Oshkosh Pics, once again

A few more pics from Oshkosh...  Earlier in the week, I was flying our Cub Yellow Trike.  What a blast!!  The plane is a FAR Part 103 Ultralight Aircraft.

Here is a short final onto the ultralight field:

Here's the view of the plane, with 'hover' mode engaged:

A couple of pics of the view from upstairs:

with a view looking towards the north part of the field.  Nice view!!

I'm exhausted.  Pilot briefings every morning are at 6:30am. 

At the Light Sport / Ultralight Field at Oshkosh

I was irritated that the red plane passed me, but grateful for the opportunity to take his picture.  He is seen in the above pic, turning to the right at Oshkosh.  Lots of planes in the air, all at the same time.  While waiting to take off, I snapped a series of pics.  Here they are:

A Hummel bird.

Here's a plane that I passed.  The pilot was having a good time, dropping his feet below the seat:

Here's a Legal Eagle, coming in to land.  Nice ultralights!

And a different Legal Eagle.

This guy was having a lot of fun!  Same plane that I passed.

And here's a nice shot of whole Oshkosh ultralight flying experience:

-- James

Electric Elevator Trim on Ultralight Aircraft

First a friendly reminder:  This blog has many, many posts on many different topics.  Please explore the various posts -- I've written on all kinds things -- some serious, some contemplative, some informative.  Have a look around!  Now, on today's topic:  Electric Elevator Trim Tabs on Ultralight Aircraft.

Another item on our price list which is kind of unique is our electric elevator trim.  I thought I'd show a few pictures as to how we do it.

One of the joys of flying in an ultralight aircraft (such as our FAR Part 103 Belite Aircraft) is taking photographs.  In order to do this, I like to fly 'hands free', without the plane diving or climbing.  And I like to do it at various throttle settings, which means that I need a flight variable trim system.  There's a variety of ways to do this, but here is a system which meets all of the flight trim objectives AND provides an additional redundancy of elevator control, in the event of an elevator control system failure.  Just like a real airplane...  Jumping to what it looks like when it's all done, here's the electric elevator trim and manual rudder trim, as installed on our Belite Black Dragon Superlite (YES, the paint job is spectacular...):

The rudder trim is permanently set, and when properly set eliminates any left or right rudder tendencies.  (The big engine requires a lot of right foot, without rudder trimming, so I LIKE the rudder trim.)  The elevator trim uses an electric servo (designed by Belite) and a custom designed controller circuit board (which we'll get to in a few moments.) 

Now let's back up and look at these two trim tabs in the paint shop:

Well, that's kind of a boring picture.  But it does show the general clutter around the workshop fabrication bench, as well as our big battery charger.  So let's move on to some closeups.  Here's a pic of the rudder trim, prior to placement on the rudder:

And here's a shot of the elevator trim tab, complete with hinge, servo, linkage and control horn.  (Some of which is covered by painted masking tape):

This trim tab weighs about 9 ounces, as pictured.  With cable up to the cockpit, and controller board, the entire weight is about a pound.  The big holes which are drilled on the attachment tabs are used to tie wrap this to our elevator.  Let's mount this trim tab on the elevator:

You can clearly see the black tie wraps, along with the electric cable which has been snaked around the back of the elevator.  The wires have not yet been hooked up, but the linkage is clearly visible from the servo to the control horn.

Now let's move up to the cockpit, and look at the panel:

The big red push button switch is for the electric starter relay, the two red toggle switches are magneto kill switches (left and right) for our big Hirth F23 50HP engine, the white switch is the master avionics switch, and the black toggle switch is our electric trim switch.  It is shown in the central (neutral) position.  Moving it up causes the elevator trim servo to move one direction, while moving it down causes the trim to move in the other direction.  VOILA!  Easy elevator trim.

Now let's take a sneak look behind the panel, and see what's attached to that black toggle switch:

You can see a module which is 'shrink wrapped' and attached to the toggle switch.  It contains a small circuit board which regulates power and controls power polarity from the toggle switch to the trim servo.  This entire design is a product of Belite and is available on our assembled aircraft for $200.  This includes the servo, the electric trim tab, the controller board, the wiring, all installed.

You can see the Black Dragon Superlite, complete with electric trim and several other surprises, at 2010 Oshkosh.  Please come by our booth in the North display, and we also have a booth in the south Ultralight area.

Vortex Generators and Ultralight Aircraft

Vortex Generators.

IF YOU ARE READING THIS ARTICLE, YOU MAY ALSO BE INTERESTED IN THESE OTHER ARTICLES ON VG's and STALL SPEEDS:


http://jameswiebe.blogspot.com/2010/09/even-more-info-on-stall-speed-vortex.html

http://jameswiebe.blogspot.com/2010/06/belite-coefficient-of-lift-and-stalling.html

Vortex generators are mounted on the top side of wings, and are designed to create small vortices as air passes over the wing.

As a result of these small vortices, vortex generators (Let's call them VGs, OK?)  are responsible for doing some pretty amazing things.  Concerning VGs, Wikipedia says the following:


"Vortex generators are likely to be found on the external surfaces of vehicles where flow separation is a potential problem because vortex generators delay flow separation. ^[3] On aircraft they are installed on the front third of a wing in order to maintain steady airflow over the control surfaces at the rear of the wing.^[2]boundary layer, and run in spanwise lines near the thickest part of the wing.^[1] They can be seen on the wings and vertical tails of many airliners. Vortex generators are positioned in such a way that they have an angle of attack with respect to the local airflow.^[1] They are typically rectangular or triangular, about 80% as tall as the boundary layer, and run in spanwise lines near the thickest part of the wing.^[1] They can be seen on the wings and vertical tails of many airliners. Vortex generators are positioned in such a way that they have an angle of attack with respect to the local airflow.^[1]

A vortex generator creates a tip vortex which draws energetic, rapidly-moving air from outside the slow-moving boundary layer into contact with the aircraft skin. The boundary layer normally thickens as it moves along the aircraft surface, reducing the effectiveness of trailing-edge control surfaces; vortex generators can be used to remedy this problem, among others, by "re-energizing the boundary layer".^[1][2]

The use of VGs on FAR Part 103 ultralight aircraft has been debated at least a little; I've decided to get into the debate by actually giving them a try on our Dragon Superlite.  A couple of days ago, I temporarily attached a set of VGs to the Superlite and then flew the plane.  Here's what they look like:

How did they work out?  I don't really know.  The wind was gusty aloft, so it was difficult to check out stall speed, landing characteristics, and I've reached no conclusions so far.  But I've decided to leave them on the Superlite as it heads to Oshkosh.  Come on by our North display area and take a look.

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