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E-Challenged
09-23-2007, 03:33 AM
I designed my Peashooter as an entry in the first design and build-off contest on E-Zone's Scale Electric Plane Forum. The contest was my idea but Charlie Bice of Manzano's Laser Works ran the contest. The contest had categories for pro's ( people who have had their designs published or kitted) and amatuers like myself who haven't. The contest had categories for electric powered military and non-military propeller driven sucessful man-carrying aircraft. Models were "fun scale" with emphasis on flyability. I didn't finish and maiden my model by the deadline but got most votes and an honorable mention in the non-flying category. I have since maidened the model and installed three larger outrunner motors. The model is now flying like the real thing with a Scorpion 3008/32 motor and X-Caliber 2200 3S 20C battery pack and GWS direct drive 11x7 prop. The model weighs 2.5 pounds and needs over 100 watts per pound to overcome the drag and prop blanking of the 6" diameter dummy Wasp radial plus fake wing rigging.

Bill G
09-23-2007, 07:14 AM
I still need to try mine. I was even working on the battery compartment the other day, and got the batt to slide in directly behind the firewall. The more forward, the better. Got some rubber foam in there, to hold the batt in place. Just eerie about flying it, for sentimental reasons.

pd1
09-23-2007, 11:29 AM
Glad you got the power issues sorted out.

Paul

E-Challenged
09-23-2007, 05:53 PM
Bilgie,

I had similar trepidation about maiden flight of mine. Just make sure it is a little nose heavy, if anything, that down and right thrust are adequate, and that thrust feels like a more than enough. Be ready to adjust trim or have a buddy adjust it, while you keep it level when you get some altitude. Mine flew stably with smaller motors despite prop blanking and overall drag but got much better with big enough, low KV, Scorpion motor, 11x7 prop and 20C 3S pack. Prop must be nearly twice diameter of cowl ring/dummy engine and produce plenty of thrust. Over 100 watts per pound is enough for good performance with this kind of design. Mine flies scale-like fast, climbs well and will make large diameter loops and lazy rolls. After about three minutes of near full throttle, power sags and I cruise around at near full throttle then land for a couple more minutes. I haven't tried less pitch or smaller diameter props yet with this motor. Too tight/too small a loop causes a stall and it falls out of the loop like a "shot duck". Rolls need "down" elevator when inverted. I land like a fighter plane with some power onto the mains and give up elevator during rollout to keep tail down. If yours tends to tip over on landing, despite good technique, it may be grossly nose heavy so move battery back or add a little stick-on weight to stab. These stick models are repairable, you have the skill. Best of luck and let us know how it goes,

Bill G
09-23-2007, 06:33 PM
The down and right thrust are difficult parameters. I've got a few planes flying perfectly, that would roll off on launch horribly without the correct right angle. The difficulty is that some planes are more sensitive to this than others, needing different degrees also. Go a bit past, and have fun trying to make left turns.:D

I have learned that your better off flying heavy, than tail heavy, but at this point I hate to add any more nose weight to the plane. I have tons in there as it is.:eek: Still, you have to set the CG properly.
I learned many times over that a tank with the proper CG flies better than a light plane that is tail heavy. It still is difficult to keep slapping all that lead in there though.

As of late, I've flown some planes that completely VOID:eek: some of the "that's too heavy" nonsense that we always hear, so I'm less bothered by adding noseweight.

Flew my 20+ oz Arado 234 last week, with a FlyZone Cessna wing and mere EDF50 fans for power. Flew fine, and not heavy. 80% of the folks on forums would just guess and tell you it will never fly. Same goes for last weeks modified Tom Stryker 109 build. Basically a GWS 109 in size, with the GWS airfoil copied, which was one of my mods. Flew fine (although a bit fast:eek:) at around 22oz. Now we all know what you'd hear on the forums about a 22oz GWS 109. Same thing, they'd all say it will never fly. I could list a bunch more too, that defy conventional wing loading figures, like the 6.5oz 20" Guillows Cessna 150. Flies as easily as any trainer out there.

As for stick models being repairable, build 'em the way I do,:eek: and you'd be surprised what they'll put up with. The Midwest CF spar and rod is expensive, but worth the loot. My Peashooter has real wire wing bracing too, which really helps with wing strength.

