Interesting view of retracting the main gear, just at the end of the video. The bogies fold backwards to lie parallell to the main strut, and then the the whole gear swings backwards into the nacelle. Very nice engineering. Pity, that the testflight of the KLM top ended in a belly landing in a Welsh marsh in the 1950's, otherwise they might have flown with a Royal Dutch cheatline across the ocean.......