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We had storms roll through Volare Acres this week – Brainstorms! We had rain, too, but coming out of the Indoor Fling last weekend, I was inspired to try several things.
First thing, though, I’m going to talk about flying buddy, Archie Adamisin. Archie is a third generation modeler as his grandfather and father and uncles were (and are!) modelers in the Detroit area. Archie now lives in Kentucky, but has participated in our monthly Indoor contests as his mom and dad still live in the Detroit metro area,
Archie has raised the bar at our contests and he won the hotly contested WWII NoCal Combat event at the Indoor Fling, besting 8 other competitors in 3 rounds of flying. His winning time with his Dauntless was over 4 minutes on the final round.
He and I have been loosely bouncing ideas off of each other in the virtual world. Mostly they are his ideas and I add some thoughts or questions here and there. We had been playing with forming balsa props over the last couple of years, forming them in a 3D printed pitch form. These work nicely, but are fragile. We have used them successfully on NoCals – in fact, his Dauntless has one on it – and I had put some on my Peanut Corsair. I was happy with the performance, but I kept breaking them. We also flew them on models as big as Embryo. His Indoor Embryo has one, but high power and outdoors was rather rough on mine.
Well, this winter, Archie has been working on a new angle: “3D Props” – yes, that’s what he is calling them. He’s a master at layout in the 3D world and has been creating a wide variety of 3D printed props – from the very tiny (2.25″ diameter) to large – 10″ or so in diameter, including a few P-30-legal (because they are for sale) props.
Also legal are his props for Phantom Flash – he has flown his to over 3 minutes indoors. These were verified legal by FAC-GHQ. His “Nickel Scale” 3″ prop is now the standard for this class, as all successful flyers at the Indoor Fling were using his props. (You will see his Nickel prop later in this write-up.)
I have printed some of his props (as part of his “R&D team”) and I asked him for a replacement prop for my Corsair. I told him I wanted a 4-blade with a 5″ diameter, 1.3:1 P:D, and 1/2″ wide blades. You know – for that Scale Corsair look. He sent me the STL and also printed one himself. I put it on my Peanut and flew it around the arena with a happy smile on my face.
As I mentioned before, I’ve been dabbling in Free Flight Electric Scale. I put a Rookie power plant in my venerable HiMax Peanut and have had successful, if limited, flights. The limitations are on the restricted space in which I must fly. I haven’t had a chance to “wind it up” to full power and give it a toss.
But I got to talking to Archie – who also has experience in electric models: he’s dabbled in e-20 FF, but has tons of experience in electric r/c pylon racing. I had two issues with the Rookie prop: 1) it seems small and 2) it is meant for a pusher application. Now, as I say in my info pack provided with the power pack, you can reverse the prop on the shaft and rewire the motor leads on the circuit board – not at all difficult.
But why bother, if you don’t have to? And – how about a larger prop? Archie designed a printed prop at 2.25″D x 2.25″P – oh, and it is going in the “right” direction, too. I printed one and put it on the HiMax. He designed a lower pitch prop, too, but I haven’t tried it.
But I wanted to do a second iteration of Electric. I am choosing models I had retired from competition and this time I selected my Peanut Fike. This gave me two opportunities: test the new prop and test the power pack on what I have imagined is the upper limit for the little motor and capacitor – 50 square inches.
Again, I drilled out the Gizmo Geezer nose button to accept a press-fit of the 6mm motor and I added a platform in the fuselage to accept the capacitor and circuit board. I popped on the new prop and went out in the back yard. Success! It requires a bit more charge (8 seconds vs. 5 seconds) to max out my back yard, but it is a much better flyer than the HiMax. (An aside – I’ve always liked the HiMax design and I have built probably half a dozen of them in various configurations, but the all seem “draggy” and their performance has always been less than anticipated.) Of course, Fikes seem to fly in whatever configuration, but this was pleasing.
So, this Indoor season, I “dominated” the Nickel season, as I was the only one that could get more than 10 or 15 seconds out of their Comet Nickel models. I was able to get 20-30 seconds – per flight – with my Miller Racer. Archie’s 3″ prop helped stabilize the model and it also allowed my to reduce power from a loop of 0.063″ to a loop of 0.045″. My loop was about 9″ long and I could get about 1200 turns in it – and that was good – until it wasn’t.
