Fuel Exhaustion

Running out of gas in any vehicle can usually be traced to “pilot” error. However, in a balloon, sometimes bad luck can play a part and present this unfortunate situation when you least expect it. The book concept states that “It’s better to land in control (with fuel) than to chance a landing in a location picked by the balloon when the fuel is totally exhausted”. This sounds good but the realities are sometime quite different.

Below is a “low fuel” story submitted by a reader. I will attempt to critique and make points about events leading up to the final landing. This is a real life situation and not uncommon, as depleted fuel is usually a result of calm winds which is the condition we balloonists look to fly in.

“Well, in my particular case, all of my various instructors had always taught me it was better to “go in” controlled rather than risk crashing into a house, powerline, car, persons, whatever.

It was Aug 26, I had 3 people in the balloon and it was a morning flight. We’d been flying about 55 minutes when I asked the crew to seek landing permission in a field that I was (very slowly) approaching…the landowner was very short, and nasty and said “NO”…I looked at the fuel and at the time still had 50% in each tank (18 gal tanks).

Plenty, right? Well, it was hot & rather humid so the balloon was using fuel faster than it normally would. I spent the next 30 minutes trying to get some wind to push me into another nearby field. Eventually I gave up and ascended… no wind there either. I had to go to 1,300AGL before finding anything at all… and it was about 2mph. I positioned myself over a good field and began a terminal descent.

Well, passing through 400′ agl it was clear the wind had changed its mind and was now blowing towards the trees. Beyond was a hill and past that, the 2500′ Blue Ridge Mountains. Fuel was at 20% in each tank. I was starting to hear burner pressure drop and from the sound, you could tell you were suckin’ the last few pounds…

Even so, the wind was very, very light. I was only 200′ from the field I wanted to be in. I threw the dropline in hopes the crew could grab it and pull me through, but the underbrush was too thick. Looking around, I could tell I was over very small trees, 15′ at the most, and nearby they were a lot taller, more towards 100′. I let the envelope rub up against the tall trees, this (very) effectively stopped all movement as the wind was very slow.

I told the passengers what we were going to do, and that they needed to crouch down inside the basket. The crew was able to break away most of the trees directly below us, as I kept the balloon in a “hover”.  Slowly, I began to come straight down, I kept the vent open all the way down so the trees could push the fabric in rather than poking through it. This worked like a charm, and we settled straight onto the dirt.”

I closed the vent and determined it would be best to use the Aerochute and pull the envelope straight down into the basket, of which 75% made it in, the last 25% collapsed over the tree tops.

And hear this, NO DAMAGE!!!!!! NONE! Not even a small hole, I couldn’t believe it myself, we flew that night again, there were no holes, anywhere!

Story points:

  1. The pilot sent his crew in for permission before his approach. This is an excellent practice when possible. Unfortunately he was met with a hostile land owner.
  2. The pilot spent the next 30 minutes working towards an adjacent field. This maneuver may have cost him an optimum landing site.   Experience has taught me to be cognizant of the difference between real and “teaser” winds. When little or no progress has been made in 10 minutes or so, sometime it’s best to make that big move to the sky right away. The pilot ascended to 1,300’ feet agl before getting some movement. Good decision. This ascent should be fairly rapid up to any point of ground track movement (away from the mountains) as it is unlikely that there is a “real” wind anywhere near the surface.
  3. The pilot positioned the balloon over a good field and initiated a steep descent. Excellent move. That’s what steep descents are for. Unfortunately, the balloon fell victim to some low winds that sent him towards “No man’s land” A pilot should always avoid allowing the balloon to reach areas bounded by mountains or other inaccessible areas. It leaves you no choices. You must make an evasive move (or try) before you get there. However, when you are ultimately faced with what looks like one last opportunity to get into a good field, you have to make it count. The pilot must have a good idea of the lower winds before committing to the descent. This can be done by spitting and/or crew contact. The pilot must be sure that he has navigated to the optimum location so that the low winds can be offset during the descent. I would personally use most of the remaining fuel for this positioning as a properly executed steep descent from the correct position over the field will produce a high percentage of successful landings.
  4. The pilot descended and let the balloon “bounce” off of the taller trees downwind while throwing a drop rope. This appears to be the proper move. It is important to evaluate the trees you plan to collide with. Only “friendly” trees in light wind will allow you to escape damage to the envelope. I find it less damaging to have a very slight “up” in progress at the first contact with a tree.
  5. The pilot briefed his passengers on what was going to happen. Very good thinking. It is wise to advise the passengers to watch their faces and perhaps stand in the rear of the basket before a tree collision. Protruding branches can be very dangerous. It is also prudent to “tuck” you control lines at this point so that the tree doesn’t “catch” a vent line and initiate an unscheduled deflation.
  6. The pilot “slipped” the envelope down through the trees for deflation. This is the proper technique for “in the tree” deflations. The trick is to gradually shrink the “lift bubble” so that it’s just barely holding up the near streamered, vertical balloon. From there the envelope will generally settle straight down with minimum damage.

The road to “fuel exhaustion” is wide and varied. Sometimes it’s just one little thing that can make the difference between ending up tree bound or in that nice open field next to a road.

My thanks to the reader who sent in the story. My critique was not intended to second guess his decisions but to give some possible insights and alternatives, given the circumstances. I honestly think he did a great job and I hope we all have as good an outcome when faced with a similar situation.