"As a kid I had my own model helicopter," said Jenner shortly before he was to speak at the exposition.
However, it was many years later that his love for the miniature flying machines was rekindled by a Christmas gift from his son, Brandon.
"I think it was three Christmases ago my son, Brandon, was at a hobby store, saw the (radio controlled) helicopter for me and got it as a gift," the gold-medal decathlete said.
While many at the expo seemed to have a preference for model radio controlled airplanes, Jenner prefers the helicopters. In the last year, the Academy of Model Aeronautics member has amassed a fleet of seven copters, all of which are in working order.
Most recently, Jenner purchased a Goblin 770.
"That's one I really wanted and I just was able to buy it," he said.
When Jenner bounded onto the stage, he was greeted with cheers.
"Some of you may be thinking, `What's Bruce Jenner doing here without (his) family behind him?' I actually do things on my own," Jenner joked.
Denise Lee of Apple Valley was at the expo with her husband, son and grandson.
"This is something we de every year," Lee said as she stood watching her grandson, Nathan Lee, 5, build a model rocket with his grandfather. "This is Nathan's first time here."
Lee's son has had a life-long love affair with model radio controlled airplanes and has been a member of the Academy of Model Aeronautics for some time.
"We decided to come down all together and enjoy ourselves," she said.
Nathan's face lit up as his grandfather helped the 5-year-old build his rocket, saying he couldn't wait to fly it with his "Papa."
"This is the boys' candy shop," smiled Lee.
Standing in the center of the throng of people looking to buy or admire aeromodels was Carl Rankin of Woodland Hills, who held up what at first glance looked like a colorful and whimsical piece of modern art. But a closer look revealed it was a radio-controlled flying machine made out of colorful straws, packing tape and kitchen cling wrap.
"I call it the Jules Verne because a lot of people have commented it looks like something out of a Jules Verne novel," said the demo pilot for RC Trayman Co.
Rankin had just come from flying his Jules Verne in a separate room across from the main exhibition hall where Academy of Model Aeronautics members were allowed to demonstrate and fly their radio-controlled models.
It wasn't just flying machines on display. Near the rear of the showroom, one exhibitioner displayed a handful of model World War II tanks complete with drivers atop the large models.
"That's just amazing," said one man as he marveled at the detail that went into the tanks.
The three-day expo continues today.
Reach Beatriz via email, call her at 909-386-3921, or find her on Twitter @IEBeatriz.