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Oxygen measured as delivered

Portable product increases supplemental oxygen endurance

The earliest portable supplemental oxygen systems made with general aviation in mind pushed out this vital brain fuel at a steady rate, without regard to demand. Today’s pilots need not waste their supplemental oxygen during periods of low demand; there’s even an app for that.

Inventor, pilot, and Aithre Preident Jim Ruttler tested his app-controlled oxygen system at altitude. Photo courtesy of Aithre.

Aithre unveiled the AVI8 (also branded as Avi8, to clarify the mnemonic properties of this device’s name) at EAA AirVenture in Oshkosh, Wisconsin, and quickly encountered supply chain issues that delayed delivery. The company reported September 5 that a copper shortage had resolved, with additional tests and tweaking of the system meanwhile completed, including a three-hour cross-country flight cruising at 17,000 feet msl. Pilot and Aithre President Jim Ruttler flew with an older, larger oxygen system as a backup, but did not need to use it.

A pulse oximeter (sold separately) linked to an iOS device enabled the AVI8 to throttle oxygen delivery and maintain Ruttler’s blood oxygen saturation at or above 92 percent throughout the flight, the company reported. That critical indication of oxygenation (a useful proxy for pilot cognitive capacity) actually climbed with the aircraft established at that thinly oxygenated altitude, “demonstrating that the AVI8 was properly titrating the dosage of oxygen in real-time.”

Titration is facilitated by optical flow measurement of the oxygen as it is delivered to each connected cannula, an accurate means of calculating the precise volume of a gas flowing through a tube, and that feature is a first for portable supplemental oxygen products, the company said.

The AVI8 system, composed of a carbon fiber cannister that holds 152 liters of oxygen compressed to 2,000 psi that accounts for most of the system’s six-pound weight, delivers oxygen exactly as required, wasting hardly a molecule and increasing the system’s endurance beyond that of the largest available portable tanks with more traditional delivery systems—up to 12 hours of use time.

The AVI8 includes the cannister, the gas regulator, and a low-pressure delivery control system that links to the Aithre Connect iOS/WatchOS app, which provides basic controls and additional features such as the recently added emergency mode that pushes delivery through (up to two) nasal cannulas up to 12 liters per minute, useful when carbon monoxide in the cabin is competing with oxygen for slots in your circulatory system. This high flow is also dialed up automatically if carbon monoxide levels exceed 50 parts per million, or if the pilot’s oxygen saturation falls below 85 percent. It also kicks in automatically if the aircraft climbs into Class A airspace.

At lower altitudes, the system calculates demand and flow based on the data collected in real time by the connected Aithre Illyrian Smart Oximeter ($130 on the company website, and also available from various retailers). The AVI8 with two-place distribution system (cannulas, independent valves and controls) and carrying bag is priced at $1,395 on the company website. This system can be used in experimental aircraft without further approvals or paperwork, though it ships with an empty oxygen cannister while the company awaits a permit to ship the system with the first fill of oxygen included. A wireless pressure gauge is also included in the package.

A rubber mount with a hook-and-loop strap is also included, and the cannister can be mounted up to 15 feet from the cannulas. An optional plumbing kit for experimental aircraft includes a bulkhead fitting for baggage compartment mounting, and behind-the-panel plumbing.

The AVI8 oxygen delivery system uses optical flow measurements to monitor and regulate supplemental oxygen delivery, adding hours of endurance to the compact system. Photo courtesy of Aithre.
Jim Moore

Jim Moore

Editor-Web
Editor-Web Jim Moore joined AOPA in 2011 and is an instrument-rated private pilot, as well as a certificated remote pilot, who enjoys competition aerobatics and flying drones.
Topics: Gear, Aircraft Accessories

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