E-Challenged
09-23-2007, 07:32 PM
My Peashooter fish tails a little during early part of ROG but stabilizes as airblast from prop increases and bears on the vertical stabilizer/rudder.
I get it rollling then rapidly increase thrust to keep it headed straight.
I think that short-nosed planes are probably less sensitive to amount of right thrust. My Stinson Reliant flew lousy after a crash repair job because downthrust angle had changed to a little up thrust when the firewall was reglued and weight of repairs to fuselage behind wing had changed the cg.
I'm going to lengthen the Stinson's tailwheel leg to lower the nose and help reduce it's tendency to ground loop during early part of takeoff runs.

Bill G
09-26-2007, 03:11 AM
You know 1 plane I've always wanted is the massive CMP Peashooter. Beautiful model, that is supposed to be quite a performing warbird too. If I were to buy a large ARF, that would probably be it.

E-Challenged
09-26-2007, 09:33 PM
I hope Pat Tritle or somebody makes a realistic looking "designed for electric power" kit for a Peashooter in about the same size as mine ( 40" wingspan) but considerably lighter using laser cutting and egg crate wing construction. I have been badgering Tritle to design a Stinson Reliant SR-7 using his built in lightness techniques. His designs fly slow and realistically and land at a fast walking speed using light weight and inexpensive power systems.

Dan Cahill
12-04-2007, 08:15 AM
Peashooters are so cool. A new full scale replica is flying (P-26"Tribute")on
you tube. Some guy wanted to make a Lockheed 10 Electra, and me being new to this place don't know how to tell him there's a Cleveland Model plan.
How do I pass this on? Meanwhile, yes a Tritle P-26 is a kit or plan I'd buy.

E-Challenged
12-15-2007, 03:27 AM
Cleveland still offers plans for the Peahooter in various scales, intricate structure, for experienced builders. I just ordered Cleveland plans for a Stinson Model A Trimotor and a Republic Seabee amphibian.

Just got the Cleveland plans, plan sheets are huge, about 8'x5' , show rubber power, with notes on engine power mods, retracts, and scale details from Mr Packard.

Bill G
05-05-2008, 04:57 AM
Well EC I bet you thought I'd never get around to it.:D
My Sterling Peashooter left off a year back showing major potential, but without alierons, it was too difficult to keep level, and I didn't care to destory it trying, as this was a rubber powered plane that dad built when I was around 12 years old. I got several 100 ft flights in the tall weeds, and saw that it would be fine with ailerons. The plane has little dihedral and definitely needs them.

Putting ailerons in planes after the fact is something I've done enough times, that it's really not that bad. This one went beautifully. I cut the Coverite covering so carefully that I was able to simply glue it back in place, after installing the hingeline header in the wing, and framing in the ailerons. I discovered something new with torque rods also. I always thought they had to be directly inline with the hingeline. They will also work, however, if they mirror the offset angle of the ailerons. When the torque rod rotates, the bent end that inserts into the aileron will rotate 90 degrees to the hingline and will not bind, just like if the rods were inline with the hingeline. The ailerons move freely with plenty of throw. The pics will be worth a thousand words in this case.

The fun part is eyeballing up your tragectory and pushing the torque rods through the wing formers, since the wing is already covered.:eek: If your a hair off, it's hard to take another stab at it, as the rod seems to keep finding the same hole/s that you made. Far off, and you just try again. If you cut your rods with hand cutters, they have a sharp, flat point that drills nicely through the balsa wing formers. You also have the bend that you made which will go into the aileron later, to hold onto while doing this. The other fun part is bending the arms inside the plane after they are inserted, to attach you pivot links to. Gotta get those tweezers/pliers in that little space and be careful, as you can crunch quite a bit if you slip.:D

Just have the servo mounting plate left to go now.
Don't tell me they're not scale eithter, as I cut these ailerons where the wing formers made it most convienient.:D

Bill

E-Challenged
05-05-2008, 05:01 PM
I'm proud of you, glad to see some progress, I'm sure the little 'shooter will fly nicely. Mine still falls out of loops and rolls most of the time so I just fly around in race tracks and figure 8's with dives and climbs using aileron and rudder mix. The big dummy engine seems to make for an unusual amount of drag. Check the cg, slightly nose heavy is ok for maiden/trim flights but too nose heavy prevents good loops and rolls.

