To add another reassuring voice, the A220 is arguably the most comfortable airplane in the skies right now. Delta has put it on its most competitive routes where they want to poach passengers from other airlines, which should tell you a bit about the experience onboard. It has brand new entertainment systems, a 2-3 seating arrangement that helps you get a row to yourself no matter what your family size is, and oversized and comfortable lavatories. If you’re familiar with other airplane types from history, it’s probably closest in size to the old DC-9, a reliable workhorse that you may have been on in the past.

I’d expect a quieter than usual takeoff and flight experience. Nobody can guarantee a smooth ride, but the aircraft won’t be a factor here - it should be just as stable as any other airplane you’ll encounter within the domestic US.

You may find it helpful to visit turbulenceforecast.com before your flight - on this site, current areas of known bumpiness are displayed. Rest assured your pilots will have access to this (and even better) data, and will be planning a safe course around as much bumpiness as possible - but knowing that it might be coming can be hugely reassuring because it doesn’t come as a surprise, at least for the nervous fliers I know personally.