Showing posts with label carbon fiber. Show all posts
Showing posts with label carbon fiber. Show all posts

Wednesday, July 10, 2013

20 Pound Carbon Fiber Float?

Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!


Hey Eugene:

While nosing around in the Belite shop earlier this evening, I noticed that they were preparing to pull the wraps off their new aircraft floats.   It is clear they plan to announce at Oshkosh:  but at what price?

I was able to gather some basic technical information, and also take some pictures, which I've pasted below.

The note said:

  *  19 pounds, 13 ounces as shown (still missing a couple of attachment hardware fittings)
  *  Up to 3 layers of Carbon Fiber cloth overall
  *  Carbon Fiber over foam construction
  *  Pre-cut foam pieces
  *  Inexpensive
  *  Final all up weight estimated at 22 pounds (straight); 35 pounds (amphibious)
  *  Superior to earlier Belite and other aluminum floats (much easier to construct; inherently more waterproof due to foam design)
  *  620 pound maximum gross weight
  *  Belite will be selling float kits for a special price during Oshkosh and shortly thereafter

These are clearly a significant product offering for experimental aircraft... looks to be a game changer for anyone who wants to fly off water.  If Belite has truly pulled off a carbon fiber composite float which sells for a reasonable $ amount...  wow.  That will be so cool.

The float in the following pictures was not quite complete.  It needed some sanding and some other stuff, but it sure looked like a float to me.

Your Friend,

Billy Bob.

P.S.:  Have a look at these pictures:

Carbon Fiber Float from Belite

Carbon Fiber Float from Belite

Carbon Fiber Float from Belite

Carbon Fiber Float from Belite

Carbon Fiber Float from Belite
Special note to Mickey:  thank you for encouraging me to think outside the box.

Saturday, December 29, 2012

Carbon fiber stabilator; amphibious Belite?

Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!


We've been working on our carbon fiber processes... and in anticipation of some absolutely crazy stuff in 2013 (EG, an amphibious version of a Belite, for which we already have a firm order with deposit), some additional weight savings are necessarily on the development plate to accommodate the big amphibious floats in a legal Part 103 Belite ultralight aircraft.

So here's a sneek photo of Belite R&D:  a carbon fiber stabilator (combination elevator / horizontal stabilizer).

Carbon Fiber Stabilator, Lucky and Chance check it out
The important technical factors are:

Span:  about 100 inches (2.54 meters)
Chord:  30 inches
Effective area:  19.16 square feet (about 1.78 square meters)
Construction:  Carbon Fiber
Weight, as pictured:  about 4 pounds
Target weight, completed assembly with covering:  about 5.5 pounds (2.5 KG)
Airfoil:  NACA 0012, symmetrical
Target load capability:  approximately 240 pounds lift, representing full control deflection at yellow line speed (62mph)
(all information subject to change)

Benefits:

* Reduced drag - elimination of stabilizer support wires; lower coefficient of drag in cruise
* Reduced weight -- should save around 6 pounds (2.7KG)
* Better authority on takeoff roll (get the tail up faster) and better authority on landing (better flare at lower speeds, allowing safer landings and lower speeds)

Downsides:

* Expense of carbon fiber
* Engineering time
* Risk in testing

All the parts in the photo were designed on our CAD software and 'printed' on one of our CNC machines, the ShopBot.  We also manufactured our own carbon fiber panels, which were cut on the ShopBot in the various shapes.  We purchase the carbon fiber spars from a vendor.

The carbon fiber panels technical specs are as follows:

3K woven fiber, one layer each side
1/8" wood core
West Systems epoxy
Vaccuum bagged on glass

The final thought to chew on:  each carbon fiber rib weighs about 2.1 ounces...  that's 60 grams.





Tuesday, January 24, 2012

How to laminate carbon fiber to plywood

Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!


In our Belite ultralight aircraft, we occasionally make and use a carbon fiber / plywood laminate.  This makes a very nice looking and strong panel, yet is very thin.   It is capable of holding a lot of load when suspended across a frame, for instance, a seat bottom.  (Double sided applications would probably be used with other cores than thin plywood.)

I recently made some of this magic thin carbon fiber / plywood.  I documented the production steps so you can see how we do it.

In order to do this, we'll use some thick beveled glass, tacky tape, a vacuum pump and some vacuum tubing, bagging film, peel & ply film, fluffy cloth padding, epoxy, and of course, -- carbon fiber and plywood.

Let's start with a nice sheet of beveled plate glass.  We've cleaned it thoroughly (I mean it, thoroughly!!!) and have lined the edges with tacky tape.  It has been waxed, then the glass has been sprayed with film release, and I've run some plastic vacuum tubing along one edge, secured with tacky tape as well.

Warning:  carbon fiber and epoxy and glass can be nasty stuff -- always use breathing protection, along with protective gloves.  Use these instructions, as always, at your own risk.

Let's get going...

Plate glass, cleaned and prepared for use.


Thursday, October 27, 2011

Aluminum / Carbon Fiber Spar Loading to 6Gs -- Stunning Load

Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!


I have some really stunning load test pictures of our aluminum and carbon fiber spars.  But before we get going on them, here is some necessary preamble, given our recent fantastic showing on MythBusters:

If you are looking for Belite Aircraft's production photos from MythBusters, click here.  We were thrilled to be part of the "Duct Tape Plane" episode!

If you would like to follow James' tweets, @jamespwiebe is the handle to find on twitter.

If you would like to go to the main Belite Aircraft website, here is the link to follow.

Now, on to the spar loading.

Extremely long time blog readers may recall my tests of carbon fiber spars a couple of years ago.  I wanted to repeat that testing, but this time I wanted to test both our current aluminum spars and our carbon fiber spars.  And I was pushed to increase the load test from a 4G test up to a 6G test, which I did. (Thanks, Mike!)  Also, the length of our spars had increased from 11.5 to 12 feet, as we've increased wing span (and also the wing chord.)  And we had switched vendors for both the aluminum spars and the carbon fiber spars. So it was time for another test, and time to push to new limits in our testing.

