The 1/4 scale radio control model and wind tunnel model is making progress. The cnc (computer numerically controlled) machining has been accomplished, and the body, tail and wing shapes are ready for the prep work to make molds. Once the molds are made, parts will be manufactured from them for the fiberglass panels that make up the body, tail and wing. (Main wings are shown at right).
 

We opted for cnc machining because it gives us a very accurate reproduction of the shapes involved. Some calculations will need to be applied to the wind tunnel results to correct them for effects (since the model is not full scale, this influences the results, and that is corrected for with math equations).
 

These equations will be done immediately after the wind tunnel work. Below are shown the vertical tail pieces and horizontal tail pieces. At the bottom of the image you can see the horizontal tail cross-sections shown where they intersect the larger verticals.
 

Our funding has opened up, and we are moving ahead faster now. I anticipate more funding potentials closing soon, and that will only mean more progress to report to you on upcoming Progress Pages!

-The Samson Team

The wood ribbing in the images above show the size of the vehicle body in relation to the wheels, steering, etc. For those who want to build an RC model for yourselves, please email in your preference on cockpit glazing, as it is more expensive to do clear glazing than have a painted cockpit window. Do you want the RC model kit to have clear glazing for more realistic look at a higher price, or provide it as cheaply as we can by using a painted windscreen? Email to: sbousfield@samsonsky.com

We are beginning to build the relationships with several universities that would enable graduate students to participate in some of the advanced work, and may also involve wind tunnel testing of the 1/4 scale model.

On the full-scale prototype, the propeller design has been accomplished as part of the ducted fan design. The propeller has some unique features and blade configuration (mostly angle of attack), dictated by the speed of airflow through the duct.

It is based on the Warp Drive propeller mounting system, at least for the prototype. We have talked with other propeller companies, and the final propeller is still under consideration. With the fixed pitch propeller for the prototype, we will be using the wheels powered at take-off to assist in getting up to speed quickly. This allows the prop to be designed more for cruise and climb, while still improving take-off performance. The wheels will be disconnected during flight, as it would be a waste of energy to have them spun during flight with little or no benefit.

-The Samson Team

In the case of our duct, we have increased static thrust (good for take-off) and decreased noise (good for neighborhood relations). This came at the expense of 4-5% hit on cruise performance in relation to what we could get from the same size free- propeller.

The diagram below is a horizontal cross section through the ducted fan area of the vehicle. You can see how the duct is being altered with a larger radius on the inlet (1), and also a larger radius at the intersection of the body to the prop hub area (2). We are also showing a pusher hub (5) that we will use to gain a bit of extra thrust off the pressure recovery (slowing down the airflow creates high pressure areas on the back side of the hub (4) pushing us forward). It is amazing how little details can make such a difference.

Some really big names have joined Samson’s executive team, from the top ranks of American auto and aviation industries. Some you may have heard of, and some are known more by their amazing achievements. This is a tremendous vote of confidence for us, and their participation in the program will be a huge boost to Samson. When our funding is completed, and we have launched that portion of the business, we will be announcing these teammates with the fan-fare they deserve.

We have also upgraded the website with new images showing the ducts for the radiators, which are located just behind the additional side windows. This arrangement takes the turbulent air created by the windows and pulls it through the radiator. This should reduce the drag from both. The new side windows were included to increase visibility. A ‘moon roof’ will be analyzed structurally to further improve visibility if possible. Though we may look like a Ferrari, we are designing this vehicle to be a useful and safe aircraft as well. On the Models Page / Switchblade, there is a new 360 degree view feature available.

Also available now on the website is an option to download wallpapers and screen-savers of your favorite Switchblade images for your computer, iPad, or phone. They come in different sizes, and some have a series of images that will rotate through automatically. These are accessed from the Images Page at the top righthttp://www.samsonmotorworks.com/gallery. Now your computer can be decorated with real ‘conversation-starting’ images!

No matter how much or little you fly, the future is waiting for you. That future is in the air, and your adventure is coming soon. Perhaps not tomorrow, but it will come.

Best, Sam Bousfield
CEO Samson Aircraft, Inc.

