Simple and Strong Aircraft


The K-Max owes its performance to the Flettner double-rotor principle. It allows heavy loads to be transported with relatively low engine power. Thanks to the counter-rotating main rotors, the K-Max does not need a tail rotor; this saves weight and drive power.


The counter-meshing two-blade rotors are fixedly synchronized at 90 degrees via the main gear. The rotor blades are controlled using the Flettner flap on the rear edge of each blade. The control forces remain low, and there is no need for hydraulic assistance as on traditional helicopters.


The aluminum half-shell fuselage is just wide enough to accommodate the pilot as well as the engine with transmission


54 Sept/Oct 2024


and fuel tank. The narrow shape ensures strong stability of the cell, especially for a better absorption of forces. Thanks to the simplicity of the construction, the empty mass remains low. Additionally, in the narrow fuselage, the pilot has a direct view of the external load from both sides of the cockpit. An armrest and a support on the fuselage ensure a comfortable seating position for the pilot during flights with loads, and this increases precision.


The first flight of the K-Max took place in 1991, and no major modifications have been made to the machine since production began; its construction is still solid today. However, the safety of the helicopter could be improved by strengthening the freewheel clutch, which sometimes caused problems in the early years. For the future, the manufacturer has promised further improvement of the rotor blades.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84