Rewritten June '96

This article was written with the following systems in mind:

However many of the points discussed apply to other types of hang glider towing systems. I have seen various systems come and go in the Flatlands over the years and the `KISS' car tow has remained clearly dominant - more than 90%. It wins on all accounts - cost effectiveness, simplicity, ease of training an operator, initial financial outlay and able to acquire equipment to assemble a system at short notice.

Those who have been flying the Flatlands for a few years or regularly tow in a group on weekends will be familiar or identify with many of the points raised in this article.

Collectively our team has well over 2500 tows and has developed these guidelines over 8 years of towing together recreationally and in the Flatlands. The main thrust is efficiency and convenience, through preparedness and anticipation of problems ..... to fine tune team work.

It is not a guide on how to learn to tow and assumes you are already familiar with basic procedures and safety obtained from a tow endorsement course.

Make sure all your equipment is functional and preflight checks are done before lining up to hook onto the tow rope:

* Radio can Tx & Rx, ie battery not flat.

* Mike or headset plugged in.

* Able to lock on mike.

* Release is functioning.

* Release line for skyting bridle not too short which will cause a premature release as glider rises off shoulders. This can be checked by yourself without annoying other pilots for assistance.

* Bridle untangled and stowed tidily, ready to hook on.

* Bridle attached to waist or lap cord.

* Hang check.

* Weak link ready.

Do a radio check before the driver leaves for the other end (start point). If there is no one else nearby and the driver is sitting up the other end oblivious to your radio problem a lot of time is waisted.

You should be hooked on and completely ready by the time the driver is attached at the other end otherwise you will be a hindrance to the team. If there are a few disorganised ditherers in your team have a second pilot also ready to go.

Leave the launch spot clear until the driver has dropped the rope at launch. This allows the driver to come right up and drop the rope in the correct spot, continue through the launch area and do a U turn. The pilot will still have time to carry the glider to the end of the rope and be hooked on before the driver is ready at the other end. This avoids such things as:

the rope being dropped short of launch;

the vehicle beginning the turn as it approaches launch leaving a bow in the rope;

the vehicle having to manoeuvre to turn around and driving over the rope;

the need for another person to pull the rope back to the hang glider or;

the pilot walking forward to hook on, thus obscuring their view of the windsock or streamer.

Follow a standard routine radio procedure:

Acknowledge each other's primary transmissions. It can be worrying to a nervous pilot when they hear no response to a request. ("Is my radio working?!!")

Give your driver warning before you say "go, go, go", for example "picking up glider" and wind conditions. It is a common mistake for nervous pilots, when hearing the driver has hooked on and waiting, to simply pick up the glider and say "go, go, go".

The pilot should decide how much tension or lack of (s)he wants to start with but should always take up tension to approx 15 kg first. Do not launch without having pulled out the bridle firmly away from the pilot. I have seen some experienced pilots (not tow) take off with one arm over the top bridle line to the keel. This usually ends in a ground loop and a broken upright. I've also seen the top rope caught under the side of the helmet and pull a helmet or headset off. Also if the release line is too short, or is wrapped around the base bar or a grass tussock, taking up line tension will reveal this. This is preferable to an accidental release after you say "go, go, go" and having to get the rope back for another attempt. If the driver is not ready to take up tension, walk backwards with your glider to pretension the bridle and clear your release line.

The wind does not have to be 5kts straight up the strip for a successful launch. True, this will allow an easy, effortless launch but on light wind days the thermal is probably behind you and you will be back on the ground in 5 mins wondering why everyone else is away 1st tow.

I mention this because after a great day I get back to the pub to hear how a team only achieved a launch every hour because "the wind wasn't coming up the strip much of the time" and half the team didn't get away and the others launched so late that they only flew 10km just before dark!!

I am not advocating launching tail wind. This is just possible with up to a 2kts of smooth constant tail breeze and the ability to sprint very fast, but it is very risky in thermic conditions. Also if you get a low weak link break or an early tow vehicle problem, you'll be landing tail wind as well.

These are my personal limits: - from 900 cross - 1-2 kts (kicked dust drifts about 1'/sec).

- " 600 " - 5kts.

