Wonderful Picture of your Great Grandfather Cripple.
My Great Grandfather was also born in Germany (as well has his son and his son)
But mine is slightly younger than yours, he was born in 1902.
That one was my great grandmother's father. My great grandfather had the presence of mind to recognize the significance of a man born in 1872 flying on a plane and took this photo of GGGF.
I think that might be my great grandmother (his daughter) waiting at the bottom of the steps.