Orville Wright , American inventor
said about Efficiency...
"No data on air propellers was available, but we had always understood that it was not a difficult matter to secure an efficiency of 50% with marine propellers."
- Orville Wright Read all Orville Wright quotes, or find out more about Orville Wright
"No data on air propellers was available, but we had always understood that it was not a difficult matter to secure an efficiency of 50% with marine propellers."- Orville Wright