It is. It has stretched D9 undercarriage with special wide pads. They built it in 4 weeks in 1972. A Hopto 1900 hoe on a custom elevated pipe mount support with the tracks 35' wide to straddle the spoil pile followed it. There's pics. but unfortunately there doesn't appear to be any video of it operating which is a shame. Henuset also built 2 HD41 pipelayers that were the largest built at the time. Might still be.