rowdyjoe

My Feedback: (9)

Thanks for the good wishes and the video Jon. Iappeciate it. I think I"ve seen your vid before on YouTube. Thanks for not goofing it up with a bunch of music. The sound of that great running 4 stroke is music enough for me.
My first Intruder is still out in the "hangar" less engine, servos, etc. I bashed the vertical off of it with a ceiling fan and decided to start with a new airframe rather than rebuild. It really needs a complete overhaul. Although it's structurally sound, it needs a cosmetic make-over. I flew the old one with an OS.61 two stroke and it was a great flyer. That's why Ichose it again ...and the price isn't bad either. Airborne Models even shipped it for free as a promotional deal.
The Saito .91 Ihave mounted on it should provide great power. Ijust need to find the right prop. There are a few folks in our club who have owned and flown the Intruder and they didn't like the way it flew with a 4 stroke. Ifigured they didn't have it propped right so, I'll be doing the prop testing thing until Ifind the right one. Ilike wood props and have a 13x8 on it now. It seems to pull fine on the ground but, the tale will be told in the air. It's difficult to decide which prop is best by using the experience of others due to the variety of engines used but, I'll get it figured out soon Ihope. It's too close to the ground to take anything longer than a 13" prop unless Iinstall bigger wheels. I'm not sure I like the stock tires anyway so Imay go with a set of 2.5" wheels and experiement with 14" props.
Take care and enjoy your Intruder. I agree, it's a great flying bird.

RJ

Dave Harmon

Hey Joe.....
I used an APC 14x8 on an OS 91 pumper running CP 30% Heli fuel.
It ran really great and the fuel gives the increased torque for considerably better performance.
If the Intruder was about a pound lighter and had more rudder it would be a lot better but if you keep the speed up it isn't too bad.
Pretty good dollar value though once I got the pushrods squared away.
I used 2 1/4" light wheels to try to hold down the weight.
The Saito should be ok but try that Heli fuel....makes a big difference.

rowdyjoe

My Feedback: (9)

Thanks for the tip Dave. I have tired heli fuel in my other two Saitos (bot FA-80's) and it does seem to help. However, Ihave a Turbo-Header on one and it gives me about 300 rpm more running 20% or 30% so, I've stayed with 20% for those two engines. Idon't have that muffler for the .91 so heli fuel may do the trick. I'll fy it on the 20% (because Ihave it on hand)and see how she performs. If she needs it, I'll pick up a Turbo-Header for it ANDrun 30%.

RJ

Dave Harmon

With the APC 14x8 the engine needs more torque to pull the larger more efficient prop.....not more RPM. The 20% fuel is not enough for that prop.
The 30% fuel will probably do the job....instead of losing RPM on an upline this fuel will maintain the RPM and the flight performance will increase substantially.
Try this combo first and see how you like it and then the header if you think it is needed.
Better adjust the valves while you are at it and use an OS F plug.

rowdyjoe

My Feedback: (9)

Judging by the performance I'm getting with 14x6 on my FA-80 with Turbo-Header, the 20% may be enough. Idon't like to run plastic props if I can avoid it. I prefer wood. Ihave a wooden 13x8 on it now and may not be able to fit a 14" inch due to ground clearance ...unless Iadd larger tires (which equal more weight).
Iappreciate your advice and will give it serious consideration if I decide to go with a plastic prop.
I'm told that the OS .91 develops a bit more HPthan the Saito so, 30% heli may help make up the difference. I'll give it a try. Ido know that 30% helps cool the engine better during our hot summer months when we have temps in the high 90's and lower 100's. One of our club members advised me to use it during that period and, along with some cowl baffeling, helped to keep the FA-80 cooler.

RJ

rowdyjoe

My Feedback: (9)

Here she is, all dressed up and ready to fly. Ibalanced her this evening and changed out the rudder/steer servo for one with a lot more torque and a bit faster in reaction time ...and it centers better.
Hope to fly her soon and tomorrow afternoon is looking good.
That's a Top Flite 13x8 prop but, I usually run a Xoar or Zinger Pro. Ineed to stop by the LHS and get some spare props.

