Over Thanksgiving in New Hampshire my Dad and I had some time away from the family activities to try the Jato-E-zagi. We had mixed results as you'll see below. If you don't care how we set it up, skip the next few paragraphs. First, we hooked up the second speed controller in the Ezagi. Originally the plane was setup so that the first speed controller (an FMA originally suppllied with the E-zagi) was plugged into the throttle (on a 535 rx) and the elevons were plugged into the elevator and aileron and mixed to act correctly using a JR8103. The second speed controller (a Jeti-14) was then plugged into the rudder slot. Two accomodate both speed controllers (giving power to the motor and to the rocket igniter) we made a Y-connector out of Deans plugs soldered side-by-side and plugged both controllers into the battery (an 8-cell AR pack). To avoid problems that we imagined might occur if _both_ speed controllers were trying to power the receiver we removed the red (plus) wire from the connector from the Jeti-14 speed controller to the reciever and put heat shrink around it. We imagined that if both speed controllers were supplying slightly different voltages to the Rx then one might inject current into the other and not knowing how either functions we thought it best to avoid this problem. Rather than cutting the power wire from one speed controller we could have put diodes in the connectors from the speed controllers to the Rxes. Next I added a mix to the radio so that the rudder stick on the transmitter was silenced and couldn't drive the Jeti-14 speed controller. (Mixing rudder->-100%*rudder). I adjusted the rudder sub-trim and offset so that no voltage could be measured across the Jeti-14 output. I next mixed the Aux-2 pot to the rudder so that rotating the aux-2 pot on the transmitter gave 0-10.5 volts on the Jeti-14 output. I also adjusted the rudder travel volume a little. Finally I made the mix dependent on the butterfly switch on the transmitter. In this way firing the rocket motor on the zagi was dependent both on turning the pot all the way up (arming) and flipping the butterfly switch (firing). Now here is something that is a _little_ disturbing but we found it not to be a problem in practice. When I measured the voltage across the Jeti-14 with just the FMA speed controller turned on (and the Jeti switched _off_) and I ran up the _throttle_ servo I got a 'floating' voltage of up to .7 volts across the Jeti's output (for god knows what reason, the other stick movements didn't do it) but when I turned on the Jeti-14 and 'excercised it' by turning up and down the aux-2 pot I could get a solid 0 volts across the Jeti-14 output regardless of the throttle position or any other sticks. This was a little worrisome because we wouldn't want the rocket going off prematurely. It induced us to check this before _every_ flight _before_ attaching the igniter to the Jeti-14 output which is good practice anyway because we didn't want to set up the engine with hot outputs from the Jeti. I can only hypothesize that there is some capacitance in the Jeti-14 that charges up and gives 'positive control' after it is turned on and used. But it wasn't very reproducible and I couldn't short accross any of the Jeti's leads and then reproduce it. Anyway, confident that we could get rid of the problem if it occurred (by running the rudder channel) so we went on to flying.... Based on my prior (good) experience with the global explorer we put a D11-P (plugged engine) on the bottom of the E-zagi so that the nozzle of the engine was approximately at the CG of the plane (~4 in back from the trailing edge) and 3 inches off the bottom (measured from the center of the engine) to keep from cooking the bottom of the Zagi. The engine was supported off the bottom of the Zagi by a block of EPP with a quarter inch EPP skirt hot-glued onto the base to allow taping the block to the zagi. The engine was housed in a cardboard tube with a standard Estes 'retaining spring' to allow us to change the engine easily. The skirt also went back to the trailing edge in hopes of protecting the zagi a little. Now some of you may be thinking: This guy got away with putting the rocket motor on the CG of his global explorer but a flying wing is different--it has a much lower moment of inertia about the CG-- and you'd be right! Here's what happened--I motored the plane (normally 20oz, now 24 oz) to probably 100 feet of altitude and hit the rocket motor. The Zagi did 5 loops in 2 seconds!!! They actually were only technically loops, the zagi tumbled end over end about its pitch axis 5 times during the burn of the motor (advertised at about 1.8-2 seconds) and moved an indeterminate amount forward and downward (not more than a few feet) when the 'New maneuver' was complete I let the zagi gain a little airspeed (a couple of feet down) and resumed level flight. The whole thing looked like a 'hiccup' in the air. It was so fast that visually I only registered 4 'loops'. My Dad who is a Ham and used to listening to morse code says that there were 5 'whoooshes' as the plane whirled around and upon thinking about it I agreed that I heard more than an 'H' (4 whooshes). We were impressed that we had invented a new maneuver but a little embarrassed that we hadn't anticipated it. Next we decided to move the motor back to a position on the bottom of the wing that was symmetric with the position of the motor on the top of the wing. This necessitated the addition of another ounce of lead (to 25 oz). We decreased the epp spacer so that the edge of the rocket motor casing _just_ cleared the propeller descending from the top of the wing. We hoped that with the thrust along roughly a line parallel to the motor's thrust at a similar position with respect to the CG would give a nice acceleration without the 'loops'. We motored up and fired the rocket--the plane was unperturbed-- and the rocket engine left the plane like a rocket! Instead of overcoming the inertia of the plane it broke out the cardboard ring holding it in the engine mount (and gotten away from the spring clip) and streaked ahead of the plane (in my Global explorer experiments I had taped it down with copious amounts of duct tape rather than trying to used a nice cardboard tube mount.) Rather than try again immediately we decided to reload the mount with an empty rocket engine that we had modified to carry an 8 inch length of piano wire that would act as a launch rod for small 1/2 A size rockets. These rockets were made by adding cardboard fins to the body of a 1/2A or A size rockets, filling the top of the motor with red powdered tempera paint as a 'marker charge' and capping with cones made from a fireable 'plastic' modelling compound. These were tiny rockets that we made years ago in anticipation of making 'air-to-air' rockets and we finally had a set up to fire them. We set off two of these rockets at altitude uneventfully--they streaked away from the plane leaving a nice 'trail' and terminated in little puffs of red (really tiny barely resolvable). Finally we took off the cardboard mount and decided to tape a D motor to the zagi as I had on the explorer in the position that was symmetric with the electric motor. We used strapping tape rather than duct tape and darn it, again the rocket engine left the plane (just like the little rockets) this time breaking all of the strapping tape we had used to explore it. So that's where we are--we've invented a new 5 'loop' maneuver, proven little air to air missiles, unintentionally proven D sized air to air missiles, and we need to make a better engine mount that won't break out. But we ran out of batteries, light, and time--so the Jato-zagi remains for another vacation. later, Paul Rothemund RCSE-List facilities provided by Model Airplane News. 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