Helicopter Engines

Following on from the concept developed in the 70SZ-H, the latest 37SZ-H brings a new level of performance to '30-class' helicopters.

Just about everything has been changed compared to the 32SX-H in the pursuit of power and control. That super-rigid crankcase contains a highly developed, ringed piston/liner set and optimised crankshaft for the right combination of power and smoothness. The new carburettor has been purpose designed for precision control and is capable of being operated by push-pull linkages if required.

The best '50-class' engine on the market just became amazing with the introduction of the new 50SX-H Hyper.
That CNC machined cylinder head has been developed to give better power and improved cooling at the same time. The new carburettor has also been improved to help extract more power than the standard engine without sacrificing the throttle precision you have come to expect from OS helicopter engines.
This truly is the 'best' engine in the 50-class and is fast becoming the best seller as well. It's an OS, what else would you expect!!

The max 50SX-H Hyper has established an enviable reputation for power, reliability and ease of use. The Max 55HZ Hyper moves that to a whole new level!

Designed primarily with the demands of the 3D pilot in mind, the 55HZ Hyper delivers 61 size performance in a 46 size crankcase. That power comes from the extensive experience that OS has gained over many years and working extensively with the worlds top pilots to refine all aspects of the engine without compromise in any area.

The letest engine in the 600/50 helicopter class borrows much of its technology from the fabulous Max 91HZ-R, to provide class leading power under the most demanding of 3D manouevres.

The latest DRS system (Demand Regulator System) uses a crankcase pressure tap-off to pressurise the fuel tank via a one way valve. The pressurised fuel is then carfully regulated at the carburettor to provide the optimum mixture no matter what demands are placed on it. This is done by using the negative pressure in the carburettor venturi as part of the regulation system.

A pump equiped engine designed primarily for the 3D flight and dramatic aerobatic manouevres.. Compared to the old 'Hyper' the new 91HZ-PS offers improved hovering stability as well as power at high speed to meet the further sophisticated 3D competition manouevres

Based on the multi-time FAI world champion 91HZ heli engines, O.S. is taking their new 91HZ-R to even higher levels of performance; thanks to the new "on demand" regulator system. Designed specifically for this engine, this system guarantees the steady fuel supply, needed for the most-demanding of 3D flights with constant, vigorous attitude and throttle changes. The 91HZ-R also performs well as an F3C powerhouse providing a steady, smooth run and exacting mixture controls.

Following the popularity of the 91HZ-R with On-Demand Regulator, O.S. has now taken high-performance, high-speed helicopter engines to the next stage of evolution. Introducing the 91HZ-R Speed Engines - based on the 91HZ-R, factory-tuned at the O.S./Japan facilities and guaranteed to blow you away!

For pilots who prefer aggressive, stick-bashing 3D flight competition, O.S. offers a 3D version

Following the popularity of the 91HZ-R with On-Demand Regulator, O.S. has now taken high-performance, high-speed helicopter engines to the next stage of evolution. Introducing the 91HZ-R Speed Engines - based on the 91HZ-R, factory-tuned at the O.S./Japan facilities and guaranteed to blow you away!

For pilots who prefer aggressive, stick-bashing 3D flight competition, O.S. offers a 3D version

The biggest, pure helicopter engine that OS have ever made delivers the levels of torque and power demanded by top fliers for both '3D' and sport applications.

The 15% increase in capacity offers a big increase over the .91 class engines yet still fits in mounts designed for that class. Modification to the cooling shroud is also unlikely.

The distinctive 'blue anodised' cylinder head distinguishes the 105HZ engines from the 91HZ series yet retains the HZ series styling overall.

General internal design is very similar to the 91HZ series and draws on OS's deep experience in creating the best helicopter engines for all classes.

Like the 91HZ-R 3D, the new 105HZ-R utilises the OS 'DRS' fuel delivery system to cope with the extreme manouevres of modern 3D flight

Identical to the regular 105HZ-R technically but supplied with the latest Powerboost 105 pipe. The pipe has been purpose designed to suit the 105HZ-R and will provide high power and torque across the RPM range without heat build up caused by restriction of gas flow.