Hendrickson, a global manufacturer and supplier of suspension systems and components for commercial vehicles, will back the team’s #44 entry for the 107th running of the Indianapolis 500.
Legge, 42, is one of nine women to have competed in the Indy 500, but last raced there in 2013.
Since then, she has made a name for herself in the IMSA SportsCar Championship, scoring four wins for Michael Shank Racing (now Meyer Shank Racing) in the GTD category, racing an Acura NSX.
She finished second in the championship in 2018, and now competes in the Gradient Racing NSX, in which she finished fourth in last month’s Daytona 24 Hours.
Legge will join RLL full-timers Graham Rahal, Christian Lundgaard and Jack Harvey in May, and has previous with the team having earned a pole and a win for the squad in the Jaguar I-PACE eTrophy series that formerly supported Formula E.
Legge’s two outings at Indy came with Dragon Racing in 2012, and with Schmidt Peterson Motorsports in 2013.
Her top-line US open-wheel career stretches back to 2006 when, on the back of three wins in the Atlantic Series, she graduated to Champ Car with PKV Racing. In total she has made 39 Indy car starts with a best finish of sixth.
“I am thrilled to be back at Rahal Letterman Lanigan Racing for the biggest race in the world, the Indy 500,” said Legge.
“Bobby [Rahal] gave me my first chance to win races for the team in the Jaguar I-PACE series a few years ago and it feels like a homecoming of sorts to be back with the team, especially seeing as I’m also very proud to be back with HPD in IMSA, and now in the IndyCar Series.
“Racing at Indy with an Indy 500-winning team and with Honda is an amazing opportunity, and one I am very grateful for and intend to make the most of. I’m hoping I can learn from my teammates and team members, and transition smoothly back to open wheel racing for May. I can’t wait to get to work!”
“After more than a few attempts, I’m happy to announce that Katherine will join us in our Hendrickson Honda for the 107th running of the Indy 500,” said team co-owner Rahal, the 1986 Indy 500 winner and a three-time Indy car champion.
"“I’ve been a fan of Katherine’s for many years and know that, in the right situation, she can be competitive and figure into the outcome at the end of the race.
“She has driven for us before in the Jaguar electric program and won from pole in Mexico City and finished on the podium several times, so it is nice to have her back with us to work together at the Indianapolis Motor Speedway for the first time.
"I know she looks at this as a chance to show everybody what she really can do.”
RLL has scored two Indy 500 wins, in 2004 with Buddy Rice and in 2020 with Takuma Sato.