RJ

Dave Harmon

Alright JOE!
It looks pretty good!
That is the exact same setup I had...you will have plenty of clearance for a 14" prop.
Balance it so that it teeters on the main wheels ready to fly without fuel.
When you add fuel the c/g will move forward a bit and keep the nose wheel on the ground....they fly best when balanced this way.
Oh...you might need a foam clunk for the tank. This is a YS part and available from Central Hobby.
I was having trouble with the fuel slinging away from the clunk so I changed to the foam clunk that kills air bubbles.

rowdyjoe

My Feedback: (9)

Thanks Dave. I didn't spend a lot of time dressing her up but, the pinstripes help her stand out from the crowd a bit. Being an Air Force guy, I'm not real enthused about the Navy markings so, I'll leave it mostly plain unless I see something that catches my eye. I'll bet she'll fly just a well without those decals as with.

She's balanced just a smidge in front of the position you describe. I wanted to make sure she was bit nose heavey for the first flight. Ilike my aerobatic planes to balance as near to neutral as I can get them. How much forward stick it takes in inverted flight will determine how much and which direction I need to add weight ...if any. i hate to add dead weight but, if ya' gotta, ya' gotta. Which reminds me, Ihaven't balanced her laterally yet and she seems to favor the side with the muffler. I may need to add a bit of lead to a wing tip to counter that.
Hey, good tip on the foam clunk. Hadn't heard that one before but, I'll sure give it a try. I've been a little concerned about fuel foaming becuase I didn't add any foam around the tank. The YSclunk may solve the problem for me.

I'm excited about the first flight. It's been months since I flew my old Intruder and Idon't remember much about it but, I do recall she's a pretty honest bird and has plenty of speed. I liked my old one a lot and wish Ihadn't knocked the vetical off but, becuase of that I have a brand new bird to help me learn all over again. This is going to be FUN !

Garry

Dave Harmon

Garry.....the Intruder does not have anywhere near enough rudder to do a stall turn unless the c/g is as I described. I think I had a small amount of stick on lead under the stab....but I had the heavy APC 14x8 also.
Even then you have to fly it just right and sometimes add some throttle gently to get it over the top. It lands and flies very nicely at the rearward c/g.
If any airplane is nose heavy it becomes more difficult to do a stall turn because there is less of the nose fwd of the c/g so it takes still more rudder power to get the now longer tail behind the c/g to go over.
If you feel it takes more down elevator to fly inverted that is comfortable....reduce down elevator expo...or depending which radio you have...add opposite expo to make the elevator more sensitive in the DOWN DIRECTION ONLY.
By the way....My Intruder's factory installed pushrods were binding so badly I had to cut into the bottom of the fuse at the rear former to remove all that junk.
I installed Sullivan pushrods that were very free and had no trouble. A local friend had terrible control problems until he fixed it.
His servo arm was flexing so much that it was sure to break off if he had flown it much more.

maukaonyx

RJ, the pinstripes give some added pizzaz to the color scheme...good job! Have fun on the maiden. Jon

rowdyjoe

My Feedback: (9)

Thanks Jon.

rowdyjoe

My Feedback: (9)

OKDave. I'm paranoid about first flights and aft CG. I've lost a couplel of birds that way and want to make sure I don't loose this one. I'll move the CG as needed to set her up the way you describe after I get comfortable with the way she handles. Ineed to get used to the speed again. I've been flying my 50cc bird and, although she move right along, she appears to be flying slow because of the size (88" wing span). The Intruder will appeat to be flying faster due to her size.

Will you be making the trip down here to Ft. Worth for our April SPAcontest? It would be great to shake your hand. (have we met before?)
No need to worry about competition from me as I fly Basic and have last place sewed up.

I need to get off my duff and take this bird to the field today. Ithink we're both ready to fly.

Garry

rowdyjoe

My Feedback: (9)

