Tethered Flights
In response to numerous requests to bring our balloons to special events such as school fetes, corporate launches and parties, we have developed the following policies and guidelines.
Types of Tethered Operation
In ballooning, we talk of static tethers and tethered flights. A static tether means that the balloon is attached to a single rope but kept on the ground after inflation. A tethered flight means that the balloon is anchored to 3 long tether ropes, and taken to the end of those ropes, approximately 40'-50' above the ground.
Operational Limitations
Tethered flights are practical and trouble-free in wind conditions of 5kph or less. Unlike a balloon in free flight, a tethered balloon tends to heave and strain against its tethers in winds that are either faster than that, or gusting. It follows that a balloon in such conditions is easily damaged and difficult to control. Indeed, almost all the damage that we have ever sustained to our balloons during the last 15 years has occurred during tether work in gusty conditions. In this context, damage mainly means scorched scoops, burnt envelope panels and distorted karabiners.
It is also bad practice to operate a balloon in high ambient temperatures and under a scorching sun. Extended exposure to ultra-violet rays from the sun and to temperatures of more than 115°C inside the top of a balloon envelope will dramatically shorten its life. Balloon envelopes have a working life of only about 500 hours anyway, so careless treatment of them can be very expensive.
Given the extra stresses that tethered work places on our equipment, we are cautious about how many tethers we do each year. Even when we agree to do a tether, we almost always limit it to an hour or so.
Practical Limitations
Most of our work involves passenger flights in the early mornings and late afternoons. Morning flights together with a celebratory breakfast afterwards take 5-6 hours, after which we must clean our equipment and re-fuel the balloons. Thus, even if our pilots and crew forego a short siesta, we cannot usually commit ourselves to tether work before early afternoon.
Beyond that, we must assess other issues such as wind speed and direction, the amount of wind shelter available, the ambient temperature, and the intensity of the sun before deciding whether or not to go ahead. All too often, the harsh Australian sun combined with thermic activity created by that sun, conspires to stop us.
The Seasons
Statistically, Autumn is the best time of year for afternoon and
evening tether work. Surprisingly, Winter can also produce some magic days.
While Summer is often too hot, Spring is the most fickle time of the year. Guess
what? Most schools seem to have their fetes and athletics events between 10.00
am and 4.00 pm on hot, sunny and windy Spring and Summer days, exactly when
we can least guarantee to make a tether work.
Night Glows
A night glow involves putting a balloon on a static tether so that it lights up like a Chinese magic lantern. Night glows are particularly impressive when a number of balloons are brought together.
Because night glows are done after dark, the odds of success are markedly better than for tethers done during daytime. It's often the case that high winds during daytime abate dramatically at dusk, and remain gentle for some time.
As a company, we are more open to requests for night glows than for daytime tether work. In operational terms, the odds of success are better; in practical terms, we're more likely than not to have pilots available; and, in terms of self-promotion, they work well.
Criteria for Acceptance
As a company, we are too small to be able to say yes to everyone who asks us to tether a balloon for them. When making a decision about whom we can help, we consider the
• time
of year
• time of day
• statutory duty time
restrictions
• distance from our base
• needs of the organisation making the request
• fund-raising and educational potential
• possible publicity benefits
to us, and
• our other commitments.
Costs & Prices
Unless paid by a sponsor, it's impossible to make any money from tether work other than by charging ridiculous prices. At best, at the rate of only about 5 people every 10 minutes, we can only carry about 30 people an hour. Accordingly, for tether work close to our operational bases, our policy is to seek reimbursement of our costs, charge nothing for our time, and treat each tether as both a community service and publicity exercise for ourselves. For a one-hour tether, that usually amounts to $150. Of that, $120 covers the amortization of the balloon envelope, and $30 pays for some of the propane we use. Furthermore, we usually require at least a couple of able-bodied volunteers to help us with rigging and packing up the balloon.
For tether work outside Bendigo and Adelaide, we also have to consider both our travel costs and opportunity costs. Accordingly, we usually ask organisers to arrange an untethered flight at normal commercial rates after which we stay on to do a tether for cost price. Sometimes on such occasions, we also need to ask for accommodation and local crew if we're unable to drive over on the day. Normally, filling a basket or two for a flight over the passengers' own town is not difficult. Because hot air balloons are so rarely if ever seen over most small country towns, such occasions generate huge enthusiasm and support.
Other Options
If we can't come to your special event, don't give up. There are other companies and organisations that might be able to help you. While our work is mainly concerned with taking paying passengers for joy rides, they have balloons that are designed for tether work. Although they are generally committed to a pre-set tour schedule around the country, they might come your way if you ask them nicely.
Sponsored balloons that are known to us include
• Tall
Poppies, owned by the Australian
Institute of Political Science
• RAAF,
and
• Cadbury's
Freddo Frog
Last updated: 5 September 2002