Last Word: Otch Otto


Super technology in a piece of string

While it might take forever to receive approval to install a radio in your helicopter, the most important piece of technology required for flying safely is completely unregulated.

About three years ago we bought a R35-million helicopter to deploy rapid response rangers with a tracker dog in pursuit of rhino poachers. To execute a ground-to­air operation. you have to be well trained, experienced and flexible. Speed and adaptation are essential success factors. all highly dependent on crisp reliable tactical radio communications.

Off-the-shelf helicopters are delivered with a radio equipped for air-to-air communication, so if you want to talk to the team in the bush you need to add a ground radio. However. any addition to an airframe must be approved by Statutory Aviation Authorities, the manufacturer. and your insurance underwriter.

This fitting can be done with a cable-tie and by mounting a small antenna to the bottom of the helicopter. An even simpler way to mount the antenna is to dangle 30cm of wire out of the side door, but that is rather silly.

The required radio fitment constitutes a major intervention in airframe performance and safety, and resulted in us using our helicopter without a mounted ground radio for a few years as we awaited approval. The creativity of the rangers resulted in a cab filled with handheld radios and cellphones, and creative hand signals to communicate with the rangers on the ground. One can only wonder what the approval process was to hang a nuclear device on a B25 in 1945. or the weight of the paper pile required to obtain approval for inflight refuelling. Your baby might even have matriculated by the time you receive approval to fit his baby chair to the helicopter.

A crucial part of keeping a helicopter in the air is completely unregulated. The senior field commander on a helicopter-assisted counter-poaching mission qualifies for the left front seat. He stares at a 10cm piece of string mounted on the centre window strut dangling in the wind in front of him during the ride from the base to the area of interception.

Whenever I walk past the front of the chopper. I am amazed by this 10cm piece of string or wool tied to a 20cm ‘official’ steel wire on the centre front window strut. I initially thought this out-of-place piece of fluff was part of the rag left behind by the window washer. This critical component actually serves as the slow speed crosswind or wind direction indicator. In flight, a string dangling 45 degrees to one side during a slow speed approach would indicate that the pilot should straighten out the string (using the joy stick and rudder) to point the loose tip of the string towards the windowpane. He is then facing into wind and can land.

It is unknown whether this string has statutory approval and whether the practise of knotting the tip, so it does not unravel at high speed, is prescribed or illegal. The knot obviously interferes with the angle of the dangle.

Nothing can replace this piece of string: nothing is more practical and reliable. The cheapest, simplest, most reliable and most efficient low-altitude, low-speed instrument technology in the helicopter aircraft industry is free! You can take one from grandma’s knitting basket!



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