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Author Topic: Flat Wing P-30  (Read 4351 times)
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calgoddard
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« Reply #25 on: June 12, 2020, 08:19:22 PM »

I have attached a picture of a prototype "flat wing" that I quickly built.  The soup can was included in the picture to give the viewer a better idea of the size of the wing. It measures 29 7/8-inches by 4 1/8-inches.  The tip plates have been tack glued on with generic glue similar to that sold under the Duco brand. They will later be easily removed with acetone before covering the wing with Esaki tissue.  When shrunk, that tissue will add a lot of torsional strength. I usually cover wings with the grain of the tissue extending span-wise.

The weight of the flat wing frame as shown is 10.40 grams.  That’s descent considering the heavy balsa wood I used to build it.
  
I purposefully used heavy balsa wood for durability and resistance to warps.  This wing will be a component of a beginner’s P-30 so there is no need to try to build near the 40-gram minimum set forth in the P-30 rules followed in the United States.  I used 9# wood for the 1/8-inch square leading edge (later rounded), and 12# wood for the 1/8-inch square main spar.  The two 1/16-inch square stringers were made of light balsa wood because that is all I had access to during my stay-at-home.  I am running low on 36-inch long sheets of 1/16-inch thick balsa wood. The ribs were cut from a sheet of 1/16-inch sheet balsa wood that had an overall density of 10#. Some of the individual ribs felt like they came from a lighter part of the sheet.

The tip plates measure 4 1/8-inches in length and have a maximum height of 2 5/8-inches.  They might be a bit tall. If test flights show that my beginner's P-30 exhibits good lateral stability, I may progressively cut down the tip plates with scissors at the flying field to see if they can be reduced in height without impairing roll stability and recovery from turbulence.  The tip plates weigh a combined 3.15 grams.  Reducing their height would reduce weight and drag.

The wing ribs have a Neelmeyer airfoil with a flat bottom.  Cutting, sanding and notching fourteen uniform ribs was time consuming.  A novice could easily assemble this wing frame in less than an hour with laser cut ribs. I purposefully did not build in any wash-out as I want to see if adequate lateral stability can be achieved without adding this complication for a novice.
 
For those who have been following this thread, you know my reason for using a flat wing on a beginner’s P-30 model.  To reiterate, novice builders often have difficulties properly inclining and joining built-up angled wing sections.  A flat wing with vertical tip plates is the easiest built-up wing to construct that can provide sufficient lateral (roll) stability.  The tip plates effectively provide the flat wing with dihedral.

As usual, your comments and suggestions are welcome.
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Re: Flat Wing P-30
« Last Edit: June 12, 2020, 08:41:10 PM by calgoddard » Logged
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« Reply #26 on: June 12, 2020, 08:41:02 PM »

Cal, my only exposure to a 'flat wing' model was, decades ago, witnessing flights of a glider with this configuration - as published in a British magazine of the time.

It flew quite well in near calm conditions, was a little unhappy when towed quite fast in little wind; from what I remember of that far-off day  its stability was marginal and glide pattern easily upset.

With no more personal experience than this I would, with the greatest respect, not consider such a wing for a  P30 .. least of all for a beginner's design.  Had a flat wing have an advantage over dihedral/polyhedral then such would have long been seen in numbers on the flying field.  Other than general structural simplicity, stability is essential and I do not see a borderline level of such as fulfilling the requirement of intended  purpose.

Ultimate performance is not a requirement of a model proposed for youngsters, in particular. Easy to build, strong, easy to trim and fly proved ideal for my boys  (when they were boys!)  ... a robust model which briefly out-climbed  Coupes of the time ... no freewheel so a fast descent quickly returned the airplane to the flyer's hands. Novices do not seek ultimate performance ...  a stimulating power pattern,  a fair but fast glide ..and not far to walk to retrieve and return to wind up and fly again ... and again.

A strong ... if overweight ... dihedralled P30 with no freewheel would likely be good for up to a minute; given successful flights an upgrade to a freewheel would add some performance.  Hopefully the builder/flyer would be hooked by then  !

Cal, please appreciate  I'm not trying to wet-blanket your thoughts and proposition.  I hope you'll build and fly your flatwing airplane and would be  very interested in the outcome; I love  P30 and an improvement in layout and performance would always be welcome.

Respectfully,

Jim
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calgoddard
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« Reply #27 on: June 12, 2020, 08:55:06 PM »

Jim -

Thanks for your input. Yes, I too have wondered why there are few outdoor models with tip plates.