If you do attempt rolls, get some altitude, switch off aileron/rudder mix if used, enter roll level or slightly nose down and give a little down elevator while inverted. Rolls to the left may be easier than to the right due to torque. For loops, dive to gain speed and make loops large enough to avoid stalling but not so large as to lose momentum. If your model falls out of rolls or loops, with enough altitude you can recover nicely, too low and splat.

Now about that Seabee, the peanut gallery want's to see it completed and at least high speed taxi tested. Don't attempt flight if it is underpowered or tail heavy.

Bill G
05-10-2008, 01:18 AM
Well it happened at last.:D The Peashooter flies.

This is actually a major event in my rc career, since it was the first plane I ever converted some years back when I started at this. It didn't have a chance back then, and neither did I.:eek:

Dad build the plane originally with rubber band when I was around 12.
As my first completely knowlegeless conversion, I decided to use rud/elev, as I didn't fly ailerons. It would have never flown without ailerons, especially with no dihedral. Then came the gradual reworks. I cut the reinforcing spar that I put through the wing airfoil formers in the center, and added what dihedral I could. Flies pretty well now with about 1/2" dihedral per side, but could use more. Then, I tore off the heavy covering job I did, and went with Microlite. Did this on the elevator too.

Next, I realized it would not stay level with just rudder and little dihedral. A year later, being now, I added the ailerons after the fact (I've gotten good with this mod:D ) and flew it. So, you could say this one's been a long time coming.

As EC stated about forward CG, the CG needed moved forward to 25% of center chord, requiring massive lead in the nose. Behind that setting, it got squirrely, and I knew better than to let it go up when testing. All in all a pretty good flyer, which will really bank on the turns with little dihedral. Not a problem, but not a trainer either.:eek:
I had none of the balloning problem some speak of. I'm convinced that possibly the washout I added, which effectively reduces the incidence of the outer portion of wing panels, must have helped. The planes appears to have a pretty high incidence angle, but was not an excessive climber, and flew with the elevator flap level.

With all the weight added to the cowl (16.3oz AUW), the plane was not a floater and does not slow to a crawl. I kept a decent glide angle on landing, only flaring at the end. The "flare" was basically a fallout:D but at only 1 foot high with tall grass below. I knew better than to slow down too much and stall, until the last moment.

I've seen these on Ebay for around $30-35. I thinking of buying another, and building it with all the afterthoughts on my current one included in the build.

E-Challenged
05-12-2008, 05:24 AM
Congrats on getting 'er flying. Try to find a paved or otherwise smooth takeoff and landing venue. Sounds like it flies a lot like my P-26. I still haven't completely cured it's misbehavior during loops and rolls.

Bill G
05-12-2008, 05:23 PM
Congrats on getting 'er flying. Try to find a paved or otherwise smooth takeoff and landing venue. Sounds like it flies a lot like my P-26. I still haven't completely cured it's misbehavior during loops and rolls.

During the first flight, I didn't want to try any loops and rolls.:eek:
The turns banked really hard, and I didn't want to find out how it behaved when going inverted, without getting a very good feel for the plane. I have a feeling there might be a heavy snap with this plane, if horsed around. Really handles though.

I did add a steerable tailwheel (teeny, to limit tailweight) not too long ago. On nice pavement, it should give some ground handling. Should ROG fine.

Bill G
05-19-2008, 04:55 AM
Had this light half shell Dare navy pilot that I thought would make a good Peashooter pilot. Basically like a Guillows pilot. While they may seem like a pain to build, after so many of them you can really get the speed down, and have a good, light pilot, with the seams sanded smooth. The best trick I've found is to glue the head area together first, and then drop CA into the inner seam line from the inside of the pilot body and activate for fast curing, which give you seam sanding latitude. Next glue the body seams together, pry the bottom open a small amount, and add CA to flow on the inside of the body seams to build up the inner seam area, again to add material for sanding latitude.

