I was thinking this after I saw it on the ground, but it was probably difficult to estimate the size in the air. The father should have known roughly how much

I was thinking this after I saw it on the ground, but it was probably difficult to estimate the size in the air. The father should have known roughly how much it could lift, and I think I saw a statement that it could only life its battery pack. But he was probably willing to cast that evidence aside for the (erroneous) eyewitness testimony that it happened.