This is a simple spar loading test, not a wing loading test.  Of course, the airplane has two wings and each wing has two spars.  We make an assumption that each one of these four spars is 'carrying' one fourth of the total weight of the airplane.  Since our gross weight of our Belite is 550 pounds, the 6G loading of the entire wing structure is 3,300 pounds -- more than 1.5 tons.   Therefore, the per spar loading is 825 pounds.  That's a lot of weight for a single spar to hold.  (The aluminum spars weigh 7 pounds; while the carbon fiber spars weigh 4 pounds, so they are capable of supporting 100 to 200+ times their own weight.  Wow!)

The distribution of weight on the spar loading test spread the load over the length of the spar, with weight added at each location where a rib would be attached.  Also, the spar is supported at the root (where it attaches to the fuselage) and at the strut attach point (where a strut would transfer load to the fuselage).

So here's a photo of the outcome with the aluminum spar test:

6G Spar Loading Test on Ultralight Airplane (Belite Aircraft)
And here's some individual shots:

End Section of the aluminum spar -- one of these rib/weight locations is overloaded, even for 6Gs.

Mid Section of the aluminum spar

Root Section of the aluminum spar




We also did the same test with a carbon fiber spar.  Here's a photo of the outcome:

6G Load Test on Carbon Fiber Spar
The carbon fiber spar is covered in a protective plastic film.

I accidently overloaded the aluminum spar on the second to last outboard rib position, so I labeled the aluminum spar photos 6G+  :-)

The aluminum spar showed absolutely no bend after the weights were removed -- it returned to a perfectly straight attitude.  In other words, this wasn't close to being an ultimate load test.  There's lots more strength hiding in Belite's spars.  Likewise with the carbon fiber spars -- the bend is very mild in the above photo.

Who knows how much more it could hold before it would snap?  (This test does not cover other elements of the wing design, such as the lift struts, ribs, etc --- that work is saved for another day.)

IF I WAS CHOOSING, I would prefer the carbon fiber spars in my own airplane, (they are a $2200 option) but the aluminum spars prove to be an economical and beefy answer as well, albeit at a weight penalty of about 11 pounds per airplane.

Thursday, July 1, 2010

How to make a Carbon Fiber elevator which weighs less than 3 pounds!



I am planning to give a forum at OSHKOSH on how to make a Carbon Fiber elevator.  PLEASE PLAN TO ATTEND!  Thanks.

The Carbon Fiber elevator which is depicted here WEIGHS LESS THAN 3 POUNDS!  And it is stronger than steel.

Carbon Fiber offers benefits which make it vastly superior to 4130 chromalloy steel in many applications.  Careful design is required, though, in order to take advantage of Carbon Fiber's incredible strength and stiffness.  Belite's Carbon Fiber elevator upgrade swap is an available upgrade for any Belite (or Kitfox Lite replacement aftermarket) which will provide a lighter part with far higher strength and better aerodynamics.  This part is available in kit form for a price of $350 over the regular elevator.  (You can find it on our kit pricing spreadsheet here as line item #55.  Remember, this is an upgrade price over the steel elevator (which is separately priced at $399.95).  A straight purchase of this Carbon Fiber elevator kit is $399.95 + $350 = $749.95)

Our Carbon Fiber elevator is a direct replacement for the steel part.  It is made from several basic materials:

Carbon Fiber fabric wound tubing (for leading edge / torque spar)
Carbon Fiber extruded tubing (for trailing edge)
Steel horizontal stabilizer connect hardware (qty 2 -- connects to hinge points on horizontal stabilizer)
Central Steel section (connects to hinge point and to elevator push/pull tube)
Carbon Fiber ribs in various laminations from 3 to 6 layers of carbon fiber 3K cloth, over balsa core
3M 2216 industrial epoxy (amazing stuff)
Laminating epoxy
Dacron Fabric

Jumping to the finished part, here is what it looks like:


And here is how to make it:

1)  Ensure Carbon Fiber spar tube is exactly 92 inches long.  Cut with fine tooth saw to length.

2)  Debur, clean and slide the center steel assembly over the spar tube.  Epoxy in place with 2216 glue.

3)  Debur, clean and slide each hinge point over the tube.  Do not epoxy. 

4)  Cut each rib section using a band saw and supplied rib outline.  Cut front circle to match spar tube.  Leave rear portion extra long, excess length will be trimmed.  Carefully cut angle cuts on center ribs; also cut reinforcement segments. 

5)  Cut wingtip ribs and center ribs to exact length. 

6)  Cut trailing edges to length; you may leave them slightly long.

7)  Glue wingtip ribs and center ribs in place to main spar and trailing edges using 2216 glue.  At this point, you have a complete outline of the elevator.  Allow to fully cure (24 hours) before proceeding.  It is helpful to wrap around carbon fiber tube and ribs with masking tape.  This will force glue to exact shape and is easy to pull masking tape off after curing.

8)  It is now easy to continue fitting each rib to exact length requirement.

9)  Glue all ribs in place using 2216 glue.  Glue remaining hinge points in place.  Allow to fully cure (24 hours) before proceeding.

10)  Now all ribs are in place.  Sand excess 2216 off.  DO NOT sand into any Carbon Fiber.

11)  Reinforce all joints using carbon fiber cloth and conventional laminating epoxy.  This is easily done by laying the carbon fiber strip over the edge, with the elevator vertical, and painting on the epoxy.  It is helpful to do the leading edge, allow to cure, then flip the elevator and do the trailing edge.

12)  Trim excess cloth using either a dremel or a sharp razor blade.  If you use a razor blade, it is helpful to do it prior to full cure of the epoxy.

13)  Sand all Carbon Fiber cloth.  Remove every single sharp point.

14)  Cover using Stewart Systems glue and dacron fabric.

Here's the advantages:

a)  thicker profile allows aerodynamic shape
b)  lower weight, of course
c)  stronger
d)  impervious to rusting
e)  It's just plane cool!  Or is it plain cool?!

Here's some more detail pics.  Our kit includes plans and more assembly info.....

Wednesday, June 30, 2010

Wednesday, June 2, 2010

Bunny Hops & Flying POV

I received a call from my daughter earlier today. She's currently a counselor at Camp Quaker Haven and it was the first time I'd heard her voice since she left last week.  She's also our 'corporate cinematographer', and has produced almost all of the videos that Belite has posted on Youtube.

"Hey Dad," she said. "Did you know that I posted another Belite video before I left Wichita?"

No, I didn't know that.

It's great having a cinematographer in the family!  More video to show people what we are doing.

I had taken quite a bit of video, shot from my Point Of View, while flying the Superlite several weeks ago. It does a great job of showing the world flying by while piloting an agile single seat airplane. You can see it here:

Also, we shot some video of our Trike a few weeks ago.  It's just a series of bunny hops, mostly up and down the runway, but it shows the gentle landing characteristics of the Trike. 

(A little off topic:  I flew both of these planes earlier today, in Kansas strong winds.  They handled the wind with no difficulty).

Anyway, here's the video of the Trike doing bunny hops.

The Trike has free castering nosewheel steering.  You turn the airplane by applying either left or right heel brake.  I'm reminded of when I first flew a Grumman Cheetah back in 1978 or 1979:  ground handling works basically the same.

Monday, May 31, 2010

How to configure a Ready To Fly Superlite 50HP ultralight!

I've created a spreadsheet that allows users to select different options to personalize their Belite 254. Do they want a taildragger, or a trike? Do they want a Superlite, or a really light version? What you may not realize is that these are all really the same airplane. The only thing that varies is the option selection.

The spreadsheet keeps track of option selections, cost, and weight. As a result, you can end up with any type of FAR part 103 ultralight that you want!

Here's our base spreadsheet. Have a look:

Wednesday, May 26, 2010

An independent comment on our plane & instruments

From Terry Alley:

I went to BeLite's shop last friday to visit with James Wiebe about changing the engine in my Kit Fox Lite to the Hirth F23 like the one he has in his new Superlite. While discussing the performance of his plane, James had a slip of the tongue and said "you ought to fly that and see what it feels like", I thought he would never ask.

After sliding into the cockpit I took a little time to familiarize myself with his new LED Panel. At first I thought it would be a little confusing trying to read all the lights but once I became familiar with their location, they were quite easy to read and seemed very accurate. I especially liked the Inclinometer and the Turn Rate indicator. Those two may have to find a way into my panel. The altimeter is zero'd before taking off and is only a AGL instrument, but what else would you want in a ultralight. I made several turns into and away from the sun and the LED's stayed visible reguardless of direction and lighting.

Now for my comparison between the original Kit Fox Lite which I have the new BeLite Superlite.

Cosmetically they look the same with the exception of mine having a full covered fuse. The interior, again no changes, other than the panel already mentioned. The only noticable difference in feel was the rudder. Belite has improved their design to use push/pull cables to the rudder. While they make the rudder feel a little stiff, the contol was very positive. Everything else felt the same excpet the power.

My Lite has a 37 hp 1/2 VW which I really love except for takeoff performance. On a hot day it will make you pucker up if you have to climb over some trees on takeoff. But the cruise is a nice 65 once you get there. The Belite had the new Hirth F23 opposed twin 50 hp. When I lined up on the runway and added power before I could look down to see what the RPM was, I was airborne. Not only airborn but I continued to climb at 50 mph and at a pretty steep angle of attack. Needless to say I was impressed.

After making some steep turns and doing a couple of stalls I concluded this new bird has the same great flying characteristics as the original Kit Fox Lite (when I say original that is what I mean as mine is serial #001). I decided to test the new spring shocks that James had just added to the gear that day. This a great replacement for the bungees (which I have had one failure on). I came in across the fence at 50 and let the speed bleed off until a did a nice wheel landing at about 35 to 40 mph. At that point, I added power without letting the tail come down and almost instantly I was off the ground again. The next approach I added one notch flaps and crossed the fence a little less than 50 but holding a little more rpm. The speed bled off and I held it off until the airspeed dropped to just below 35 and it settled on all three wheels for a short rollout. The new spring shocks worked great in softening the touchdown with no bounce at all. I thought it was my landing skill but James assured me it was the new gear.

Conclusion: The Superlite is a great little airplane especially with the F-23 in the nose. If you are looking for a safe reliable plane that is a blast to fly, give James a call. And for all the Kit Fox Lite flyers out there, be thankful James picked this plane up and put it back in production. Any part you might need for your plane just became available plus many upgrades.

Terry Alley
Kit Fox Lite
N3169

Saturday, September 5, 2009

Photos of our first production aircraft

I just posted photos of our first production FAR part 103 aircraft on flickr.

You can find them here:

http://www.flickr.com/photos/beliteaircraft/

Have a look and tell me what you think!

The cowling is not yet installed on this airplane.

Thanks!

James

Sunday, August 30, 2009

Sport Pilot Cover Story on Belite Aircraft; New Pricing

I am, in my heart, an entrepreneur. I like to take risks, innovate, market my ideas and see what happens.

At Airventure, I was privileged to introduce a new aircraft: the Belite 254 CF, which is a FAR part 103 legal airplane. This aircraft features a lot of carbon fiber, in a very delightful, small package.

This airplane caught the attention of a lot of people.

We had chosen to display it in the North exhibit area, far away from the rest of the ultralights. We chose to do this because we felt we had a fundamentally different idea about how an ultralight should be designed and marketed. We thought our potential customers might not be ‘ultralight’ enthusiasts. We were looking for people who appreciated innovative engineering, sprightly design, good looks, and a measure of taildragger conventionality, all while flying and owning an airplane that does not require an FAA registration, nor a pilot’s license, nor a medical. (Bad or declined medicals are welcome as well, thanks to the graces of Federal Aviation Regulations FAR part 103.)

Our friends at the Experimental Aircraft Association have chosen to publish an article about the Belite as their cover story this month (September cover) in Sport Pilot magazine. We are truly honored.

We have decided to streamline our product offering a bit. We created a new low cost version of our airplane, which we call the Belite 254. It looks exactly like its big brother, the Belite 254 CF, with the exception that the rear fuselage is not fabric covered. Have a look:

We were able to cut the price by using more aluminum and less carbon fiber, and by cutting out all of the options which add expense but provide no benefits to the patch flyer. As a result, it is available ready to fly for $25,000 less than the Carbon Fiber version!

Here's another pic (the windshield hasn't been installed yet, but will be later this week.)

We will be introducing a cost reduced *kit* as well, which will be available for substantially less. This is possible because we are paying careful attention to the options which people want, and we are also able to cut out some labor expense by tack welding the steel. Many of our potential customers want to do their own welding; we're happy to oblige. This revised kit pricing will be announced in September, and it will be big, welcome news for budget minded homebuilders! Stay tuned. (Send an email to us: info AT beliteaircraft.com, if you are interested in our kit pricing when it’s released.)

Here’s our new price list:

1) Belite 254, Ready To Fly, for $29,995. This plane incorporates a lot of goodies: Carbon fiber firewall; 28HP engine; full span flaperons; aircraft grade steel fuselage and cabin; 5 gallon detachable fuel tank; (for easy refueling); 5 inch wheels; brakes; electric start, full lexan windshield, fiberglass cowling, flight instrumentation, much more! Also includes a sharp looking paint job! We believe that this is the finest value in very light aircraft in the world. It looks like an airplane, it flies like an airplane, it’s economical, and the wings fold for easy storage and transport. It crushes FAR Part 103 weight requirements with a flying weight of about 235 pounds!!

2) Belite 254 CF; Ready To Fly, for $54,995. This version adds approximately 50 features, including carbon fiber spars and ribs; hydraulic brakes; wood instrument panel with lots of good stuff in it; ballistic parachute; the list goes on and on. You name it, the Belite 254 CF has got it as a feature.

3) Belite 254 KIT, price to be announced in September! Stay tuned.

Now the fine print bad news: Our delivery position availability is limited. A deposit of $2,500 holds a delivery position. First come, first serve. We reserve the right to raise prices at any time. Etc., Etc.

Specific details of each configuration are in the website, www.beliteaircraft.com

If you want to see it fly, look at http://www.youtube.com/user/BeliteAircraft#play/uploads/0/byy6qR8TB5w to see our demo video.

If you are looking for the very finest Part 103 legal aircraft, you have arrived. Enjoy!

Fly Safe and Have Fun,

James Wiebe, CEO

Belite Aircraft

P.S. We are looking for qualified dealers and international distributors for our aircraft. If interested, please understand that we require dealers to order a demo unit (to show) and one more aircraft. We have a similar program for international distributors. In return, we offer a generous discount and a territory.

Sunday, August 9, 2009

Breaking a Carbon Fiber Wing!

EDITOR'S NOTE, added NOVEMBER 4, 2010:

1)  The stated load of about 1100 pounds, is loaded onto one wing in this test.  Multiply by 2 for the total load that the wing structure would 'see'.  It has come to my attention that this lack of clarity has confused some people.  Sorry!  1134*2 = 2268.  2268 / 4 = 567 pounds.

2)  We are now using an improved carbon fiber spar --  more carbon fiber than the one tested below.  We now have our spars made for us by Forte Carbon.

Original Post:

We received requests before and during Airventure to show actual G testing of our Carbon Fiber wing. I'd promised one person to post some photos shortly after Airventure. While I had performed testing on individual spars, I'd yet to test a wing as a completed assembly. So yes, I was working in the theoretical, and it was time to 'show me', as our friends in Missouri would say.

The timeline to do all of this was significantly accelerated by the fact that both wings took damage in transit to Oshkosh on the truck. To add insult to injury, we managed to pierce the fabric of one wing with a prop blade on the way home, and then bent the rear trailing edge beyond the point of easy repair. In other words, the wings were now ideal candidates for further destructive load testing, rather than repair and reuse.

As background, carbon fiber does not behave like any metal. Whereas metal, when highly stressed, will begin to deform yet still provide strength, carbon fiber will take loads nearly to 100% of strength without permanent deformation. Therefore, the testing of a carbon fiber structure provides a different set of insights into the construction and engineering of the wing than does an aluminum spar. Unfortunately, the test regulations cloud the issue a little, but then again, we're part 103, so those regulations don't apply to us.

Carbon Fiber has the nasty habit of shattering when it hits the load limit. We do our testing with an air of caution. We don't want to be under the wing when it breaks, nor do we want to catch splinters from the destructive force of all that tension as the wing shatters into piles of useless jaggies.

We wanted to demonstrate that our carbon fiber wing statically exceeded our stated spec of 3.8/1.5 Gs. I had mentioned to some that I thought the wing would sail past the requirements without difficulty. FWIW, if you're paying a premium for Carbon Fiber, it's nice to know that it's both lighter and stronger.

I was a little intimidated by the idea of flipping the airplane upside down to measure. So we started with the easy test: a negative G test.

This simply involves piling loads of weights on the top of the wing. The most significant thing this demonstrates is that the lift and jury strut assembly is up to the task of holding the weight.

So, without further ado, here's a pic of our Belite 254 holding 2G worth of weight off the ground. This is a negative G test.


You can see that we removed the wheels from the plane prior to the test.

I had a good look at the Carbon Fiber lift struts in our part 103 airplane. While it's hard to say in this kind of test, they didn't appear to be too stressed. (If they fail in this compressive load, it's fair to say that the disintegration would by quick and dramatic, as the entire load on the wing would tumble to floor.)

Now, on to the test that really concerned me -- the positive G load test.

We attached our wings to another fuselage, which was flipped over and held off the floor on the bolt attach points using concrete blocks.

We proceeded to lay foam over the wing, and then we started to pile the weight on.

When we hit close to 3Gs of weight, one of my employees began to have that stunned look on his face, as if we were demonstrating an impossibility. I knew that aerobatic airplanes went to +9 or even higher demonstrated G loads in their wings, and I mentioned that to him. He still looked stunned.

Now the first piece of bad news.

As we came close to 3Gs of positive load, the wing made a few popping sounds, but did not collapse. My employees thought I'd call off the test, but that's just not the way I do things. We
continued to load weight on, and the wing continued to make popping sounds. Then I realized what was happening: the individual ribs were failing under compressive loads coming through the fabric, but the spars were holding fine. We pulled the weights off, and the bottom of the wing showed crush damage into the wing. I cut the fabric open, and sure enough: the ribs had failed.

Well, I'd rather have it happen now than after delivery to a customer.

Several ribs showed crush damage, with the failure mode essentially being delamination of ribs under compressive load. (The load vector was from the bottom of the rib, through to the top of the rib.) Instantly the gears turned in my head: I needed to add some strength from the top to the bottom, which would always be in compression, never in tension. That characteristic immediately made me think of the use of plywood stiffeners, not carbon fiber.

A few days later, another wing panel was ready to test, with a slightly revised rib design. (The addition of the rib stiffeners added about 10 ounces of weight to each wing, while increasing the crush characteristics of the rib probably by a factor of 3x+...)

Weight remains critical to everything we do. This new set of carbon fiber wing panels were coming in very light in weight (we're getting better and more uniform), so we really didn't change our net weight on the wing. A quick run on the scales, and the numbers were confirmed: the weight of the wing panel was well under 14 pounds, even with the improved, heavier rib. Less than 14 Pounds!

Caveat: This wing panel wasn't yet covered (and covering adds strength) but I was eager to give the positive G loading another test. So the sawhorses were set up to catch the weight at the fuselage strut attach points, and at the spar attach points, exactly like attachment to the airplane fuselage and struts. The lift vectors would resolve differently (in flight, the main spar would be in compression, and this vector was not in our test; likewise, we didn't use lift struts, and they would be in tension through the strut attach points).

A few minutes later, the wing panel had a load of a little over 1100 pounds on it. 4Gs! So Cool!

I grabbed the camera and started to position myself to take a few shots.

And then it happened: a loud pop, and the wing visibly settled downward. I knew immediately that one of the spars had snapped in two.

EXCEPT I WAS WRONG!

One of the sawhorses had failed, causing the popping sound. The wing was fine, unbroken.

The wing was now suspended on the other good sawhorses, and on the remainder of the broken sawhorse, and on a 'safety' post which had been under the end of the wing just for such a situation.

In other words, the failure of the sawhorse caused the load to instantaneously shift from the design configuration, to some other configuration, and nothing in the wing was broken, even as the 4G load shifted around the wing. It was sort of like a lift strut failed in flight.

Very. Impressive.

I could see that an additional further failure of the broken sawhorse would be a catastrophic problem. I quickly unloaded 1100 pounds of sand from the wing without even taking a photo.

I rearranged the sawhorses, and made a couple of wood cross bars to spread the load from the wings to the sawhorses. Newly confident that the sawhorse configuration would now hold, the wing was loaded up again to 1134 pounds. Would our little wing, our very high technology carbon fiber, be up to the task for our part 103 ultralight?

I knew it would be.

Here's a photo of the resulting 4G load.



Facts:

1. The wing panel weighs less than 14 pounds.
2. The weight under test is about 1134 pounds.
3. Deflection at the tip was 2.5 inches. (Would not include deflection due to lift strut stretching under tension, if any).
4. The first 5 rib positions have 200 pounds each. The sixth has 100 pounds. The seventh position, or wingtip has 20 pounds. The weight of the wing is just under 14 pounds. There is a clamp on the rear of the wing which weighs a pound or two. Total weight: 1134 pounds.

Opinion:

1. With covering, this wing design will hit an ultimate load of 5+Gs. How much, exactly, I don't know. But based on the deflection, and the characteristics of carbon fiber, someone smarter than I should be able to offer a guess.

Our stated strength is +3.8/-1.5Gs. We do not approve aerobatic maneuvers. :-)

Sunday evening: I've decided to add a bonus photo of the original test which failed the ribs.


In this earlier positive G loading test, the weight is 14*32.4 pounds + 6*50 pounds per wing for a total of about 1530 pounds across both wings, and as can be seen, the test was done with the fuselage inverted. As a result, all loads are resolved as if the wings were really being stressed in flight. We continued to load a few more bricks on the wing before we stopped the test, due to rib failures.

Monday, July 27, 2009

Oshkosh / Airventure and Belite, Day 1


It's the end of the first day of Oshkosh. I'm the only one in our group of five who's still up. I just got done creating a 38 slide .ppt document for my presentation tomorrow, "How to reduce weight in ultralight aircraft". It covers 4 major areas: engines, carbon fiber wings, wheels & brakes, and miscellaneous things like our fuel tank design. All in all, it explains step by step how we cut over 50 pounds out of the weight of our aircraft design. Cool! By using a different (lower HP) engine, we could have cut 80+ pounds. Very cool!!

In hindsight, it appears that it would have been possible to fly our bird with a weight of less than 210 pounds. We could have done it, but we focused on improving it and using our weight budget wisely.

Pricing: We're offering the airplane at the show with a free engine and free wing assembly, so you can end up with a 'bolt together' kit that includes just about everything except paint and propeller, all for $25K. This would be for what we call the 'classic' kit, which uses wood and aluminum in the wing. The Carbon Fiber option costs $7K more. We'll build and cover it for you for $19K more; We'll upgrade the engine to 45HP for just $1K more. Lots of bargains, just at Oshkosh.

I heard some great comments today about our airplane -- many thanks! Here's what attracts people's attention:

1) The overall design.
2) The fact that it can be flown with no medical, or even a busted medical.
3) The visibility -- the rear window design.
4) The fishing rod compartment.
5) The lightweight engines.
6) Of course, people love the Carbon Fiber.
7) No FAA registration.
8) No pilot license. (We do strongly recommend tailwheel proficiency,... )
9) Very quick building. About the fastest build possible.
10) The steel fuselage (even though it only weighs about 42 pounds.) Because it's crashworthy!
11) The quick performance with the big engine.
12) Really meeting part 103's weight requirement!

There's a few other features that I haven't spoken about much. We have carpet in our plane, and the fuel tank is quick disconnect, so you can refuel it outside of the plane. The battery is quick clip removable as well, so you can start the engine, and remove the battery, should you desire. This can save weight, too.

I now have a new email address as well: james AT beliteaircraft DOT com.

I'm also pleased to report that it looks like we are getting some significant media coverage: I'm expecting a great article on the airplane, and I did two great interviews today as well.

The picture I posted at the top of this post is from our photo shoot, a few weeks ago at Jabara.

We repainted the cowl just before we left for Airventure, it looks fantastic. I'll try and get pictures posted tomorrow.

See you tomorrow,

James

Thursday, July 23, 2009

Blue Highways; Flint Hills


“Blue Highways; Flint Hills”


(c) 2009 by James Wiebe; all material and photos are copyright. Please link to this blog and to www.beliteaircraft.com


1. 20 Miles.

I can see for up to 20 miles, depending on which way I look. Looking south, an expanse of prairie grass heads downslope, along my impromptu runway, to a line of trees which look to follow a creek. For my miles beyond that, the terrain slowly rises and eventually disappears in a flint hills ridgeline.

To my east, far in the distance, are what appear to be cell phone towers. They are perhaps four miles away, at the top of a ridgeline. I can also see continuous green pasture between me and the cell towers. The landscape is typical of the flint hills. It is beautiful, and alive. I hear the constant buzzing of insects. Earlier, after my airplane came to rest, a group of cows stared at me. They wondered if I had brought Alfalfa pellets. No, I hadn’t, and they wandered off.

Just a couple of hundred yards to the north, the land forms a grassy knoll and then the terrain disappears behind the back side of the knoll. The cows went that way.

The terrain to my west is grass, with a road far off in the distance. I see a car on the road; it is visible because it is traveling rapidly and raising a ball of dust. Later, I will decide to hike towards that road.

I have a Garmin GPS, which is very helpful. It tells me that five miles away, is the Kansas State Turnpike, I-35. To my south, about 1.5 miles away, is county road 50. A line of trees that I mentioned in that direction, and I’m not sure if the road is before or after the trees. Is that creek over there as well? I have no idea, and the GPS doesn’t offer that clue.

Now I am attempting a hike northeast, towards county road 70 on the GPS. I can’t get to the road; I am stopped by another creek. The creek was slightly flooding as a result of heavy rains a day or two ago. I could have crossed it, but it would have meant soaking my ankles. I see a tree which has fallen perfectly across the creek. Considering giving it a try; but NO, I don’t want to risk soaking myself, my Nikon D300 camera, my GPS. So I head back to the airplane.

I am in the middle of the flint hills. I am sitting on the wheel of my airplane. It is sitting at an odd angle, with the left wingtip 6 feet above the ground, and the right wingtip one foot above the ground. I’ve pulled the seat pad out of the airplane, and I’m using it to keep some cushion between me, the wheel, and the grass.

There are no roads here. There is no airport. I am here. My airplane is with me, sitting, wounded.



2.
Formation flying.

The day started with last minute details for a flight to Airventure, Oshkosh, Wisconsin. We wanted to fly our demonstrator airplane up, as a promotion for our new aircraft and our new company, Belite Aircraft.

My friend Terry Alley and my coworker Gene Stratton had been working with me at Jabara airport (KAAO) to make some last minute tune-ups to the bird. We’d installed a rudder trim tab because of nagging right foot pressure, and that had solved a problem. The plane had been loaded. The electrical system on the plane was acting up, probably due to a bad voltage regulator. In a fit of disgust, I had disconnected the voltage regulator. Electric operation is not a necessity in an ultralight.

Our demonstrator airplane was flying nicely.

Terry and I took off in a formation flight towards Emporia. It was an extraordinarily beautiful morning! Blue skies. Occasional radio calls. A little maneuvering for photographs on the part of Terry. As we reached Cassoday, KS, I no longer hear from him, and decide that he has headed back home. He’d told me he’d break off there.

The plane is remarkable, and has a gas gauge which shows my fuel quantity. It showed a full tank at the start of the flight. I had ‘tankered’ an additional 2 gallons of fuel so I could land and refuel anywhere, if necessary. (FAR 103 regulations prohibit a tank capacity of more than 5 gallons).

My fuel gauge hung on full for a while, then started to descend a little too quickly through ¾, ½, and down to ¼ tank. Over the flint hills, there are few options for roads, but many options for pastures. Even though only 8 miles short of the Emporia airport, I determined that the smartest thing to do would be to make a landing, refuel, and finish the leg. (Why was the fuel consumption so high? Probably an incorrectly set carb. We’ll figure that out after Oshkosh.)

I decided that instead of staggering into my Emporia on fumes, I’d make a precautionary landing and resolve the issue.

You are probably thinking that the airplane broke on landing, because of a rock or cow turd. Not so… the landing was silky smooth; the plane floated onto the field of grass as if I had edged onto a down pillow. It was smooth.


3. Landed on the prairie.

I’m grinning. I don’t even shut the engine down; it idles smoothly as I refuel the plane.

After adding two gallons of fuel from my spare tank, I tried to take off.

Trouble; I can’t get enough airspeed. The grass is a little high and I may have a touch of tailwind. I try to takeoff twice; it doesn’t get airborne. However, I’ve got several degrees of downslope on the hill, and I can taxi up the hill for a long ways; no problem! I can resolve the takeoff speed issue.

Turning around, I headed up the hill. As I approached the spot to turn around and try again, my right main gear axle sheared off. In a quarter second:

The right landing gear collapsed as the tip of the steel, now without a wheel, punched into the dirt, and bit hard.

The propeller disintegrated. All three blades snapped off.


Dirt was thrown on the plane as the propeller augured through the ground.

The engine quit, now.

The right wingtip of the plane hit the ground, bending a clip.


“Well, that’s that”, or something to that effect went through my head.

Stunned.

Unhurt.

Bewildered.

The plane is completely undamaged, except for the prop, the right gear (it looks like a pretzel), the bent clip and unknown engine damage, if any. There is absolutely no damage to the fuselage. The gear attachment points are unharmed.

Already considering what’s and why’s.


4. Cellphone service.

I pull out my cell phone and call my wife. Over towards the northeast, I can see the cell phone tower which is almost certainly carrying the signal to my wife. The connection quality is perfect.

I’m bright and cheery as I talk to her. She asks if I'm at Emporia. No... I carefully explain the sequence of events. She is not angry, (for instance: why did I try and take this trip in an ultralight?!) but seems just pleased that all has ended well. She and I begin to strategize about how to get the plane back to Wichita, so it can be trucked to Oshkosh. We agree to leave the retrieval task to our able helper Gene Stratton, also my friend Terry Alley.

A weird thing happens. A few moments later, my cellphone rings. I look at the caller ID, and it is someone calling from CRU-WiebeTech, my old company. She is of course completely unaware of my circumstances. She has a marketing question. I answer it, I consider telling her what has happened, I think better of it. I say nothing about my where and why I am.

4 hours pass.

I took a hike. I got sweaty. I rue my decision to not pack any more water in the airplane. I had one diet Dr Pepper, and it is long gone.

My daughter calls me (my cell phone service continues to be perfect.)

To quote Bill Curtis, “I found the internet!”. My USB dongle and my laptop computer works great, and I get caught up on my personal email for the first time in a while. I send an email to Don Hackett, at Wichita State University, hinting that I am in the middle of the Flint Hills with a big story to tell. He emails me back, saying he can’t wait to read it, that it will certainly entertain my grandchildren some day.

Since I am back at the airplane, I work on the computer while I am sitting either on the airplane tire (the good one, not the snapped one) or by sitting on a cushion on the ground. I consider that if I had to spend the night, I could do so, as I brought a sleeping bag. But I do not consider the ticks. Hours later, when I was safely back home, I look at my ankles and see that they are covered with small ticks. Dozens of ticks; even smaller than a pinhead.

I’m told by my wife that Gene and Terry are coming, also my daughter, Jennifer. If they can get in the pasture, we’ll have no problem dismantling the wings and loading the plane on a trailer.

There they are, driving across a sea of green grass.

Please hand me a bottle of water.


5. Those last two italicized lines were a fantasy.

Gene, Terry and Jennifer are not here yet. It is late afternoon, and I am very thirsty. My cellphone continues to work great. Kathy and I continue conversations on marketing and logistic issues related to the upcoming Airventure show.

Jennifer calls and texts me, they are very close to me. I have picked a flint hills pasture which is several square miles in size. They have found a locked gate. They want to know if they should find someone with a key first, or hop the fence and bring me water and food. I ask them to hop the fence. I think they are about a mile east of me; if I walk towards them, and they walk towards me, we’ll meet, right?!

I’m eager for the water. I stupidly leave my cap and GPS at the airplane, but I do take my cellphone. I start hiking east. My wife calls again, and I explain what we are trying to do.

About 20 minutes later, I see two dots far away. One is wearing a bright orange shirt – that’s got to be a Belite T-shirt, which is one of our corporate colors. The other is my daughter. I call Gene. He can’t see me, but I can see him plainly. I tell him to turn left 45 degrees and walk towards the sun. He proceeds to do so, then his image dot disappears as he descends into a gully. I also descend into another gully. 15 minutes later, we are both out of our respective gullys, and finally in sight of each other.

When we finally meet, he and Jennifer are on one side of a barbed wire fence, I am on the other. He hands me a bottle of water. It is gone inside me immediately. He hands me a Diet Dr Pepper, which is still cold, and a cheeseburger.


6. What does an Angel look like?

We have to figure out how to get the trucks and trailer from the locked gate, across a pasture, a mile to the East, over to the barbed wire fence, through the fence, to the downed aircraft, a mile or more behind me.

My friend Terry remained at the locked gate, then went looking for someone with a key.

While all of this is being considered, Gene spots a pickup truck driving slowly across the flint hills, inside the pasture which contains my airplane! He hands me his hiking pack, and takes off quickly towards the truck.

Jennifer and I walk at a more leisurely pace towards the truck.

Gene catches the truck, when Jennifer and I arrive a few minutes later, Gene is sitting in the cab with our Angel. His name is Calvin, he works for the landowner, and he is here to feed the cattle. He was unaware that a broken airplane is in his ranchland. He is eager to help.

Calvin helps us – taking us through a gate in the barbed wire fence, then to the locked gate beyond the next pasture. He reaches in his glove compartment, pulls out a key, and a moment later the gate is open. Our aircraft trailer is sitting there (it’s actually Terry’s) but Terry’s truck is gone. We can’t get him on the cellphone. He’s out looking for a key; but we already have the gate unlocked. Gene and Calvin drive off, looking for Terry. Jennifer and I get in the company pickup truck, which we turn on and crank up the AC. We talk. We smile. Jennifer is so glad to see me.