- " 450 " - 10kts, etc.

Also consider point #1 in advice `For The Driver'.

Turn the glider slightly into the wind (» 10-200) but not fully and keep the upwind wing slightly down. Be prepared to do a weight shift jab to the side to keep that wing level just as you launch. As you ground skim you may slide sideways across the ground. Do not try to fly the glider back over the strip but keep the wings level and allow it to slide side ways over the ground until you are clear of the ground. I have done cross wind launches where I was sliding sideways across the ground at 10+ kts.

If you are not very tow experienced, when trying something new like this, gradually increase your limits of acceptable launch conditions along with your confidence.

Unclip your radio once at a safe height to reduce annoyance to other radio users (eg 300'). Ensure you have heard the driver confirm your release as a check that you have unclipped your mike. Because most of the UHF frequencies will be in use your team will be unable to change to another channel. The other unlaunched pilots will be effectively grounded until you remember or your battery goes flat. In the latter case you will be unable to give a position report for retrieve; not that anyone will be inclined to go looking for you.

Local rule - Leave your mike clipped on and you buy a carton of beer for the team.

With a skyting bridle, if you are comfortable in hang while on the tow, stay in hang until you release. Hands on the uprights gives you more lateral control when a thermal pops a wing up and makes it easier to dampen out oscillations leading to a lock out. Also your helmet stays clear of the top bridle line when higher on the tow.

When in lift, release immediately even if there is full tow line tension. I hear many pilots call out "stop stop stop" when they want to release and wait for the tension to drop before tugging the release line. Too late!! The thermal is behind you and on marginal days, chances of finding it are slim. Never lose contact with the lift.

This golden rule with any competent mountain pilot also applies to towing.

Releasing under tension usually ensures your release operates cleanly anyway. Releasing with no line tension is a hang over from winch tow training to prevent wire tangles. If you have a stretchy bridle and a lump of steel on the end of your bridle, you're more likely to get a nasty surprise with a low altitude weak link break.

In different wind conditions the pilot can benefit from different vehicle start techniques.

In light winds are your pilots getting a lethargic take off, moon walking until the glider is properly airborne or wafting into the air barely above the stall then pancaking onto the ground? After taking up the tension perhaps you could try the following techniques in different wind strengths.

> 5kts head wind component: start with the "take up" tension (approx. 15 kg).

2 - 5 kts head wind component: After taking up the tension reverse up until the tension is nil.

< 2kts head wind component: After taking up the tension reverse up until the tension is nil then
another 3 - 5 metres. Don't do this if the tow gauge is mounted to one side of the vehicle as a wheel will reverse over the rope and may damage the gauge.

Above all, always use maximum acceleration (without wheel spin) until you have normal towing tension except in strong wind (ie > 10kts). You might think this will abruptly snatch the pilot into the air but there is adequate stretch in 600 metres of 5mm rope for this to become just a quick and smooth increase in tension at the pilot's end. The problem when you start with significant line tension in light wind stems from the fact that with nil wind the glider will have a ground speed of approx 30 kph from the moment of launch. At the same time the vehicle which began with 15 kgs of line tension travels about 3 metres in a couple of seconds reaching maybe 10 kph before the rope tension is enough for the pilot to take their first step for launch. So what happens when the glider which is attached to the tow vehicle with a fixed piece of rope is travelling 20 kph faster? To make matters worse the glider is able to accelerate quickly and there is some stored elastic energy in the rope but the 3/4 tonne vehicle can only accelerate sluggishly especially on loose dirt.

At the moment of launch the above recommendations will have the vehicle travelling at a similar speed to the hang glider and avoid that sudden loss of tension just as the pilot leaves the ground. The pilot has to either tell you how much pretension or slack (s)he wants or inform you of wind conditions at launch. Otherwise the general conditions of the day will give you an idea what type of launch technique to use.

