| Projected Blade Area & Developed Blade Area | |||||||||
| Formulae | |||||||||
| Ap/Ad = 1.0125 - ( 0.1 x Pitch ratio ) - ( 0.0625 x ( Pitch ratio squared ) | |||||||||
| 51 | Developed blade area required | ||||||||
| 0.477 | Pitch ratio (P/D) | ||||||||
| 0.951 | PBA : DBA ratio. | ||||||||
| 53 | True blade area sq/in | ||||||||
| Projected blade area is the "apparent" area as seen from end on. | |||||||||
| Developed blade are is the true blade area. | |||||||||