[samste]

How to make an Edf or Prop Planes Quieter

The More blades on an Edf is a step closer to a quieter Edf
EG , 3 blade Edf Will be Louder than a 5 Blade Edf
Here is a Clip showing the Difference between a 5 Blade Edf and a 10 Blade Edf

http://www.youtube.com/watch?feature=player_embedded&v=qvWGDk1htjw

If you are looking at a Edf to be quiet look to buy an edf with more Blades, a 7 blade edf balanced is quiet and powerful.
Changesun do 10 Blade Units which are quiet and do hae a nice sound similar to Turbines.
Keep in Mind with more blades on an Edf the kv of the Motor will need to be Reduced .

EG , 5 blade edf with a 4000kv motor may draw 50 amps changing the unit to a 10 blade will increase it to 70 plus amps.

A Balanced Edf is the most Important Thing as a well balanced Edf will have minimal vibration which will reduce noise by a huge amount.
An unbalanced Edf will sound likes it crying for help while a balanced Edf will have a Smooth Sound.

Balancing a Edf is Similar to Balancing a Prop Blade heres a clip on Balancing a Edf that may help

http://www.youtube.com/watch?v=iath3xkDiqI&feature=player_embedded

here is a thread with some Info and Pics
http://forum.rcflyingclub.com/showthread.php?tid=88&pid=13261#pid13261

Balancing a Prop Blade is Similar, here is one of many Propellor balancing that may help you, you can do a basic balance making both sides level or go in depth and
rim balance for a perfect balanced blade.

A balanced Blade is very important when you have a high kv/rpm pushing it you will notice more noise and vibration of a unblanced prop in a high kv /rpm setup compared to a low kv/rpm setup.

http://youtu.be/N02NHYrpA0g

http://youtu.be/1JuSujZ_pFw

Reducing noise of a Pusher Prop can be done by reduing the Kv of the motor and increasing the prop size.

Eg
2200kv motor pushing a 6x6 prop which is a Stryker Q setup can have its noise reduced by reducing the kv down to 1450kv and a 8x6 prop or can be reduced by reducing the kv down to 1800kv with a 7x6 prop
Thrust will be increased and noise will be reduced, you may lose a little top speed of the original setup.

Other Things To look at are -
Motor mounts are Secure, Different Props Too can be Noisy, and Cowling can be noisy if not secure.

Any further information in regards to making our Planes Quieter please Contribute to this Thread

Steve