Many drivers do not realise that for the first couple of seconds the pilot is holding back allowing the tension to build up before taking the first step. Meanwhile the driver who sees the alarming increase in tension hesitates or even brakes just as the pilot decides to go. Before you can get the vehicle moving again you may lose most of your tension. In light winds do not hesitate until the tension is at least up to a strong tow tension. We have found it very helpful if the pilot can say "airborne" when they are a couple of feet into the air. Only then should the driver begin to adjust back to normal tension. Before this, accelerate at maximum to achieve a high tow tension. Consider that up to 20 kg of rope tension is due to the full rope length being dragged along the ground. At this phase there is less danger of breaking a weak link than you think.

Always give the pressure gauge 90% of your attention and 10% to steering the tow vehicle down the strip. Forget the speedometer. Do NOT look in the rear vision mirror as the tow tension can drop or rise very suddenly and break a weak link. Be ready to brake the tow vehicle suddenly. The quicker the tension rises the more urgent a response is required.
The more thermic the conditions, the lower the desired tension. In strong thermic conditions maintain the tow line tension near 50% of the weak link rating to give adequate margin to avoid a weak link break. Once the weak link breaks the tow is finished and the pilot can only make the best of their present situation. The pilot can aid the driver by telling them they are encountering a thermal or "noisy air". This warns the driver before any indication on the tow gauge and if their attention is wandering, brings it back to the tow gauge.

Clear your rope from adjacent strips ASAP and return it to the launch area quickly. The time proven method is to simply do a U turn without pausing and head back to launch. 50 kph is a reasonable speed. Stationary ropes are quickly sliced by other ropes being pulled over them so keep yours moving. Do your U-turn away from the side that the rope has fallen towards, so you don't drive over it or drag the rope across itself. A U turn means you do not have to leave your mowed strip to find the other end of the rope nor get out of the vehicle to pick up the end.

However it does mean a different end of the rope is at launch each time.

Know the radio frequency and the names of drivers on neighbouring strips in case problems occur requiring co-operation.

If your team is towing near the edge of the paddock and your rope has fallen over the fence, continue up the tow strip until the tow rope is pulled off the fence and back into the paddock before doing a U turn. To judge this, after the rope has fallen estimate how much rope is over the fence and use your odometer or trip meter to indicate when to turn around. It is better to go a bit further than necessary than to leave the rope partly over the fence as you will need to pull it off the fence by hand on the way back to launch. Check that the rope has cleared the fence as you drive back.

Any hardware such as metal rings on the rope ends are likely to flick around the top wire of the fence and anchor the rope. Keep your speed near 10 kph and either watch the gauge closely or constantly look behind at the rope for signs of sudden tension otherwise you may break the rope, damage your gauge or pull the fence over. It is much safer to pull the rope off the fence with the rope end in your hand as you continue driving ahead. However make sure that it is not wrapped around your hand or fingers in case it is suddenly snatched from your grip. It would be safer to fix a small snap hook to the right rear corner of the vehicle with a light weak link. This position allows the driver to observe the rope in the side mirror. 1 strand of #8 twine is approx. 25 kg. Have several weak links tied to the vehicle ready. With only a small spliced loop or a bowline on the end of the tow rope and no hardware, it almost never gets caught on fences, bushes, etc. You can confidently pull the rope off fences at faster speeds with it still attached to the tow gauge.

8 Rope Return after Early Release - If there is an accidental or early release in the first 100 metres of the tow it is often quicker for an extra person to run forward and drag the rope back. Remember if the rope was released under tension it may have sprung forward a considerable distance.

It is usually better for the driver to disconnect the rope, follow it back in reverse, then hook on again. This is far better than somebody pulling on the rope against the vehicle and trying to wave to the pilot to ask the driver to reverse up over the radio. There is also a danger of reversing back over the tow rope while still attached to the vehicle and damaging the tow gauge. For this reason it is preferred to mount the tow gauge centrally on the vehicle rather than to either side.
If there is no extra person available the driver should (a) drive forward until they are the length of the tow rope from the vehicle start point and then do a U turn to return, or (b) drive forward until they are reasonably sure the rope is straight and pulled back onto the tow strip before unhooking, finding the glider end and towing it back to launch. (b) is appropriate if the glider released very early and reduces wear on the rope.

9 Reversible Rope Ends - Have your rope set up so it can be end-for-ended. This may involve each pilot being responsible for their own weak link system and be able to quickly hook onto either end of the tow rope that has no hardware attached.

