HobbyKing.com New Products Flash Sale
 
Thread Tools
Old Apr 11, 2003, 02:52 AM
Trowelfaz
Guest
n/a Posts
OS .46FX Prop Size for GP Easy Sport

Hello,
I have an old GP Easy Sport coming in at about 6.5lbs, and am running an OS
..46FX on 15% fuel with a 11x6 wooden prop (coming in at about 12,500 RPM). I
get short take-offs, excellent hang time and great verticle performance (can
hang on the prop, pull back power, and when it starts to stall and torque
roll, re-apply power and keep climbing and hanging), but here in the US
Midwest, it slows considerably when flying into the wind. I have used a 11x5
and was able to tack it out to 12,900 RPM, but suffered performance. Would I
still retain the verticle performance and gain some speed with a 10x6 prop
or the like? I guess I could always buy a bunch of different sizes and try
them, but am simply looking for suggestions first so I don't waste time
trying every pitch in the various sizes.


Old Apr 11, 2003, 02:52 AM
Brad Lorance
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

sounds like you might want to go up in pitch. An 11 x 7 might be what you
need, but "pulling power" will suffer. I'ts hard to find the best prop for
what you want to do, but generally the bigger diameter/less pitch gives you
upline power, but the pitch gives you speed. You might also try a 12.25 x
3.75 APC prop for kicks, it is one of those pulling props but fun for torque
rolling and 3D stuff. On a side note, I don't think the 46FX will turn
anything more than an 11 x 7 very well. I think if you pitch up to that
one, you might be "maxed out". On another side note, I run 30% Cool Power
heli fuel in my 46FX and it really likes it. That will speed you up too,
but keep it rich.

Brad


"Trowelfaz" <trowelfaz@MAPSONhotmail.com> wrote in message
news:b6sldn0q1l@enews2.newsguy.com...
> Hello,
> I have an old GP Easy Sport coming in at about 6.5lbs, and am running an

OS
> .46FX on 15% fuel with a 11x6 wooden prop (coming in at about 12,500 RPM).

I
> get short take-offs, excellent hang time and great verticle performance

(can
> hang on the prop, pull back power, and when it starts to stall and torque
> roll, re-apply power and keep climbing and hanging), but here in the US
> Midwest, it slows considerably when flying into the wind. I have used a

11x5
> and was able to tack it out to 12,900 RPM, but suffered performance. Would

I
> still retain the verticle performance and gain some speed with a 10x6 prop
> or the like? I guess I could always buy a bunch of different sizes and try
> them, but am simply looking for suggestions first so I don't waste time
> trying every pitch in the various sizes.
>
>



Old Apr 11, 2003, 02:52 AM
Ted Campanelli
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

On 4/7/2003 4:00 PM Ted shuffled out of his cave and grunted these great
(and sometimes not so great) words of knowledge:

Try an APC 11x6 or 11x7. Their nylon/composite props are usually more
efficient than a wood prop.

> Hello,
> I have an old GP Easy Sport coming in at about 6.5lbs, and am running an OS
> .46FX on 15% fuel with a 11x6 wooden prop (coming in at about 12,500 RPM). I
> get short take-offs, excellent hang time and great verticle performance (can
> hang on the prop, pull back power, and when it starts to stall and torque
> roll, re-apply power and keep climbing and hanging), but here in the US
> Midwest, it slows considerably when flying into the wind. I have used a 11x5
> and was able to tack it out to 12,900 RPM, but suffered performance. Would I
> still retain the verticle performance and gain some speed with a 10x6 prop
> or the like? I guess I could always buy a bunch of different sizes and try
> them, but am simply looking for suggestions first so I don't waste time
> trying every pitch in the various sizes.
>
>


Old Apr 11, 2003, 02:52 AM
Faz
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

I run the CP 30% in my Heli and R/C cars, and have considered running it in
my plane.... Maybe I will.


"Brad Lorance" <lorance11@comcast.net> wrote in message
news:uxqdnY0gPb-TnQ-jXTWc3Q@comcast.com...
> sounds like you might want to go up in pitch. An 11 x 7 might be what you
> need, but "pulling power" will suffer. I'ts hard to find the best prop

for
> what you want to do, but generally the bigger diameter/less pitch gives

you
> upline power, but the pitch gives you speed. You might also try a 12.25 x
> 3.75 APC prop for kicks, it is one of those pulling props but fun for

torque
> rolling and 3D stuff. On a side note, I don't think the 46FX will turn
> anything more than an 11 x 7 very well. I think if you pitch up to that
> one, you might be "maxed out". On another side note, I run 30% Cool Power
> heli fuel in my 46FX and it really likes it. That will speed you up too,
> but keep it rich.
>
> Brad
>
>
> "Trowelfaz" <trowelfaz@MAPSONhotmail.com> wrote in message
> news:b6sldn0q1l@enews2.newsguy.com...
> > Hello,
> > I have an old GP Easy Sport coming in at about 6.5lbs, and am running an

> OS
> > .46FX on 15% fuel with a 11x6 wooden prop (coming in at about 12,500

RPM).
> I
> > get short take-offs, excellent hang time and great verticle performance

> (can
> > hang on the prop, pull back power, and when it starts to stall and

torque
> > roll, re-apply power and keep climbing and hanging), but here in the US
> > Midwest, it slows considerably when flying into the wind. I have used a

> 11x5
> > and was able to tack it out to 12,900 RPM, but suffered performance.

