Frequently Asked Questions - Cable Retrieve Winches

Q1 Is it easy to operate? how do I know when to engage the retrieve winch?

Q2 How about the main winch? what is different?

Q3 We would only need a single drum main winch, are these cheaper?

Q4 Does it affect the launch height?  is it steel or synthetic cable?

Q5 What happens in strong cross-winds on a narrow airfield?

Q6 What happens if there is a cable break?

Q7 What if the end of the cable is pulled in too far and hits the winch rollers?

Q8 How long does it take to retrieve the cable?

Q9 How much fuel does it use?

Q10 Are parts easily available / servicing straight forward?

Q11 Is this system proven and successful over time?

The answers....

<Q1 Is it easy to operate? how do I know when to engage the retrieve winch?

Yes, drive lever (go / stop lever) is engaged immediately when the glider releases and the parachute opens, the pre-set speed control is lowered as the launching cable approaches the winch. Cable brake is automatic.

Q2 How about the main winch? what is different?

After glider release, the operator regains cable tension (as normal), engages neutral and applies tow-out brake or, depending on winch type, controls brake manually. Most drivers comment it is easier than vehicle retrieve systems.

Q3 We would only need a single drum main winch, are these cheaper?

Yes.  (See Skylaunch 3 price lists)

Q4 Does it affect the launch height?  is it steel or synthetic cable?

The cable drum reel-out is free running.  The extra load on the glider is the weight of the retrieve cable in the air, approximately 8 kg for steel cable and 1.5 kg for synthetic (eg Dyneema).

Many years ago, several gliding clubs made their own retrieve winches, often using a variety of old parts, but these designs produced much cable tension for the launch (unlike the Skylaunch design), therefore reducing launch heights.  This is how the launch height loss “myth” was created.

The winch can be fitted with either steel or synthetic cable.


 

Q5 What happens in strong cross-winds on a narrow airfield?

As both winches are pulling cable in after cable release, any sideways bow in the cable can be almost pulled straight before the cable lands, so it actually handles cross-winds better than with conventional parachute decent.

Q6 What happens if there is a cable break?

Cable drum braking is controlled by a tension roller, so if there is a break (at high speed) the drum will automatically stop, leaving less than 5 turns of loose cable on the drum. Both cables can be easily rejoined in the normal way.

For low simulated cable breaks, the cable is allowed to drop then retrieved as normal, when the airfield is clear. For high simulations, cable can be retrieved as normal in a lower speed setting.

Q7 What if the end of the cable is pulled in too far and hits the winch rollers?

This can happen occasionally as so many (unskilled) drivers operate these  winches.  The end of the cable is attached to the launching cable with a simple knot, acting as a weak link.  Because the cable drum brake is automatically applied, there will be no problem and the cable is simply reconnected, taking approximately two minutes.

Q8 How long does it take to retrieve the cable?

Typically, 45 seconds or less from glider release to cable back at the launch point, ready for next launch (see analysis of cable retrieving systems).

The launch and retrieve all happen as one rapid cycle, so the cable is quickly returned to the launch point to await the next launch.

Q9 How much fuel does it use?

Approximately 0.2 litres per retrieve, usually the same amount of fuel used by the launching winch to reel the cable end all the way in (when using a vehicle retrieve system). 

This also eliminates the fuel requirement of any cable retrieve vehicle.

Q10 Are parts easily available / servicing straight forward?

Yes, power unit is reliable Volkswagen, final drive utilizes popular industrial components. Brake system / guillotine / cable rollers / small fittings etc are standard parts as used on the Skylaunch launching winches.

Wheels / axles / tow hitch etc are universal trailer components.

Basic service is every 6,000 launches (retrieves).

The running costs will be significantly less than operating a vehicle retrieve system.

Q11 Is this system proven and successful over time?

Yes.   The first Skylaunch retrieve winch was delivered in 1994 to a busy club launching (retrieving) approximately 10,000 gliders per annum, has proven to be very reliable and is still used every day.