rocks, gravel and a lack of control due to the wrong ballast being fitted.

Ultimately several runs through and the quality of the run and footage started to improve and truly showed this small drones potential.

The video quality underwater is fantastic, and with the addition of the two LEDs illuminating the path, there’s tonnes of potential.

As with any drone, there’s a learning period where you get to see how the craft operates and what it can and cannot do.

That journey with the GLADIUS Advanced Pro is short, and it doesn’t take you long to get to grips with the way that it works and how to control it as it dives towards the seabed.

The app is incredibly well designed and simple to use. Once you’re familiar with the control of the craft, it’s then over to the app which acts as a window through to the underwater world.

The app helps you gauge the navigation as well as filming, and as ever enables direct access to the camera settings such as resolution and framerate.

After a very short time and with the right conditions I had pretty much skilled the GLADIUS Advanced Pro.

Underwater handling

For anyone who has flown a drone, you’ll know about some of the complexities of turning a corner. You can tilt the drone left or right and that will get you going in the right direction but to turn it properly you need to learn to bank. 

Likewise, when it comes to the GLADIUS the controls are much the same as any other drone and it takes a while to get used to the control underwater. This issue is further compounded by the fact that you can’t actually see the drone bank, so much of the control is initially down to an educated guess. However, after a time you get used to doubling watching; one eye on the water and the other on the screen and all starts to fall into place. 

During use, I found the location could dramatically affect the way you use the drone. 

In the sea, once you get out of the shallows life is easy and diving the drone through the deep water all proves simple to control, there is always a slight but noticeable drag of the cable through the water but the small motors are powerful enough to override any drag or tilt that effects the drone too much. 

Used at the sea I found that I’d aim to send out the drone as far as possible and then dive and weave about. The line of direction for the drone was direct and the cable quickly unraveled from the spool with relative ease. 

Using the drone in rivers and freshwater, the cable did seem to have a far greater effect on the stability of the drone. Firstly it caused more drag, and after a few trips I found it was worth unraveling a good length of cable to lessen the effect of drag caused by the cable and spool. 

In freshwater and without the buoyancy of the salt water the controls were also a little more lively, and greater care needs to be taken to avoid crashing into the river bed in the shallower waters. Generally, an overall less full-powered approach was needed, or maybe just a little more skill.

As with any drone it takes time to master the controls in both salt and fresh water. As the results of a crash are generally far less destructive than when using an aerial drone it’s thankfully far shorter journey to skilling the control.

Video quality

When it comes to footage the clarity is excellent, with the large open lens on the front of the camera helping to capture the light.

The app gives plenty of options over the resolution and framerate, but for the duration of this test, I generally stuck to 4K.

Colour was good despite being submerged and the detail the camera was able to pick up even in the slightly murky world of the UK waterways and coast was still impressive.

Looking at the overall quality and the fine-tuning of the lens optics for underwater work give it a higher quality look and feel that you’d get from a GoPro or similar.

In lower light conditions the sensor was able to balance the exposures and although there is a sign of noise it’s incredibly well handled.

likewise, shifts in exposure are well controlled with the exposure shifting smoothly.


Absolutely amazing and as much fun as flying an aerial drone. It gives you the ability to film the world in a way that would otherwise be impossible, and it’s great to see the underwater world.

GLADIUS Advanced Pro

When we see sub aqua footage in programs on the TV, it looks spectacular and now with the GLADIUS we have the tool to film similar footage ourselves and in familiar locations.

It did take me a while to fully work out the controls of the drone and part of that learning process was to ensure that I followed regular checks.

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On a couple of occasions, the drone did become difficult to control, and this was always due to stones or reed getting caught in the propellers. Although this may not be an ideal solution, I felt the addition of a mesh over the props would help reduce this risk, but would inevitably reduce the power of the propellors.

Despite my adoration for the GLADIUS Advanced Pro by the end of the test, there were a few issues that I would like to see addressed, and these genuinely don’t even require any significant updates.

Firstly grills to cover the props to stop stones, reeds and seaweed being sucked in, then a quick release design for the removal and fitting of the ballasts, so I don’t need to remember to take a screwdriver and finally and most importantly a better controller.

Out in the open water

Once in open water rather than trying to navigate through reeds and seaweed the GLADIUS Advanced Pro performed incredibly well. It was responsive and fast to manoeuvre and although great fun to just pilot through the water there is, of course, the camera angle.

The camera worked flawlessly, firstly giving direct and instant feedback to the app for navigation and control and secondly for filming the underwater world.

The large lens on the front of the craft lets in plenty of light and the quality if the footage was excellent, as good, if not better than that from a submerged GoPro.

The GLADIUS Advanced Pro has taken me by surprise. I thought it would merely be a bit of fun, but it’s been so much more.

During my time using it, there’s no doubt that it pulls a crowd of inquisitive onlookers, and through it I have met those who are genuinely very interested.

Who were these people? Fishermen who just thought it was one of the greatest things they had ever seen. The ability to float this thing down the river and explore the river bed and fish.

Others were boat owners who loved the fact that they could throw anchor and then explore where they were, they also liked the fact they could check the underside of the boat quickly.

I loved it for its ability to give me a window into another world and a new opportunity to film something different.

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