aircrack-ng is a set of tools for auditing wireless networks. It’s an enhanced/reborn version of aircrack. It consists of airodump (an 802.11 packet capture program), aireplay (an 802.11 packet injection program), aircrack (static WEP and WPA-PSK cracking), airdecap (decrypts WEP/WPA capture files), and some tools to handle capture files (merge, convert, etc.).
You can download it from the following link: https://packetstormsecurity.com/files/download/46060/aircrack-ng-0.5.tar.gz
Source: https://packetstormsecurity.com/files/46060/aircrack-ng-0.5.tar.gz.html