Tom Sova, an Indoor (proper) flyer from Toledo was showing up at our meets and decided to venture into Scale – and he picked the Comet Nickel Miller Racer as his firs Scale model (shocking – these are twitchy little beasts). Tom surpassed my times and then at the Indoor Fling, I took third place behind Tom (2nd) and Don Slusarczyk (1st). My “dominance” was over.
The biggest issue for me with these tiny planes is the thrust adjustment. My shims are always sloppy and temporary and just don’t work. Here’s a confession: I am addicted to the Gizmo Geezer nose button. As Eli Manning says “I put that s&!t on everything” – except tiny planes. They are just too big for tiny planes – in diameter and weight (1g).
Well, the brain was storming this week and I came up with a solution. I have developed the VPS Lightweight Adjustable Nose Button. There’s no secret in the inner workings and I fully acknowledge that I am standing on the shoulders of the giant that is Orv Olm.
Working through Thursday and Friday, the ideas just kept popping and I now have four iterations of this little gem: generic, a custom nose block for my Miller Racer, Phantom Flash, and (something I’ve been wanting for YEARS) NoCal. The generic version plugs into a 1/8″ hole (the standard I cut for my kits – based on the Peck Nose Button size) and weighs 0.34 grams – 1/3rd the weight of the Gizmo Nose button!
The printed nose block with integrated adjustable nose button allowed me to remove all the ugly shims off the nose of my Miller Racer and produced consistent left hand climbing circles of 20+ seconds until I popped the motor.
Neither the Phantom Flash nor the NoCal have been installed yet, but I expect great things. The NoCal version is 0.4g and the PF is 0.5g.
I have really been wondering if I should even mention these, but excitement (and pride) got the better of me. I do not know if I will be selling them – “why” you ask? Well, they seem to print ok (sometimes small parts can have a rather high rejection rate), but the real reason is that they take about 10-15 minutes each to assemble. So what is the cost? Ten minutes to print, 10 minutes to assemble – that’s a lot of time – and I don’t want to saddle myself with producing 100 of these (I like “inventing” but “production” not so much). They take 12 holes drilled in four different sizes, three holes “reamed” and three holes tapped and then assembly and gluing. One thing is for sure – they won’t be any less than the Gizmo Geezer nose button.
So, it has been a busy week! Now I’ve GOT to get back on the Focke-Wulf 189. Essentially, all that is left is to cover and assemble it. I’ve got to get it done before June due to family events in the beginning of June.
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Three new products: Peanut Electric Power Packs and Asuka Tissue in Blue and White.
Firstly, As I have run out of Esaki, I now have Asuka Tissue in White and Blue (Black is on back order). The white is Bright White and the Blue is very close to Esaki Blue.
Next, I have taken delivery of the Electric Power Packs from WSAT in the Netherlands. These are the power packs in “the Rookie” model. I have used for Peanut Electric Free Flight.
Here is the product link.
Here’s a video of a test flight on a rather breezy day.
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I’m not a big P-30 competitor; I only fly in 2 or 3 informal P-30 events a year – if that many. However, I love Rubber-Powered Free Flight and when I see a model with style, I like it, whatever the event category. If it has twin tails, I’m usually hooked. If there is some “swoopiness” beyond mere basic functionality, that’s a definite plus.
So when I’ve seen photos of Omar Grassetti’s “Meteoro” P-30 online, I was attracted to it. I contacted Mr. Grassetti (he’s in Brazil, but “online” is just like around the corner) and he emailed me the plan and gave me permission to kit the “Meteoro”. I drew up the parts over the winter and built the model last week (started it on Tuesday, finished it on Saturday).
With a geodetic wing and tail and sheeted fuselage, this builds to a VERY strong P-30, mine is a little heavy at 50+ grams. Mr. Grassetti indicates he designed it for windy conditions. With nearly 125 square inches of area, it should have no problem soaring into thermals.
I adjusted the wing for best glide, gave it 50 winds in my back yard, and watched it climb, transition and glide clear across my yard into the woods. I am sure this will get up and go with the best of them – or at least, with the best of who I fly with! I hope to give it a real test this weekend, if the weather cooperates.