Eventually everyone returns. Terry has found some other people, who were trying to get ahold of Calvin. (We already found Calvin.) We all head back towards the downed aircraft. There are three pickup trucks and one aircraft trailer heading across a cattle road in the flint hills. Calvin knows the pasture extremely well. He tells us they recently had heavy rain; he keeps us from heading down gullys.

Soon the work begins on dismantling the aircraft.


7. The cattle watched, and a plane went back to Wichita.

The landowner and his wife show up. Another lady shows up. A child is along with the couple, cheerfully tossing alfalfa pellets from the back of yet another pickup truck to the cattle, who have also showed up. There are a great many cows, all milling around the pickup trucks, the airplane, and the people.

There isn’t a great deal of work involved with disassembling this airplane. The wings unbolt, the flaperon cables unclip, the flaperons also unbolt. In about an hour and a half, the airplane changes from wounded to disassembled and stored on the trailer and one of the pickup trucks.


3 hours later, we are back in Wichita, at our workshop.


8. Grateful.

I had the opportunity to muse on things which I am grateful for, and people rose to the top of my list. First of all, to my wife, who shares this adventure with me. To Gene, who has become more than a coworker. I value his counsel and ability to get any job done. To Terry, who quickly has become a great friend. And of course, my daughters, who are intelligent and loving. Thank you Jennifer, for your insistence on being part of the rescue squad.

I am especially grateful to Calvin and the others who helped us get the plane out of their grazing land. Thank you! I’m sorry I didn’t get all your names. Your cheerfulness and desire to help made an indelible, wonderful impression on me. I was worried that I had landed in your pasture. You were simply pleased that I wasn’t hurt.

Finally, I am grateful to God, whom I believe in. The gear was destined to fatigue and shear off, sooner or later. It could have happened while landing on concrete, or it could have happened while taxing around in the flint hills. My demonstrator plane will be at Oshkosh, hardly the worse for wear, but it’s not flyable until the engine is torn down. The shaft still turns freely, but there clearly is a raspy feel to it. Cracked bearing? Bent crank? We’ll see. Also, we'll redesign the wheel axle shaft immediately to improve strength.


9. Final thoughts?

Whose fault was this? I’ll stop the debate right now – it’s entirely mine. Inadequate fuel planning; perhaps improper carb setup; inappropriate landing location. The plane handled the situation with sweetness amidst difficulty.

I WILL NEVER FORGET THE FEELING OF SITTING IN THE AIRPLANE, SUCCESSFUL, AFTER SOFT UPHILL LANDING, WITH ENGINE IDLING, ON THE FLINT HILLS PRAIRIE, SOAKING IN TO ME...

William Least Heat Moon writes of Blue Highways. This was mine.

--- James Wiebe, written somewhere in the flint hills near Olpe, Kansas, and completed the following day. Wednesday, July 22, 2009, and Thursday, July 23, 2009.

Thursday, July 16, 2009

The weight of a Belite 254

If you were around our workshop on a daily basis, would see that we are constantly weighing things. We are passionate about reducing weight, staying legal, and increasing utility in the design of our Belite 254 Carbon Fiber ultralight aircraft.

I weighed the Belite 254 demonstrator aircraft on certified aircraft scales today. This particular aircraft is loaded with options. It came in at 255 pounds, without fuel tank. Because the limit is 254 pounds (actually, 253.99999 pounds) this would seem to be a failure. (I mistakenly first weighed it with the fuel tank and with fuel, and it was way over... ooops.... take out the fuel tank and reweigh...)

Our fuel tank weighs about 3 pounds dry, so today's final weight was 258 pounds. Consequently, we were 4 pounds overweight relative to FAR 103. I'll explain how we solved the problem in a few moments.

Here's what's on the airplane:

1) 4130 Steel airframe / elevator / rudder
2) Covering system with UV protectant
3) Bungee landing gear
4) Grove gear
5) Grove hydraulic brakes
6) Enlarged tail wheel
7) Rudder steering
8) 45HP engine, derated to accommodate part 103 cruise speed (with more work to be done)
9) 3 blade Powerfin prop
10) 5 gallon fuel tank
11) Electric Fuel gauge
12) Airspeed indicator
13) Altimeter
14) Tachometer / Hourmeter
15) EGT / CHT
16) Voltmeter
17) Turn & Bank
18) Instrument panel, made of wood
19) Transceiver and permanent antenna
20) Transponder and antenna
21) LIPO Battery System with current system
22) Engine Starter Relay (but no electric start with this current engine)
23) Voltage regulator for radio
24) Alternator (this airplane generates electricity to run avionics and charge the battery)
25) Gizmo Dock

I'm sure I'm forgetting something. It's loaded with goodies. The panel would be comfortable and pleasing to any VFR pilot.

My goal was to have a FAR 103 airplane with high technology construction (Carbon Fiber), amazing power, full panel, etc. So now I've crammed all this stuff into the demonstrator, and I'm 4 pounds overweight.

Here's the solution:

1) We quickly reconverted the gear from bungees to solid. This saves about 28 ounces. I then removed the turtledeck, as it is not necessary for flight. Another 22 ounces saved. Finally, I removed a chunk of aluminum which was simply not necessary. (We'd been using it as a base for fuel tank in the baggage compartment; no longer necessary.) It also weighed 22 ounces. Total savings: 72 ounces, exactly 4.5 pounds.

Final weight, as adjusted: 253.5 pounds. FAR 103 legal! Loaded with features, engine, and performance! It can be done. (If configured with a smaller engine, performance remains VERY SIMILAR and weight drops further -- the 28HP engine weighs 18 pounds less!!)

I've heard reports of guys breaking their bungees and consequently hitting the props/destroying the engines. I'm OK without bungees for awhile. We'll figure out something to add them back to the demonstrator sometime soon.

The demonstrator still has a little work to do in Wichita, but it will soon be ready to move to Oshkosh. For example, Friday morning, we're doing an air to air photo shoot.