BD-5 Information Memo - No. 6

The BD-5 Aircraft Is Becoming The Most Desired Aircraft Ever Designed

If the aircraft currently available have any performance at all their initial cost and operating expenses make them absolutely prohibitive except to the very few who can pay the price. If you go to the other extreme of the low cost, two-place trainer you soon discover that they are now very low cost at all. You pay the price of two or three good size automobiles and their performance is so poor that 100 hours in any one of these aircraft is more than plenty.

You can read all the ads or articles you want that claim that a $20,000, 130 MPH, four-place can be justified as a personal aircraft that anyone can afford. Since flying began, as it became more popular after WWII, we have always wanted a truly inexpensive aircraft that is solid, maneuverable and fast. In addition to this it has to be inexpensive to operate and maintain.

The BD-5 is really the answer. It is not a dream. It is a small, compact and powerful little aircraft.

We have heard it said that it is too good to be true. The only reason it is hard to believe is that the general aviation industry catered to the corporate aircraft class and have done generally well with this type of aircraft. The personal aircraft, or sport plane, was just not in existence. The manufacturers tried to tell us it is impossible. The costs are too high, etc. The majority of us in aviation have been brainwashed by this constant cry: "It cannot be done," but anyone with a gleam in his eye to someday own his own aircraft need only go to Oshkosh, Wisconsin to the Experimental Aircraft Association Annual Fly-In. There he will see those persons who have already solved their problems of having a dream airplane by going out and building their own.

The BD-5 takes what the homebuilt movement has shown us and incorporated the latest sound aerodynamics and the cost savings in volume production, and what results is the aircraft that is too good to believe.

The BD-5, the aircraft that is too good to be true, is really here! It handles fine and is meeting all the expectations we designed into it. Anyone who sees it is more excited than ever afterwards. In nine short months we have received a substantial number of orders; a greater number than Piper Aircraft, the world's second largest manufacturer, sold of all models in the previous twelve months!

We know that there are thousands who have not yet even heard of the BD-5, who are not yet aware that the aircraft they have been wanting is now a reality. We also know there are many more who are waiting for the flight test program to be completed and the production to begin. They would like to see a BD-5 in its completed form. In just a very few more months this will be a reality. Those who have ordered a BD-5 now will find themselves the most popular kid on the block, because there will be literally hundreds wanting to see the aircraft under construction as well as in flight when it's finished.

We will be establishing an excellent dealer network throughout the country. Future customers will be able to obtain their aircraft directly from the dealer, select their optional equipment and obtain excellent guidance from our factory-trained dealers. The cost of the aircraft will obviously have to go up at this time, but even those who have bought at the introductory price will benefit from assistance available from the dealers.

We have been convinced for many years that the individual who loves aviation wanted to own a personal aircraft he can afford. The BD-5 now proves we were right and we are going to devote every bit of our effort to make this type of aircraft the best in the world.

In the next year or two we are going to see an entirely new industry in personal sport aircraft. Those who will succeed in it will be those who make an aircraft the way the individual wants one; his dream aircraft.

It will not be those who keep saying it cannot be done.

BD-5 Plans

The plans are being designed to include a number of photographs and written descriptions, completely spelling out the assembly procedures. With all materials being individually marked and this identification referred to on the plans it will be of little value for someone to study the plans without having the materials in front of them for reference.

Furthermore, the plans will be so complete and descriptive that it will not be necessary for anyone to spend a lot of time studying them in order to figure out what he is supposed to do. The plans, therefore, will only be shipped complete with the materials packages at the time of delivery.

Variable Speed Drive System

The variable speed drive system works on a well-developed principle of a single wedge-type belt running between adjustable cone shives. The bottom shives are mechanically adjusted from the cockpit so they move closer or farther apart. The upper shives connected to the drive shaft are spring-loaded, and try to bring the two cone shives together.

The principle on which the variable drive works is when the cockpit control is adjusted so that the two cones are adjusted away from each other, the wedge part moves inward towards the center of the shive. Since the belt is of fixed length the springs on the upper shives force the belt out at a longer radius on the upper unit. The end result is that the belt is turning with a small diameter at the bottom and a large diameter at the top. This means that for a given engine speed the propeller will turn slower. By adjusting the cockpit control in the other direction, the bottom shives can be brought closer together, thereby increasing its diameter and decreasing the upper shive. The speed of the propeller will then increase for the same engine speed.

The whole reason for a variable speed drive is that it will give increased performance at takeoff and at climb. Since the BD-5 has a pretty high cruising speed it must be equipped with a relatively high-pitched propeller. It must also turn at a fairly good RPM to produce the necessary thrust at cruise. With a fixed drive system the speed ratio between the engine and the propeller would be fixed. On takeoff the engine could not turn the propeller at the same speed it turns in cruise. On takeoff, therefore, the engine will not be able to turn at a very high RPM. The reduction in engine speed (which is appreciable) means that the engine just cannot turn up its full rated power.

As the aircraft gradually gains speed and starts to climb the engine speed gradually improves with the corresponding increase in power output. This problem exists in all airplanes. The faster they go, the more critical the problem. Other high performance aircraft solve the problem with adjustable or constant speed propellers. These units, however, are generally expensive to buy and costly to maintain. With the variable speed drive as incorporated on the BD-5 we solve this age-old problem in a relatively inexpensive manner.