First flight success !!!!!! Couldn't have asked for better weather today. It was beautiful.
She flew very well with a few clicks of up trim needed and a couple of clicks of right trim. I forgot to balance her laterally so I think that would account for the right trim. She is well balanced and flies with a bit of up elevator but, I think that can be fixed with an incidence adjustment on the horizontal. I tried adjusting it at the field today but, went the wrong direction and ended up with more up trim. (duh) I adjusted it back to neutral at home tonight and will try again next time. The rates Ihad dialed in were a bit hot for competition so, Idialed back the rates and left the expo alone. I'm pretty happy with it right now but, after Iget used to it things may change. She's a hot flying bird but, will slow nicely for landing. I'll have to get used to slowing her down as all of my landings were halfway down the runway with a long taxi back. We have 450 ft. of beautiful concrete with an adjacent grass runway that's still a bit rough in spots.
The engine is pulling very strong with the 13x8 wood prop. Plenty of up and she hammers very well. Didn't even have to go to high rates on the rudder to get 3 nice hammers (stall turns) out of her. I botched one by letting her get out of shape in the up line. Inverted flight is very manageable and with 50% differential she rolls very straight but, will do better when Iget the incidence worked out. Loops are very easy but, I need practice to make them concentric for the judges. I can tell I'm rusty on the sticks but, this bird will be ready come contest time.
I got 4 flights in today. The weather was just about perfect. Very light winds right down the runway and it was just a tad too warm for the heavy shirt I was wearing. I wish I had gotten there sooner but, 2:45PMwas as early as my lazy body would allow today. We had a large crowd at the field today and eveyone was having a ball and enjoying the great weather. Daylight lasted until almost 6PM with clear skies and several of us used every last minute of it. We don't get many days like this here in north central Texas.
I made a couple of small mods to my Intruder this evening. The glow starter is a real pain to hook up to the plug so, Iinstalled a remote glow igniter system and it will work much better. Ialso realigned the horizontal and gave the engine a tweak toward lean as she appeared to be loading up at idle. This old Saito FA-91GKis turning about 9500rpm with the Top Flite 13x8. I was hoping for more rpm but, it seems to be handling the task very well so, Ishouldn't complain. I also found out today that a 13" prop is the longest we're allowed to fly with in SPA competition. That was news to me but, it's OK because my engine is performing well with the 13x8.
I'm a happy pilot and will be looking forward to many fights with this very nice plane.

RJ

cmgtech1

Dave is 100% spot on with his recommendation of how the WM Intruder should balance. I wound up pushing the cg back until the plane really didn't want to have the nose gear on the ground without fuel. I understand your conservative approach to maiden flight, but to really pull that last little bit of joy out of your point rolls, You'll want to take the cg back to at least where Dave recommends. You'll notice less pull to the canopy with the cg a bit further back and she will hang onto the knife edge position a little easier as well (although she really doesn't like flying knife edge for an extended distance). She will hang the points just fine for the brief amount of time you'll need for the point rolls, and she's a joy in the slow roll. The more rearward CG also seems to help the stall turn a bit as Dave mentioned.

For the price, WM has really given the modeler an excellent "old school" model to enjoy. Unless the Intruder is nose heavy, she's a piece of cake to land. A nose heavy intruder will land at about mach 2.2. Having the CG set so that the model barely wants to sit on all 3 wheels (without fuel) is a very comfortable flying airplane, especially in the landing. Start pushing the cg back from there and and you will want to exercise a little caution while setting up the landing to avoid getting too slow too soon, although she never seems to really get that "snap rolly" feeling. Go with Dave's recommended CG and I think you'll be amazed at just what a sweetheart this WM Intruder really is.

rowdyjoe

My Feedback: (9)

Thanks for the advice and recommendations guys. I appreciate it.
Once Iget the incidence worked out on the horizontal, I'll start pushing the CG forward to make the nose lighter. She's balanced at 6.5" back from the leading edge right now with 3/4 oz of lead on the firewall. I tried balancing her at 6 1/4" back but, she was waaaay too tail heay and would have required much too much weight to balance. She needs a bit of forward stick when inverted and the cause of that is probably incidence. In a way I'm glad they included the adjustable incidence but, I sort of wish they hadn't done it. It makes tuning the the CG a PITB.
I need to find someone with incidence meters and set her up correctly. This hit a miss stuff is very confusing.

RJ

rowdyjoe

My Feedback: (9)

Ok guys, I've taken your advice and balanced her where she's barely able to stand on three legs. The slightest nudge sends her tail to the ground.

RJ

crankpin

My Feedback: (15)

Hey Rowdy - Those stripes, good idea, sets it off well.

Crank

rowdyjoe

My Feedback: (9)

Thanks Crank. Ihand painted those myself. Uh, well, uh ...maybe it's not paint but, I did apply the pinstripping myself.

RJ

rowdyjoe

My Feedback: (9)

First flight with the new CG will be tomorrow. WX is supposed to be very good ...warm with winds 5 to 10mph right down the runway. I hope the forecast holds up and the plane handles as well as you guys say.
I've had a couple of birds with the CG too far aft and I'm pretty paranoid about that but, I trust you guys are right.

RJ

rowdyjoe

My Feedback: (9)

Gee, have you guys been waiting on me?

