which plane for o.s. fp25

[Derrick Kerr]

i am looking for a good stunt plane for my fp25. i noticed there are alot of planes designed arounf the fox 35 , how does the 25 compare power wise with the 35.

[Steve Holt]

Derrick,
I'm not sure what your experiece level is nor what you are looking for in a "stunt" airplane.  I use both FP20s and 25s on a variety of airplnes.
1.)  For basic sport and learning to fly stunt try a Ukey 35
2.)  Next level is a Sig Skyray 35
3.)  For a full fuselage airplane, RSM has 2 great kits: Mackey's Bluebird and Goyet's Feno

There are lots of old "Fox 35" size airplanes that will fly fine with an FP25.  RSM kits the Ringmaster which is a good match for your 25.

Steve

[wwwarbird]

 If you are looking to get in the air quickly, get an ARF Flite Streak. Ditch the mono-wheel gear, add Sig Fazer landing gear and a new fuel tank, and go fly! Or, get an ARF Brodak Super Clown and you can have a flap plane. If you want to build something (please  ) there is a long list of candidates...

 Whatever you decide, HAVE FUN!

[Alan Hahn]

I agree, the fastest and cheapest with an FP25 or LA25 would be the TF Flite Streak Arf. It really goes together fast, and with a low vibration engine, the fuse will be ok. I fly mine with a Fox 15BB and a 7-4 prop on 52 foot lines. It is a nice "first flyer" of the year for me.
Also if you are "re-aquainting" yourself with UC, the Ukey 35 is a good strong (as in bounce-ability) choice too. See the other thread for where to get it.

[Brett Buck]

i am looking for a good stunt plane for my fp25. i noticed there are alot of planes designed arounf the fox 35 , how does the 25 compare power wise with the 35.

   Significantly more effective power with a 25FP. I would suggest any of the common "35-sized" profiles, like the Twister or Banshee. Replace the spray bar with one from a Supertigre, and use a 10-4 prop. Get several different types, including wood props, and see which one works best. Use the stock muffler, and set the engine peaked out lean, then back off 6-7 clicks or so until you hear a substantial drop. You want a "medium-rich" 2-stroke.

    Your biggest problem will be finding  prop that lets you run in a constant medium-rich 2-stroke in flight without generating too much speed. If you can get about 4.8-5.0 second laps in a constant medium 2-stroke you are all set. If it just wants to go too fast, try a different prop, or put on a Bru-Line air filter with the light tan element.

   One of the better-flying airplanes I have ever flown (probably top 20 all time) was a modified Twister with a 25FP/10-4 Rev-Up, running bone stock (including the muffler), with only the change to an ST51 spraybar.

     Brett

[Leo Mehl]

i am looking for a good stunt plane for my fp25. i noticed there are alot of planes designed arounf the fox 35 , how does the 25 compare power wise with the 35.

Ask Pat Johnston. He flew a full blown Nobler with a 25 FP. He has the answer. Or a Arctic Fox. Designed for Fox 35 but plans drawn for OS 25 LA I have plans.

[Brett Buck]

Ask Pat Johnston. He flew a full blown Nobler with a 25 FP. He has the answer.

   Actually, Pat's airplane had a strong tendency towards the "too much power" end of the spectrum!

     Brett

[Andrew Hathaway]

The 25FP has quite a bit more power then the Fox 35 but it's run characteristics are much different.  I ran one on a slightly scaled down Magician, a box stock TF Flite Streak (not arf), a modified Flite Streak, and a Nobler ARF.  It'll do the same job as the Fox 35 but it does it differently.  I was never really happy with the 25fp on any of the planes I used it with.  It was too much for the profiles, and the ARF Nobler never really cooperated.

[Brett Buck]

The 25FP has quite a bit more power then the Fox 35 but it's run characteristics are much different.  I ran one on a slightly scaled down Magician, a box stock TF Flite Streak (not arf), a modified Flite Streak, and a Nobler ARF.  It'll do the same job as the Fox 35 but it does it differently.  I was never really happy with the 25fp on any of the planes I used it with.  It was too much for the profiles, and the ARF Nobler never really cooperated.

   The trick is in the propellor - you can control the speed, to a large extent, with the pitch.