Bill G
11-22-2008, 05:30 AM
Well EChallenged, I must be out of my mind.:D Just started on an 17.5" micro Dumas Peashooter, as a thought for an electric conversion. Supposedly a guy had got one flying on RCG, although I never saw any flight pics. For whatever reason, the cute little box picture had been getting my attention forever, and I finally caved in and got it.

Dan Cahill
11-22-2008, 07:57 PM
Say Bill, that's one great looking Peashooter! Winter is here early and I'm toying with decisions to buy/build/complete(!) Was there a Berkeley kit? Do you recommend this Sterling kit instead? Seems like there was a big Royal kit but I don't know whether that was just too heavy to electrify. Was this a printwood or a die-cut kit? One sixth scale would probably be the best size for my skills/house/car, but that would be years of work the way I get interrupted (there's no kit I know of, etc.) Once again, Kudos on a fine job!--Dan

Bill G
11-23-2008, 05:10 AM
Say Bill, that's one great looking Peashooter! Winter is here early and I'm toying with decisions to buy/build/complete(!) Was there a Berkeley kit? Do you recommend this Sterling kit instead? Seems like there was a big Royal kit but I don't know whether that was just too heavy to electrify. Was this a printwood or a die-cut kit? One sixth scale would probably be the best size for my skills/house/car, but that would be years of work the way I get interrupted (there's no kit I know of, etc.) Once again, Kudos on a fine job!--Dan
The Sterling kit is a lot bigger than this one. The Dare Peashooter is similar to the Sterling kit, but the cowl and engine are not as nice, and I believe the wheel pants are not as nice either. I'd like to get my hands on antother Sterling Peashooter. Mine is heavy, but does fly well, and doesn't seem to have the problems I've heard from others who have converted the Dare, or even the Sterling for that matter.
This Dumas kit is a laser cut, while the Sterling is a die-cut. Not sure if the Dare is laser cut, but likely is.

Continuing the 17.5" Dumas build
For a lousy 29 bucks, it would be nice if the kit had a molded cowl, dummy radial, and wheel pants. I guess I'm knocking them, especially since they provided a nice plastic packaged bag with the tanII rubber, prop, prop hardwheel, and 1 wheel. Now what the hell am I supposed to do with 1 wheel? :D I did happen to have 2 more of the exact wheel, as they were from a Guillows kit, where they actually give you 2 wheels. I'm using these thin plastic wheels, to minimize the opening required in the wheel pants, and for the light weight.

On the subject of wheel pants, the kit keeps it simple and has a profile strut, and a profile wheel pant. That's right, just 1 pant that sits on the outside of each wheel. Looks terrible. :D This does not do the beatifully shaped landing gear justice, so I ended up fabbing these parts. The gear struts when made in scale form are quite strong and light, ending up at a total of 4.5 gms for both gear structures and wheels. The axles will simply be cutoff pins pushed through the wheel pants and wheel center, and CA glued in place.

The motor for the project is an Eflite 180. The seem about the same as the 8.5gm outrunners that BP and HobbyCity sell, but maybe a bit higher grade in workmanship, and you pay for it too. These little buggers are powerful though. I had my 24" Storch out today with one of these little 8.5gm outrunners. Installed a new prop and removed some vibrations a week ago and was anxious to try it out. During the previousl flight, vibrations limited the throttle and caused a lucky no damage crash in tall weeds, as it was flown in far too strong of wind that day. It sounded as if it was going to vibrate apart if I applied more throttle, and stalled dead in a strong headwind, thus going into a taispin. The plane flys well, but don't flat out stall these micros and get in a spin. Even the good flying micros are susceptible to this.

Anyways, it was nice and calm this afternoon for the last 1/2mile of my walk with the dog today, got back to car with 10 min daylight left, and suddenly the wind picks up to all hell. I've been waiting a week to fly this thing again and darn it, it's going up. With the vibration problem cured and a better prop, I had no stalling issues as it was flying faster than a lot of my park warbirds do. Not a relaxing flight in 15mph winds, but no issues with power with these little motors. The downwind passes were very entertaining. Faster than some of the GWS warbirds I've had. 30W (although safe only in short bursts) in a 3.5oz plane is 240W/lb!

Bill G
11-24-2008, 02:29 AM
Where ya at EC? Hanging out at that other place too much? :Q

Since the Peashooter was the first US all metal covered monoplane, I had to insert plank the most critical areas of the top fuse, to eliminate the stick-and-tissue look. Would have liked to do the whole thing, but I've done that before and they didn't fly. :D

This project seemed like the best candidate yet to use the Toki bio-wire servos, so I've pretty much decided on them. Testing them again, they are reasonably fast, center well, have good resolution, and plenty of torque for a plane this size. Since they are not as strong as BA 2.5 servos, the plane will have pull-pull string linkage. Still debating ailerons, but to avoid complexity, the plane will probably be rud/elev, with the largest drawback being added dihedral for rudder control. I had thought about using the Tokis individually with pull-pull linkage for the ailerons, and then a BA 2.5 for the elev.

One thing I'm not worried about is power. You definitely get what you pay for. I wasn't thrilled with the $37 cost of the Park 180, but it is certainly more powerful than the comparable ELE outrunners that BP and HC sell for less. In fact, with a 4.5" prop on 3s, I'm convinced the motor could keep a GWS park warbird in the air. :eek:

The Peashooter is not a particularly light plane for rc. The heavy cowl is needed to balance the short nose, and you would just have to use lead anyways without it. The landing gear is adding 4.5 gms, and omitting gear would look terrible on a Peashooter. I'd like to end up lighter than the 3.5 oz that my 24" Storch came out at. While trying for less, I'm being realistic about the expected weight. From previous past experiments with heavier gear, these 17" planes will fly at 4oz, but not well. Some weight that can be reduced would be batt weight. The 300mah 2s and 3s batts I have are more than necessary for the plane, and a 200mah would be fine, dropping around 6 gms. I probably will order a 2s-200, or maybe even 150 with a good C rating.

Edit: All framed up now. Post pics later.
With the entire barebones structure and all gear including batt, the AUW is now 68 gms. (including 2 gms added for wing pan formers/stringers not yet added)Better than I was expecting. With the very light Dumas wood, the CG is right at the rear edge of the wing LE spar. This is excellent, as it allows me to mount the .8gm Toki servos above the rear of the wing, accessible from the cocpit, and finish the plane with Microlite covering, without needing nose lead.

E-Challenged
12-05-2008, 06:40 PM
Maybe I mentioned this before but we are finished with wife's chemo and radiation treatments for breast cancer and nearly finished with our concurrent home refurbish/remodel project. My models and stuff are still out in the storage pod, gotta clear some space in the garage for a new modelling area and my motorcycles, etc., etc. Your little shooter looks good, hope it flies well after the obligatory tweaking. Funny how a given real plane grabs your modelling fancy, mine has always been the Stinson SR7-8 Reliant.

E-Challenged
01-04-2009, 12:10 AM
A guy in Switzerland is building a nice foam rendition of a Peashooter, the build thread is here :

http://www.rcgroups.com/forums/showthread.php?t=975343

Bill G
01-04-2009, 01:24 AM
Hope all is well over there.

I see you finally saw my mini. Got a pretty good flight on it, after adding additional right-thrust. Should even be better after adding a bit more right washout, to counter left torqe roll. With the lack of calm flying days here, it may be a while before it flys again.

I found that foam thread just yesterday. Looks like a good effort.

E-Challenged
01-28-2011, 05:24 PM
I changed the motor thrust and took off, lost orientation while fumbling for the trim buttons, crashed in the deep thicket, was lucky to find it. Damage was extensive. Opportunity to refubish 3 year old model and make some improvements. Cowl ring and dummy engine were way too big. Got new 4 1/2" diameter Wasp radial from Park Flyer Plastics ( Sparks) and made a new laminated balsa sheet cowl ring to fit. Installed larger/higher wattage Scorpion outrunner, relocated 2200mah lipo under the wing, making larger fuselage fairing with open ends for battery cooling. Gotta recover parts of fuselage and wing and paint 3 color design on ring cowl. Hopefully, model will have enough oomph to do loops and rolls but flight times will be a little shorter. Shoulda built larger for more lighter wing loading.

Bill G
02-04-2011, 12:27 AM
E you're scaring me. :eek: I need the motivation to fly my Peashooter, after installing a more powerful motor. It should do fine, as it flew well before, but it is a converted rubber build of Dad's from the mid 1970's.

Seriously, it's good to see you back on it. I saw the rebuild pictures that you posted. I've done countless rebuilds on my Dumas Peashooter, and they weren't even due to crashes. :Q It was about my first conversion, and I lost the desire to fly it, as I had no skill, and kept discovering more things that I had not done well. It now has the tail surfaces covered with Microlite to reduce noseweight (can't do enough of that) and also has the wing recovered with Microlite. I'm not sure how much I have left of it, but I don't use yellow Microlite often. If I have a reasonable amount left, I should send you it and talk you into recovering the wings and tail with Microlite. A bit of semi-transparent sacrifice, but the weight reduction is worth it.

BTW, I see your wing is braced like mine. Of all things, you ain't breaking the wing on this plane.
Also, I just saw the new Alfa Peashooter. I don't know if Hobby Lobby will carry them, and they will likely be more expensive than others, if so. Still, it may be the first "gotta have" ARF in a while. Sadly, I'm as broke as they come.
http://static.rcgroups.net/forums/attachments/4/0/3/1/a3752783-126-p26_IMG_7384.jpg?d=1295879009

E-Challenged
02-13-2011, 08:33 PM
Hi Bill, beautiful job on the Sterling version. Make sure that it is somewhat nose heavy and that you have down and right thrust for the maiden flight. Maybe a little down elevator and right aileron would help control torque, etc. I got busy and repaired my Shooter, added stick on weights to the motor stand offs, and more down thrust. The next attempt has to go better. Maybe Park Zone will come out with an easy to fly BNF foam Peashooter as I suggested. Their Stinson SR-10 is a beautiful flyihg foamie and has been a surprisingly big seller.

E-Challenged
02-16-2011, 02:49 PM
Things didn't go better, tried to take off, stalled and crashed. Damaged on landing gear legging and wing, but not too badly. Will be moving batter pack back to original position behind the firewall in a vertical position. There must be a change in cg due to a pendulum affect when model rotates on take off with battery under the wing fore and aft position. In old battery pack position it didn't go nose up and stall. Model was balanced nose heavy and I did try to keep climb angle shallow.

decender
04-09-2011, 02:32 PM
hey all u P-26 builders. I have a Royal kit all done up waiting for a power plant. The airframes comes in at 8.25 pounds. Not bad for a fully sheeted plane. Anyway, the bad news is that it needs 10 pounds of nose weight to balance. Did anyone have the same experience?

That sure puts alot of stress on the landing gear and airframe. Not to mention the 50 plus oz. wing loading.

Think it will do it? The funny flat bottom airfoil may be able to handle it.

Any good news for me.

Thx, Steve

E-Challenged
04-09-2011, 09:14 PM
Not sure what your wing loading will be. If this will be electric powered, consider mounting battery pack protruding through the firewall next to the outrunner. My E-powered Peashooter has the 2200mah 3S 25C pack in a vertical compartment just behind the firewall and is actually a little nose heavy. Don't understand why yours is so radically tail-heavy. Are you sure of the correct cg balance point?

decender
04-09-2011, 09:56 PM
not sure why either. few guys have seen it and they say weird that it is this tail heavy also. using 25% for cg starting point.

E-Challenged
05-17-2011, 07:24 PM
I attempted aviation again with the Peashooter last week with lipo mounted back behind the firewall. I told the others that I intended to fast taxi it to check it's tracking etc. Naturally, when it got up on the step I let it lift off and climbed steadily so I did a couple larger circles of the field and decided to land because of gusty condtions. While landing, nose down, 1/2 throttle it simply stopped flying and fell out of the air from about 10 feet altitude. Damage was fixable. I have decided it's just too heavy at nearly 20 ounces per square foot wing loading. I have finally decided after some 20 nice take-offs and maybe 10 nice landings, to retire the model and hang it up while it still looks presentable and use the innards for a future project. There are good reasons why there aren't any really scale-like Peashooter kits intended for electric RC. The large dummy engine, ring cowl, landing gear covers and rigging wires make for excessive drag, requring a heavy motor and 2200 3S lipo, vs the small wing area with stall prone elliptical wings.