Pete C

John - I have created an additional TX model memory using the file you kindly sent. I now have three different versions for the Heron that I am working with. As this is a new TX I am keen to get familiar with its functionality so that I can apply that knowledge to the set up of of my other current models as I move them over to the DX9, and also a few still in the pipeline. To that end, the detailed information you have sent to me today is invaluable. Thanks very much. I am currently playing with a set up that has Cruise, Thermal, and Speed as three modes on switch 'B' with the crow braking available whilst in the Cruise mode, and then using the two position switch 'A' to toggle between crow and throttle on the throttle stick. I am very appreciative of the help and advice that you and other forum members have offered to me, it is a great facility both informative and friendly.

Frank: Thanks very much for that I will check it out.

Steve H - Its a Heron that I am currently setting up. It is my intention also to use the throttle stick in dual function in the same manner that you describe. If you have by any chance used a Spektrum TX to set up the switch function I would be interested to know how you went about setting it up. I have used this functionality before when I was competing in electric height limited competitions but I was then using a JR TX. I remember that it took quite a bit of trial and error to get this initially set up but it worked great. After the motor run a flick of the switch meant that you were ready to deploy spoilers for the landing. Having remembered to first move the stick back to Down. I also would not consider using throttle via a switch.

I thought this might happen! Peter, I do not consider there to be a right or wrong way round when it comes to operating crow/spoilers, just personal preference. Thinking back to when I first built a model glider with front hinged 'barn door' type spoilers (about 40 years ago) it seemed logical to me to operate them with the stick moving upwards. This was generally in common with most of my then club members some of whom are very well known names in the model flying fraternity. I do not recall at that time, there being any consideration given to relating the stick movement to full size practice. It was just the norm with the people I flew with regularly. In common with Frank's friend, I have become very used to the rudder function being from the down stick position. Please note that I have not referred to where on the transmitter the throttle/spoiler stick might be. Some people fly with different stick modes and again I do not believe there to be a right or wrong mode just personal preference or maybe first flights were done using that particular mode. Additionally, just to spoil your day, I also use the same stick orientation for throttle control and spoilerons! Frank: I am not familiar with 'aileron differential suppression' and do not understand your description.   Edited By Pete C on 18/11/2019 13:18:22

For the benefit of anyone trying to get their crow to function from the THR stick with the crow being deployed as the stick moves from 'down' to 'up', I confirm that it is achievable. Camber System screen. Input: THR (throttle stick) Offset: negative value Typically POSITIVE values in the UP column. Typically NEGATIVE values in the DOWN column. It will be a case of trial and error so put in some values and move the stick to see what happens. When you get the desired directions for control surface deflection you can then work on the values to get the amount of movement required. Have fun Pete

John, thanks for the message. I have now sent an e-mail to you. Pete

Steve, yes, I have set up the crow function via the Camber System page.

Thanks for the responses: Shaun, unfortunately this facility is not showing as available. I think it must be disabled when you select the 4 servo wing type. Steve, yes, I think this is the problem. I just wondered whether anyone had managed to find a way of reversing this function.

I recently purchased a DX9 transmitter and I am currently trying to set up a 4 servo wing glider. I have managed to get crow working mostly by trial and error (the manual is completely useless). To activate crow my preference is for the throttle/spoiler stick to be in the 'down' position for normal, and for the crow function to be progressively applied as the stick is moved upwards. Currently it is working opposite to this. Does anyone know how I can reverse the function of the spoiler stick to achieve my requirement? Everything I have tried so far has failed. I am aware of the different preferences that people have regarding the direction of this functionality but my preference, and the one I am familiar with, is the one described above. Thanks Pete Edited By Pete C on 14/11/2019 22:28:09

