Dear Editor,
In response to some of the letter-writers in the Chronicle who have written about the Bell 206 helicopter, the facts are that a newly acquired aircraft which costs the Guyana people millions was sitting in the Tacama savannahs and the cause of its malfunction is still being investigated. Secondly this particular helicopter was used as a crop-dusting aircraft for many years and it operated under registration JA-1686.
However, it is perfectly possible to change the role of most aircraft; you simply reconfigure it to suit the appropriate mission. So it is possible for a “crop-duster helicopter” (this does not exist by the way, it is simply fitted with crop-dusting attachments) to be converted to a medical evacuation aircraft.
Now to say that the only way for a turbine engine to suffer damage is if the manufacturer’s recommended temperatures are exceeded, is not true.
There are many variables involved in the starting of a turbine engine. Maybe the aircraft had inherent issues which led to it being damaged significantly. The Guyana Defence Force has been operating rotorcraft since 1975, and there has never been an instance of any engine being damaged due to pilot error or any starting anomaly.
This is testimony to the fact that the GDF has great aviators and they are very well trained. In addition, Allison engines are very pilot friendly. Allison is now owned by Rolls Royce and their engines are very strong and built to withstand mistakes made by pilots during start sequences. Garrett engines are, however, for the truly experienced professional and are not forgiving if an aviator makes an error during any start-up.
I am an aircraft engineer with in excess of 20 years of experience on many different types of engines and airframes. The bottom line is that the human element does not always control the starting of a turbine engine. You may have scenarios where there is a ‘run away’ starter, a malfunctioning fuel control unit, or an erroneous indication from the gauges you rely on to make split-second decisions during start sequences. There are numerous other things that a pilot cannot control and it may be too late once the problem is discovered, or he may not be able to stop the problem. He may try, but if you have a poorly maintained aircraft or an aircraft that has sat for 10 years before it was flown to Guyana, then who knows what else is still wrong with the aircraft
The conclusion by some that the Bell 206 is a favourite and preferred helicopter is ancient at best. It was a favourite, it was preferred, but over the years it has proved itself to being less and less useful. It is only used in reconnaissance as an observation platform and for initial pilot training. That’s it. Militaries, special forces and policing agencies around the world have replaced their aircraft with larger ships like the Bell 427 or the Bell 412, or with Eurocopters. The Bell 206 was primarily used in the ’70s, ’80s and early ’90s. We are approaching 2009.
We are still awaiting the famous infra-red system and searchlights that are supposed to light up a football field as promised by the Guyana Defence Force. However, no country or operator of any aircraft is allowed to purchase an infra-red system unless approved by the US State Department. This transaction typically takes approximately 6-10 weeks for approval, if it is given. I assume that the GDF has applied for this permit since I know none of the helicopters has this equipment at present.
Yours faithfully,
Mark King
