Inspiration Ultralight

Inspiration ‘Ultralight’
By Gabriele Paparo


IMPORTANT This article is not an invitation to modify/ change any components in your diving equipment in particular in your rebreather set; any variation could be very dangerous and will break the warranty condition of the product.


As you know I am a rebreather diver, I use to dive different units (SCR – CCR) but mostly my Classic & Vision rebreather. I am really happy so far with these units. I decided to modify minor things of their design, in order to better fit their features to my needs, of course no modifications were done to the safety features of the unit.

Some variations were done to the harness (I use a steel plate with SMB container, rigid D rings, no fastex – DIR style harness, scooter strap), the BCD inflator was also modified with a shorter one without AutoAir feature. Certainly the most severe modification are the ones related to the breathing loop. For instance, the Y-piece from Delta P in order to add a forth oxygen sensor or (when is my intention to use it) the possibility to switch from the normal mouthpiece to an AGA FFM with integrated bail-out regulator (see my previous article about it). These modifications are very important because they are done to vital parts of the system (the breathing loop) so it is important to do not underestimate it. Minor changes on the rebreather’s pneumatics were done, none of vital parts were modified though.

The last modification – talking about time – that I felt had to be done was related to weight/ volume features of my rebreather and it was related to the long range transportation characteristics of the unit (in particular flying with the rebreather avoiding security problems and very expensive charges).

After 9/11 events security measures are very rigid and the price for overweight luggage is very expensive. Therefore, you are going to find a hard time in flying with cylinders (even if empty) and sofnolime (security tends to recognise it as an lethal NBC weapon!). In the summer 2003, during a trip to Scapa Flow archipelago (Scotland) I was forced to spend a night in Birmingham (UK) while the security was checking all my luggage (I was travelling at that time with my original Classic box and the complete unit inside it). Coming back from Florida, one year later, I had to pay $220 for the 30lb overweight of my scuba diving equipment.

The final motivation to modify my unit in this way were some articles about the better features of the Megalodon rebreather vs. the Inspiration about easy transportation… I wanted to demonstrate that an Inspo could also be easy transportable … if you choose to loose some very important features of the cover.

In my opinion the modifications that I am going to introduce are going to be very useful in certain circumstances (basically travelling by plane to do OW dives) but they have also the other side of the coin (no cover – no protection – dangerous in overhead environment or while scootering).


Inspiration Ultralight


The 3 goals of my modifications where essentially:

• Remove all the optional parts that are not going to be essentially to safely dive the rebreather
• Allow the rebreather to fit any cylinders, no matter about dimension/ size/ valve’s design and more
• Obtain a low weight/ low volume unit in order to fit a standard trolley and to save money during airplane travel

I was very happy at the end of my work because each goal was reached and, in addition, some secondary features where obtained from the Ultralight design:

• The unit is extremely streamlined, very easy to swim even in strong current – very very low drag;
• All the parts are exposed… a continuous bubble check is made from the dive buddy during the dive; very easy to find a malfunction
• Extremely easy to rinse it up in all its parts

Physical Description

The modifications I have done, even though they are major changes, did not influence my ability to easily return to the original Classic configuration free from the use of special tools but for a couple of allen wrenches.

Of course the Ultralight unit could be equipped with standard Inspiration cylinders or any different type (from 1lt up to 10lt cylinders). For instance, you could dive the Ultralight with 2 x 7lt/ 50cf on the side (to keep a good posture and trim) and a small Oxygen cylinder on the bottom; in this case you carry your bail-out gas on the back (air as diluent and a spare 7lt for decompression gas) and no additional bailout cylinder hanging on the front is required; thousands of different ways are allowed to the diver….

Basically, the Ultralight is a standard technical diving plate (in my case I have got a low weight/ very robust carbon fibre one, made from Dive System) where you fix all the Inspiration vital components plus the harness and the BCD.


I worked on the carbon fibre plate in order to make holes (very easy to work with fibre) to fix the straps for cylinders and canister. The canister is held in place by a strap that also keeps the BC (a classic wing style made from Dive System in a Kevlar fibre), 2 additional straps, one on each side, provide a solid retention system for any size cylinders. Underneath them runs the LP hoses from the second stages that feed the ADV and solenoid valve. The LP hoses for the diluent & oxygen bypass and run on the side of the diver, therefore are much shorter then the original ones.


On my Ultralight I decided to use different first stages: to do this it is imperative to fit the intermediate pressure as recommended from the factory (9.2-9.5 for diluent side/ 8.0 for oxygen side). Of course an overpressure valve is required for both first stages as well as a complete oxygen cleaning for at least one of the 2 first stages.


