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5/25/96
The Mud Duck has been flown many flights and I am glad to report that it is still fun to fly. The most interesting part of flying it is the other pilots reaction. Most agree that it is so ugly that it is cute. I have named mine Fugly. I painted it Cub yellow and by a friends recommendation I put a smiley face on the wheels, with the valve stem as the tongue. I added ailerons and coupled rudder. It still lands at a snails pace. After flying it many flights and then flying a Sportster 40, I am way behind the 40 in reaction time. I built the Mud Duck as a test bed plane and I wanted a slow one. I have installed a BTA autopilot (with altitude hold) and I can't really tell if it is doing much. The Mud Duck (with its dihedral) is very stable. However, the autopilot is to be used for out of sight control. This week I will install Jomar's servo isolator and two battery packs. Next will be a down linked video camera. The current Supertigre 90 will be replaced with two Tower 40's. I intend to make a mount (from plywood) to install on the current motor mount with the 40's on the side. This will be done for redundancy of power as the plane should fly good on only one 40. After the video test, I have a electronic compass that I intend to link to the autopilot for heading hold. Eventually, I intend to install a GPS unit for navigation. This will allow a complete flight path to be programmed and have the plane execute it. Below I have listed all of the modifications that I have done and some recommendations for future builds. Yes, I intend to build probably two more Mud Ducks.
Mud Duck Report Volume 1, Issue 2 It has been a while since I reported on the Mud Duck that I built (May, if I recall) and I thought I would bring you up to date. It still flies great and I have looped it, but this report is to tell about how nice a platform it makes for down-linked video. Late last year I purchased a color camera and 900 Mhz transmitter with down converter from Super Circuits. This unit gave me over 1000 feet of range on the ground. However, I have yet to fly it in a plane. It interfered with the RC receiver to the extent that the range was reduced and I was afraid to try to fly it. I did the following to try to eliminate the interference. I tested both my Futaba FM rig on 72 Mhz and my FM ACE MP8000 with the Prostar receiver on 6 meters (53.3 Mhz). Both rigs had the same interference. I purchased the Jomar isolator unit and used two separate battery packs, plus I housed the receiver and isolator in a metal box with everything receiver related tied to a common ground. Additionally, I tried about every possible scheme to try to eliminate the problem. In testing, the TV transmitter only caused servo jitter when the camera was actually modulating the transmitter. But what good is a carrier with no video? I was at the point of building low pass filters for the RC receiver when I attended a demonstration of a video (Black and White) unit that was on 440 Mhz. The owner related on how much interference he had had with his unit and he finally found a receiver that worked the best. As far as I was concerned, when in a 60 minute demo I got to see about 3 minutes of decent pictures on a green monitor because he had to constantly adjust the down converter. I decided at this demo, this was not the route that I wanted to pursue. I wanted reliable video and not the challenge of tuning transmitters/receivers, been there done that! The next day I called PlaneTalk and talked to Monte Salot about his system. I asked, "do you sent it and I install it and turn it on and it will work with no experimentation on my part?" He said "YES" and I said "SEND IT!" It arrived three weeks later as he said it would. I installed the PlaneTalk system with no special filters etc. on the RC radio and everything worked great, just as Monty said it would. This unit is on 2.418 Ghz and is FM and not AM as the other rig. The picture and reception is great. IMO, if you are serious about video, buy the unit from PlaneTalk. You can get by with less expense with some of the other rigs, but be prepared to experiment. Now, back to the Duck. The Mud Duck is so big and slow that it makes an ideal video platform. I used the supplied fixture to mount the camera for tilt and rotate viewing. It is a rather flimsy thing and I thought that the camera would jitter a lot from engine vibration. However, much to my surprise, the only jitter I get is at an idle on the ground and not any other time. This Duck is powered by a Supertigre 90. For the future, I am wrapping up Duck #2 with a nose wheel and two 40's mounted hammer head style. The tri-geared Duck looks rather strange but I think instrument landings (looking at the TV monitor) will be enhanced, I have yet to try. I intend to install the BTA autopilot and GPS system. I will then build a micro computer system for control for complete programmed flight. Hopefully, I will test this next spring. Dan WB4GUK AMA 32873
Mud Duck Report Volume 1, Issue 3 9/22/96
Mud Duck #2 has just been test flown. It was built as a convertible and has a nose wheel and tail wheel. Simply removing the nose wheel and turning the main gear around converts it to a tail dragger.
