Is it possible to reinstall iPadOS 15 on iPad Air 2 without totally erasing the iPad? (opens in new tab)

I know that macOS can be replaced on my MacBook without erasing all the data and starting from scratch\. I've been unable to find any information about doing this with my iPad Air 2 \(with iPadOS 15\)\. Is it possible, or must the iPad be totally erased to refresh the OS?