Would
> I
> > still retain the verticle performance and gain some speed with a 10x6

prop
> > or the like? I guess I could always buy a bunch of different sizes and

try
> > them, but am simply looking for suggestions first so I don't waste time
> > trying every pitch in the various sizes.
> >
> >

>
>



Old Apr 11, 2003, 02:52 AM
john alt
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

In article <Xtpka.402128$sf5.725674@rwcrnsc52.ops.asp.att.net >,
faz@MAPSONattbi.com says...
> I run the CP 30% in my Heli and R/C cars, and have considered running it in
> my plane.... Maybe I will.
>

Anything over about 15% is a waste on that engine if you haven't done
any mods to it.
Old Apr 11, 2003, 02:52 AM
Normen Strobel
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

Pull the baffle out of the muffler and you will gain 1000 RPM on that
engine. I believe if you shorten the prop and increase the pitch, it will
increase in speed but you will lose some pulling power.

"Trowelfaz" <trowelfaz@MAPSONhotmail.com> wrote in message
news:b6sldn0q1l@enews2.newsguy.com...
> Hello,
> I have an old GP Easy Sport coming in at about 6.5lbs, and am running an

OS
> .46FX on 15% fuel with a 11x6 wooden prop (coming in at about 12,500 RPM).

I
> get short take-offs, excellent hang time and great verticle performance

(can
> hang on the prop, pull back power, and when it starts to stall and torque
> roll, re-apply power and keep climbing and hanging), but here in the US
> Midwest, it slows considerably when flying into the wind. I have used a

11x5
> and was able to tack it out to 12,900 RPM, but suffered performance. Would

I
> still retain the verticle performance and gain some speed with a 10x6 prop
> or the like? I guess I could always buy a bunch of different sizes and try
> them, but am simply looking for suggestions first so I don't waste time
> trying every pitch in the various sizes.
>
>





-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 80,000 Newsgroups - 16 Different Servers! =-----
Old Apr 11, 2003, 02:53 AM
Mathew Kirsch
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

"Trowelfaz" <trowelfaz@MAPSONhotmail.com> wrote in message news:<b6sldn0q1l@enews2.newsguy.com>...
> Hello,
> I have an old GP Easy Sport coming in at about 6.5lbs, and am running an OS
> .46FX on 15% fuel with a 11x6 wooden prop (coming in at about 12,500 RPM). I
> get short take-offs, excellent hang time and great verticle performance (can
> hang on the prop, pull back power, and when it starts to stall and torque
> roll, re-apply power and keep climbing and hanging), but here in the US
> Midwest, it slows considerably when flying into the wind. I have used a 11x5
> and was able to tack it out to 12,900 RPM, but suffered performance. Would I
> still retain the verticle performance and gain some speed with a 10x6 prop
> or the like? I guess I could always buy a bunch of different sizes and try
> them, but am simply looking for suggestions first so I don't waste time
> trying every pitch in the various sizes.


It sounds like you've got the best prop for the job already. Dropping
to a 10x6 will get you more RPMs, but thrust and vertical performance
will suffer greatly.

Even though the plane looks like it's going slower nito the wind, it
really isn't. Relative to the air, it's flying just as fast as it does
when the wind is calm. If your airplane has an airspeed of 60mph in
dead calm air, it will have an airspeed of 60mph into a 20mph
headwind. To someone on the ground, it looks like the airplane is only
going 40mph. This happens to ALL airplanes, and there is no way around
it.

The only way to make the airplane go faster when the wind is blowing
is to make the plane go faster, period. However, you also want
vertical performance and maximum thrust. You can't have your cake and
eat it too, as the saying goes. A prop designed for maximum speed
won't have much thrust, and a prop designed for maximum thrust won't
have as much speed. On top of that, the Easy Sport is a draggy,
relatively slow plane. It may very well be that the airplane is not
capable of flying any faster than it already is, without adding a
larger engine. Then when you add a larger engine, you add weight.
Weight increases the wing loading, and makes the plane harder to fly.
Old Apr 11, 2003, 02:53 AM
Brad Lorance
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

You'll never make me believe that. It's all I use now, I had the 15% before
and there is a big difference.

Brad L.



> Anything over about 15% is a waste on that engine if you haven't done
> any mods to it.



Old Apr 11, 2003, 02:53 AM
Trowelfaz
Guest
n/a Posts
Re: OS .46FX Prop Size for GP Easy Sport

Hmmm. I have been getting 12,500RPM on the 15% fuel, and as a suggestion,
tried my 30% Heli fuel that I use in my Heli and Nitro cars. While still
slightly rich (and with the 11x6 prop) turned in 14,200RPM, and was able to
crack 15,600RPM when I leaned it out. Snow has grounded me, so I cannot say
what the difference during a flight will be.

"john alt" <johnaltDoesntneedSpam@charter.net> wrote in message
news:v94fkggeeii419@corp.supernews.com...
> In article <Xtpka.402128$sf5.725674@rwcrnsc52.ops.asp.att.net >,
> faz@MAPSONattbi.com says...
> > I run the CP 30% in my Heli and R/C cars, and have considered running it

in
> > my plane.... Maybe I will.
> >

> Anything over about 15% is a waste on that engine if you haven't done
> any mods to it.



 


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Prop size for a OS 48 four stroke Howemd Engines 1 Jan 15, 2007 02:51 AM
Best Brushless Combo Prop Size For NSP Filip 400???? saint152 Electric Sailplanes 4 Sep 22, 2002 12:29 PM
Recommended prop size for S280? Danny Troy Power Systems 5 Jul 12, 2002 10:17 PM
Prop size for a belt drive help? Duane Power Systems 2 May 15, 2002 08:31 PM
Prop size. for 2x4 glider Dandi6065 Power Systems 0 May 11, 2001 08:30 PM