You might notice that this sport model is not in my standard Black/Red/Yellow livery for sport models. That is because There is a certain cartoon that is entitled “Meteoro” in Spanish – Speed Racer. So I’ve colored this model like the famous Mach 5 and even integrated the “M” into my model’s markings.
I’ve made Mr. Grassetti’s drawing fit better on my printer, added some comments, translations and annotations, created a supplemental instruction sheet, and produced 6 laser-cut parts sheets. You will have the option to add a Gizmo Geezer P-30 Prop Assembly.
You can find the Short Kit HERE.
Here are some build pics – not many as it built fast.
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It seems like forever since I posted, but the calendar says its only been 10 days. I did take a bit of time off to visit my brother in Alabama. Then, I had to concentrate on filling orders from those days off (still not all caught up). Also, I’ve been a bit stalled on building.
I had one boom of the Jumbo FW-189 done and – part of the reason for the building stall – I had a particular jig set on the building board to put the boom sides together. I didn’t want to tear that down because I knew it would be better to leave it and build the second with it rather than tear it down hope that I could put the second boom together the same way with a different jig.
So, nothing on the building board changed. Therefore, I could only build if I didn’t disturb that setup. And the only way to do that was small projects. I think I did a JetCat between building “booms”. Haha, no building booms so far this year; I’ve been pretty slow.
Anyway, I decided to build that second boom this weekend. The jig worked great. I started on Saturday and – slow and steady – finished up on Sunday. Now, I just need to build the fins and a new, finalized, cabin and I can shift gears to the second half of any build: covering and final assembly.
I’ve been slowly working on another project. This one has been on-going for years – since at least 1994, maybe longer. It is one of my favorite planes – Johnny Livingston’s 1933 Cessna CR-3. This will be an 18.5″ span model. Why that size? That’s a slightly-involved story.
A few years earlier, I had built Tom Nallen’s Livingston Monocoupe Peanut model. That got me into researching the Monocoupe, Livingston, and the CR-3. I learned that over the years, Livingston had done many, many successive (and successful) modifications to the Monocoupe and it became a very potent race plane. He then replaced it with the CR-3. He did two things that influenced me: 1- the wingspan of the Monocoupe ended up pretty close to 24′ – which would convert nicely to 24″ – making a nice model, and 2- he took the motor from the Monocoupe and had Cessna build the CR-3 around the motor. The CR-3 came out close to 18.5′ span, so continuing with a 1′:1″ scale, 18.5″ would be the size for the CR-3 model. Wouldn’t it be great to have models of Livingston’s racers; the Monocoupe and the CR-3, in the same scale? (P.S. I have collected 13 pages of photo documentation of changes Livingston made to the NR501W Monocoupe over the years he owned it – too much?)
I still have plans to do both, but for some reason, I’ve pushed the CR-3 much closer to the front of the build list. I have been re-working the old plans for years. I hope I am moving in the right direction. The old plan certainly had potential: Paul Boyanowski built the prototype back in ’95 and it flew great, winning its first contest.
Anyway, how much nose weight will the big, round-engined, short-nosed model need? I am hoping its around 10 grams. It is completely backwards to start a build there, but here is why I ask. Here is another project that worked out this weekend – the dummy Warner Scarab engine for my 18.5″ model.
It all started with this photo of the original nose of the plane. Notice the simplicity of the engine installation: simple cylinders, a simple cover over the crank case, and simple baffles between the cylinders. I like simple – and usually can do simple.
Next match the simple real to the simple model. I only need to do half an engine – the front half. Figure out how to lay out the cylinders and the crank case and how to integrate a nose plug into it. Not terribly difficult (remember to keep it simple). All that was left to do was to convert the two-dimensional line drawings into 3D printed parts.
I made one and it ended up about 10.3 grams with the Gizmo Nose Button front half. I decided to try again, thinning the parts as much as I dared to make them lighter. I saved over a gram on just the seven cylinders and 2+ grams overall. Attempt #2 weighs 8.1 grams. I need to make a new nose plug and I might be able to trim a little off of that, too.
I will admit – that’s a funny place to start on a flying stick and tissue model. Maybe I will get to the rest someday!
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I am a dedicated rubber-power guy. I don’t do gas; I’ve thought about compressed air and CO2; and electricity just seems to be too hard (assembling circuitry isn’t for me).
