Tuesday was the first time Waltz faced lawmakers since mistakenly adding a journalist to a private Signal chat used to discuss sensitive military plans.
The incident, in which the pilots were safely recovered, marks the third time since December that an F/A-18 assigned to the carrier Truman has been lost.
Pete Hegseth reportedly created another Signal chat that included his wife and brother in which he shared details of a military strike on Houthis in Yemen.