There is a 1 litre measuring bottle sitting on a workbench at Base Aérienne 115 in Orange, southern France. It belongs to the maintenance team of Escadron Hélicoptère 01.065 Alpilles, the French Army helicopter squadron based there.
The bottle, marked in 0.1 litre increments, has lived on the bench for years. It does an important job. Technicians use it to measure small additions of turbine oil into the engines and gearboxes of their aircraft, somewhere between 0.1 and 0.5 litres at a time. The bottle is essential. It is also the source of a quiet problem in turbine oil contamination prevention.
The turbine oil can the squadron uses, a NYCO O-156 in military easy-open format, has a fully removable lid. When the lid is removed, the entire top of the can is open to the environment. Foreign object debris exposure is significantly higher than with a conventional sealed oil can. The oil sits open from the moment the can is opened until the moment it is poured.
Every time a fresh can of turbine oil is opened, the oil has to be transferred from the can into the measuring bottle so it can be measured. That transfer step, however careful, is a moment when contamination can enter the oil. The bottle then has to be relabelled with the oil type, batch number and expiry date, because regulations require traceability and the original can no longer holds the oil. And because the bottles inevitably get coated in oil during use, those labels never stay readable for long.
The result is a daily compromise. Accurate measurement at the cost of contamination control, traceability and time.
When the squadron approached us late last year, they were not looking for a sales pitch. They were looking for help solving an operational problem that, frankly, the FunnelCap in its current form does not fully solve.
How the FunnelCap addresses turbine oil contamination prevention
The FunnelCap was designed to remove the transfer step entirely. By fitting a closed dispensing system directly onto the original oil can, it allows oil to flow straight from the manufacturer’s container into the engine. No secondary bottle. No exposure to dust, debris or foreign object debris during the pour. The flexible hose reaches filler points that a traditional oil can cannot, which matters in tight engine compartments.
It addresses the two largest problems in helicopter maintenance oil handling: contamination at the point of transfer, and the loss of traceability when oil leaves its original container. The oil identification, batch number and expiry date remain on the original can, where they were printed at the factory.
For most operators, that is enough. For the French Army squadron, it was almost enough.
The one thing the current design does not solve
What the FunnelCap, as it currently exists, cannot do is measure 0.1 litre increments.
For an operator adding precise small quantities, that gap matters. The squadron had a clear use for the FunnelCap, but the moment they reached for the 0.1 litre measure, they were straight back to the transfer bottle. The contamination risk crept back in through the side door.
This is the kind of feedback you can only get from operators in the field. It is also the reason we listen.
What we are building now
The current development at TheCanKey, prompted directly by the conversation with Base Aérienne 115, is a FunnelCap with integrated 0.1 litre graduations on the dispensing chamber. The technician would be able to measure the exact quantity needed, see it added, and pour it straight from the original can into the engine. No transfer. No relabelling. No contamination exposure between the can and the aircraft.
It is a small design change with a large operational implication for turbine oil contamination prevention. It would eliminate the secondary bottle entirely.
We have the first prototype ready. The squadron has agreed to test it in service alongside their existing process, so we have a real evaluation under real conditions before the design is finalised.
Why this matters beyond one squadron
The challenge the French Army described is not unique to them. Helicopter operators across the world face the same constraint: small, frequent oil additions that need to be measured accurately, traced cleanly, and added without contamination. Whether the operator is a Bavarian air ambulance, a North Sea search and rescue unit, or a remote utility company in the Australian outback, the operational pattern is the same.
TheCanKey range is already used by more than 520 operators across 60 countries, including ADAC and DRF Luftrettung in Germany, the United States Coast Guard, the Icelandic Coast Guard, and the Royal Flying Doctor Service in Australia. The contamination challenges the FunnelCap addresses are recognised across the fleet.
Solving the 0.1 litre problem for one squadron is, in practice, solving it for hundreds.
What good operator feedback looks like
The most useful thing about the conversation with Base Aérienne 115 was that they did not stop at the problem. They described their actual process in detail, and where the FunnelCap fitted into it and where it did not. That kind of feedback is rare, and it is the only way a product gets genuinely better.
If you operate Airbus or other turbine helicopters and you are still using transfer bottles because you need to measure small oil additions, we would like to hear from you. The prototype is being tested. The next version of the FunnelCap is being designed around the operational reality your teams describe to us.
The 0.1 litre measuring bottle has done its job for a long time. We think it is time it retired.
