We are lucky to have a professionally-built winch for launching when we are not using the towplane. The V8 engine drives the 6000' drum via an automatic gearbox. We use Tost weak links: the Blue for the Twin and choose your own for your single-seater.
Our winch was designed for wire. We have used single strand high tensile for many years. This worked well enough with a skilled driver but launch heights were not great and we had many breaks. We swapped to using a section of multi strand wire. This reduced our breaks but was very heavy and our heights were reduced a little more. After following developments in NZ and other countries we decided to trial a 1km portion of synthetic rope. This has worked really well and gave a smooth launch. The only breaks were caused by either the remaining wire or the wire/rope join.
In 2005 we finally ditched all our wire and replaced with 4mm Dyneema. This is a very light and strong synthetic rope with good abrasion resistance. We got over 1000 launches from this but it accumulated a bit of damage in the learning process and was getting a bit short. During winter 2014 we purchased new and thicker dyneema.
Launch height is typically 1500-1800' AGL (no wind) for our Twin, and 1800+ on singles with 2500 not uncommon given a good wind.
A few reminders for winch drivers
* Use 96 Mogas or Avgas
* Check fluids! Oil, water and transmission fluid.
* Use 2nd gear, (pull the drive all the way back).
* Accelerate at a moderate rate
* Think SAFETY at all times
* Study the instructions below