The hydrogen fuel tank also functions as the vessels ballast having {HEAD ~ adjustable draft} depending upon {TAIL ~ its fullness} 
depending upon
The hydrogen fuel tank also functions as the vessels ballast having { HEAD ~ adjustable draft } depending upon { TAIL ~ its fullness }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL