Goldguy Is Right: Round Flies Better

It's a Nutball without the polyhedral. It's a round Pizza Box Flyer. It's the USAF UFO.

I'm a big fan of the Pizza Box Flyer, but I'm not a fan of the pitch sensitivity. I wondered what it would be like to fly a round one, and I recalled that on the All Things Round thread I'd seen something called the USAF UFO, by the always excellent GPW. Pardshaw built one and loved it. I built mine along his recommendations:

24 inch diameter

1300 kv Blue Wonder

500 Mah battery

He recommended huge elevons, but what does he know? I scaled mine up from the 21 inch plan provided by GPW. I'd show him.

It flew really sweet. It climbs at half throttle. It has a very low wing loading so it's very floaty, but with the throttle up it gets fun. Which was the problem. The roll rate with those little elevons was slow, too slow to get out of hairy situations before smacking grass, and the whole reason you build something like this is to get into and out of hairy situations.

I cut the old elevons out and installed bigger ones. I measured 6 inches up from the rear, drew a line straight across (leaving a 2 inch strip for the tail) and cut new surfaces to fit. The throws are maybe 35 degrees and I've dialed in 40% expo. And the result? Amazing.

It has all the benefits of the PBF without the pitch sensitivity. It's smooth, in a dive or a climb, but it still loops in almost it's own length. It's just as wild as a PBF but it's easier to fly. I love it. Don't think I'm going back.

Pardshaw raves about it, and I think I recall Goldguy saying that "next to a UFO, the PBF" provides the most fun-per-buck. I think I agree.

That huge tail is odd looking but MAN does it keep this thing straight, even in wind. I bet the Pi Yak is a hoot (it's this thing with a fuselage and a functioning rudder). 

The only problem is that when you see it in profile all you see is tail. The wing turns invisible. It's a little disconcerting if you're far away.

Very pleased. It's my new favorite.

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PS: The fuse and tail are all one piece and L-shaped. The fuse on mine is 1.75 inches tall. The tail is 9 inches tall and 4 inches wide. The whole thing is 12 inches long. 

PPS: Built it out of Model Plane Foam, which I love.

Hobby King's Nutball

If you're into scratch building little foam RC planes you know what a Nutball is. For the uninitiated the Nutball is arguably the most significant design to come out of our branch of the hobby. Goldguy knocked it out of the park with this design.

The support thread over at RC Groups is on page 834 and counting for good reason; this is the perfect first build. You don't have to worry about elevons, it has very few steps in its construction, and its polyhedral tips give it a huge amount of stability and thus make it easy to fly. Dial up the rates and you can do silly things with it. A pilot who is bored with Nutballs is a pilot who is bored with life. These things don't get old.

I first encountered the design at Flitetest:

I've made several. Some I've crashed because I wanted to see how far I could push them, and some just plain wore out. I've passed 3 of them along to newbie pilots to use as their first planes. Every one of them has flown great.

Say you're new to the hobby don't want to scratch build it? Getting the new plug and fly version from Hobby King might be a good option. Like scratch Nutballs all of the components are exposed; you can see how everything is put together and what everything does. Even if you didn't build it from scratch you still get some experience learning about what makes an RC plane work. Just glue on the tips, attach your receiver and you're in business. Also consider the fact that HK's version only weighs 100 grams ready to fly (3.5 ounces!) and it's made of EPP, which means it will be crash resistant.

$50. It doesn't get a whole lot cheaper than that, folks. I haven't bought it, so I can't review it, but I like it. I might have to get one for the sheer novelty of ordering an ARF Nutball. It's also smaller than the Nutballs I have known, having a span of just over 18 inches. The original design calls for 20, and that's the only size I've ever flown, but the way this one flies seems very familiar to me.

Here I am with my buddy Albert in some Nutball versus Pizza Box Flyer combat (my Nutball is squarish... I haven't found that the shape matters very much). With the rates up this thing is very agile; with the rates dialed down it's a sweetheart.

So build a Nutball, or buy one. Everybody should have one.

Model Plane Foam

Time flies! It has been too long. Life gets busy.

I just got a load of Model Plane Foam's A-grade stuff, 16 sheets for $60 shipped, and I'm very happy with it.

Lets compare it to Dollar Tree's Adams Redi Board:

Surface Area: Adams =  600 square inches  per 20x30 inch sheet, while MPF has a surface area of 1152 square inches per 24x48 inch sheet. For all practical purposes MPF sheets are equivalent to two sheets of Adams.

Price: Adams costs $1 per sheet, while MPF costs $1.88 for an equivalent sheet if you buy the A-grade stuff ($60/32).

The Foam Itself: At first blush I like MPF better. It's maybe not quite as stiff as some depron I've ordered, and it certainly isn't as stiff as Adams, but there's no paper on it.

Thickness: Both are 6mm thick, so plans designed for Adams ought to work with MPF.

Weight: Adams weighs .19 grams per square inch (source), while MPF weighs .14 grams per square inch.

To calculate MPF's weight we take the retailer's figure of 2 pounds per square foot of density (a 12x12x12 inch cube) and divide by the total number of 1 inch square cubes in that large cube, which is 1728. Then we divide that by 4, because the stuff is 1/4 inch thick. We get a weight in ounces of .005 per square inch of material. This converts to .14 grams per square inch.

Conclusion: MPF has no paper to deal with, it's strong but not as stiff, and it's about 25% lighter. I'm liking it so far... I'll build a plane with it and report back.

RC Groups Park Jet Thread

Here is a link to the park jet thread. It really is a subculture unto itself. Lots of interesting stuff.

Standard Park Jet Power System

There is a strong subculture of park jet enthusiasts which I have only recently stumbled upon. They make their jets out of 6mm depron and they use this standard power system: 2200 kv motor, 30 amp ESD, 1600 mah 3 cell battery and a 6x4 prop. Tis setup will power large models (though not overly large) very handily. It is the best of all worlds, the sweet spot, for park jets.

RC Powers has a parts list and links to suppliers. Dave and Scott also have well researched designs and will sell you the plans for a very fair price.

A huge number of plans can be had for a small donation at park jets.com. A favorite seems to be the Alpha Jet (a very modernist take on the biplane).

The Cheap N Easy by Rcrich

I built this foamy to test its feasibility as a trainer. I am thrilled with the results.

What do I love about it?

• This thing can fly SLOW.
• It's easy to slap together. Build it like Goldguy's Nutball... the only real complication is the prop-and-slot pusher motor configuration.
• It's a Rudder, Elevator Throttle style plane that can do axial rolls.
• It's a larger plane but it still uses the standard Blue Wonder motor, 1000 mah battery and 9 gram servos that EVERY Flitetest aficionado already owns.
• It is STABLE. The Cheap N Easy wants to fly straight and level. I flew mine in high wind with no problems.
• It will hover even on a calm day. You can land it straight down if you get your high-alpha angle correct.
• It literally turns in place.

Here are some points to consider:

1. Rcrich has us balance the plane at the back edge of the prop slot. This is fine for experienced pilots, but I suspect that a beginner will want a more forward CG... perhaps in the middle of the slot, or at the front.

2. The large control surfaces can make the plane squirrely if you don't tame them with exponential. I have 60% expo on the elevator. Of course you could just reduce the throw, but what fun is that?

3. I've used bamboo skewers as pushrods. Take pieces of wire and heat shrink them to the ends. I like to add a dab of CA to the end for added insurance.

4. I've also rubbed Minwax Oil Based Polyurethane into my plane with a paper towel. First I taped all the control surfaces, then I added colored sealing tape, and finally I minwaxed it. I'm very pleased with the results. It's a durable finish and it adds a lot of strength.

5. I wonder if the Cheap N Easy could be included with the swappable series? It flies like an extra stable Nutball, and I think might make a decent first plane.


Links:

My video really doesn't do the Cheap N Easy justice. To watch its designer put it through its paces follow this link:

http://www.youtube.com/watch?v=oVe_gbxG6aM

Time to build your own! Check out the plans at:

http://www.rcgroups.com/forums/showthread.php?t=1261273&page=2

Somebody Built My Little Delta Trainer!

This is so cool! Here's the link.

The Super Easy

I spent last weekend with Dad flying some new pilots on a buddy box. We flew them on Dad's .46 Nextstar and on my PFD Delta. It got me thinking about a cheap dollar tree trainer, a concept I experimented with once upon a time.

This guy may have cracked the problem. His Super Easy is a prop and slot delta wing floater. It is super easy to make and it's highly stable. It looks like a paper airplane, which is kind of fun. I especially like how the electronics are protected from a crash.

I'm interested.

SYMA S107G IS NOW 2.4 GHZ!!!!!

The Syma S107G micro helicopter is now being produced in 2.4 ghz. This means that you can fly it past picture windows or under flourescent lights at will, and you can fly more than two at a time. And the price? $23. We live in extraordinary times, folks. This is now officially THE BEST DEAL IN RC. Buy one immediately.

Here is a link if you would like to get yours from Amazon.

1970's Pattern Nationals

With the resurgence in popularity of classic pattern planes like the Kaos or the Dirty Birdy it's interesting to look at archival footage of the real thing. Click here.

KF Airfoil Wind Tunnel Testing

This young man did a wind tunnel test on a flat foam airfoil, a traditional airfoil and a KF step. The flat airfoil performed poorly all around (no surprise), while the KF produced more drag than the standard airfoil, BUT... the KF step also produced more lift.

In a subsequent video he tests a flat airfoil and three KF airfoils on the same plane. The results are fascinating. Powers RC did the same thing with park jets.

Worth a look.

RC Links Grab Bag: Noob Kickstart And 9mm Foam On The Cheap

Two things for you today...

First: I like how this guy makes stiff 9mm foam out of Dollar Tree Redibaord.

Second, this kid is well on his way to building THE curriculum for new RCA hobbyists.

Project Flight Design Delta vs. Pop Wing

I haven't flown a Pop Wing, but my guess is that it flies better than the PFD Delta. It's EPP and it has a shaped airfoil. How much better, though? Here are some numbers, and it's actually more favorable than I expected:

Pop Wing

Span: 35.4 in
Length: 22.6 in
All Up Weight with a 1200 mah 3 cell: 12.3 ounces


PFD Delta:

Span: 30 in
Length: 20 in
AUW with a 1300mah: 14.25 ounces

My Desert Island Foamy: The Project Flight Design Delta Wing

Every time I build a plane I swear it's my favorite, but this thing might actually be my favorite. It's the Delta Wing by Project Flight Design. The young man who designed it went through 5 or so prototypes before he settled on the perfect dimensions, and let me tell you, this thing is perfect.

What a sweet flier! Fast when you want it to be fast, slow when you want it to be slow... it tracks straight and has a very gentle stall; doesn't fall off and barely sinks. It turns tight; really tight. My favorite thing to do is to fly it up almost too high to see, dive directly down with the throttle cut, and glide it in for a soft landing.

It flies just like the Pop Wings you see on Nitro Planes, but the airframe cost about $4.50 to build.

I built mine completely out of dollar tree foam. I doubled up on peeled foam for the step (3 thicknesses total, and no paper on the step) and covered it with packing tape. I have a Turnigy 1450 Kv motor on one of Dad's Indestructible Motor Mounts, and power it with a 1350 Mah 3 cell battery. Some 9 gram servos, a 30 amp Red Brick speed control, and an Orange Rx receiver ($6!!!) complete the electronics.

At 14 ounces I thought it was going to be porky, but with the throttle off it flies like a slope soarer.

I like the tractor configuration; I don't know why you would want a pusher on one of these type of wings unless you are doing FPV. Maybe there are good reasons.

Check out the build video here.

He has a pusher variant at Flitetest.

The more observant among you will realize that this completely trashes my build schedule. Ah well...

Hobby King Offers $20 Coaxial Heli... 2.4 Ghz!

Here it is.

If this is made to a decent standard, it's the new Syma S107G. It's a Blade Scout at less than half the price. You could fly 15 of them in bright lights past windows and have zero problems.

It includes a full size transmitter, and the battery slides out.

Somebody do a review of this thing!

Here's Hobby King's "review."

Iran's Bavar 2 Flying Machine Gun Boat

Iran is flying 3 squadrons worth of ocean going ground effect vehicles. Armed with a machine gun and surveillance cameras, they can operate in high waves by flying over them rather than crashing though them. Their construction, size and altitude may make them difficult to detect. They top out at 100 knots.

 

Iran claims that they are technologically advanced. Well, their open cockpits and kit plane construction argue against that, but these things are an impressive low-tech answer to our drone fleet. Manned aircraft are cheaper to operate than drones in less developed countries. See Iraq's Cessna Caravan fleet, which function as Predators on the cheap, as an example.

Military analysts mock the craft as flimsy, but if you are familiar at all with the home built community they seem positively robust.

Some sources worry that Iran might strap home-brewed anti-ship missiles on them to threaten Western patrol vessels in the Gulf. It would be a pretty cheap way to sink a very expensive piece of equipment, that's for sure. We 'd obliterate them, of course, but Iranian doctrine isn't to win; it's to make the price of an American victory too high to for us to bare.

This thing pleads for a scale RC model. Goes without saying.

Check out video of this clever little warbird here.

* * *

Image courtesy of the good people of The Islamic Republic of Iran

Young People in RC

 

 

The Problem

 

The average pilot at my local field is over 60 years old. We're keenly aware of the fact; we announce the average age at every club meeting. People get excited when a kid joins because it drops the figure a few years. Still, the fact remains that young people aren't joining the hobby in the numbers we'd like.

The Solution?

 

What to do? I'm starting an RC club at my high school. I teach there, so it's easy for me to put some real time into the project. When we first started up I only managed to snag two real prospects. We were flying simulators and scratch building nutballs and having a ball, but for most kids it seemed like too much work. Enter the Syma Helicopter, the Mini Beetle Quad Copter and the Night Vapor.



At first I let kids fly my Symas, but they didn't take much care with them. Although the Syma is a robust little heli, if it is abused it will eventually break. Kids needed some sense of ownership, I decided, so I bought a bunch of Syma S107G's from Amazon (I have Prime) and sold them at cost to students and teachers. They were gone in a day. Anybody can fly this thing, and it's only $20. What's more, Albert, the student who I taught to fly, learned to fly coaxial helis first and was able to solo a nutball in 6 flights, so the skills are transferrable.

Of course the S107G works on infrared. For the price of two of them you can get a Mini Beetle Quad Copter or a Syma Quad, and those operate on 2.4. They can even fly outside in low wind, and they're very tough. They're easy to fly; rank beginners can hover them in just a few minutes.  This is probably one of the few upsides of hours of video game playing; kids pick up on this quickly. So far two of my Syma pilots have purchased their own quadcopters, and they love them.

Indoor Fun Fly

Our efforts culminated in an indoor fun fly, at which we had 11 student pilots and 3 staff pilots in attendance. Several of the students approached me, wanting to know how they could build a "big" airplane like the ones I fly.

My Father brought his Night Vapor and the kids loved it. All it cost him was a set of landing gear, easily replaced. This thing costs about 2.5 quad copters, or 5 Syma's, but it's a sweetheart. It's easily the easiest plane to fly currently on the market.

Lessons Learned

 

 1. Kids should own their equipment. This promotes responsibility.
2. Have a safety briefing. Make sure kids understand the line of infinity.
3. Discuss RC etiquette. Kids need to know that you do not ask a pilot if you can fly his or her plane. It's rude. Also you don't just grab somebody's equipment and play. Basic manners are important, and people who don't follow them can't fly.
4. Adults, especially staff, need to lead by example (see rule 3).
5. There's nothing like flying a quadcopter through the halls just before passing period to pique a student's interest.

Links

Syma S107G

Mini Beetle Quad Copter

Night Vapor

Cascade Model Aviation Student Club Blog

 

New Club Video

Our high school club held its first event at the 2013 Cascade High School Spring Showcase.

I'll put it on the club blog once I remember the password. It's also submitted to Flite Test.

SloFly 22

I got my micro parts and was all set to build the Sim Sym Sam when I ran across the SloFly 22 on Flite Test. I must have it.

Here is a page dedicated to the design:

http://www.sdparkflyers.com/slofly/

New Club Blog

Visit the Cascade Model Aviation Student Club Blog at:

www.cascadeMASC.blogspot.com