There are also many native Japanese onomatopoeiae using an initial p sound. Interestingly enough, if we're at Pokémon, Pikachu's name is influenced by the onomatopoeia /pikapika/ which means to shine, sparkle or flash. But if we look at the original pronounciation of the Japanese verb 光る/hikaru ("to shine"), it would have been pronounced /pikaru/ in Old Japanese, so it looks like the onomatopoeia has re-established itself.

The same is probably true for the Japanese word for flag, 旗/hata - it would have been pronounced /pata/ which is suspiciously reminiscent of the onomatopoeia /patapata/, often used for thin pieces of material flapping in the wind.