I've been keeping my mouth shut on the other thread but, sorry. Enough. Lighter than air craft are an aberration belonging in the past where they belong. We have the technology to produce massive aircraft that handle like gliders. We have seen lifting bodies that pierce the atmosphere at many Machs and land on conventional runways. There is a reason why we are legally bound to avoid lighter than air vehicles in flight. That reason is that they are unable to maneuver themselves in a controllable manner. Noble but pointless. WW2 barrage balloons were a magnitude of times more effective and they were little more than enlarged children's toys. "Long range oceanic patrol." Pah. Cargo. The physics just doesn't work. Battlefield observation. Would you really want to sit in a basically uncontrollable airborne vehicle the size of a ship over hostile territory? Pack it up boys. Save your money. Elon Musk can send a payload into space and 5 times out of ten land the rocket vertically back on a bobbing barge.