Suunto Hel02 Review
by James Thornton-Allan
Suunto have released a new dive computer called the Hel02 which is marketed to challenge the advanced technical diving computer market. With multiple gas mixes and the ability to handle normoxic trimix, this computer has the window sticker to tempt any diver.
However, all that glitters is not gold and you only have to look at the history of a company to realize that adding more features to a computer isn’t a good thing.
Traditionally technical divers would dive using a depth gauge and timer combined with a slate. This method isn’t the most flexible but it does create disciplined divers. I personally prefer to dive trimix on a slate, it keeps me alert and ensures I dive the plan rather than just jumping in and watching reserves.
This new computer has many features that allow divers to go quite deep with a real sense of freedom. Many remember the total collapse of their “bling tech” computer, the D9. It was ordered by the U.S consumer safety council to be recalled because it was giving false decompression times. For the original review of this product refer to: “Dangerous at Any Depth”
The more dangerous aspect of the HelO2 is its complexity in function, especially for people who already own the Vytec DS computer, . This is also Suunto’s first computer where you can reduce the conservatism. However Suunto state this feature is only recommended for fit and young individuals. How many people place themselves in this category I wonder?
The HelO2 computer was loaned to us for testing to see if it was something we would be happy to recommend to our customers. After signing a liability release for Suunto, assuring them we would also use a back up source of decompression information, we strapped on the Helo2 and jumped in.
One major problem with the Hel02 is that it still does not show your upcoming stops. It has a “time to surface” indicator which estimates your schedule providing you swap on the gases you have programed, but that’s not the same thing as actually knowing what your stops are. With such advanced display, the computer should be able to show a graph or a forecast of stops and depths. I think this has to do with their forecasting style of diving. Those who have been on a Suunto before would of seen their computer go into decompression mode which just disappears sometimes when they arrive at a shallower depth around 10m. The Hel02 computer does the same thing, we got 3 minutes of deco, stayed over our depth for 2 minutes and it just went back to no decompression diving at 10m.
One of our instructors took the Hel02 for a recreational dive to test it for himself, as he was planning on upgrading from his Vytec Ds. Disapointinngly the instructor felt the Hel02 lacked important features and had he been on a trimix dive he would of bailed to slate and a back up.
One of the other aspects of the computer is the decompression model it uses. The model is called the Suunto Technical RGBM algorithm, despite not fully implementing the RGBM bubble model. Dr Bruce Wienke, who developed the full RGBM model, also developed the Suunto Technical RGBM algorithm and describes it as a simulation of a bubble model. When dived alongside a VR3, which uses a traditional Buhlmann model with Pyle Stops, the decompression required was almost identical. It is clear from the profiles produced by the HelO2 and from the new version of the Suunto Dive Planner that it is primarily a Haldanean/Buhlmann model with deep stops added.
The HelO2 was also compared against tables generated by two bubble models, VPM (using V-Planner) and RGBM (using GAP). It was clear that the profile required by the Suunto Technical RGM was very different to the RGBM profile generated by GAP. However the X1, which uses VPM-Live, matched the V-Planner generated VPM tables almost exactly. This is further confirmation that the HelO2 does not use a full RGBM implementation.
Post testing my conclusions are that Suunto have achieved what they set out to achieve. They have produced a computer which is easy to use and will appeal to a large number of Trimix divers. They have managed to do this at a price point that I think will appeal to a great deal of people coming into technical diving. Although it has its limitations, I can see this computer becoming a huge success, primarily because of distribution and getting your hands on this computer will be very easy compared to others. The HelO2 will polarize many in the technical diving world, with some people loving it and some people hating it. This will probably be the same people on the fence about the DSAT vs TDI debate as well.
However after several dives and debates with regards to its performance with other technical diving professionals, I would not recommend this computer at this time. Perhaps upon future releases of the HelO2 when all the potential bugs are fixed I will give it a second consideration. In the end, everyone recommends a VR3 (the closest competitor), despite the price, which will be the least of your concerns when diving beyond 100m
*this computer was tested againts the Vytec DS, VR3, Pursuit, and Uwatec Depth and Timer.