But a year or so ago, Vincent Merlijn, in the Netherlands, put out a foamie Free Flight kit he calls “the Rookie”. This looked simple: the motor and circuit is pre-assembled, the storage is a capacitor soldered to the circuit board, and you simply charge it with a 3- AA Battery unit. Plug the battery pack in, wait a few seconds, unplug and launch. What could be simpler?
Immediately, I thought of powering a Peanut with this unit and ordered some. When they arrived, I took a look at them and set them aside. I was still a little intimidated and unsure.
Well, yesterday, I decided to do this project and try to get an existing Peanut retrofitted with the drive train and give it a test. I chose my Peanut HiMax. The 10g model never really flew like I wanted it to – probably a result of an improperly matched prop and rubber combo. And, unless they max regularly, high-wing Peanuts are generally not competitive in FAC Peanut.
So, I took the model off the pile (of old models – yes, it is a true pile of models; one of several around the house) and started to do surgery. The first step was to mount the motor. I measured the diameter of the motor (0.237″) and selected a #1 drill (0.228″) and a new Gizmo Geezer nose button and carefully drilled out the front half of the GG button.
This allowed a press-fit of the motor into the nose button and I could swap out the existing GG nose button for the now-electric nose button on the HiMax nose block. I used the GG nose button because I love the how it makes thrust adjustment so simple. If it works for rubber power, it will work for electric power, too.
Next was mounting of the circuit board onto the model. A little bit of thought had to go into this. I wanted it as far back in the model as practical (the model was nose heavy). Also, the charge socket had to be accessible and I wanted it to be on the bottom of the model. I knew the charge system was “instant-on” – once I unplug it, the motor is going full speed and I need to launch. So I had to consider exactly how I was going to do this (hold the model with my right hand where I would to launch, plug in the charger with my left, unplug and toss).
I cut a hole in the tissue, and made a sheet base to hold the circuit board. Then I ran the motor to the nose and glued the board in place with CA. Through some trial and error, I glued the noseblock in place and just had the GG button as the removable part for assembly (temporarily removable – friction fit).
My first venture to the back yard was a 50/50 success: it would take a charge and powered flight was achieved, but I did a terrible job of solidly mounting the circuit board – the insertion force of the charger broke the mount. Back inside and re-engineer the mount. It took some time, mistakes were made, but I now have a solid mount.
After a couple of partial charge flights, I was able to get a climbing turn dialed in and managed to fly off my tiny field into the surrounding pine trees about 30 feet up. After much persuading with my pole, the model came down, but suffered a good deal of strut damage.
I now have an electric-powered Scale Free Flight model! The power unit weighs in at about 4.5 grams. This was a 10 gram model so all-up weight is now 14.5 grams. With 32.5 square inches, this works out to be a 0.45g/sq.in. wing loading – not terrible.
I will say this: for all of my worries, this was an easy project. Of course, except for the new thrust settings, the model was already trimmed.
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I decided to take a short break from my Jumbo Focke-Wulf to build a tiny Old Timer – the Fleetwood Flyer. This was one of seven “Victory Models” designed by Louis Bucalo in the war years. The wing is the same dimensions as the Shaft, but has a different dihedral setup. This model was published in the August 1943 Air Age magazine.
It is a very quick build with the longest part being the amount of time it takes for the rolled tube fuselage to dry (one day). One curiosity was how to attach the single wheel landing gear. Here you can see the original plan and one of the article photos of the prototype. Note the photo seems to show a double wire strut.
I will provide two sheets of laser-cut parts: one sheet (1/16″) has all of the ribs, the wing tips, trailing edges, fin parts, wheel discs, and wing pylon. The other sheet (1/32″) has the tail cone, the tail winglets, and the blank to roll the tube fuselage. I will also be providing the 3D printed LG saddle.
I did move the pylon forward to better locate the CG properly and efficiently. The new, optional location is shown on the plan.
Below is a short video of a test flight. It doesn’t make 20 seconds, but you can certainly see the potential. I was running out of flying space on the breezy day and didn’t want to push my luck.
This model qualifies for FAC events: 2-Bit, OT Fuselage, and Victory Models (Pinkham HandbooK). I will be flying it as my 2-Bit model at the local Cloudbusters events this summer – until it flies away, of course!
