okypolice

Hello..Mr Randy
I'm Oky from Jakarta Indonesia
I just received my WM Intruder Last Week,from my local hobby store...
I'm fly pattern plane such as GILES w/OS!40rx,Venus w/OS FS120SIII,and now iwant to fly WM INTRUDER
Its looks like nice flying this bird...

In my country there is no restriction of engine,so i need your opinion if you wouldn't mind?,
1.Do you think if i put OS 91fx will be good for this bird?,cos I think 91fx have same weight with 61fx(both 19.4oz or 550g) but has a bigger power
2.i plan to set 13x11 APC prop for that engine(OS91fx),is it good or bad?

thank for your time Mr Randy,n im waiting for your replay..

wlcornelius

Hope you don't mind me jumping in on this. I have the Intruder as do about 30 others in the SPA an the weapon of chose is the O.S. 91 surpass 4 stroke or the 91 Magnum. Hope this will help you.

Free Bird

I'm using a Saito .91, 20% nitro and an APC 13x10 prop. This combination works well for me.

FB

okypolice

thank you for the replay wlcornelius,n free bird....the reason im choose 90fx cos i will practice P09 scheduled with this bird,as we know P09 need big power to finished the manuevers,so i dont think o.s 90 surpass can take this bird to finished P09 scheduled with easy...does O.S 91 surpass can take intruder for unlimited climbing?..
my country had a tropical climate,so all of the engine performance will down about 10-20%...

rrcullman

My Feedback: (1)

hey Oky,the .91 4c has unlimited vertical on the Intruder with 30% nitro (coolpower 30% heli is what most of us S.P.A. guys use) but high nitro might be a problem in your location, if you are forced to use lower nitro I would go with .91 2c . As for which prop on the 2c I'm not sure , there's enough ground clearence for a 13.5 inch though.Hope this helps..................Randy SPA 232

okypolice

hi randy....sorry bout late replay, i just came back from duty in the middle of forest...thank you for your advice,i usually use cool power 15%,tomorrow i will be maiden flight my trudy...hope its fly as good as its look..n i put 14x9 apc for the engine.....Oky INA 0533.

okypolice

finally maiden flight was success...my bird flies very nice,readjusment for incidence for 2nd flight and result was good...no trim for ail,rudd,and 2 click down for elev..roll was linear,inverted very little down elev,climbing performance is unlimited...i can finish P-07 sequence with easy..thank you to all who always give me advice and solution...
Best Regards....OKY INA 0533....

okypolice

finally maiden flight was success...my bird flies very nice,readjusment for incidence for 2nd flight and result was good...no trim for ail,rudd,and 2 click down for elev..roll was linear,inverted very little down elev,climbing performance is unlimited...i can finish P-07 sequence with easy..thank you to all who always give me advice and solution...
Best Regards....OKY INA 0533....

crankpin

My Feedback: (15)

Good going OKY, glad you did good.

Crank

okypolice

thank you crankpin,this mornig i started to fly P-09 sequences...

turboomni

Do you guys use the stock tank that comes with the Intruder> ? iT IS A 320CC TANK. wITH A 91 FS motor how long a run time will you get?
Are there any larger tanks you could recommend that will fit rather easly in this bird in the 14 to 16 fluid oz range??
Thanks

turboomni

Another question ,,it seems most mount the 91's sideways ,,do you have to add ALOT of weight to the wing tip to balance it out correctly??
Or is there no problem running it inverted?
Thanks again

crankpin

My Feedback: (15)

I modified the floor to shoehorn a Sullivan R-12 in. Very tight with the foam top and bottom.

Crank

Kruzer

Great thread...!! .75AX.... not an option?

wlcornelius

Stock tank on the Intruder because of the tanks shape,you should get 2 rounds in any class from the SPA. I do.

wlcornelius

Sideways is the way to go, plus a lot less chance of putting the finger in the prop.

turboomni

Thanks i will use the stock tank and mount it sideways.

Wingwrecker

Mine arrives wednesday. This will be my first true pattern plane and I'm pretty excited to see how it flies. I'll be running the Magnum .91 2 stroke and will not be competing.

I've read through the larger threads here on RCU but I'm sure I'll still have questions for you all during the build.

Has anyone found any vids of this plane in flight? I've searched youtube and Google but come up empty-handed.

crankpin

My Feedback: (15)

My World Intruder # 1 in flight.

Crank

Wingwrecker

Thanks for the reference pics. But if a picture says a thousand words then a video says a thousand million!

It surprises me that I cant find one vid of this plane in action.

NM2K

My Feedback: (14)

The 12 oz. size tank was the standard 10cc engine sized fuel tank when this model was designed. This was before schneurle porting and tuned pipes.

Don't forget that you need to use at least a 1/4" of loose foam rubber around the fuel tank to prevent fuel foaming. Having a lot of fuel isn't of much use if your mixture is all over the place because of vibration forming those little air bubbles.


Ed Cregger

NM2K

My Feedback: (14)

Beautiful work, Crankpin.


Ed Cregger

Wingwrecker

So in a frantic search for what I thought were missing set screws for the tail incidence, I finally realized that they were already in place in the H. stab. But I can only feel three of them in there and no matter how much I feel around with the wrench I can't find the fourth.

A moot point either way as I've never dealt with incidence and really have no idea how to set it.

Can anyone explain it to me or point me to a good source?

THanks,
Evvy

turboomni

The 12 oz. size tank was the standard 10cc engine sized fuel tank when this model was designed. This was before schneurle porting and tuned pipes.

Don't forget that you need to use at least a 1/4" of loose foam rubber around the fuel tank to prevent fuel foaming. Having a lot of fuel isn't of much use if your mixture is all over the place because of vibration forming those little air bubbles.


Ed Cregger




Thanks for the reply. I do wonder how you get 1/4 inch of foam around the tank when the opening for the front of the tank and rear are a close fit and all but hard mounted in the airframe . What do you suggest???

NM2K

My Feedback: (14)

In very tight fuel tank installations, such as the one you are mentioning, I've used single sticky sided foam tape, the kind used on wing saddles, placed on the rear of the firewall, the fuselage sides and on a bottom brace that is used for holding the tank in place. It has worked well and it replaces the 1/4" of soft foam rubber in a pinch.

I've designed, built and flown my own model airplanes over the years. It's lotsa fun, but, you will then discover just how much forethought is required when designing models for little things like being able to remove an installed fuel tank to replace the tubing after it has aged and failed. I found myself referring to what those preceding me have done in order to get servicable fuel tank installations while also being installations that are least likely to foam the fuel when the engine is running. There is a lot to keep in mind.


Ed Cregger