The simplicity of the variable speed drive system as used on the BD-5, as well as the use of the highest quality materials and bearings, afford us a unit that the manufacturer is projecting an 8,000-hour life between overhauls. For a homebuilt or light aircraft this would be for the life of the aircraft!

For either the 40 HP or the 70 HP engines the performance gains are well worth the cost of the unit. Also the design has been perfected enough to where the variable speed drive system weighs only 6 lbs. more than the fixed drive system. For this reason we do recommend the variable speed drive as a beneficial option.

Testing Program

We will not delivery any aircraft until these programs have been completed. Our schedules that we have been operating with in all three areas are going well and we should complete them before production begins. If for some reason we run into an unavoidable delay, and are forced to extend our test program, we will hold delivery until we obtain satisfactory results. The first aircraft will be the same as the one thousandth aircraft, and will be of proven design.

Flight Test Program

The following is a list of items to be evaluated in the flight test program. Those marked with a red asterisk have been completed to date:

• * Ground test of engine dynamics and drive system.
• * Taxi, steering and brake test.
• * Rough field and pavement tests.
• * Nosewheel shimmy tests.
• * Engine cooling with axial fan blowers.
• * Engine cooling with tuned muffler and cooling jet pump.
• * Nosewheel liftoff speeds; flaps up and flaps down.
• * Propeller drive shaft dynamics and vibration tests.
• * Propeller drive shaft main bearings and temperature survey.
• * Variable drive system maximum torque, maximum and minimum speed variation, and declutching tests.
• * Variable drive system bearing temperature survey.
• * Propeller static thrust tests.
• * Propeller inflow airstream tests with its effects on control surfaces
• * Fuselage flow distribution tests for exhaust exit area selection.
• * Fuselage tuft flow study.
• * Wing tuft flow studies at stall conditions.
• * Wing stall tests with deep stalls to 40 degree angle of attack for tail control effectiveness.
• * Basic aircraft stability and control tests.
• Static longitudinal stability for various CG locations.
• Directional stability - power on and power off.
• Roll stability and maximum rate of roll.
• Elevator stick forces in accelerated flight.
• Takeoff distance.
• Maximum angle and maximum rate of climb.
• Maximum sea level speeds.
• Maximum cruise speeds at altitude.
• Service ceiling tests.
• Maximum dive speed tests.
• Spin tests.

New Engines Announced

With our continuous efforts to keep the cost of the airplane down, as well as to keep the empty weight down for better performance, we are now happy to announce that Kiekhaefer Aeromarine has developed two new engines. The basic 440cc engine which develops 40 HP is performing outstandingly in the BD-5 prototype. This engine will be available to all BD-5 customers at no extra cost. We will offer this 40 HP engine with the basic aircraft in place of the 32 HP engine.

The two new engines now available are a 523cc 55 HP that weighs only two lbs. more, the second new engine is a 573cc which develops 70 HP and weighs only four lbs. more than the basic engine.

This 70 HP twin is considerably lighter than the three cylinder engine we had originally planned to use. Furthermore, the savings in manifold exhaust systems in both weight and cost are further improvements.

We are offering the 55 HP twin for $290 additional cost. The 70 HP twin will be available for $430 additional cost.

This of course is the cost added to the basic cost of the aircraft and includes the appropriate drive system and propeller for the larger engines. The three cylinder 70 HP will, therefore, not be available.

For our earlier customers who have already selected the 70 HP engine as their optional and have paid $450, we will be sending to each of you a $20 refund.

The price I have indicated above will hold true for all people having placed an introductory order.

We are very please that Mr. Carl Kiekhaefer has been able to develop these fine engines, which allows us to further improve the BD-5. We are also very pleased to send refunds to those who have already ordered the 70 HP engines, because every time we can make a savings and pass it on to you, the better it will be for everyone.

Jim Bede to Visit California December 10-13

Dec. 10 & 11: Palo Alto (For final arrangements for a meeting place please contact Lee Klaus - Tel: 415-828-2070)

Dec. 12 & 13: Los Angeles International Hotel, International Airport. Seminars will be held at these locations at the following times:

Palo Alto

Friday Dec. 10 - 1, 3, 7, and 9pm

Saturday Dec. 11 - 1pm and 7pm (also on Saturday a special meeting for the BD-5 customers only will be held from 9am to 12 noon).

Los Angeles

Sunday Dec. 12 - 1pm and 7pm (BD-5 customers only 6pm to 8pm)

Monday Dec. 13 - 1pm and 7pm

Canadian License

We are just finalizing a design on a new wing which would have the same span as the BD-5B, but instead of a tapered section would have a rectangular planform. This would increase the wing area and permit the gross weight to increase to 600 lbs. We will designate the airplane as the BD-5C. The cost of the wing is the same as the BD-5B wing. As soon as we finalize its design we will offer it as an optional wing.

BD-5 Air Freight Rates

This information, together with a completely detailed routing and timetable schedule, was compiled by Mr. D. Jay Holloway, Customer Service Agent for Continental Airlines, who is also a BD-5 customer (Priority Number 917), and will serve to give all BD-5 customers some idea of freight charges involved should you decide you want to have your BD-5 shipped air freight.