Gluhareff Pressure Jet Engine
A Jet You Can Build From Plans

The dream of personal flight goes back to Icarus, the mythical character who made wings of wax and feathers, then soared too close to the sun. Today the vision is lived out in modern form with machines such as flying platforms, rocket propulsion backpacks, and fixed-wing ultralight aircraft. But the idea of a VTOL machine - a personal helicopter - holds a special fascination for those of us who are smitten.
         When Eugene M. Gluhareff examined the technical challenges of personal flight from his perspective as a helicopter design engineer, it quickly became obvious that the absence of a suitable blade-tip powerplant was the missing ingredient. So he designed his own powerplant specifically for this type of application. Today's pressure jet engine is the result of some 30 years of refinement. And you can build the engine yourself following the step-by-step instructions in our comprehensive plans package.
         The Gluhareff Pressure Jet engine is a remarkably simple device made of thin-wall stainless steel tubing and sheet metal. Inside, it contains only a length of coiled steel tubing (the fuel line), which gasifies and super-heats the incoming liquid propane before it is injected at supersonic speed at the top of the intake stack. The engine has no moving parts, yet it is fully throttleable. Thrust is controlled by opening or closing a valve in the propane supply line. To start the engine, simply open the fuel valve then press a button to send current to a small spark plug mounted at the rear of the combustion chamber. After a 10-15 second warm-up to stabilize the flame front, the engine is ready for full-throttle operation. To stop the engine, simply turn off the fuel supply.
         One of the most remarkable aspects of the engine is that it works at all. Prior to Mr. Gluhareff's design, engineers had understood that it was possible to produce thrust by using the energy of pressurized propane to induce the fuel/air mixture. Calculations, however, indicated a maximum thrust of only about 3 to 5 pounds, and extremely high specific fuel consumption (fuel consumed per unit of power output). The secret to the success of the Gluhareff Pressure Jet is its sonically tuned intake stack, which results in far greater thrust and far lower specific fuel consumption.
         Three intake stages are sized according to the length of the sound waves produced when the engine is running. The sound waves acting against the intake stack translate into a pumping action that pressurizes the incoming fuel/air mixture. This pressurizing action is similar in effect to that of the turbine in a turbojet engine. If the intakes are not in tune, the small 20-lb thrust engine, for example, produces only about 3-5 pounds of thrust. The fish-mouth cut at the rear of the tailpipe also has sonic effects. It reduces noise and increases thrust. 
         Building the jet requires some sheet metal forming, but much of it can be assembled from stock materials. For example, the exhaust pipe, combustion chamber, and fuel lines are cut from thin-wall stainless steel tubing.  The intake stages, the diffuser skirt that blends the final intake stage into the combustion chamber, and the transition piece between the combustion chamber and the exhaust pipe are hand formed. You can spin the nose cone on an ordinary home workshop woodworking lathe, or purchase it ready-made from the source listed in the plans. By doing the fabricating and welding yourself, total building costs can be held to little more than the cost of the sheet metal, tubing, and fittings.

Specifications

         Eugene M. Gluhareff was a graduate Aeronautical Engineer from the Rensselaer Polytechnic Institute in Troy, New York. He was a key figure in the history of the helicopter almost from its inception, working directly under Igor I. Sikorsky and side-by-side with Igor A. Sikorsky, Chief of Aeronautics at Sikorsky Aircraft Corp.
         In addition to producing many conventional helicopter designs, he also pioneered the single-bladed rotor system, and invented the Kerosene Fueled Valveless Pulse Jet engine, which was used to power the world's first single-bladed one-man helicopter (of his design). Later he developed a Delta-Wing Convertiplane for the USAF, which utilized a foldable single-blade rotor with a blade-tip cold-jet power system. He was Project Engineer on the Top Sergeant pulse-jet powered helicopter, and developed the XH-26 one-man tip jet powered helicopter for the USAF.
         In the early 1960's, Mr. Gluhareff developed rotary wing drones for the U.S. Navy. After joining Douglas Aircraft Co. in 1963, he worked as Design Engineer Scientist on the Saturn Rocket and was in charge of the sequence of events from firing to parking orbit on subsequent launchings. Following the Saturn program, he became Specialist in the design of Rocket Stabilization Systems for ejection seats and space capsules.
         In 1972, he established EMG Engineering in Gardena, California, where he continued the development of the propane-fueled pressure jet engine featured here. Building this remarkable jet engine is a fulfilling and inexpensive way of owning an important piece of aviation history.

         Our plan-set is based on Mr. Gluhareff's original drawings, technical documents, hand-written construction notes, and photographs. Theoretical information in the manual was taken from the Technical Handbook provided by Mr. Gluhareff with the GTS-15 Teaching Stand, which was used by universities to teach the principles of jet engine operation. The step-by-step construction procedures in the technical manual were derived from Mr. Gluhareff's professional notes and drawings on the various procedures used to hand-build engines in his workshop.   Photographs in the manual showing the engine at various stages of construction were scanned from original photos taken in Mr. Gluhareff's workshop for internal documentation purposes.  Until now, these construction procedures and photographs have never been published.  
         Although the textual material has been slightly edited and the original illustrations have been recreated on computer, great care was taken to insure that the new material is an accurate replication of the original work. This plan-set is the only authorized and updated work available of Mr. Gluhareff's original material. Click for a detailed description of the plan-set.

EMG-300 Helicopter


The EMG-300 helicopter was the last project developed by Mr. Gluhareff. This helicopter was specifically designed around the G8-2 jet, and was first test-piloted by Eugene M. Gluhareff. Click on the image for details.