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EAA Experimenter, February 1996
Fly Ball
A Baseball-Shaped Airship
By Stuart Fuller
(EAA 444349)
1178 Gunnel Road
Dallas, GA 30132
On a beautiful Saturday afternoon in October, I was 1200 feet AGL just west of Atlanta, Georgia on a routine training with Barry Jones, one of my current students. We had decided to fly cross country to Stockmar Airport, near Villa Rica, Georgia to do some touch and go's and visit Dogie Stockmar, the airport's owner, a great pilot and friend.
I was in the back seat of my Zephyr II, R582, which is registered with the USUA (United States Ultralight Association) as a two-place trainer. Barry was in front doing the flying. As we approached Stockmar, we radioed for an advisory and entered the pattern for one zero.
As we entered downwind, we saw what looked like a giant baseball on the ground in the grassy tiedown area. My first thought was that it was some sort of hot air balloon. Needless to say we were curious; after landing and securing the trainer, we walked over to look!
I was amazed to see that whatever it was, it had two Rotax 503 engines mounted on wing pylons, with Rotax C gearboxes and Warp Drive 3 blade propellers.
"Wow," I thought, "I've never seen anything like this!". I asked one of the fellows with the ship if I could take a closer look. He said yes. I quickly discovered that aside from two 503's on each wing pylon, there was also a small Honda motor with a Warp Drive prop on each wing pylon as a back up. Behind each 503 there was a set of four airfoil vanes used to direct thrust up or down. Neat!!
When I looked in the windows (Lexan) which go around the bottom of the ship I quickly realized this was not a hot air balloon. Inside I saw a platform with two seats (a la Quicksilver), a large wheel (like a boat) and a center console with a T-handle that controls engine RPM together or separately for directional control. Looking up inside I could see another separate air bag which contains helium. The bottom of the helium bag is well above head level, which means that outside air is pumped into the lower half of the sphere to maintain its round shape. On the ground this is done by fans run by generators. In the air it's done by air forced into inlets on the engine/wing pylon just behind the prop tip. It works great.
It seemed the crew was having some small problems with the engines as well as prop pitch adjustment. Being a full-time instructor and dealer, I offered to help if I could, as I've been flying Rotax engines for about nine years and have a pretty . well equipped shop with Rotax tools and parts, as well as Warp Drive protractors.
In the process of helping them make adjustments and minor repairs, I met all the guys. First is Hokan Colting, from Sweden, the inventor/designer of the spherical airship, as well as the test pilot. I gave him his first flight in an ultralight-type aircraft, and he really loved it. That led to doing some aerial photography of the airship in flight, using a video and 35 mm still camera. Bill McKinney, an aeronautical engineer on the design team, rode in the front seat of my Zephyr with the video while I flew passes (full flaps, 38 mph) around, by and under the airship. We shot some great video and had lots of fun. Because the airship can basically hover, we could get very close; some of the video is amazing.
The airship is really maneuverable; it can stop on a dime and turn 180 or 360 degrees very quickly, or pop up and down quickly as well. Yet, it is very stable in flight; top speed is about 25 mph with no wind.
Rounding out the crew with the ship were Dr. Bill Unger, PhD. (aerospace engineering) and David Loewen, a mechanical engineer. All of the crew are some of the nicest people I've met in aviation; as you know, that's saying a lot!
During the course of the two weeks that the airship and crew were in Atlanta I came to know the guys from 21st Century Airships Inc. and their story pretty well.
Hokan and most of the crew visited my home, airstrip and shop one day, and most of Hokan's crew took their first flight in an ultralight with me. They all loved it.
Here's the story of the ship's origin. Some years back Hokan, who is a record-holding hot air balloonist, had an opportunity to take a flight in a conventionally shaped blimp. During that flight he realized that the cigar shape and fins on the conventional airship require a large area to moor it to a mast so it can weathervane with the wind. It also requires a very large crew of ground handlers to dock and depart.
Thus began Hokan's dream of a better airship. It has been a long road, but what Hokan has achieved is truly exciting, and a perfect example of what a homebuilder can do.
This modern version of the airship is considerably less costly to design and manufacture, and it takes advantage of leading edge aerospace engineering, as well as incorporating state-of-the-art materials and fabrications.
The spherical airship has no preferred direction in the wind. Between flights, the airship is simply secured to the ground. Specialized ground equipment is not necessary.
The airship requires a ground crew of two people. This is a direct result of the excellent low-speed maneuverability and ability to maintain full directional control at any speed from zero to full speed.
Engines are mounted on the envelope, fully removed from the passenger cabin, which is internal, (no gondola) and quiet.
The spherical airship is a purpose-built design for advertising and sightseeing.
Lots of folks here in Georgia thought maybe it brought us some luck since our Atlanta Braves won the series. Who knows? One thing I do know, we sure had fun while the ship was here, and I'm betting Hokan Colting has hit a home run with the spherical airship.
The airship in flight over the Georgia countryside.
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