I am unhappy to report that the tri-gear test was a failure. I was able to get it airborne after about a 500 foot ground run (usually takes about 10-20 feet). This ground loving can be caused by two major factors. One is that the built in down thrust tends to pull the nose in a downward direction and puts abnormal pressure on the nose wheel which causes drag. Two is the elevator is on a T tail and due to no prop wash it has no authority until sufficient speed obtained. I lowered the nose wheel some to increase the angle of attack and it helped some. In order to increase the AOA enough, the nose wheel would be so long that the plane would look like a tail dragger anyway. Therefore, I converted it back and it flew just fine. Some things are just not meant to be changed. The hammer head configuration with two .40 engines was a bit more successful. With both engines running it flew similar to Mud Duck #1 with the 90. However, at this time the 90 version does appear to climb better. I am going to weigh both planes as I believe that #2 is heavier that #1. Much to my disappointment, it will not fly on only one 40 running. On the first two flights, one engine quit each time. The single engine will simply allow you to stretch the glide.
Dan
WB4GUK AMA 32873 EAA 60974
Mud Duck Report Volume 1, Issue 4 11/17/96
Mud Duck #2 was modified from two .40 engines to three .40 engines in the same style of hammer head configuration. The three engines do perform a little better than Mud Duck #1 with the single 90. However, with the onboard glow driver that consist of three 4400 mah nicads it weights 3 1/2 lbs more.
In the last report I had not weighted the planes. I include my weights for your comparsion, if you have a Mud Duck.
Single .90 16 lbs Double .40 17 lbs Tripple .40 19.5 lbs with 3 4400 nicads and extra fuel tank.
Dan
WB4GUK AMA 32873 EAA 60974
Mud Duck Report Volume 2, Issue 1 9/18/97
Since my last report in the last part of 1996, I have built and flown two more Mud Ducks. These additions will finalize my flock of ducks.
The Mud Duck 40 was built by multiplying the 108" MD plans by .707. This yields a plane of 78" (6 1/2 feet) and one half size as it pertains to volume. I powered it with a Tower 40 engine and using an 11 x 4 wood propeller. It weights 7.5 pounds empty. I used the Trexler Airwheels from the large Lazy Bee. These wheels blow up to about 6 inches. It flys just like the 108 inch Duck.
The Mud Duck 380 was built by multiplying the 108" MD plans by 1.414. This yields a plane of 165" (13' 9") and twice size as it pertains to volume. In some cases I was lazy and used 1.5 as the multiplier for convenience. I powered it with a G62 engine and using an 22 x 6 wood propeller. It weights 40 pounds empty. I used 5.00 x 5 intertube from a full scale airplane as the tires. It also flys just like the 108 inch Duck.
Since this plane is so large I will give some details as to the building.
It used 6.5 sheets of 40"x60" foam board. a lot of hot glue and eight cans of Pactra Formula U paint. Standard Futaba S148 servos were used on all controls. However, all moveable surfaces have dual servos. Two each on the Rudder, Elevator and each Aileron. A total of nine servos were used. I used standard servos instead of 1/4 scale servos so that the force would be supplied to different points on the surface. Since this plane is so large I built the fuselage to separate at the bend, just behind the wing. The two pieces of the fuselage are retained by the same type of hinges and pins that were used on the wing struts. The horizontal stabilizer is also pinned and is removable. The horizontal stabilizer is not flat as is used on the 108" Mud Duck. Instead it uses the same ribs that were used on the 40 size wing. I did this, not for a lifting surface, to give it rigidity. It was just two large to be built flat.
I initially installed an OPS 30 engine, but it would not pull the plane enough for flight. Therefore, I installed a G62 Zenoah engine with an C & H electronic ignition. The 50 ounce fuel tank was retained.
The radio installation consist of the micro FMA receiver with a Jomar servo isolator. I used the isolator as a precaution since there is 60 feet of servo wire in the airplane. I used a separate wire to each servo. In doing the calculations for voltage drop for such long servo leads (four are 12 feet long) I determined that using a separate lead for each servo resulted in less voltage drop that using a single lead of larger wire for two servos.
An interesting note here, it was simply happenstance, that the largest airplane that I have is using the smallest receiver that I have.
Dan
WB4GUK AMA 32873 EAA 60974
4-1-96
Swiss Navy Torpedo Spotter and Hay Bomber - - - - - -
This model is a replica of the WWI Swiss Navy Torpedo spotting aircraft.
This aircraft was used in the war to spot torpedoes that were fired at Switzerland's ships. When a torpedo was spotted it was knocked off course by using the landing gear to bump into it. To keep the aircraft from dropping too far into the water the large wheels kept the aircraft afloat.
During the harsh winter of 1918, when the ports were frozen, this aircraft was used to drop hay to the animals in the Swiss Alps to prevent starvation.
Sponsored by Aircastle Custom Products, Inc Embedded Computer Specialist and R/C Products 606-293-6884
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