How nice to see that there is still interest out there in the superb MPX Fiesta. I have an immaculate example, not flown for a few years but ready to go. I can comment on a few points recently raised via this thread:- The C of G starting point should be 88 mm, behind the root leading edge (extracted from the building instructions that I have filed). The tailplane does indeed have a lifting section by design. I do not remember exactly when in the 1980s I actually bought my kit but I recall that it featured a built-up wing. A couple of weeks later I saw that they had brought out the foam wing version so I was able to return my purchase and exchange it for the foam wing (SF) version. As I was into Cross Country at the time I also reamed the foam wing cores to accept thin brass tubes for lead ballast plugs that were available from Multiplex. The ability to increase the wing loading proved very useful on a number of occasions. I am intrigued by the comments regarding the 'sit' of the model in the air. I suggest that it is worth experimenting with the C of G as with an all moving tailplane it is relatively easy to get the model to fly acceptably but not to its optimum. There is a simple check for the correct C of G position. When at a safe height, but clearly visible, push the nose down so that the model is in a 45 degree dive. Then, release the stick to return to neutral. What you want to see is the model slowly climbing back to to attain level flight after maybe a few gentle oscillations. If the C of G is too far forward, after releasing the stick back to neutral, the model will probably zoom and maybe stall. If the C of G is too far aft the model will increase in the dive and will need to be gently brought back to level flight by carefully applying up elevator. Corrections to the C of G should be achieved by adding or removing nose weight. Compensating for an incorrect C of G by just adjusting the angle of the tailplane in relation to the wing (decalage) will inevitably cause problems. If you suspect the model C of G to be incorrect it is safer to begin your adjustments from a slightly nose heavy situation. Apologies if readers are already familiar with these basic C of G checks. I also built my Fiesta with mini servos in the wings for the ailerons and I used the suggested fuselage located single servo for the air brakes, I fitted some double bladed MPX air brakes. I have also found that applying opposite aileron and rudder results in a controlled side slip that loses height effectively. I also built my model with a closed loop rudder system using crimped plastic coated fishing trace wire. This was my usual rudder solution and I also incorporated 2 small strong springs attached to the servo clevis connections. This provides a safety link if the rudder gets impacted whilst landing.

Mike, I sent you a message via the site but have not received a response. Are your contact details correct? Regards Pete

Mike: I do still have the instruction booklet. What queries do you have apart from the ailerons which are taped top and bottom? I put servos in the wings to drive the ailerons and a closed loop on the rudder. These are changes I made as the original instructions have the ailerons driven by pushrods/bellcranks and a snake to the rudder. I also removed a couple of foam cores from the wings and lined them with thin brass tubes. I was thus able to add quite a bit of lead ballast for windy weather cross country competitions. I also added Multiplex double bladed spoilers that are very effective. Tom: I assume the China reference was aimed at me as I mentioned China in my earlier posting. My comment was directed at modelling in general but you are correct that China is not a source of large thermal models. Eric: A project to complete for flying this summer?

Can anyone give me advice on mixing the throttle stick (e-motor) with the spoileron (ailerons) function on a JR X2720 transmitter? I am needing the throttle to control the electric motor during launch but then to switch the function to spoilerons for landing.   I ideally want to have proportional control of both functions but if this is not possible I will have to settle for proportional spoilers and a switched motor I guess.   Anyone like a brand new transmitter?   Pete

I have an immaculate Multiplex Fiesta that I have just finished a full referb on.  I have flown it extensively and it is a superb flier.  I did not bother to fit a hook as I used it off the slope including quite a few cross country competitions.  It has a quality glass fuselage and foam verneer wings I also fitted double bladed spoilers.  (When first released the Fiesta kit had built-up wings).  As with many gliders, speed is determined by the wing section, the weight, and what you do with the elevator.  I do not think that you can get much of an idea of how a model flies by watching You Tube. I have just returned to modelling after a ten year layoff.  I am rather disappointed that models such as the Fiesta are few and far between and that most of the modelling skills now seem to have moved to Chinese factories.  There is much to be learnt by building a model and researching the many aspects of design and construction. Fortunately I still have some 'kits' which I paln to 'build' e.g. Airtronics Sagitta 900, and Airtronics Legend.  I do not believe these to be available today except possibly as plans, Airtronics no longer exists.