Nylon Gulliver

I've been working the crown line a lot lately when we're crewing balloons. If you trace out the anatomy of a hot air balloon, it all starts at a single piece of milled metal - the load ring. About the same cross section as a man's thumb, and about 8 inches in diameter, the load ring is the key.

The balloon itself is constructed by attaching about two dozen pieces of heavy nylon load tape (think half-inch wide seatbelt fabric) to the load ring. These load tapes run all the way to the bottom of the balloon envelope and become the vertical load-bearing parts to the balloon. Horizontal load tapes maintain the shape, and the colorful nylon - which keeps the air inside, but doesn't carry the weight - is stretched to fill the gaps between the load tape network. When the balloon is in flight, everything ultimately dangles from the load ring; when on the ground, the position of the whole balloon is maintained through control of the load ring. That's where the crown line comes into play.

The crown line is a rope connected to the load ring. You maneuver the load ring from the ground with the crown line.

When we stand a balloon up, we first use a fan to cold pack the balloon with air. While cold-packing, the crown line is astonishingly boring. The balloon fills, and the crown line just dangles there. For the uninitiated, it would seem like crown line is the least interesting job at the launch site. That'll change, though.

Once nearly full of cold air, the balloon lies, sideways, on the ground like a sleeping giant - a sort of non-human gulliver. The pilot, once they deem it's time, ignites the propane burner and blasts the first wall of heat into the cold envelope. That first burn knifes a jet of heat into the mass of cool air. Finding itself confined by the balloon envelope, the warm air balls up like a fist and presses hard against the uppermost part of the envelope - a spot near the balloon's equator. As that first heat ball spurs the balloon, it looks for all the world like gulliver just quivered into life with a sudden heartbeat and a gasping intake of breath. The chest rises, the ribs and shoulders shudder and quake. Ripples run across the fabric, threatening motion like a stirring giant.

About this time, the pilot gives another jolt of heat. The fist of heat is enlarged to fill about half of the balloon envelope's volume. And with this, the balloon shudders more deeply, then rises to its feet, awakened and alive, towering above the lilliputians that are the ground crew, able - but for it's natural benevolence - to inflict great harm upon the small, frail beings who dare to believe they are the masters of the balloon.

And that's when the crown line becomes an interesting job!

A typical hot air balloon stands in excess of seventy feet from top to bottom. That's a seven story building. When it shifts from lying down to standing up, it takes about 10 seconds. The person holding the crown line must engage in a game they are destined to lose - applying pressure to the load ring so that the balloon does not wobble once upright. But not too much pull - because the balloon can and will lift you off your feet if you're not careful. Just prior to the balloon standing up, the balloon envelope and the crown line are stretched out in a straight line. Seventy feet of balloon to the load ring, then 100 feet of crown line rope extending beyond. When the balloon stands up, the person holding the end of the crown line moves from 170 feet away to about 90-100 feet away in about ten seconds. That's about 7mph or a healthy jogging pace. Except you have to have full body weight pulling back against the crown ring to avoid a wobbling balloon envelope once its upright. So in other words, the crown line attendant looses a tug of war in a controlled fashion, at a speed of a healthy run!

It's a balancing act, managing the crown line. But it's something most anyone can do. This morning, for example, my wife C handled Crown line masterfully. R weighs about 90 pounds: he's capable of crown line except on particularly breezy days. I like to run Crown Line because my personal favorite sight - that of the gulliver awakening - can only be fully appreciated from the Crown line's point of view.

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