Consider the almost impossible task contestants in the Team America Rocket Challenge were asked to accomplish.
First, engineer, design and build a model rocket weighing no more than 1,000 grams that will ascend to an altitude of 825 feet. That may sound easy, except for this first catch: No less than 825 feet, and no more, either.
Next, engineer, design and build a capsule carried by the rocket that will hold a large raw chicken egg. The capsule must land on the ground without any cracks in the egg. Catch number two: The capsule must remain aloft for at least 40 seconds, but for no more than 45 seconds.
Catch number three: No parachutes allowed.
A four-member team from Templeton High School in California, sponsored by Cubic Corp., was well up to the challenge. The team was among only six in the state to qualify for the finals, held May 15 in The Plains, Va., and they did it with almost a perfect score: Their rocket reached 823 feet before heading back to earth, and the capsule remained aloft for 41 seconds.
Among 669 teams competing, only a handful managed to match that performance, said Jill Southern, an engineering teacher. It is the third year Cubic, headquartered in San Diego, has sponsored Templeton’s team.
Southern said she is convinced the annual contest is invaluable in getting students interested in science, technology, engineering and mathematics, known as the STEM subjects. “I really think that when you add on a level of competition and a practical application, the kids get way more involved,” she said.
“I think the real story is the achievement of Jill Southern, a teacher in a little school in rural California who has coached a team into the national finals for three out of four years,” said Jack Liddle, Cubic’s vice president of legislative affairs.
So how do you get a rocket and capsule to do the things required by the contest? While designs with multiple rocket engines, electronic control systems and other complexities are allowed, contest organizers warn that more components means more things that could fail. They stress an engineering maxim: The simplest design that works is best.
The first steps are all on a computer, using a program such as RockSim that allows users to design rockets and run simulated launches, said Chris van Harmelen, 16, Templeton’s team leader.
That will get you in the ballpark, Van Harmelen said, but lots of trial launches are needed. Removing or adding grams of weight is the way his team zeroed in on the 825-foot altitude mark, measured by a small altimeter carried in the rocket. The team used a 10-inch wide 100-inch long Mylar strip to slow the descent of the capsule.
But like most things in life, even accurate simulations and flawless trial runs do not guarantee success. Some luck is needed, too.
Rocket motors can vary up to a 10 percent in thrust, Van Harmelen said, which means maximum altitudes can do so as well. Significantly more or less wind can affect how long a capsule remains aloft.
Templeton’s launch in the contest was among the best, reaching 815 feet, 10 feet shy of perfection. But high wind pulled the payload capsule upward, keeping it aloft for 59 seconds, 14 more than the maximum, reducing the team’s points. Templeton finished 29th in the 100-team field.
Van Harmelen, who said he plans to pursue “some sort of engineering” when he goes to college, agreed that the contest helps instill STEM.
But he had a simpler explanation for getting involved.
“It’s just fun,” he said.