I take it your not a helicopter pilot ? The air intakes are the least of your worries , especially on the 500 , virtually every turbine aircraft has intake screens , the 500 also has a particle filter which will even keep sand out . The blades aren't that tough , and unfortunately everyone who has read chicken hawk believes that you can cut down trees with main blades , you are correct blades have been hit by rounds , and luckily they have travelled through the blade missing the spar and leading edge , but agreed they would probably survive a drone strike to allow the helicopter to land , but the blades etc would still be scrap after that . If the helicopter is flying forward , it will hit the drone ( bird far more likely ! ) before the down wash hits it , down wash is on really relevant if it where hovering , but having suffered bird strikes and seen the damage they can do , being a soft object , compared to a drone , I think it's a very good idea to keep clear , for both parties !