My latest free flight endeavor could well be a waste of time.  But I currently have time to waste.

I really liked the Square Eagle as a beginner's P-30 but it is no longer being kitted.  The ONE NITE 28 has been re-named by the successor to Peck-Polymers but is currently out of stock.  Unfortunately that model did not accept a typical P-30 blast tube.

The old HOT BOX design by John Oldenkamp is a very good beginner's P-30 if you have to scratch-build. It uses a "Cracked Rib" design in the wing which eliminates the tedious job of cutting, sanding and notching wing ribs.

Jim - I really want to thank you for all your input on HPA over the years.  Among other things, I think you stressed the need to round the upper surface of the nose block plug on OTR models.  This tip probably saved my carved balsa wood props from breaking on a number of occasions.

« Last Edit: June 12, 2020, 10:13:16 PM by calgoddard » Logged
calgoddard
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« Reply #28 on: June 18, 2020, 06:17:39 PM »

I am attaching a picture of the fuselage frame of my beginner’s P-30 which I just completed building.  It borrows from the design of the Square Eagle P-30 fuselage.  I constructed the fuselage in the picture with two “slab sides” made of 1/16-inch sheet balsa wood.  As shown, the fuselage frame weighs 8.4 grams.  

Fabricating and joining the slab sides from scratch took a lot longer than building a conventional box frame or making a rolled tube for the fuselage.  However, if the parts were laser cut the assembly would take less time to build than the traditional P-30 fuselage designs.
 
The fuselage measures 28-inches long x 1 1/8 -inch wide x 1-inch tall.  It will easily accept a blast tube of sufficient internal diameter to accommodate a standard 6 x 1/8-inch P-30 rubber motor. The laminated nose block and 9 ½-inch plastic prop (not shown in the picture) will extend about 1-inch forward from the front end of the fuselage.  If a Gizmo Geezer prop assembly is used, two inches of length beyond the forward end of the fuselage will ensure that  the airplane does not exceed the 30-inch limit in the P-30 rules.
 
I cut the ¾-inch round holes in the slab sides to save weight using a segment of Aluminum tube filed to sharpen one end.  This tool is similar to a hole punch except that you do not ram it through the balsa wood. Instead, you manually spin it to cut out a circle of balsa wood. Filing one end of a segment of a Brass tube or a Copper tube would probably make a better cutting tool as the edge would stay sharp for a longer period of use.  I didn’t have Brass tube or a Copper tube of this size available.

The motor peg holes are located to achieve a 19-inch hook-to-peg distance. That’s the length of a conventional 6 x 1/8-inch 9.8-gram P-30 rubber motor.  The area on the inside of each slab side surrounding its motor peg hole is reinforced with a small vertical section of 1/16-inch sheet balsa wood and a small square of 1/64-inch plywood. A 1/8-inch hole was drilled in each vertical balsa wood section and plywood square to accommodate a segment of 1/8-inch outside diameter Aluminum tube which will serve as the motor peg.

¼-inch diameter holes were drilled in the tail section of each slab slide to reduce weight. 3-inch long tapered notches, 1/8-inch tall at their forward ends, were cut into the upper edges of the tail section that will provide negative stab incidence of 2.4 degrees.
 
The slab sides were joined with 3/32-inch square balsa wood cross-pieces.  The fuselage sides with all the holes and notches can be laser-cut if my beginner’s P-30 is ever kitted.
 
The 3 ½-inch long nose section is fully sheeted without holes in the sheeting. This is because the modeler will need to handle this portion of the fuselage while inserting the nose block. In the nose region the upper edges of the slab sides and the rectangular top and bottom pieces can have laser cut interlocking notches to facilitate assembly.  A beginner should easily be able to assemble this fuselage frame in less than one hour using laser cut slab sides, laser cut top and bottom nose pieces, along with pre-cut 3/32-inch cross pieces.
 
I will cover the fuselage frame with Esaki tissue with the grain extending perpendicular to the longitudinal axis of the fuselage.  This will add considerable torsional strength once the tissue is shrunk and doped.

