Cluster House Goes Up
March 10, 2011 —An aviation event occurred over the weekend in the Southern California High Desert that had previously only taken place fictionally. A cluster balloon lifted a house into the sky, flew for about an hour, then landed 10 miles to the east on Saturday, March 5. Jonathan Trappe, who flew his cluster balloon at AirVenture last year, reprised the role of Carl from Pixar’s Up when he piloted the flying structure for a National Geographic TV show called How Hard Can it Be?, scheduled to begin airing in the fall.
To answer the question of the show’s title: pretty hard. Lift needed to raise the prefabricated 16-foot by 16-foot structure required assembly of the world’s largest balloon cluster to date (which Trappe said he verified). There were 283 8-foot cells (balloons), each requiring an entire tank of helium (291 cubic feet each) to fill, for a grand total of 82,353 cubic feet (2,300 cubic meters) of the lighter-than-air gas.
Those who witnessed Trappe float over the AirVenture grounds last summer will recall his 50-cell cluster balloon, which he flew for nearly 12 hours before coming to rest in Lower Michigan. The cluster house, however, was nearly six times larger – weighing in at about 2 1/2 tons. Volunteers spent 13 hours inflating the 283 cells. Both clusters shared the registration number N878UP.
Trappe estimated the amount of helium used in the cluster house could have taken him to Florida , but the proof-of-concept, made-for-TV flight lasted a little over an hour and reached 10,500 MSL (about 7,000 feet AGL). He took off from the desert airstrip Brian Ranch Airport (CL13), traveled due east about 10 miles, and landed.
“We weren’t really trying to go anywhere,” Trappe explained. “Our main focus was on making a flight that was one, safe; two, legal; and three, reflected well on our flying community. Those were my goals, as an EAA member and certificated pilot.”
The flight was scheduled for a 6 a.m. liftoff. At that time, however, the system was not providing sufficient lift. As the sun rose higher it warmed and expanded the gas, thus creating increased lift. Trappe also jettisoned 3,200 of the 5,000 pounds ballast, and by 7 a.m. the house began flying.
“It is clearly the strangest thing I have ever flown,” Trappe said. “But more than that, it may be one of the strangest things to have ever flown.”
One of the last things he did before lifting off was affix the “EXPERIMENTAL” placard, just below the N number.
“A little more experimental than most,” he joked.