OPERATIONAL EXPERIENCES WITH THE KOLIBRIE RAMJET HELICOPTER

Last year a small number of Netherlands Helicopter Industrie (NHI) Kolibrie ramjet helicopters were operated in Europe. Because this was the first time helicopters of this type were used by civil operators, it may be of general interest to discuss some of the experiences obtained during these operations. Right at the start of the Kolibrie design, it was realized that this ramjet helicopter could be used advantageously as an agricultural tool, where ruggedness and simplicity are very important factors. Realizing that every operator would have his own opinion as to how to equip the helicopter, it was decided to design a fuselage that would consist of a very simple frame with ample room and means to attach any equipment (see Figure 1). Some accessory equipment has been developed by NHI and can be obtained optionally. This concept proved to be right because operators immediately started to adapt their own special equipment to the Kolibrie frame. Figure 2 shows a selection of the configurations that, except for the litters, has been used in actual civil operations. The helicopter is shown in all cases in front view. Configuration A represents the "minimum helicopter" with one tank, one seat, and no windscreen. In this condition, the maximum useful load can be carried. The addition of a windscreen is favored by most pilots, but on at least one special occasion it was removed as will be shown later. Agricultural flights were made with one seat. There were occasions, however, where a second seat was installed. In one instance, the second seat was used by a forest ranger who had to point out to the pilot which trees needed to be sprayed.