VARMS - SAFE WINCH OPERATION PROCEDURES 31/7/19

The following is for the safe operation of a winch when launching a model glider. It refers to a winch with an on-off type switching mechanism operated by a foot switch on a cable. These procedures are to be read in conjunction with current VARMS Standard Operating Procedures

A high powered and very high speed competition winch

GENERAL

• A winch is a very powerful device and must be used and treated carefully.

• The line can reach high speeds, wearing eye protection (eg sun glasses ) at all times is a good idea.

• For safety, the parachute and it’s connections should be free of metallic parts. LAYING OUT THE LINE.

• Fix a peg to the winch on one side.

• Thread line through turnaround pulley.

• On the end of the line , slide on a sleeve made from cord outer casing. See photo.

• Tie a simple overhand knot to form a loop for parachute attachment. Pull the knot tight. Attach loop to hook on the winch.

• Walk out pulley to full extension of the line making sure which is the top line.

• Peg down pulley firmly to ground. Use long pegs for soft ground.

• Walk back to the winch holding the top line in one hand and the ground in the other. Walk a straight line between turnaround and winch. Keep lines separated.

• Attach parachute to end of line and then to the hook on the winch.

• Attach foot switch cable to the winch, connect battery, engage clutch.

• Briefly tap switch to give light line tension.

• Adjust the winch position so that the line is at right angles to the drum and will wind on evenly.

• Peg down the other side of the winch.

USING THE WINCH

• The objective here is for the line to wind onto the drum evenly when the model is launched.

• This may require further adjustment of the winch position relative to the line.

• Before launching look around 360 degrees and especially

• Yell ‘launching’ before launching glider, wait, launch glider WINDING IN THE LINE – COMPETITION WINCHES This can be done in two stages:

• Anticipate the last launch of the session and as soon as the model is free of the line, the winch can be wound in carefully.

• A taping method for the switch prevents the winch from building up excessive speed.

• The parachute will provide line tension so that the line winds onto the drum evenly without loops.

• Stop winding as the parachute reaches the turn around. This is more easily done by an assistant rather than the pilot.

• Walk to the turnaround and undo the parachute to allow the line to pass through the pulley.

• Reconnect the parachute to the line and tie the parachute into a simple knot.

• Return to the winch taking the turnaround pulley with you.

• To wind in the remainder of the line safely requires that there is some line tension. This gives even build up on the drum and prevents loops forming. A stop start approach ( i.e. tapping on the switch) is the best.

• The cable to the foot switch needs to be 2.0 metres or longer. This keeps the operator well away from the rotating drum.

• Stand on the turnaround side of the winch as far away as the switch cable will allow. Wearing a heavy leather glove, hold the line in one hand and the foot switch in the other. Briefly pulse the switch as you provide light line tension and guide the line onto the drum.

• Do not allow the winch to build up too much speed.

• Watch for the parachute to approach you and keep the pulses slow.

• As the parachute reaches approximately 2 metres from you, stop pulsing the winch

• Disconnect the battery and manually wind the drum to complete the wind in. WINDING IN THE LINE – COMPETITION WINCHES - ALTERNATIVE METHOD An ALTERNATIVE and much safer method for winding in the line, is as follows. You will need a plastic drum on a threaded rod mandrel with a tubular rotating handle. This is attached to a 12 volt cordless drill, connected to the winch battery with alligator clips.

. WINDING IN THE LINE - ALTERNATIVE METHOD contd

• After the final launch allow the parachute to fall to the ground without winding the winch.

• Disconnect the battery from the winch

• Disengage winch clutch

• Go to the parachute and remove it from the line.

• Walk back to the winch bringing the line with you.

• Remove the line from the winch drum, attach it to the plastic drum and use the device to wind the line onto the drum.

• The line is now ready for your next session. WINDING IN THE LINE - CLUB WINCHES

The club winches use a different method of winding-in due to the size of their parachutes and

the lower power of the winch itself.

After the last launch for the session the parachute should be removed and replaced with a

retrieval mouse. This is a piece of cloth with a loop for attaching to the end of the line. One is

with each winch. The winch tension MUST be set to the lightest setting before retrieval

commences. The winch line can then wound-in using small pulses until the mouse stops at the

turn around. The operator or a helper must then go to the turnaround and pass the line thru

the pulley by removing the mouse and when line is free reattaching the mouse! This ensures

that the line has some tension on it and can also be seen by the operator when doing the final

wind-in. The winch wind-in should be stopped when the mouse is some 10 metres from the

winch and the final line should be wound-in by hand. Loose line on the pulley causes loops

which can catch on the winch. Very short pulses MUST be used.

SAFE CHARGING OF WINCH BATTERIES The battery should always be disconnected from the winch on the field after flying is finished and before it is taken back to the clubrooms. Before connecting charging clips to the winch battery always ensure one of the leads connecting the battery to the winch is disconnected.

The green terminal connecting the winch to the battery is disconnected here The red terminal connecting the

winch to the battery is disconnected here SAFE CHARGING OF WINCH BATTERIES contd Before moving the winch from the charging point turn off/unplug the charger at the mains and remove both charging clips from the battery terminals. Do not reconnect the lead from the winch to the battery until the winch is set up on the field – see LAYING OUT THE LINE above VARMS WINCH LINE TENSION ADJUSTMENT Both VARMS club winches have an optional tension adjustment that allows the winch to be operated continuously without the on/off method used for competition winches. They can also be operated without the tension adjustment.

The black switch has 3 positions:

• off,

• on with tension adjustment,

• on with no tension adjustment

The lever with the black tape changes the tension: 4 is minimum tension, 9 is maximum tension

The lever attached to the spring is the tension adjustment

3 position switch Pulse is used with tension adjustment. Power is used with no tension adjustment