The subsequent flights went very well. I found a good buy on an incidence meter and set the horizontal to the same incidence as the wings and it has had a positive affect.
Iput 3 flights on it today in great conditions ....winds between 5 and 10mph and variable. It swung around from north to east as the day wore on but, the Intruder handled the crosswind in fine style.
She hammers very well and with a bit more differential she will roll very straight. She's good now with about 50% but, I think I'll try bumping it up 10 pts and see how she behaves.
Balance is very good with just a touch of forward stick when inverted. Imay add another 1/4 oz to see how it affects her.
The Saito .91 is running great and I'm very happy with the way she's flying now. I'll continue to tune her as I practice for SPA. The season starts in April for us here in the DFW area. Ihope to be able to make some of the "away" contests this season.

Thanks for our help and encouragement. Sorry it took so long to post an update. I'll try to do it more often.

RJ

rowdyjoe

My Feedback: (9)

Well, between then and now I haven't been able to do much flying. HIgh winds or chores have kept me from the field. The Intruder has been pulling left on uplines and Ihaven't been able to trim it out. So, I adjusted the engine down and right to address the issue. On the next flight it didn't seem to have any affect and was disappointed. However, upon checking my transmitter I noticed that Ihad not centered the rudder trim (duh). The next flight was cut short and Ididn't get to check out the upline issue.

Since then I've decided to completely change radio systems. I wanted something with more channels but, didn't want a DX8 so, Ihave sold all of my Spektrum gear and have purchased a Hitech Aurora 9 and several receivers. The new equipment should be here by the weekend or early next week so, I'll still have a little time to practice my SPA sequence ...providing the wx cooperates ...before the contest at the end of this month.

RJ

Dave Harmon

Sounds good Garry.
One thing you said that attracted my attention....you shouldn't need any aileron differential on that airplane.
You may be flying too slow....remember that the airplane is really too heavy to fly slowly and expect it not to wallow around. A full F3A airplane is just barely a pound heavier with several times the power and aerobatic ability.
Keep the speed up at all times and use the turnaround downlines to gain speed....keep the throttle wide open and the speed up and you'll likely fly it better.
Don't make the uplines on each end so tall that the airplane stalls.....this is where the 30% fuel will show up.
Keep it flying even though it is in an unusual attitude.....it can wallow around at just above stall speed even if the throttle is wide open.
Keep the speed up at all times.
Fly it like a P-47.

Dave

rowdyjoe

My Feedback: (9)

Dave,
I may remove the differential once I get the thrust angle worked out. Rolls looked more like a barrel before the adjustment and I'm hoping the new thrust angle will help improve that.
My new radio equipment should start arriving today(Thurs) or Friday and I should be able to get the Intruder programmed quickly (I hope). The Aurora 9 is a sophisticated transmitter but, appears to be easy to program.

Speed and power has not been much of a problem for the Intruder. The Saito FA91 has mucho compression and pulls it very well through the maneuvers with a 13x7 or 13x8 prop. It has very good vertical performance.

I have a bit of a problem when doing stall turns the way you describe. If the airplane doesn't stop at the top at the turn, the judges take away points. So, I'm learning to hit the rudder switch for high rate to do the stall turn. It's been working for me as long as I remember to hit the switch before Ienter the maneuver. Sometimes Ineed a short burst of power to get her to swing the nose over at the top but, generally not. Having a fairly fast rudder servo helps I think.

RJ

maukaonyx

rowdy, I just caught up on all the posts since January, and have enjoyed reading your progress with the Intruder. Makes me want to take mine out now. I think my OS91SurpassII is getting tired because she does not make the Intruder whistle like she used to. Might need some retuning to get the speed up. I agree with Dave about this plane liking the speed to fly better, and I just checked my programming...no aileron differential on mine either. I'm no expert like Dave....I just am happy my setup sounds like his, lol! Jon

rowdyjoe

My Feedback: (9)

Hi Jon,
Good to hear from you. I know Dave is right but, trying to "see" what he's telling me is difficult until Iget to the field and try it. Iguess I'm a bit thick between the ears. My Intruder is a bigger challenge to tune than some of the other planes Ifly and I think the pressure of the upcoming contest is making it feel that way. I don't know why I'm feeling pressure. I don't fly well enough to be truly competitive. Ifly for the fun and fellowship and Ineed to remind myself of that more often. I'll get it tuned but, it may not be compleletly to my liking by the time the contest rolls around. I definately need more stick time with it. Come on good weather.

Garry