But aren't these L/D numbers calculated for a theoretical case where there is no wind? What kind of L/D ratios would you see for helicopters, planes and blimps given a 20 knot head wind?
Sure, I don't doubt a blimp is more efficient when the wind is blowing it to where it wants to go, but what happens when the wind doesn't cooperate?
EDIT: yes, the Wikipedia page states that L/D numbers are usually presented as graphs, because they are dependent on speed. This means that without knowing the wind speed the blimp is facing, especially given it travels at a lowly 35 MPH, you can't really calculate an L/D number. For the helicopter and airplane, the wind matters less as they are going much faster.
Sure, I don't doubt a blimp is more efficient when the wind is blowing it to where it wants to go, but what happens when the wind doesn't cooperate?
EDIT: yes, the Wikipedia page states that L/D numbers are usually presented as graphs, because they are dependent on speed. This means that without knowing the wind speed the blimp is facing, especially given it travels at a lowly 35 MPH, you can't really calculate an L/D number. For the helicopter and airplane, the wind matters less as they are going much faster.