dhal22

my ultrasport 60 has an OS .61 RF with an enclosed pipe in the canopy. It is eerily quiet. and the pipe has a silicone tube exiting the bottom of the fuse so no oil residue. it can be done.

grcourtney

My Feedback: (1)

A .91 4c on a standard muffler is louder than my .61 2c on the pipe. I can see that statement being true if the pipe is not a muffled pipe.


Gary

bem

My Feedback: (1)

Hi,

Could You tell us the main steps involved You made for silence a .60-.61 with tuned pipe? I'm sure it could be helpful also today (Maybe start a new thread if You think it is to much off topic in this thread).
- I know the air intake on carburator could be silenced with a "muffler" type thing.
- You could "soft" mount the engine with rubber holders.
- Not tune the pipe (but why use a pipe then).
- Cut some of the propeller tips since they make noise and contributenot much to thrust anyway.
- Use a long stroke 2-strokeengine(usually) to use larger props that do not need to rev as much and therefore give less noise.
- Build in the pipe in fuselage and do some silencing on the pipe arrangement.

More?

/Bo

Sport_Pilot

That's not my experiance, a plane of that size will require much more than $50 in batteries. Although reviever batteries ast 5 years or more, the heavy load on electric motor batteries last about a year. Unless you don't fly that much or are satisfied with much shorter flights, and don't mind waiting for them to charge.

I don't think those flying pattern back then would have wanted them to be that quite, just less noisey.

Sport_Pilot

My club limit is 98 Db, which is very doable with a silenced tuned pipe.

AndyKunz

Correct, but it will also require way more than $50 in fuel to fly a big plane as much. My point is that motor + battery costs and engine/pipe + fuel costs tend to be about the same (batteries are probably still a little more expensive) by the time the battery is done. It's a matter of when you pay for them - up front (for several years of flying) or pay-as-you-go gallon by gallon. In the end, you'll have pretty darn close to the same amount of money wrapped up after a couple years of flying.

And yes, taking care of batteries (not storing charged, not over-discharging, not over-charging, not over-heating, etc.) is important to battery longevity.

Another good point is the difference between sport and competition flying. I fly a lot, but it's ALL sport flying, so I don't have to push my equipment to the limit nor do I have to worry about a few percent of lost power. Perhaps that viewpoint is what really makes the difference.

It's interesting, though, that electric is growing in the competitive C/L Stunt segment. The consistency of performance was one of the points that was made to me by one of my friends who competes there. No CG changes, no needle changes, etc.

I have to agree with that. And modern noise-control is definitely a good thing.

Andy

hairy46

My Feedback: (1)

Right now we have mostly glow some gas and some electric guys at our field, And to me we can share the same air space not a problem, The thing I notice on a pretty regular basis is the lipo batterys puff out so far they look like they are going to explode! And hearing well that one's garbage now! Honestly I have no interest in electric! one reason the batterys just do not seem reliable, I would miss the noise here the noise is really not much of a problem, I love tinkering with the glow engines and I would miss the smell of the glow fuel! Pattern planes to me need a glow engine up front to be the pattern plane I remember! Where there is a problem with noise then I reckon you got to do what you got to do to fly!

kochj

Ditto!!...................
I would like to see a setup like that....
I

kochj

I think the main thing is the "type of noise" that comes out of the plane...

4-strokes could be equally the same dlbs out of the exhuast, yet the 2-stroke sound, seems to be more irritating that the
4-stroke sound.

Prop noise is also a issue...
A two stroke (especially the .60 and less) require HIGH RPM to get the power out of them...7,000 4-stk vrs. 13,000 2-strk RPms or around there...
THis then equates to LOUD PROP noise.
Which can be Very irritating to home owners....


ALSo....

Muffled and Quite Pipe, is a BIg difference in sound, price, and performance.

I have a MUfled pipe for my OS 1.20 AX swinging a 17x6 APC 10,000 RPM's on the ground.
Much louder than my saito 1.25 w/ a apc 16x6. Runs less RPms as well though...


The Quiet pipes are great, but exspensive to make and pricey... 150$ Vrs 75$ for a Muffled pipe...
These prices are for the 15-26cc size though.
A Muffled Tuned Pipe is an un-muffled tuned pipe with a muffling can added over the back cone.
An un-muffled Tuned Pipe is a two-cone chamber with out any restrictions other than the back cone and the end stinger.

A Quiet Tuned Pipe or a Single Quiet Tuned Pipe is a chamber with baffles that tune the system and quiet the exhaust. A Quiet Tuned Pipe is quieter then a Muffled Tuned Pipe. A Double Quiet Tuned Pipe, as seen at the bottom of the Marine Tuned Pipe page, is even quieter and can be used on airplanes.