You can find the product HERE.
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My recreation of the Comet Fokker D.vii Dime Scale kit A26. I have had this kit on the drawing board list for several years and I finally bit the bullet and did it up this winter. I finished the plane in January, but weather prevented me from test flying it until today. I was able to get some successively better test flights out of it with a high time around 38 seconds on roughly 600 turns on a loop of 1/8″ rubber. The prop is a Peck-style 7″.
The tissue is representing Lothar von Richtofen’s plane. Of course, for Dime Scale, you can simply go with Comet’s recommendation – all red. This tissue template is available for free download on my Tissue Page.
You can get the Short Kit HERE.
One of the things that worried me was mounting the wings. I’m not a builder of biplanes, so my experience is limited. I designed a jig to hold the wing in place while the struts were mounted. You can see it in the build photos below.
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IF YOU ORDER 5 OR MORE SHEETS OF ANY COMBINATION OF DENSITIES YOU WILL RECEIVE THE “NORMAL” PRICE.
Each sheet (1/16″ – 24″x3″) is weighed individually, the weight in grams written on the upper left corner, and then sorted according to the chart below. This balsa is clear. Sheets with holes has been removed (you will not receive holes). Some sheets may be warped and some may have 1″ – 2″ cracks in the end (less than 10% of stock). No effort will be made to select outside of the Density options. Do not request C-grain – I do not receive C-grain, although you might receive a sheet with B-C grain in your selection. All is A- or B-grain.
If there is a demand, I can get 1/8″ Contest Balsa, too (this is nice for small Glider wings).
Shipping will be in a 24″ box. IT IS PREFERRED THAT YOU DO NOT ORDER THIS DELICATE BALSA WITH OTHER PRODUCTS, ESPECIALLY HEAVY PRODUCTS LIKE RUBBER. IF YOU DO, AND DAMAGE TO THE BALSA OCCURS IN SHIPMENT, THIS IS YOUR RESPONSIBILITY.
I prefer not to ship single sheets. Therefore the single sheet price will be extremely high compared to multiple sheets. Basically, five or more sheets (any density combination) will have the “normal” price, and the single sheet price will reflect a packaging surcharge (roughly 2x the “normal” price per sheet).
IF YOU ORDER 5 OR MORE SHEETS OF ANY COMBINATION OF DENSITIES YOU WILL RECEIVE THE “NORMAL” PRICE.
“Normal” Pricing per sheet (orders with less than 5 sheets of any density combination will be double the price per sheet):
My supplier assures me that there is plenty more available.
Find it HERE:
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Trying to work two short articles into one…
PART 1: Gloster Meteor
In the middle of my building doldrums, I put together this small JetCat – a 10″ span Gloster Meteor. I thought about a Canberra, but everybody does a Canberra – and the Meteor has very similar proportions.
Over the last few JetCat builds, I’ve been working on a couple of things:
First, instead of mixing 1/16″ sheet and 1/32″ sheet, I am settling on LIGHT (6 lb or lighter) 1/16″ and sanding it thin where I want it thin and leaving it thick where I want strength. This has been working well, I think. I am making fuselages from three layers of 1/16″. To increase strength in these laminations, I embed a carbon fiber strip in the center and cross-grain the three layers as much as practical. These three things (laminating, carbon fiber, cross-graining) make for a light and stiff fuselage.
Second, I’ve been working on a modular wing structure. It is really hard to supply very light 3/16″ sheeting for wings – hard meaning supply is short and expensive for Production purposes. So I am working toward providing the front 1/3rd of the wing in thick balsa and the rear 2/3rds will be 1/16″ sheet and ribs, and sometimes spars. One downside to this is the need to cover the wing with tissue. If you’re doing printed tissue (I highly recommend this for JetCats) then it’s no big deal to cover the wing.
One last chit-chat about this model (and some of my other JetCats) – why are you building small at 10″ span??? well, that started with my Ohka – and the fact that the standard size for sheet balsa is 3″ wide. So, while I’ve been doing full-sheet wings, I’ve been limited to 3″ chord wings. Another limitation – I try to not exceed 14″ on the sheet – so this has limited Fuselage length. I am working on joining techniques to work on longer fuselages. The last thing – it is just easier to design and build a smaller model, especially for testing. I am pretty sure I will be building a larger meteor – around 15″ span. That will take completely redesigning all the parts.