     Brett

[Leo Mehl]

Some flyers had these engens retimed for a 2-4 break, however I never heard any reports on how well the ran after the redo. The La seems to be a little more mild which really takes it out of the Fox 35 class of stunt motors. The La does run great on a profile.

[Brett Buck]

Some flyers had these engens retimed for a 2-4 break, however I never heard any reports on how well the ran after the redo. The La seems to be a little more mild which really takes it out of the Fox 35 class of stunt motors. The La does run great on a profile.

     On the former, the conversions I have seen were like traditional 4-2 break 25s - more than an OS20-s, less than a OS-30s and much less than a Fox 35. But obviously, I haven't tried or seen every single conversion. As far as LA25's go, they seem to be less powerful than a 20FP and don't run as well, and they are significantly less powerful than a 25FP. I wouldn't go for a LA25 in a Twister, at least not with the same sort of run.

           Brett

     

[Will Davis]

I would vote for a Sig Skyray or a Ringmaster  with stock FP25 . Good reliable power . LA25 will work too , but less power, but still plenty for the smaller planes , especially if they get a little heavy

Will Davis

[Brett Buck]

I would vote for a Sig Skyray or a Ringmaster  with stock FP25 . Good reliable power

 
     I tried the 25FP on the Skyray, and it was pretty good - a little hard to keep at a reasonable speed. The Ringmaster is a *bullet* on a 25FP. The 20FP, with the engine set properly with a 9-4APC, pulls it around at well under 4 seconds a lap on 60 ft lines. The 25 is even faster. You can get by for a while by needling it down, but it's 4-stroking throughout. That's not a stable situation - it will be OK 3 times out of 10, but the other 7 times it will run away (i.e. run like it was intended to)  and end up at 3.5 seconds a lap.

       Brett

[Leester]

The RSM Mark 1 at 42" span and 462 sq's would sound pretty good ?

[Terry Bolin]

How about the "Hole Shot" plane that AMA is doing across three issues?. I have the plans and it look like a fun build  Bob Hunt is writing the build articles.

[Richard Grogan]

Ringmaster. Or, a Ringmaster instead.

[Leo Mehl]

     On the former, the conversions I have seen were like traditional 4-2 break 25s - more than an OS20-s, less than a OS-30s and much less than a Fox 35. But obviously, I haven't tried or seen every single conversion. As far as LA25's go, they seem to be less powerful than a 20FP and don't run as well, and they are significantly less powerful than a 25FP. I wouldn't go for a LA25 in a Twister, at least not with the same sort of run.

           Brett

     

The LA 25 powers a twister a lot better than a fp20 any day. This I have seen. It also powers a Skyray better than a FP 20.This I can assure you.

[john e. holliday]

Derrick,  I am going to jump in here and say there has been some good stuff stated already.   I am also going to say that any plane designed around the Fox 35 Stunt would or should fly great with the OS FP 25.  I have my OS FP 25 on a "Sweet Sweep", a 50's style combat plane.  Did have it on a "Skyray", but, couldn't figure out the tank problem until I put another engine on the plane.   Later, DOC Holliday

[Steve Scott]

I've been flying a U-Key 40 with my FP-25 for several years.  I also have the Flite Streak ARF but the FP-20 seems much better suited.  These two combinations are ideal - I can't think of how possibly to improve them.

I've also flown a Fancherized Twister with the FP-25.  It did OK but I'm tempted to refit an LA-40.  It's not so much engine power as the size of the prop.  A 10.5 x 4.5 seems ideal to pull the Twister around but is a bit too much prop for the FP-25.

We also tried the ARF Primary Force with the FP-25 but upped it to a Brodak 40.  My son likes the added power of the Brodak.

[Steve Scott]

Some flyers had these engens retimed for a 2-4 break, however I never heard any reports on how well the ran after the redo. The La seems to be a little more mild which really takes it out of the Fox 35 class of stunt motors. The La does run great on a profile.

I sent a Magnum 25GP (a clone of the OS FP-25) into an engine builder to "retime" it to a more traditional stunt run.  I've never been able to get the engine to run at all now.  My FP-25 and many FP-20s were given the BBTU treatment (stock everything and an APC 9-4 prop) and they run wonderfully.