(Macs website)

Sport_Pilot

You just buy a silenced or quite tuned pipe! Though a three blade prop would also help.

http://macspro.com/tunedpipes.asp

bem

My Feedback: (1)

Sport_Pilot,

Good information - notice that Hangar 9 in their accessories list for Phoenix 7 ARF has a MAC "Muffled" tuned pipe listed (MAC1250). So keep that in mind - if you want or need a quiter pipe on that plane buy the"Quiet" tuned pipe instead (orthe "Double Quiet" tuned pipe).

/Bo

A Quiet Tuned Pipe or a Single (Q)uiet Tuned Pipe is a chamber with baffles that tune the system and quiet the exhaust. A Quiet Tuned Pipe is quieter then a Muffled Tuned Pipe. A Double (Q)uiet Tuned Pipe, as seen at the bottom of the Marine Tuned Pipe page, is even quieter and can be used on airplanes. Most of the Single (Q)uiet Tuned Pipes, shown on this page, can be made in a Double (Q)uiet version

Sport_Pilot

You will still have the problem with prop noise, but the quite pipe should be well under 98 Db which would be enough for me. But a three blade prop would bring the noise down further, especially if it loads the engine slightly more than the two blade prop.

kochj

I will have to post this in the engine forum, but I have had a hell of a time running my piped glow engines of late...

I have the muffler pressure tap midway on the pipe, but it seems this isn't a reliable method.
I may have to tap the header directly off the engine.

After pan caking my Reactor in the 1st 2-min of the flight...Due to dead stick I have
had ENOUGH, of 2-stroke engines and pipes.
I even spent couple of tanks on the feild making sure it was reliable....Problem was, I didn't run the WHOLE tank.
I would only run 3/4 of a tank, and refuel, thinking the problem solved, when it reared up @ 1/2 tank....
Be at mid throttle, go to high, "rrRRRAAppaHh"
That was it...
...ERRRRRggggg[:'(][>:][>:][>:]

2nd plane in 1-week due to lamo, mistakes...

69"yak.... WING departed in a spin, due to the screws vibrating loose!.
And now the reactor, with a ST .51 piped.

I have had enough of these glow engines, in general....

I would like to see these with an ignition and or gasoline with a pumped carb..

Perhaps, I have to run pumps when I have a pipe on...
I don't want to run WOT, all day....

It will piss the neighbors off completely...
I have several NIB 4-strokes, so that is where I am going with these things...

dhal22

kochj, your post is like your reactor. a bit scattered.

R_G

My Feedback: (1)

Sounds to me like it could be tank/clunk/pickup issue. Just a possibility, something to check if you haven't already.

Jon Wold

The factor that most affects noise is prop size because the prop dictates the RPM. It's also the cheapest way to reduce noise :-)

To silence a piped .61, here's the list of tricks I know of:
- Prop: no less than 12x11, get the RPM way down (use long stroke engines)
- Tuned pipe: Use a three-chamber pipe. I love the Hatori #650 (Use #700 for long stroke engines). Bolly pipes work also
- Tape the pipe. Seriously. Gaffa-tape it the whole thing, dumb it down. It works.
- Eliminate intake noise by taking air via a soft tube into the fuselage (drill a hole in the firewall and route the carb air from there)
- Prop noise - APC is pretty good. I think carbon and wood props are louder but that may be just me
- Soft mount the engine and pipe

stuntflyr

Since the Phoenix has an exposed pipe these are excellent suggestions for it. Thanks Jon Wold.
Chris...

playntraffic

what is the latest on the release?

rv7driver

My Feedback: (105)

end of August now.

klhoard

My Feedback: (10)

<entering the box. . .>
.
.I heard they are being shipped in the same container as the 2M Vanquishes. . . .
.
.
<exiting box.="" the="">.<exiting the box. . >
</exiting>

kochj

Lol....slightly funny... BUT doesn't apply here...
H9 Actually shows the plane (finished) and gives a backorder option.., and gives a reasonable arrival date....
(not, sometime in the near future)

Did you really need to bring that up..??
It's like BOOST tab, I mean "BOOB TAPS"...

klhoard

My Feedback: (10)

yes, best installed with "TITBOND" aliphatic resin glue. . .
.
OK, I'm now going to report myself to Handglider the Moderator. . .
.
</exiting></entering>

dhal22

easy Keith. we don't need 2 Dutch posters here. one is enough.

klhoard

My Feedback: (10)

. . .
.

Bijan999

My Feedback: (2)

Guess I've been out of the loop but just saw the advertisements about the new Pheonix 7 ARF. This is so awesomel! My dad had a Pheonix 7 around 25 years ago but he never built it. I actually wrote Mr. Lowe a letter when I was about 10 years old asking how to build it and he responded! What a great guy to entertain a 10 year old kid with silly questions about how to build one of his planes. Anyways, I ended up owning a Pheonix 9 a few years later, there is nothing like an old school pattern plane.

I'll have one of these for sure