Anyway, the photos show some of the construction. Now, on to a different discussion.
PART 2: Chalking Tissue
One “thing” about printing tissue is that the colors are not very dense. This is because tissue is rather translucent. When you cover sheet balsa with white tissue the resulting color is basically balsa-colored. You can paint the tissue, but this gets heavy. One way to improve the colors, but add virtually no weight, is to chalk the tissue. I am not going to go into a ton of details on this, but just show you some of the results. The tissue on the Meteor was white tissue that was chalked prior to printing.
I use Pan Pastel chalk (white in this case) and a folded paper towel on a hard surface (wooden table). I fold up the paper towel to make a swab which I rub on the pan of chalk and then rub this into the BACK (rough side) of the tissue. I rub WITH the grain of the tissue. I’ve seen others dump chalk dust onto the tissue and rub it in, but I find this method wastes much less chalk. Still, this can and will get messy. White chalk isn’t so bad, but I still have red “stained” stuff floating around from when I did my red Cessna Cardinal last winter.
Check the photos – you can see the difference between the chalked and the plain tissue.
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Trimming the Model, that is; keep your models away from trees!
While I have a degree of success in getting models to fly, I do not consider myself an “expert”. After 30 years of flying Free Flight, I still have a good degree of uncertainty when it comes to making my models perform as I think they should. I go to many contests and wonder how “the greats” do it and why don’t my planes fly that way.
Today, I will outline some of the things that I have done to make planes fly. It won’t be “everything” but it’s a start. Keep in mind, I still shake my head – and scratch my head – when I encounter a plane that is misbehaving. And this happens quite regularly – almost with EVERY model I build. Today I am going to cover three models that I was flying at most recent Cloudbuster indoor contest just last week.
I took the model out of the box, wound it up and got a 48 second test flight – GREAT! Maybe the best flight to date, although it was climbing dangerously high and getting close to the rafters. I wound up again and called for a time and I had NO success – the plane nosed up, stalled, fell off, and dove for the ground, cracking the propeller.
As I fixed the propeller, I notice one of the tail struts was loose. I did not fix it and it isn’t critical to flight. Since it was stalling on launch, I gave it more down thrust, and added clay to the nose (I should not have to do this – the model was flying well). I wound up again and gave it a gentle toss and had the same experience. This was a very stable model last month and even during the initial test flight that day? what had happened? I picked up the model and saw the wooden prop was broken in half – no more test flights that day.
Fixing it at home, I discovered what I think was the problem – and it was due to laziness or something even worse – careless disregard. While the prop was curing, I focused on that tail strut. I discovered that the horizontal stab was about 3/8″ forward of where it should be. The h-stab and the fin have complementary notches and slide together and are then glued in place. Later the tails struts are glued in place. Here is where the carelessness comes into play:
I had not glued the h-stab to the fin. My post-crash analysis reveals that the h-stab would slide forward under a moderate sudden stop (inertia). Since the tail struts are a fixed length and glued solidly to the fin and the fuse, they would act as a pivot point – and force in a slight amount of negative incidence (up elevator). This would cause a nose up on launch that my chunk of clay and twist of down thrust could not overcome.
Lesson #1 – always solidly fix your surfaces once you have a good-flying model. I don’t even do adjustable tails, so there was absolutely no reason I should not have glued that in the first place. This cost me damage to a good-flying plane: I broke the propeller, cracked the trailing edge of one wing, and tore the tail strut loose.
Lesson #2 – if your plane suddenly misbehaves, THERE IS SOMETHING WRONG. Do NOT continue flying it until you give it a full and critical examination.
Last week, I devoted a good 30 minutes or so to getting this plane to fly I stopped when I ended up with a cracked longeron and broken glue joints all along the length of the fuselage. This was not surprising considering how the plane tumbled when the flight was over. There was no landing with this plane – only crashes.
A couple of times I was able to get the model well up in the air, seemingly flying well. That is, until the power was low enough that it wouldn’t pull the plane around. Then the nose dropped. If the power came off under 10 feet, it simply looked like a steep dive into the ground. If the power came off at 20 feet, then the steep dive turned into a literal outside loop, with the model going beyond vertical before hitting the ground – hard.