Your comments and suggestions are welcome. P-30 is a great event! I am hoping my beginner's P-30 will inspire beginners to become involved in the free flight hobby. Test flights will be needed to validate that the flat wing provides sufficient roll stability.
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calgoddard
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« Reply #29 on: June 22, 2020, 05:17:07 PM »

I built a stab for my beginner’s P-30 as shown in the attached photograph. It mimics that of the Square Eagle P-30 except that I opted for twin 1/16-inch sheet balsa fins attached to the ends of the stab instead of a single vertical fin aligned with the center of the fuselage. Securely mounting a single vertical fin to the rear portion of the fuselage (common P-30 configuration) or the center of a horizontal stab in proper alignment can be difficult for a beginner.  In constructing the tail feathers of my beginner’s P-30, each fin can be readily glued in a vertical position to a corresponding outermost rib. In the attached photograph the twin fins have been tack glued onto the outermost ribs, and will later be removed to facilitate covering the stab with Esaki tissue.

The rear ends of the stab ribs are glued in notches in the trailing edge, to increase strength at these critical joints. These notches can be laser cut if my beginner’s P-30 is ever kitted. The span and chord of the stab (including its twin fins) measure 12 3/4-inches and 3 inches, respectively. The fins measure 3-inches in length x 1 ¾-inches in height x 1/16-inch thick.  Their combined area is more than double that of a typical single P-30 fin and therefore the twin fins should have enough area to provide sufficient yaw stability. The weight of the uncovered tail feathers as shown in the attached photograph is 3.31 grams.
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Re: Flat Wing P-30
« Last Edit: June 22, 2020, 05:30:22 PM by calgoddard » Logged
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« Reply #30 on: June 24, 2020, 12:46:23 PM »

I made a mistake in constructing the stab of my beginner’s P-30.  It was supposed to have a 3/32-inch square main spar and two 1/16-inch square stop spars.  I simultaneously sanded notches in the lower side of a bunch of 1/16-inch sheet ribs for receiving the main spar using my 3/32-inch notch sander.  Then I incorrectly used the same sander to sand notches into the upper side of the bunch of ribs.  I forgot to switch to my 1/16-inch notch sander. When I realized my mistake, I decided it was too much work to make all new ribs.  Rough calculations using John Barker’s 2005 SHEET AND STRIP WEIGHTS IN GRAMS chart indicate that this error resulted in about 0.2 grams of additional weight.  This is still bad because even a small amount of unneeded weight at the end of a long tail moment is undesirable.  However, the upside of my mistake is that the stab will be less prone to warping with larger top spars.
 
If my beginner’s P-30 model is ever kitted, it will probably use a 1/16-inch x 1/8-inch main spar in the stab, with the 1/8-inch dimension oriented vertically.  It will use 1/16-inch square balsa wood sticks for the top spars and 1/16-inch sheet ribs. If the stab used 1/32-inch sheet ribs I fear it would be too delicate and too prone to warping with tissue covering.  Such a light construction would probably be fine with Mylar film covering.
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flydean1
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« Reply #31 on: June 24, 2020, 01:01:59 PM »

Just an observation not necessarily negative:  Mylar covering requires a heat source to attach and shrink.  Many beginners won't have this.  Even domestic tissue, with all its' defects, will be easier to handle.
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calgoddard
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« Reply #32 on: June 26, 2020, 09:58:45 AM »

flydean1 -

Thanks for your input. I agree that covering with Mylar film requires tools and skills that are very unlikely to be available to novices.

I intend my beginner's P-30 to be covered solely with tissue.

The comment at the end of my prior post should have said the following. Using 1/32-inch sheet ribs in the stab would require the use of Mylar film covering to avoid warps.  Therefore 1/16-inch sheet ribs will be used in the stab to permit tissue covering.
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calgoddard
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« Reply #33 on: June 26, 2020, 10:01:18 AM »

A pre-assembly picture of my beginner’s P-30 is attached.  The weight as shown is 25.02 grams. I was not careful with balsa wood selection. The nose block and prop assembly will add at least 10 grams.  Adding the weight of the tissue and dope on the wing and stab, and the weight of the wing saddle will surely push the all-up-weight (less rubber) of the finished model above the 40-gram minimum set forth in the US rules for the P-30 event.  The finished model should come out less than 50 grams, and perhaps close to 45 grams. Nominal amounts of down thrust and right thrust have been sanded into the forward end of the fuselage.
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« Reply #34 on: June 27, 2020, 03:06:22 AM »

Looks nice. I agree with Jim's analysis though. I think she will fly but may be tricky in turbulence etc. In the end I think even rank beginners can handle a simple V dihedral wing with little trouble and the discussion regarding the particular need for more dihedral on FF models is an instructive one to have with any beginner in the hobby. The last thing we want to do is to give folks the impression that dihedral is optional.

just my two cents.

BG
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calgoddard
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« Reply #35 on: June 27, 2020, 02:20:19 PM »

Bernard -

I have great respect for your opinions based on your vast knowledge and experience in the free flight hobby.

