JB441 Concept Aircraft

Light sport aircraft development project
We are currently in the design phase of our light sport aircraft project. This aircraft is a single-place, light sport aircraft aimed at pilots wanting to own one of the most affordable but high quality kit aircraft available. Our goal is to enter the market as the lowest cost all aluminum kit aircraft available, but maintain the quality of the top expensive kit manufacturers.
Seats: One
Wingspan: 20ft 0in
Wing Area: 55 sq ft
Aspect Ratio: 7.27
Wing Loading: 10.9 lbs/sq ft
Length: 18ft 6in
Gross Weight: 600 lbs
Useable Load: 345 lbs
Fuel Capacity: 20 US gal
Engine: Kawasaki 440 or similar
Power: 38 HP
Power Loading: 15.8 lbs/HP
Cruise Speed: 105 mph
Range: Approximately 600 statute miles
Stall speed: 52 mph (landing configuration)
Three view drawing

Horizontal Stabilizer Assembly Riveted
Horizontal Stabilizer Assembly Completed. Very pleased to be posting this as well. Currently working on the elevator attach brackets and hopefully I’ll be posting pics of the completed horizontal with elevator soon.


Horizontal Stabilizer Assembly Being Clecoed
Horizontal Stabilizer Assembly Being Clecoed. Very pleased to be posting this. Glad to have progress finally!


Horizontal Stabilizer Test Fit Assembly Riveted
Completed test fit assembly.  Came in a couple ounces lighter than we expected which is good.  Now to start making the full horizontal and elevator…

Horizontal Stabilizer Test Fit Assembly Clecoed
We finally got all of the components for our test fit assembly made.  We’ve clecoed them together and are working on deburr, dimpling, and riveting.

Horizontal Stabilizer Test Fit Assembly
This is a test fit assembly. Just to make sure parts would fit, we are assembling a small span version of the horizontal stabilizer. Seems to be going together well.


Horizontal Stabilizer Test Fit Assembly
Another picture of the test fit assembly. This time, the inner structure.


CAD Model with transparent skins
The wing and horizontal tail structures are mostly finished with detail design. Here you can see the structure due to the transparent skins.


Horizontal stabilizer ribs, formed
Horizontal stabilizer ribs, formed on a forming block that we machined.


Horizontal stabilizer rib flat, formed rib, and forming block
Forming block, formed rib, and rib flat for the leading edge rib on the horizontal stabilizer.


Complete CAD Assembly – Front Upper
All major structural components are assembled and ready to be mocked up.


Complete CAD assembly – Lower Rear
All of the main structural components are complete in the assembly. This view shows the wing root fairings.


Working CAD model
This is the most recent revision to the working CAD model of the full aircraft. The horizontal stabilizer is complete with all parts shown. The wings are mostly complete, but lacking some ribs, hinges, and control mechanisms. The fuselage is loft only, but with some panel lines in place. The airplane will be all aluminum structure with composite fairings and cowlings.



Earlier concept CAD model
This is an earlier concept model with composite fuselage and aluminum wing and tail assemblies. A lot of the components are missing or have been changed since.


Wing Assembly
Wing assembly. Skins are transparent showing structure.


Wing spar
Detail of wing spar assembly. All wing spar pieces are inexpensively made from punched sheet metal or extruded angle. This removes the requirement of using a large press brake for bends. Also, the spar is made of stacked flat bar which removes the requirement for step machining the spar.


Horizontal Stabilizer
Model of the complete horizontal stabilizer assembly. There are composite tips that are absent and some of the control linkage is not present.


Rib from horizontal stabilizer
A leading edge rib for the horizontal stabilizer is shown. The rib was formed by hand. For structural test, flight test, and production parts the ribs will be formed using rubber press tooling.


Mock up of horizontal stabilizer components
This is an early mock up of horizontal stabilizer components. You can see the spar which has not been bent (will be constructed out of extruded angle and flat punched parts in future versions), the spar doubler, the leading edge and trailing edge ribs, both hand formed.