Republic XF-91 Thunderceptor
The Republic XF-91 Thunderceptor (originally designated XP-91) is a mixed-propulsion prototype interceptor aircraft, developed by Republic Aviation. The aircraft would use a jet engine for most flight, and a cluster of four small rocket engines for added thrust during climb and interception.
Source: Wikipedia — Republic XF-91 Thunderceptor (CC BY-SA 4.0)