The systems run an electrical current through a small tank of water to produce hydrogen gas while the engine is running (so you don’t have to worry about storing hydrogen safely). This small amount of hydrogen is fed into the engine to work as a catalyst during the combustion cycle to increase efficiency.
Our first test was conducted using a pyrometer (heat sensor) connected to the exhaust from an OMC wankel engine (similar to the type of engine we are developing). A Hydrogen Boost system was installed and the engine allowed to run at 2,000 rpm with minimal loading until the temperature stabilized at 1275 degrees F (above).

While the engine was still running, the Hydrogen Boost system was turned on as the only change. The engine stabilized after a few minutes with more than 150 degrees F increase in temperature (below). We predicted between 150-200 degrees change if the boost system was actually performing as expected.

What this appears to mean is that more of the fuel is being burned, increasing the exhaust temperature as a result.  The added presence of hydrogen may have contributed to some of the heat gain, but there is actually little hydrogen contributed per combustion cycle, so we do not feel that the gain can be attributed to the hydrogen by itself.  Further testing on a dynamometer (measures power), with air mass flow sensor and fuel flow sensor will give us more of a picture.

The reason we feel this is important is weight.  If we can carry fewer pounds of fuel and go just as far or farther than we could before making any changes to the system (like this Hydrogen Boost), we can make a big change not only in the cost of flying by saving fuel, but in the reduction of emissions one puts out as he travels.  Both are important, and it is nice to find something that looks like it can reduce emissions and increase gas mileage at the same time.

Regarding the Switchblade itself, ducted fan design was finished, and a small amount of tweaking in the duct is being done prior to the ¼ scale radio control model being built.  Bill Bohn of South Lake Tahoe is our experienced model builder, and he has begun with layouts, materials purchase, and has lined up the machining work needed to accurately reproduce the wing and body.  The radiator ducting will not be functional (no mini-radiator in there), and the duct will be closed off but this should still be similar to the real vehicle in the sense of drag (air resistance).

The radiators of the real vehicle should not produce any added drag.  This is due to a design which uses the radiator exhaust to provide a small bit of thrust (like a P-51) to overcome the drag of a radiator.  Steering is not likely to be functional on our scale model.  We are setting up the model, however, to allow us to change wing angle of attack and tail angle of attack, as you would a wind tunnel model, and may actually run it through a wind tunnel prior to flight.

We are nearly finished with the design of the ducted fan. DAR Corp did a great job using CFD (Computational Fluid Dynamics) to generate a more workable shape for the ducted fan area. We are honing this with some proprietary methods to reduce the effects of negative pressure zones. Much of the negative pressure in the duct is used similarly to jet engines to provide thrust by pulling forward. The negative pressures facing aft work against that and we decided to come up with ways to mitigate these effects. We are analyzing the results for a future patent and will be able to disclose more about this shortly.

A test block was created to test a new ignition system related to Wankel engines. These rotary engines, similar to Mazda’s RX-7, provide light weight, compact power but have not received nearly the engineering development that piston engines have. As most in the industry would agree, the major areas that need improvement in wankel engines are gas mileage and emissions. Our tests and technology are aimed at improving both.

While the Hayabusa and other existing engines can adequately power the Switchblade, our future plans include a certified aviation engine capable of ground and air use. By having an engine of our own, we would be able to expand Switchblade sales and production, as well as provide an engine for our future ground-only version. There are other applications for this engine, such as portable generators, electric vehicle range extenders, auxiliary power units for aircraft and trucks, and marine generators or power units.

Our intent at Samson is to professionally handle areas related to the Switchblade and future expansion, including increasing the existing airport base, the training of new pilots and advancing the engine choices available.

The purpose of the ground-only vehicle is to give a combination of performance and mileage that is unsurpassed in transportation vehicles today, or tomorrow, for that matter.  Making transportation fun, exciting, and yet less expensive and less of an impact on the environment is a hallmark of Samson.

Starting with the suspension and drive train taken from the Switchblade, but shortening the wheelbase (we don’t need to store wings under this vehicle), we were able to come up with a configuration that allowed near perfect balancing of weight for the vehicle mission.