Why switch to different first stages?! Well… there are 2 reasons basically:

• First of all I decided to use low weight alloy regulators (aluminium or titanium) in order to keep all the system very light.
• Secondly, I decided to keep all the components of the standard configurations in diving order: all the parts are still in place in my Yellow box (regulators, hoses, manifold, gauges, and so on) so it is easy enough to re-fix the counterlungs and put back in the canister and you are ready to dive your standard Classic/ Vision unit!

In this way it is extremely easy and fast to switch from Standard to Ultralight configuration…

This solution is not expensive if you think that the first stages that I use in my Ultralight are simply the ones that I normally use for my bailout OC bottles; since I am not bringing with me the “murphy’s” bottles I can bring just the first stages and use them inside the Ultralight.

So, to have a better idea, the parts that are NOT present anymore on my Ultralight are:

• Yellow Box
• Gas manifold
• Diluent SPG (if you need one you can easy find it in the dive centre)

This saves about 5Kg/10lb!


The parts that were replaced to lighter/different ones are:

• Harness (carbon fibre, very light)
• BCD (very small and light)
• Oxygen SPG (shorter hose)

This saves about 2kg/4lb!

The parts that you are not required to carry travelling are:

• Oxygen cylinder
• Diluent cylinder

This saves about 10kg/21lb!

At the end, the total weight before boarding is about 17kg/ 35lb less, in comparison with the standard Classic/ Vision unit (with cylinders); of course, if you are SURE to find standard Inspiration cylinders at the local dive centre you could save up to 10kg/ 20lb just leaving the cylinders…. but you still have to travel with pretty big luggage in comparison with the Ultralight design.

Once you get to the dive site, the task is to find an oxygen cylinder (any size but provided with 200bar Din adaptor), a diluent cylinder (or you can also consider using normal air coming from your side-mounted bail-out cylinder), chemicals and any missing SPG (oxygen cleaned in case of use for oxygen cylinder).

Personally I prefer to keep in place the Y-piece from DeltaP; I think it is not going to save more weight, so I prefer to keep the feature of the fourth oxygen cell. Much better would be to leave at home the heavy VR3 computer, especially if you dive a Vision with Nitrox/ Trimix integrated software.


Final Comments

So finally we can enjoy our Vision/ Classic rebreather even in far places just paying one time what you should pay everytime you want to fly with your complete set…. If you travel often,… it probably worth!

In my opinion though this configuration is not better than the standard for some reason (that’s why I do not keep diving the Ultralight version).

I think the cover on the Inspiration and on every other rebreather is an important feature; first it allows you to really easy set up the unit or dis-assemble it after the dive (in the Ultralight you need some more minutes). Second, even though the complete cover increases a bit of drag it provides very important protection to all the important (and delicate) components; hoses, electronic lid and more are covered by the “yellow box”… it is easy to understand how important this cover is looking at the scratches on a used cover. This is even more important in the case of overhead environment dives or during scootering, when the diver could hit obstacles at high speed providing major damages while diving. These are some of the reasons why I still prefer fully covered CCRs instead of Megalodon/ Kiss style rebreathers. Of course….pure personal opinion…!


Comments on Real Experience: Diving Hawaii

It was a long time since I knew that in a special occasion like my honeymoon I would reach some very far, beautiful and…. near-the-ocean area! We just had to decide which one…
In the meantime wedding planning went through…as well as dive equipment preparation and test dives in the Med sea and in the lakes.

Finally the big day came and we are in the airport to check in on an USAirways flight to California. Just 2 bags: one with garments and the other one with all my scuba diving equipment.

The content of the biggest bag is not just all my scuba diving equipment but also a complete Vision rebreather; I’m going to be honest telling you that I was pretty scared when the officer put it on the weight meter: it was almost 60lb (too much to fly); I remembered that inside where also some external items (for instance the Italian espresso coffee maker, I can’t travel without it!) and a few other things: after they were removed the weight was 54lb, enough to fly on the plane without any further problem and without any additional fees!


This is a list of the equipment included in my bag:

• Tech fins & mask
• Neoprene dry suit with gloves and shoes
• Dry suit underwear
• Surface marker buoy with spool
• Aladdin dive computer
• Oxygen regulator with hoses and SPG
• Diluent regulator with hoses
• Complete Vision rebreather
• Carbon fibre plate with harness, D rings, SMB pocket

The satisfaction I obtained diving my Ultralight was worth the time I spent to prepare all the details of the configuration. Now the rebreather will return to his standard configuration….waiting for the next trip!


Gabriele Paparo

Discuss this article HERE

IMPORTANT This article is not an invitation to modify/ change any components in your diving equipment in particular in your rebreather set; any variation could be very dangerous and will brake the warranty condition of the product.