You and Jim are probably correct that a flat wing P-30 is not be the best configuration for a beginner.

Right now I have the time to conduct this experiment.

At this time, I don't have access to a flying field and my winder, stooge, blast tubes, etc.

I will go ahead and finish this model in the hopes that I can do some test flights with it in the coming months.

Thanks for your input Bernard.  It is welcome.

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calgoddard
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« Reply #36 on: July 19, 2020, 05:59:56 PM »

The weight of my completed beginner’s P-30 model as shown is 45.5 grams (without rubber).  I was not careful with balsa wood selection during the build. Better wood selection would achieve a weight closer to the 40-gram minimum under the P-30 rules followed in the United States. By way of example, lighter 1/16-inch sheet balsa wood could be used for the tip plates on the ends of the wing and the twin fins on the ends of the stab. This would probably save a couple of grams.

I set the CG at a conservative 57.5%.  The CG is located 2 3/8-inches aft of the LE of the wing, which has a 4 1/8-inch chord. Right now, the down thrust is about 6-degrees due to the generous decalage. The right thrust is slightly over 2 degrees.
 
Low power tests flights in my small local park yesterday showed that this model exhibits sufficient roll stability in relatively calm conditions.  I wore a mask and stayed away from other people who were exercising their dogs.
 
I cannot launch this model at more than 300 turns and 2 inch-ounces of torque in that small park without risking its loss.

When I can test fly my beginner’s P-30 at a large flying field, I will gradually increase to 1000+ turns and 5+ inch-ounces of torque. I need to confirm that the model exhibits sufficient roll stability in windier conditions.  This may not take place for several months due to the ongoing pandemic.

Thanks for reading this post.  Your input is welcome.
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« Reply #37 on: July 19, 2020, 08:24:00 PM »

One way to test at higher torque levels without exceeding small field dimensions is to double the rubber cross section.  You will have to ballast the model to keep the CG the same as with the 10-gram motor.  If you double the cross section of your present motor, the 2 oz/in torque will come up at about 75 turns.  5 oz/in will probably require less than 200 turns.

This accomplishes several things.  First, the increased motor weight and CG ballast will inhibit the glide, shortening the flight.  The higher torque will bleed off very quickly.  Any dangerous tendencies will be revealed but will be of short duration; sort of like a short motor run at full power on a gas or electric model.

I used this to trim my Majestyk to be "safe" at 6 oz/in torque knowing it will be well able to handle the 10 gram motor (2-loops of 1/8).  Best flight was still less than 40 seconds, and well contained in the small field I had at my disposal.
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« Reply #38 on: July 19, 2020, 09:01:02 PM »

Went back to the correspondence.  Ding was flying with a club in the Sacramento area.  Searched the Endless Lift site.  No picture of the P30.

Ding Zarate is a member of Oakland Cloud Dusters. I'll let him know of this thread.

Our web site has one of his designs with tip plates, but it's a more conventional setup.

http://www.oaklandclouddusters.org/Resources/Documents/Plans/Rubber/DingZarate_equilibrium_P30.pdf

--Ates
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« Reply #39 on: November 02, 2020, 01:46:40 PM »

I was finally able to put in some higher power trim flights with my Three Nite P-30 at a beautiful free flight field in northern Nevada. It is about one square mile of flat grass land with no trees.  This flying site is located west of Washoe Lake roughly halfway between Reno and Carson City. It is a landing zone for hang gliders that take off at nearby Slide Mountain (9,000+ feet at its peak).  I can fly model airplanes there seven days a week and it is only a 45-minute drive from my home.  There are no cattle on the site - indeed the area is not properly fenced to keep them from wandering away.  My guess is that the land is owned by the State of Nevada or Washoe County. So hopefully it will not be developed into housing in the future.

I gradually ramped up the torque during the trim flights and added down and right thrust as appropriate.

It was relatively easy to achieve a 2-minute max with my Three Nite P-30 even though I was flying at an altitude of approximately 5,000 feet.  Flights would be longer at sea level due to the increased air density. The performance of my Three Nite P-30 exceeded my expectations. The model has no apparent roll instability issues as some might have thought with no wing dihedral. 

Here is a link to a video of the latter part of one of the flights:
 
https://www.youtube.com/watch?v=hhxdQG2ohJ8

Sorry for the lack of visibility of the model in the video.  It was taken with a cell phone camera.