10 Streamer at Vehicle Start Point - Stand a small windsock or streamer just in front of the vehicle start point. This makes it easier for the driver to quickly find the end of the rope as (s)he drives back to the start point, especially when looking into the sun. The pilot can also ask the driver what the wind is doing near the vehicle as a gauge of thermal activity.

11 Remote Release - Install a remote release on the vehicle tow gauge that the driver can operate while driving. The driver will only have to get out of the vehicle once per tow, to attach the tow rope just before each launch, saving minutes. When returning the rope to launch, glance behind occasionally to check that you still have the tow rope attached. It is a bit embarrassing if you turn up at launch empty handed and also time consuming to find the end again. A remote release also adds safety if a pilot locks out or gets into other difficulty. This can be set up like a lanyard routed outside the vehicle to a roof rack above the driver's window or an arrangement similar to a motor bike brake cable.

12 Tow Gauge Weak Link - Install a weak link at the vehicle end about 50% stronger than the pilot weak link. This will protect the rope from being damaged if it should snag on a fence or become tangled with another tow rope. It will also protect hydraulic tow gauges which are often damaged and loose calibration if subjected to pressures approaching full scale deflection or more. A suggestion is 6 strands of #8 nylon bricklayers twine. Replace this weak link daily. If you have a remote tow car release consider what will happen if this weak link breaks. Don't do what others have done in the past - put the weak link between the vehicle and the tension sensing unit!

Have the driver familiar with an appropriate in-line knot for joining the tow rope in an emergency. This knot should be quick to tie and of minimum bulk. This is to reduce wear while dragging the rope along the ground and to assist it to run around objects or over a fence. A suitable knot is a "fisherman's" or "climber's knot" with approximately 20mm free ends that are easily included in a protective wrap. The following knots are not suitable: 2 opposing bowlines, reef knot or a combination of half hitches. Keep a sharp knife or scissors in the vehicle, and tape to wrap up the joining knot. Brown packing tape seems to resist reasonable wear and is cheap. Electricians tape and ducting tape are not as good. Cloth reinforced tape may be the best but is expensive.

After release from the hang glider a loose falling rope can put knots in itself. This is more likely after a high release in light and variable wind conditions. Typically, knots form near the glider end of the rope as it falls through itself. Most are within the first 10 feet but may be up to 50 feet from the end.
The tension of a couple of tows will seat these knots firmly and you will not be able to undo them.
If ignored the knot will be a wear point eventually creating a rope break. Glance back down the rope as you attach it to the vehicle to check for these knots and undo them then.
Similarly but less common, loop-through knots can form anywhere along the rope.
Cast an eye along the rope as you hurry back to the vehicle end for the next tow.

Roll your rope up each day before leaving to retrieve the pilots. There is no guarantee that you will be on the same strip the next day due to wind changes and strip rotation. The next morning when other teams drag their rope around the paddock to a different strip over your rope it will be cut in half in less than a minute. If you are last onto the paddock it could be in several pieces. If due to circumstances you do leave your rope out over night and need to drag it to another strip, be considerate by having someone hold it clear of other ropes you encounter. Similarly it is not a good idea to leave your rope laid out until you return that evening to roll it up. There may have been a wind shift after you left the paddock and every one moved to cross strips. No one is going to roll your rope up out of the way in the hurry and confusion. Also, at the end of the day, Free Fliers may have a tow in another direction. Even with towing continuing on the same strips it is possible your rope could have others falling over it and be damaged or get caught up and dragged away.

Before towing commences each day take the knife and tape and walk along the rope inspecting it for worn joining knots, accidental knots and pulled strands. It may only be necessary to add more tape to the joining knots. Otherwise cut out any problem areas and replace with the in-line knot. This 15 minute chore could save at best a 15 minute delay in the middle of peak towing time. At worst most of your rope may be unfindable after a pilot drops it from 1000 feet and/or it gets caught up and dragged away by another rope.

Alternatively, butt splicing gives only a slight increase in rope diameter thus reducing the wear associated with knots. With protective tape a splice will last a long time before needing attention.