The Rotax 916 iS, the One Hundred Sixty Horsepower Turbo That Runs on Car Gas and Flies With a Single Lever

The Rotax 916 iS is a 160-horsepower turbocharged, fuel-injected aircraft engine that eliminates the traditional mixture and propeller controls, letting the pilot manage power with a single lever. Built by Rotax, a division of Bombardier Recreational Products (BRP) in Gunskirchen, Austria, it holds sea-level power to roughly 15,000 feet and is designed to run on both 100LL avgas and premium unleaded automotive fuel (mogas). It trades the mechanical simplicity of legacy engines for computer-managed efficiency, turbocharging, and readiness for an unleaded-fuel future.

What Is the Rotax 916 iS?

If your mental picture of a Rotax is a small, buzzy engine on a light-sport trainer, that picture is about a decade out of date.

For years, the flagship was the Rotax 912, a 100-horsepower four-cylinder that sipped fuel and spun a small propeller fast through a gearbox. It trained a lot of pilots, but 100 horsepower runs out of runway when a manufacturer wants to build a bigger, faster, four-seat airplane.

So Rotax climbed the ladder. The 915 iS arrived with around 140 horsepower and a turbocharger. Then, at the Aero Friedrichshafen show in Europe in 2023, Rotax unveiled the top of that ladder: the 916 iS.

The headline numbers: 160 horsepower for takeoff for up to five minutes, and about 137 horsepower maximum continuous, all from a four-cylinder engine with a dry weight in the neighborhood of 185 to 190 pounds depending on equipment.

How Does the Rotax 916 iS Make So Much Power for Its Weight?

Here is what most people miss. A carbureted Lycoming making that same 160 horsepower - the kind bolted to trainers for half a century - weighs meaningfully more once you count everything hanging off it. The Rotax makes Lycoming power at a real weight savings.

That power comes from turbocharging and intercooling. The turbo takes exhaust gas that would otherwise leave as noise and heat, spins a turbine, and crams more air into the cylinders. The intercooler then cools that compressed air back down, because hot air is thin air, and thin air makes less power. A cool, dense charge means more oxygen per stroke and more power.

The cylinders are a hybrid design: the barrels are air-cooled, and the heads are liquid-cooled. That means the engine carries a coolant system - radiator, hoses, and pump - which a typical legacy aircraft engine does not have.

In an airplane, every pound you don’t spend on the engine comes back as fuel, payload, or climb. That’s why power-to-weight matters more than it looks.

Why Does the Rotax 916 iS Only Need One Lever?

The 916 iS uses electronically managed fuel injection with two independent engine control units - what Rotax calls a dual redundant system. Think of it as two small computers, each capable of running the engine by itself, constantly reading air, fuel, throttle position, pressure, and temperature, and metering everything to keep the engine in its ideal zone.

That is what gives you the single lever. There is no mixture knob. The computer sets the mixture thousands of times a second, better than any hand could. Climb, and the air thins out - you touch nothing, because the engine already knew. Descend into thick air, same story. The pilot’s job of leaning the engine simply disappears into software.

This isn’t only about convenience. A large share of piston-engine trouble comes from a human mismanaging fuel and air: carburetor ice, fouled plugs from running too rich, a cooked cylinder from running too lean on a hot climb, or forgetting the mixture on a high-elevation go-around. Take the human out of that specific loop, and a whole category of mistakes goes away. That is the real safety argument for electronic engine management.

How Does the Turbocharger Change Flying at Altitude?

A normally aspirated engine loses power as it climbs. Every thousand feet, there is less air, so there is less power, and the climb rate sags until the airplane won’t go up anymore. Anyone who has flown a hot day out of a mountain airport has felt it.

A turbocharged engine fights that. The 916 iS holds its rated power well into the mid-teens, with Rotax quoting sea-level power maintained up to around 15,000 feet.

That means an airplane that climbs like a champ off the runway still climbs like a champ at 10,000 feet, where a normally aspirated airplane of the same horsepower is gasping. For mountain flying, or for getting on top of weather and winds, that is a genuinely different airplane.

Can the Rotax 916 iS Really Run on Car Gas?

Yes. The 916 iS is happy on 100 low-lead avgas, but it is also designed to run on premium unleaded automotive fuel (mogas) - roughly the same fuel from the pump down the street, as long as it meets the spec and doesn’t carry too much ethanol.

This matters right now because the entire piston fleet is living under a countdown. Leaded avgas is on its way out, and the industry is working through an uncertain, anxious transition to unleaded. An engine designed from the start to burn unleaded fuel isn’t waiting for that transition - it already lives on the other side of it.

