Blackburn Mark
Well-Known Member
- Joined
- Sep 17, 2020
- Messages
- 112
Currently building a sub 70kg three axis (don't know if it can be done but an attempt is underway)
My assumption for propeller choice has always been bigger=better regarding efficiency....
During communications and attempt to order a 160cm ground adjustable pitch propeller from DT-Propellers, I have been advised that the Bailey 15~20hp motor will struggle to get up to "needle rom with a 160cm propeller".
(I think they may be using a standard drop down list of stock propeller, paramotor engine Re-drive compatibility)
DT-Propellers is attempting to look after me which is nice but the language difference is making it difficult to for them to objectively quantify any misconception I may have regarding my assumption that:
1) Its a pitch amusable propeller
2) I can machine any reduction ratio required (I am thinking between 1:3.2 and 1:4)
Am I missing something regarding the dark art of propeller theory?
My "assumption" is, despite being driven by 20hp instead of 50hp, I will gain the additional aspect ratio efficiency over a more standard 130cm as long as my re-drive and blade pitch choice allows me to sink the full 20hp into the propeller (allow it to reach max motor RPM//8000rpm)
Any information from anyone who can throw some light on the conundrum would be much appreciated.
My assumption for propeller choice has always been bigger=better regarding efficiency....
During communications and attempt to order a 160cm ground adjustable pitch propeller from DT-Propellers, I have been advised that the Bailey 15~20hp motor will struggle to get up to "needle rom with a 160cm propeller".
(I think they may be using a standard drop down list of stock propeller, paramotor engine Re-drive compatibility)
DT-Propellers is attempting to look after me which is nice but the language difference is making it difficult to for them to objectively quantify any misconception I may have regarding my assumption that:
1) Its a pitch amusable propeller
2) I can machine any reduction ratio required (I am thinking between 1:3.2 and 1:4)
Am I missing something regarding the dark art of propeller theory?
My "assumption" is, despite being driven by 20hp instead of 50hp, I will gain the additional aspect ratio efficiency over a more standard 130cm as long as my re-drive and blade pitch choice allows me to sink the full 20hp into the propeller (allow it to reach max motor RPM//8000rpm)
Any information from anyone who can throw some light on the conundrum would be much appreciated.
