air filter/screen-or not

[kiptone]

i would like some opinions on useing the air filter sold for for 50 size engines.will they restrict any air flow or not?

[WayneBrown]

yes they do, they are also a pain in the butt to service and at the end of the day are NOT worth the hassle.

[MartyH]

The system that comes standard on the Audacity Pantera doesnt seem to effect performance and it really doesnt need any servicing, certainly not often and is painless if it does. http://www.audacitymodels.com

[RAV50]

Any restriction will effect performance - how much, is relative to the benefit delivered.

If you fly in a dirty/dusty environment, then the benefits can outweigh the possible damage to the engine. But if you operate in a cleaner, less dusty environment, then the benefits can be marginal at best.

[MartyH]

http://www.geocities.com/mhammersmith/filter.jpg

The Audacity system is very good and has an almost imperceptable restriction to flow. The current version is a clear silicone tube and larger diameter dry foam element. Any filter is a good idea if you think about where the carb opening is located. Mounted vertically under a clutch, it's trying to ingest all that abrasive clutch dust. I only run filters on the Audacity Pantera's cause it's designed for that frame and the filter is right on top out in the open so very easy to service. It is specifically designed for their frame and the OS50 engine. If I could make this fit some of my other heli's, I'd be using it. I have not had a chance to check out the other filters but if you cant get them located out in the open, I can see where they would be a bear to clean.

[WayneBrown]

http://www.geocities.com/mhammersmith/filter.jpg

The Audacity system is very good and has an almost imperceptable restriction to flow. The current version is a clear silicone tube and larger diameter dry foam element. Any filter is a good idea if you think about where the carb opening is located. Mounted vertically under a clutch, it's trying to ingest all that abrasive clutch dust.
You've read one too many sales pitches, back away from the reading material, back away.. :):):)

Anytime you believe a manufacturers BS over common and shared experience, you need a wake up.
First, the FAN attached to the clutch cleans most of the air centrifugally BEFORE it gets to the carb.
Any additional positive air pressure the carb sees by being mounted inside a fan shroud is acting as a mini-supercharger, with some measurable gain in performance. The Audacity 'snorkel' does not avail you of that advantage, no matter how slight it may be.
If John Beech wants to advertise here, he's welcome to pay the fee and have something on the front page. He's even welcome to spout all the PR and pitches he wants, now getting anyone to believe it is another matter. ;)
Many of us have helped JB in some fashion over the years, and continue to hope the best for him in his business ventures. If he'd design and build a machine for the PILOT instead of the newbie He'd sell a lot more of them.

[kiptone]

I just have the little screen type ,to keep some of the junk out.Not the tube and filter that is in the pictures

[MartyH]

I am simply answering the question about whether anyone uses a filter on their helis and what they perceive their performance to be. This is the one I use. I am not John Beech nor am I promoting his helicopters. I own 12 nitro helis, 5 are Audacity models, 4 are Thunder Tiger and the others are other brands including a Knight 3D. I used the picture from his website because it was easy and clearly shows how they tackle the air filter question.

[RAV50]

Just an observation from the picture.

From looking at that picture, it seems to me that the long tube will end up restricting cooling air in the fan shroud from getting from the fan to the engine cooling fins. If one was to calculate the volume of airspace inside the shroud with it being in place, I will bet there is a substantial difference in shroud volume compared to other 5 size helis.

If I had that heli and did fly from a desert type of dusty field, I would just use a filter that fit directly over the top of the carb.

IMHO, that long tube is unnecessary "bling"...even worst, negative"bling", as it really degrades the cooling performance of the cooling system and adds unnecessary weight to the model. But I can see how it can be a marketing "tag" for the model.

[MartyH]

I have the EagleTree data logger which can prove cooling is not hurt. It was my first thought too but it has not been the case. I'll likley continue to use that system.

[skunkworx]

Hmmm....well around here, we have nothing but dirt!!!! So even at a small loss of power, would the filter or the screen make more sense? I run RC trucks and it's impossible to run without a filter, so I'm assuming that it won't really drag the heli down enough to make a gigantic difference. Limit it may do, but I'd rather have my motor last a few more flights than risk it.

[WayneBrown]

think this way: the heli spools up, and the downwash blows away from the mainmast.
Do you really need a filter?
You be the judge of whats best for you and your budget, however I suspect that you will have more maintainence issues with it.

[skunkworx]

Not to be argumentative Wayne, but the kind of dirt we have around here can find it's way inside of a sealed lightbulb! lol!!!

Well seriously, you do have a point. I hadn't thought of it that way. I have a pretty tough time keeping my 450 dust free, so a nitro might be a bit worse. I'll try it a few times with and without to see if it's a huge difference and decide from there. The screen sounds good for grass protection though

[maxadventure]

no one can make claims of increased or decreased performance without empirical data. I don't have that data for my .50 hyper at this time, but I have read a few that do, including Marty in this thread. I do have a significant amount of experiance force feeding engines for performance and I've learned a couple things.
Cool, clean air is good, dust laden hot air is bad.
I will ALWAYS run an air filter, especially if I can get a better air source. The key to not restricting flow is using a well designed system. Either off the shelf or you do it yourself. One of the reasons I picked up a Pantera was specifically because it already had a filter designed in, with a well designed flow. Honestly, I think the filter element itself needs help (too open, no oil to trap particles, not well attached), and I'll be replacing mine with a high flow filter from the world of 1/8 scale buggies. If anyone flys off any form of dirt, try running a q-tip in your fan shroud. I'd bet a barrel of Guinness it comes out grimy.

ps- a heli cooling fan does not equate to a Dyson.:DOH

[skunkworx]

Good point. The sand around here is pretty serious, so the filter will almost be a requirement. Even on my electrics, the dust buildup gets pretty bad after 2-3 flights so I can imagine what it would do to a gas motor. Another downside to my location is the heat. 120+ in the middle of the summer, so I'll probably have to go to night flying equipment to avoid all but getting heatstroke! (or simply put the helis away and take the boat out to the river :) )