Fuel burn is also low. Because the computer meters so precisely and the engine spins efficiently, these Rotax engines drink noticeably less per hour than older designs making similar power. Over a long cross-country, that means dollars and range.

What Are the Trade-Offs and Downsides?

Every advantage carries a cost. Here are the honest ones.

It’s a geared engine. The fast-spinning engine turns a gearbox that steps speed down to something a propeller can use. It’s beautiful engineering, but it has its own maintenance, inspections, and service life. A direct-drive Lycoming or Continental bolts the prop straight to the crankshaft, and that simplicity has kept those engines flying for seventy years.

It uses liquid cooling. Coolant means a radiator, hoses, a pump, and fluid to check and change - plumbing that can leak and fittings that can fail. Air cooling has the enormous virtue of mostly not being there. Rotax went liquid on the heads to run hotter, cleaner, and more efficiently, but that’s added complexity, and complexity carries a maintenance bill.

It needs electricity. The two engine control units and the fuel injection require power. Rotax builds in redundancy - dual computers, dual circuits, backup provisions - precisely because a dead engine computer is a dead engine. But this is not the airplane that keeps running with a totally dead electrical system the way an old magneto-fired, carbureted engine will. The design answer is redundancy rather than simplicity, and you should understand which philosophy you’re buying.

Price and ecosystem. This is a premium engine, and installed in a new airplane it represents real money. Because it’s newer, the mechanic on your field who has rebuilt Lycomings his whole career may not have deep Rotax time. That is changing fast as Rotax builds out training, but it isn’t yet universal. In a remote area, ask who works on these before you buy one.

Time in service. Traditional engines have millions of hours and decades of hard-won failure knowledge. The 912 and 915 family the 916 is built on has an excellent, proven track record, which is reassuring - but the 916 iS specifically is still building its own hours in the field. New is exciting, and new is also new.

Which Airplanes Use the Rotax 916 iS?

The engine is showing up first where power-to-weight matters most: clean-sheet designs and modern composite airframes.

The Sling High Wing out of South Africa was built around it. Tecnam, the Italian manufacturer, has put it on the nose of their aircraft. Bristell and a number of others in the light and experimental world have embraced it. It’s the natural top engine for the category of modern four-seat composite airplanes that are too heavy for 100 horsepower but don’t want the weight of a big six-cylinder.

This isn’t vaporware. The 916 iS is certified, shipping, and flying on real airplanes you can put a deposit on today. Where it’s still growing is penetration into fully type-certificated aircraft, where the certified world moves slowly and deliberately - but every year brings more airframes offering it and more shops that know it.

Two Philosophies of the Airplane Engine

The 916 iS is ultimately a story about two competing philosophies.

One philosophy says an engine should be simple, dumb, and nearly indestructible: air-cooled, direct-drive, mechanical, magnetos, and a mixture knob you control by hand. Fewer parts, fewer computers, and if the electrical system dies, it keeps running on the fuel in the float bowl. That philosophy built modern aviation, and it is not wrong.

The other philosophy says let the machine manage itself: put a computer in charge of fuel and air, use a turbo to erase the altitude penalty, use liquid cooling to run clean and efficient, spin fast and gear it down for power-to-weight, and burn the unleaded fuel of the future. Accept more complexity in exchange for a smarter, more efficient, easier-to-fly engine - and answer that complexity with redundancy instead of simplicity.

The 916 iS is a strong argument for that second philosophy. It isn’t the right answer for every airplane or every mission. But if you’re looking at a new airplane with a single power lever where the mixture and prop controls used to be, one that holds full power past 10,000 feet and runs on fuel that will still be sold in twenty years, now you know exactly what you’re looking at - and what it cost the engineers to give it to you. There is no free horsepower. There is only which trade you decided to make.

Key Takeaways

• The Rotax 916 iS produces 160 hp for takeoff (up to 5 minutes) and about 137 hp continuous from a four-cylinder weighing roughly 185–190 lb dry.
• Its turbocharger maintains sea-level power up to about 15,000 feet, transforming climb performance at altitude compared to normally aspirated engines.
• Dual redundant engine computers and fuel injection enable single-lever operation, eliminating the mixture control and a whole category of pilot fuel-management errors.
• It runs on both 100LL avgas and premium unleaded mogas, making it ready for aviation’s transition away from leaded fuel.
• The trade-offs are real: a gearbox, liquid cooling, dependence on electrical power, a premium price, and a shorter in-service track record than legacy Lycoming and Continental engines.