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This is waay cool..

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  • This is waay cool..

    Supposedly a hobby model :)

    The new B-29 is 25% larger than the old one. The old 29 had a 16' span. The new one has a 20' span. It has 4 ZDZ 80RV engines turning Zinger 4-blade 24x8 props. The props were made by David Johnson by putting two Zinger 26x8 props together. That was a little more prop than the ZDZ 80 could handle so I cut an inch off each tip and that got the RPM up to around 5300 rpm. Could probably take a little more off but it has performed so well that I quit there. The tips were rounded and then painted and really look nice on the plane.

    The plane started life with 4 receivers, 17 servos, and 9 batteries.
    The outer wing panels with the outboard engines attach to the center section with a couple of wing tubes. To eliminate having to connect any wiring each time we assemble the plane, we use a receiver in each wing complete with it's own battery and switch. Each engine has a throttle servo and an ignition switch servo. There is also a second switch in the circuit for manual shutoff. Each outer wing panel contains a Futaba 5301 servo operating the aileron. This 292 in.oz. servo is also used for each elevator half as well as the rudder. We have a servo up front steering the nose gear as well as a servo operating the retract switch for the electric jack screw retracts.

    We originally used the retracts from the old 29. Soon after we started flying the new 29, it didn't take but one flight landing on a paved strip to convince us we needed brakes, if we wanted to stop the plane! We put a set of Glennis brakes on and they worked ok but weren't entirely satisfactory. So this added another servo to control the air valve that supplied air to the brakes. Also another problem cropped up...the brake valve is mixed to the elevator channel and is operated by applying down elevator. Well, I was using so much down elevator during my flight routine that I was depleting my air supply. So I added a servo operated valve mixed in with the retract channel so that when I retract the gear, the valve cuts the air supply off to the brakes. A couple of years ago David Johnson built an new set of retracts for the mains. These are similar to the original but with many improvements. He also made the wheels and brakes. The brakes are a drum arrangement using air to expand a couple of o-rings against the drum. They have worked great and have not given any trouble. The whole assembly is a work of art! I can't thank David enough!

    The fuselage contains two receivers, one working the left side and the other the right side of the plane. Each has it's own battery and switch. The retracts are operated by an 18 cell 700mah NiCad. I started out with 1400mah NiCad's for the engines and receivers. After a year or so I changed to 2700mah Nimh throughout. Last year I went back and changed to one 2500mah Nimh for each engine and two 2500mah Nimh per receiver with two switches connecting to the receiver with a Smart Fly BatShare.

    I use a JR 10X and the receivers are JR 945 PCM Dual Conversion units. All channels are in use......Throttle controls the #1 engine with channels 7,8,and 9 mixed to the throttle channel to control the #2, #3,and #4 engines. This lets me adjust the idle of each engine and also lets me match them up at half throttle or any other point I feel they need adjusting. Then we have aileron, elevator, and rudder. The rudder channel is connected to the nose wheel servo so I can use the rudder trim for centering the nose wheel. Channel 6 is mixed the the rudder channel and controls the rudder. If the rudder needs trim, I would use channel 6 subtrim. Channel 5 controls the retracts and channel 10 operates the ignition cutoff servos.

    We did the first test flight in April 2002 at Hodges Hobbies. No taxi tests. Just pushed the throttle up and we were off. The new plane is far superior to the old one. It has much more power and lower wing loading and is very nice flying bird. The old plane had Quadra 42s and weighed about the same as the 98lb. new plane with more wing area and ZDZ 80s.

    Last year we added smoke and it has been a great addition to the act. I originally put smoke on the #4 engine just planning on using it during the spin. It looked so good, I then added it to the #1 engine and added more tank capacity so I could use it during most of the flight maneuvers. I have about 13oz. of smoke fluid per side. The smoke system uses two TME SmartSmoker units with each drawing power from a 730mah Nimh battery. Each engine has a 32 oz. B&B tank supplying the gas. We also have a parachute drop unit that allows a couple of crew members to bail out when things start getting scary. Dan controls the smoke units and the parachute drop with his transmitter, remember..... I have no more channels.

    So now where are we?.... we now have 16 batteries, 20 servos, and 7 receivers counting the batteries and receivers operating the smoke units and parachute drop.
    Last edited by Jay; 18 Aug 08,, 17:19.
    A grain of wheat eclipsed the sun of Adam !!

  • #2
    I see these things all the time. There is an abandoned airstrip now far from home and the older gents there have some incredible planes. Some so big they have to taxi just like the real thing.
    Fortitude.....The strength to persist...The courage to endure.


    • #3
      The aerobatics and inverted pass are impressive:
      YouTube - B29 R.C plane with X1 spaceship


      • #4
        Its awesome , must'ev taken a hell lot of time, effort and money
        When our perils are past, shall our gratitude sleep? - George Canning sigpic