Tuesday, December 20, 2005

Before you crack open that cold one...A sober note for the festive season from Hugo Meyer

At this time of year parties are abundant, and in some cases, so is time to fly. In some clubs having a "couple" and then flying is tolerated because so and so is perfectly capable of flying after six beers. Rumour has it that someone is even fighting for his right to drink and fly in court.

For those people who think it is fine to drink and fly, please consider the following:

Accidents happen and the cause of this might be pilot error, interference, equipment failure or one of many other reasons. Should someone be injured or killed in such an accident, regardless of the cause the following is likely to happen.

In the case of death, there will be cops asking lots of questions including pesky ones about alcohol. You might explain your way out of trouble with the cops but the family will soon arrive. Imagine having to explain to them what happened with the smell of beer on your breath. Also consider that they probably lost their breadwinner, father and husband and will need to sue you as a result. Your trouble does not stop here because no insurance company will pay a cent if you transgressed the rules. Loss adjusters are experts at finding reasons not to pay. I don’t know of many people with a few million rands in reserve for eventualities like this so you will probably lose everything you own.

No matter what the cause of the accident, you will be asking yourself the following question for the rest of your life. Could I have reacted quicker and prevented the accident if I did not have that beer?

Before you open that beer please think and reconsider.

Wednesday, December 14, 2005

Friday, December 09, 2005

Thursday, December 08, 2005

Note on the use of BECs in electric gliders from Andre Kilian


Just a few notes for the electric glider guys. I have observed a few cases where the guys are using some of the budget brushless speed controllers on the smaller electric gliders (e.g. Hawk 1400) and have "unexplained" crashes due to loss of control, and after checking the equipment after the crash everything seems to be working fine! The problem is mostly due to the BEC circuit overheating, and results mostly from the use of a 11.1V Lipo with more than 2 micro servos, or with 2 servos that do not move freely (e.g. aileron control horns).

My suggestion is to use a proven brand of speed controller, be very careful when using more than two micro servos (they normally draw more current than standard servos) and make sure that they do not bind. It is also preferable to use micro servos designed specifically for the collective pitch micro choppers, as these normally run on 4 servos and a BEC s peed control. Some controllers also come with an additional heat sink, such as the Align brand (good quaility but expensive) and the Melody (good quality at very reasonable price). It also helps to keep the controller away from heat sources such as batteries and motors, and never velcro the controller to the fuz!

The other problem is that the guys with the 2-3m gliders use the BEC controllers with up to 6 servos (4 in the wing, rudder and elevator) which is a recipe for disaster. The same principles as above applies - with these gliders rather disable the BEC circuit and run a seperate battery pack on the receiver or use a seperate BEC unit.

As these notes are based on practical experience, it would be useful if our electronical boffins can explain why you have to dissipate so much heat on a BEC unit to bring the voltage down from 12.5V (3S lipo) to 4.8V. l have seen that if you stir the sticks on any micro heli with 4 servo s for longer than 2 minutes without running the main motor, everthing stops working (BEC overheats) but if you fly it is fine!



2006 F3J gliding team -- update from Ilma Stockton

Link to the F3X site for info

Sunday, December 04, 2005

Action photo of a glider launch done by the local Vaal Model Glider team at the 2005 Vaal Triathlon.
(Tony Neerings on left the time keeper, Gert Nieuwoudt the pilot and Hugh
Edmunds assisting).
Photo sent in by Gert Nieuwoudt
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