The VAA (Volare Aviation Administration) review reveals that the h-stab is way too small on this model. If you recall, these 20″ Comet Dimer short kits are reproductions of the Comet kits – they event come with the original Comet Plans (well, downloaded scans, which are full of scan-upon-scan errors in addition to whatever initial design problems there were).
Archie Adamisin and I have done analysis on the six models. The Taylorcraft, Akron Funk, and the Spartan Fighter all have h-stabs that are too small. These produce models with TVo values under 0.4 – in the red zone. and this is caused by tails that are too small – these three will need the h-stab enlarged to 120% to give you a realistic chance at flying. Strangely – very strangely – the North American, the Vultee Attack and the Allied Sport all have TVOs well above 0.5 (0.6 will product a very stable model when properly trimmed).
I have added sheet wood to my h-stab on the Spartan and will resume flight trimming on this in January.
Lesson #3 – always check your design before building. If I had not done the quick-and-dirty kit production and done my traditional draw-calculate-adjust-build-fly process, this would have been revealed. Imagine how many Comet Kids had similar frustrations and just smashed their models.
Lesson #4 – How to launch a “floppy”, short-coupled, filleted model – hold the nose just in front of the wing to launch (not behind the wing). This it much like throwing a dart. Grasping in front of the CG results in much more consistent launches than grasping behind the CG.
Comet 5¢ Scale – 3 fliers
1st – George Bredehoft – Miller Racer – 81
2nd – Mike Welshans – Cessna – 14
3rd – Winn Moore – Cessna – 8
Now, I don’t know if Mike actually totaled three flights and I am sure that Winn only flew one flight. These little things are tricky. I have found the Cessna especially tricky. I believe that Mike built his from the Comet plans while Winn and I built our Cessnas from my short kit. My short kit followed the advice above and enlarged the tail 110% to produce a reasonable TVo of 0.65.
My Miller Racer is the more stable of the two models that I have built, so I flew that. My score is the total of three flights plus 11 bonus points (10 for low wing, 1 for landing gear down – Dime Scale bonus points).
Now I am not going to profess to know how to make these fly, but I will tell you about this model. The tail is enlarge 120% over the Comet plan. It has a Comet 4″ prop blank, cut down to 3.5″. I use a loop of 1/16″ rubber. On my 28 second flight I put in about 1500 turns. It flies right under power. The glide is not much of a glide; more like a gentle fall. The prop is not freewheeling, so it just kind of brakes and spins, brakes and spins. Oh, and there is are several degrees of downthrust – the nose block is shimmed about 1/16″ at the top.
I think there is a little more left in the tank in this model. I think that I will try a loop of 0.40″ or 0.045″ – trying for less power and more duration. With 1/16″ it takes off hard. The down thrust pulls it down for a time but eventually it climbs. Along with pulling it down, the initial flight is much like a bumblebee – darting all over the place. I launch with the plane banked to the left, maybe 25 degrees or more. This is done to the torque roll ceases about the time the model is in level flight.
Lesson #5 – I don’t know if the above will work for everyone I just seemed to luck into it. I feel like I luck into a lot of success. But, being that there is a lot of success, it could be argued that not all of it is luck. One thing I know has helped me immensely – that is the Gizmo Geezer adjustable nose button. Much like Eli Manning and Frank’s Red Hot sauce, I put that s**t on everything (but not the Nickel kits – they are too small). This is not a product placement; I don’t care if you buy them from me or not – but you will have a much easier time trimming your thrust settings if you use an adjustable nose button. I also use Gurney flaps, clay on the wing tip, and huffing and twisting the wing panels – anything to get my models closer to the perfect flights that Tom Hallman and Wally Farrell have.
OOPS – LESSON #6 – (this will make all of your trimming easier) – BUILD LIGHT. Build lighter than you think you can. Most of our models are over-built, structurally. Do NOT build them to survive a crash; build them light to avoid crashing. The Spartan Fighter above survived many hard landings because it is light. It only weighs 18.5g. Shoot for wing loadings under 0.4 grams per square inch and you will be rewarded. If you can get under 0.3 for Peanuts, that’s even better.
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