Call for proposals on rotor blade scintillation
The UK's Ministry of Defence is calling for research proposals on helicopter rotor blade scintillation.
Scintillation, also known as 'the halo effect', occurs when particles stirred up by the rotor downwash interact with the blades. This is a particular problem in sandy or dusty environments. Little formal research has been conducted in this area, but possible causes include triboluminescence, chemiluminescence and electroluminescence.
Proposals are sought to investigate the physics of this phenomenon and how to eliminate it.