This video shows some of the glide phase of the flight. I think it catches some down air during a segment of this video because overall the glide of this model was quite good for a 45 gram “stick and tissue” P-30.

I am pleased that I achieved my goal of designing P-30 that would be relatively easy for a novice to construct and still provide reasonably good performance. I am even happier to discover a really good CAT III outdoor flying site that is close by my home and unlikely to be made unavailable for free flight for a number of years. I was the only flier at the site and probably that will be the case most of the time. In fact, I believe I am probably the first person to ever fly a rubber powered free flight airplane at this site. It is apparently rarely used for flying RC gliders.
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« Reply #40 on: November 02, 2020, 03:04:36 PM »

The video was certainly convincing.  Just wondering how it would do in some typical "contest" turbulence.

You're tempting me to do a flat one.
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« Reply #41 on: November 10, 2020, 09:37:30 PM »

I flew a Carney "designed to spec" embryo for two seasons until I lost it to a flyaway. It has a wing with tip plates and a very long fuselage. an ungainly looking airplane ,but a flying machine! it handled all sorts of weather. I was experimenting with an 8 gram motor when I lost it,
yes 4/5 of a p30 motor on 50 square inches!  that gave it an unreal climb after it sorted it's self out. Stablity in the glide was never an issue.
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« Reply #42 on: March 14, 2021, 12:37:19 PM »

Volare Products is now selling a laser-cut short-kit for my Three Nite P-30 at www.volareproducts.com.  In the process of developing and refining the short kit, George Bredehoft had me build a second prototype using the laser cut parts which he meticulously laid out on five different sheets of 1/16-inch sheet balsa wood.  The laser-cut parts went together beautifully and the build took less than half the time it took me to build the first prototype from scratch. The picture attached to this post shows my second prototype.

The two prototypes have essentially the same air frame.  The only significant difference is that the single 1/8 x 1/8-inch main spar of the wing of the first prototype was replaced with vertically spaced upper and lower main spars each measuring 1/16 x 1/8-inches.  These two spars are connected by 1/16 thick sheer webs in the middle three bays of the wing.  While there were no problems encountered with the wing of the first prototype, I felt this design change would add significant strength for minimal (if any) weight gain. Details about test flights of the second prototype and the Volare Products short kit are set forth in the following post.
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« Reply #43 on: March 14, 2021, 12:39:22 PM »

This is a continuation of my previous post.

Test flights last week proved that just like my first prototype, the second prototype of my Three Nite P-30 was easy to trim, had plenty of roll stability, and was more than capable of achieving a two-minute max. The picture attached to this post shows me launching my second prototype at Washoe Valley, Nevada, on March 7, 2021.

The glide of each of my two prototypes is surprisingly good for a P-30. This may be because the tip plates on the wing are reducing drag-generating wing tip vortices. The tip plates also apparently eliminate any need for wash-out in the wing tips. The use of the Neelmeyer airfoil may also be enhancing the glide. I understand that a 10% Neelmeyer airfoil was a favorite of Bill Henn who was very successful at SAM competitions, and later at FAC competitions.

In my exhaustive research I have yet to locate any P-30 design with a flat wing and tip plates that has previously been published and/or kitted. I am very surprised by this in view of the very good flight performance of my two prototypes.

The Volare Products short kit that is available for purchase at www.volareproducts.com includes five sheets of laser-cut parts, a very clearly laid-out full-size plan with helpful legends, and eight-pages of detailed building instructions and flying tips. The plan shows how to incorporate a simple and reliable fuse DT. There are two purchase options: $22 for the plan and laser-cut parts, and $40 for the plan, laser-cut parts, beginner’s parts (dowels, Aluminum tube motor peg, and rubber for one motor), and 9 ½-inch Gizmo Geezer prop assembly.

Look for an article about the development and details of my Three Nite P-30 in an upcoming edition of the NFFS digest.

Beginners now have a P-30 kit commercially available to them which is easier to build than any other P-30 kit or published design yet still yields a competitive rubber powered model airplane.  Accomplished fliers may enjoy the quick build of the Three Nite P-30 that will add a uniquely configured good performer to their fleets.

I hereby state for the record that I have no financial interest in sales of the Volare Products short kit for my Three Nite P-30.  My only hope is that my simple P-30 will provide another vehicle to encourage people to join our free flight hobby.

Thanks for reading my two posts today.  Your comments and feedback are welcome.
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« Reply #44 on: March 14, 2021, 05:24:30 PM »

The attached picture shows the slab sides of the fuselage constructed from the Volare Products short kit.  See Reply #42 and Reply #43 for a description of this new Volare Products short kit.

