Margo Chase, graphic designer and founder of the Chase Design Group, died Saturday in a plane crash in Apple Valley, northeast of Los Angeles. She was 59.

Also an accomplished aerobatic pilot, Chase was practicing sequence in an aircraft when the accident occurred, according to a statement from International Aerobatic Club President Mike Heuer. Patrick Dugan, Chase’s husband, watched from the ground as her plane crashed. She reportedly died upon impact.

With her distinct style, Chase was known for designing the logo for the popular TV shows Buffy the Vampire Slayer, Angel and Charmed. She also worked on branding projects for Target as well as typography design for high-profile clients including Cher, Prince, Madonna and Selena.

Chase Design Group

Founded in 1986, Chase Design Group became a global brand design firm with offices in Los Angeles, New York, Chicago and the UK. The award-winning group worked on brand strategy, corporate and brand identity, package design and retail environments for clients including Procter & Gamble, PepsiCo, Nestlé and Campbell Soup Co. Other clients included ESPN and Microsoft.

“Everyone in the Chase Design Group family has been touched and inspired by Margo’s creativity, generous spirit and love for design,” President Chris Lowery said in a statement. “We will all miss her brilliance and incredible energy but will carry her vision for the organization forward as she would have wanted. All of us here at Chase send our heartfelt condolences to her husband Patrick Dugan and the rest of her family.”

Admirers of her work have taken to social media to send their condolences, calling her “a true legend” and “an iconic designer.”