The engine is placed low, almost directly over the rear wheels.  This keeps the center of gravity (cg) low and to the rear for better turning characteristics.  The tires are shown white for clarity sake only.  We are expecting fuel mileage on the order of 60 mpg while maintaining Porsche performance levels.  For those who want a little extra, we may be able to introduce a high-performance version at the expense of some gas mileage and cargo space.  Check out the Hartley V8 Hayabusa, for example:   http://www.h1v8.com/page/page/1562068.htm

We didn’t have a ducted fan to worry about with this model, so the design allows more visibility out the rear through a glass hatch.  There is significant room for cargo in the back, and perhaps jump seats for smaller people if regulations allow that in your area (we are still aiming for three-wheel motorcycle classification).Twin radiator inlets form cavities on each side of the vehicle, similar to the Switchblade, and exhaust out the rear panel through mesh screens beside the tail lights.  Engine access will be between the two screens.

The images show work in progress, and if you have a comment or suggestion, please feel free to use the Contact Us / General Question form to communicate it.  Please be aware that we cannot credit each individual suggestion, or may not be able to respond to each, but we do appreciate your thoughts and ideas as we go forward with the project, knowing that you are helping us give direction and features to the final vehicle.  These must be given freely, without request or expectation of compensation, so please don’t send in anything that you feel a proprietary ownership of.

We are also happy with the new front wheel, which was custom built to allow center wheel steering with a leading arm torsion bar suspension.  The center wheel steering gave us the steering comfort and responsiveness we were after as well as a lighter assembly than the motorcycle front fork assembly we had prior to this.  We were amazed, as we felt that the motorcycle suspension system would be the ultimate light-weight solution.  We may have not had the lightest motorcycle front assembly available, but the auto-based front wheel wasn’t light-weight either, so it was apples to apples.

We were getting ready to put the new vehicle through time trials at the Sacramento Raceway, both for straight line acceleration, and for the slalom test.  As reported in the newsletter, our earlier slalom test was done with 45′ spaced cones rather than 100′ spaced cones as Road and Track does.  In order to compare the Switchblade to other known vehicles, we were going to do a slalom run with the standard cone spacing.  After our first run down the ¼ mile drag strip, we found we had stripped the output shaft spline joints.  Okay – first big weak point found!  Rather than continue finding engine weak points, we are re-building the Hayabusa with a Hartley auto-conversion.  This removes the transmission, puts in a heavy-duty bottom end, and allows us to set it up with the CVT, which is the ground-transmission we feel we will offer for both the Hayabusa and rotary engine options.  We should pick up 30 more horsepower, lose a net 30 lbs of weight (including transmission change), and have a greater reliability factor.  We will still have two independent drive belts to the prop, which will now be directly off the driveshaft and will not go through a transmission.

For now, we stripped the vehicle of engine, seats, steering, cooling, electrical, and fuel tank.  To clean things up we painted the framework, and when the engine is ready, we will put it all back together and test again.  If you haven’t looked at our movies on flying the x-plane version of the Switchblade, check out:  http://www.youtube.com/watch?v=aN4swAWvdRc and if you want to, see how well the x-plane model REALLY flies by downloading the Switchblade from our website and seeing for yourself.

-The Samson Team

http://www.youtube.com/watch?v=ad7VzBtP3sY

One thing we didn’t like was the spring force.  It seemed too stiff.  We got help from Downsouth Motorsports, and came up with a compound spring system.  There are two springs on either side, one stiff and one softer.  The softer knocks out the bumps, and the stiff one soaks up the bounces (and ideally, hard landings).  Shown here are the single springs before we changed out.   I will post the double spring images shortly.  We also moved the shock mount location to the top of the spindle/hub rather than on the suspension arms.  This was to take the load off the suspension arm joints, and take them to the hub which already has ‘beef’ to the part, and can handle the loads.  In doing so we take loads off the suspension arms, which can be kept lighter.

We improved the cooling to the oil cooler and the radiator to ensure the engine was cooled adequately even though the final vehicle will have a duct for the radiator and oil cooler/evaporator coils.  We just want the vehicle to be in top operating condition for testing.

We re-did the side window area to include an opening for the radiator duct, and to move the bottom of the door window inwards so it would be able to roll down in the door.  This type of fine-tuning is what we are working through, so that we can have an accurate flight test model when we do fly.  We may not have windows that roll down for the prototype, but they will have the aerodynamic shape of the ones that do.  The image shows a ‘zebra stripe’ model, which is used to check continuity of surfaces.  I think it might give people a headache if you painted your Switchblade like this!

If you want a thrill, check out the video being added shortly.  We went to a deserted strip and chased our tail around for a while.  The vehicle behaved well, and we shot some footage to share.  It is being edited and will be posted next week.