Each side is constructed from two sections that have been laser-cut from 1/16-inch sheet balsa wood. The sections are glued end-to-end with an interlocking joint and the joint is reinforced with a doubler.  Another doubler is glued over the motor peg location.

The laser-cut oval apertures save about 2 grams in weight.

The front 4-inches of the fuselage have no apertures laser-cut in the same for ease of handling the model and to provide a location for a viscous timer for the DT if that option is utilized.

The fuselage sides have been vertically oriented with their top edges held in a straight line by pressing them against and underlying section of sheet metal sheet with pairs of magnets.  I have long used this Magna-Board XL system from Easy Built Models.

Note the laser-cut notches in the upper and lower edges of the slab sides of the fuselage.  These are mounting locations for the cross-pieces.  Each laser-cut cross-piece has integral gussets at each end that are glued against the inner sides of the fuselage sides to properly space the sides apart from each other and add strength.

The laser-cut parts allow for rapid and accurate construction of the fuselage.

I'll post more pictures as this build of my third Three Nite P-30 progresses.
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« Reply #45 on: March 14, 2021, 07:47:43 PM »

Interesting approach Cal. I haven't tried anything large but I have built and flown modified Darcy Whyte Squirrel's and they have surprised me with their ability to handle a 51/2" prop on a 12" WS.

I was able to trim them to get very fast and steep climbs with a decent glide.

I must admit I was surprised and originally only selected them for their simplicity when working with kids.

Best of luck with your nice looking P30.

John
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calgoddard
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« Reply #46 on: March 14, 2021, 08:54:29 PM »

John -

Thanks for the complement. I have long enjoyed your thoughtful and gracious posts on HPA that are very encouraging.

I currently have ten flyable P-30 models. What surprises me is that the glide on my Three Nite P-30 appears to be competitive with the glide of my high-tech P-30s that have high aspect ratio, under cambered wings. Those thin wings are tedious to build with CF reinforced balsa wood parts and it is not easy to cover them with Mylar film. However they do have the advantages of being very strong, very light, and basically impervious to unintended warps.

My eventual goal of this project was not to come up with a model that could challenge Buddenbohm's Air Shark, DeLoach's Polecat MK 10, Brooks' Boomer MK III, or Berdov's Pirate.

I wanted to come up with a quick-building laser-cut kit for a beginner that would be a good flier. But I now think my Three Nite P-30 would be competitive in the hands of an experienced flier. Plus I think a 9-hour build for a good flier is an attribute.  By way of example, it probably took me twice as long to scratch-build my HOT BOX P-30 (picture attached) which is another entry level P-30. I don't think my HOT BOX P-30 flies as well as either of my Three Nite P-30s. The HOT BOX has a wing with conventional V-dihedral and a flat bottom air foil.  Its wing uses cracked ribs to approximate a traditional air foil shape.

Currently I am building a third Three Nite P-30 with lighter balsa wood so that it can carry one of my RF locators without a serious weight penalty.
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Re: Flat Wing P-30
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flydean1
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« Reply #47 on: March 14, 2021, 10:19:17 PM »

Ding Zarate's quote below:  I was asking him about his experience with end plates only.

Hi Dean,

Yes I have been flying a Squirrel Type P-30s since 10-10-2010 (see Endlesslift.com) and I'm still fascinated with the idea.  In one of the videos of Endlesslift I had noted a stall in that short flight.  In that stall the model came to a stop at a slant to the right.  On the downward movement after the stall the model seemed to straighten itself up to vertical again and it continued into a complete 360 and into the ground.  Now was that the effect of the wing tip  endplates or not?  Maybe?

I think Darcy Whyte has discovered something.

Ding Zarate


So Cal, you  have confirmed the concept is a valid one.  I have some garage/shop cleaning, and renewing my Instructor's Certificate.  After that, I plan a P30 from the Boomer III kit and will build it with no dihedral and end-plated.

When we see the Wakefield...er F1B gang using them you, Ding, and Darcy will be hailed ad pioneers.
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Kevin M
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« Reply #48 on: March 15, 2021, 02:22:12 PM »

I'm very interested in this. Nice design, looks good and appears very well engineered, should be a popular kit. I'm looking forward to more reports as you get to fly it more in varying conditions.
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Indoorflyer
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« Reply #49 on: March 15, 2021, 02:51:35 PM »

Looks like a nice design.  Could not find it (yet) on the Volare site.
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