Complex sentence: For mission safety, weeks before the manned mission, an LK-R unmanned L3 complex and two Lunokhod automated rovers would be sent to the Moon, to work as radio beacons for manned LK, with the LK-R used as a reserve escape craft.
Split into simpler sentences: For mission safety, weeks before the manned mission, an LK-R unmanned L3 complex and two Lunokhod automated rovers would be sent to the Moon. They worked as radio beacons for manned LK, with the LK-R used as a reserve escape craft.