Problem with Mercury SRS gyro with 18MZ

  • Richard,
    I have been flying a Pari-Tech Natrix since September of this year logging 18 flights using the Mercury SRS with a Futaba 18MZ and 6303SB receivers. I was attending the Best in the West Jet Rally last week Oct. 4-9 and made approximately 10 flights on the plane. At this point I got help from Ali Machincy to activate the IGyro in the Mercury and with his help used the setup assistant and then the test fly assistant. Ali offered to fly the plane on the first flight to adjust the gain and make certain everything was functioning normally. After about two minutes of flight and dialing up the gain slowly the plane made a hard 1/4 roll before Ali regained control. He flew for a few more seconds and the plane made two fast full rolls to the right. He switched off the gyro and immediately landed without further incident. I then had Trond Hammerstad look at the plane and he suggested that I should be using 7003SB recievers rather than the 6303's I had in the plane albeit I had made nearly 30 flights on the plane without incident. I completely trust Trond's advice and got two new 7003SB receivers from a fellow Team Futaba pilot. Trond and I installed the two new receivers and then Ali flew the plane again. This flight had the same result with the plane losing control after the gyro switched on and the gain began to be dialed up so Ali landed again with the gyro off. I flew the plane the rest of the event with the gyro turned off and had no further incident, the radio functioned normally.

    Trond and Ali suggested I ask you for some help and said I could tell you that they helped me and could not figure out what was going on. What could be the cause of this issue? I am afraid to turn the gyro on to finish the gain adjustment and fly it with the gyro function. I love the Mercury SRS but want to be able to use all its function with my 18MZ.
    Thank you,

  • Hello,

    this sounds like a wrong gyro direction on the aileron, but with this two expert on your side I think it is something defective- maybe sensor.
    Did you ever test the gyro on the ground? Going into the Testfly assistent on the ground- looking at the ailerons what they do?

  • Ohh my god, I had the same thing happen to me, except mine did 2 fast rolls, Before doing the rolls the IGYRO stopped responding to inputs and I could not get control of it, I had to flip between mode 1 and mode 2 and then mode 1 - 2 - 3 and back to mode 1 (gyro off) to get it to respond I was 10 feet above the ground.

    This all happend as I attempted to perform some 4 point rolls, I was in gyro on (mode 2).

    I also have a futaba 18mz and was 2x r7008sb receivers. After reading your post I think I may just need to take this mercury out of my plane :|

  • These two incidents sound far too similar to not be related in some way. I must say that Powerbox has asked that I send my unit back so they can inspect it, which I have done. I appreciate their support and willingness to try and solve the problem.

  • Darin,

    this two cases are totally different: your problem came in that moment when you turned on the gyro - you had no problems without gyro. This sounds for a sensoric proplem- if you are sure the direction was correct.
    Alkalines problem was: he was flying with gyro on- all working several flights with gyro. The he suddenly lost control. This looks like a signal loss of receiver- not like a gyro problem.

  • I had 0 problems with signal when using the srs competition, now on the first flight with the mercury I have both receivers fail? I don't think so, the plane also did 2 rolls, I had the Mercury set to HD if anything it would have held that spot. I think I will just return the other 2 units that are new in the box and sell this one because it sounds like you guys have already made up your mind that their is no way your unit could have an issue, despite the fact that it is less than 1 year since introduction and 2 pilots have had problems that Extremely similiar using the same radio setup. :geek:

    lost faith in your products....

  • Hello,

    as you had made your mind fix that the Mercury is the problem, I cannot help you... I can say: the series has no problem, but I can´t say that your unit is not bad. So if you have two more: test another one.
    One more question: if you are running the turbine on ground - in all RPM - are the surfaces still when gyro is on?

  • Please explain what you mean by:


    One more question: if you are running the turbine on ground - in all RPM - are the surfaces still when gyro is on?

    If you are saying if I tested the gyro on the ground then yes, however, I take off with gyro turned off and turn it on in the air, for landings I also have the gyro off.

    For for trying the other 2 units:
    I'm not going to open the other 2 unless powerbox wants to issue me a refund for open units, I purchased them from Duralight Batteries and they do not accept returns for opened items. I can not risk my jet just to "try" the mercury, it is a safety issue and a financial one. Believe me if I was the only one that had issues I could say, ok lets try, but after talking to people I have on good Authority that even Bob Violet from BVM lost a model because of the IGYRO, similar situation where the unit would not respond to input.

    Most of the people that are using the igyro are using the 3e unit, very few people appear to be using the integrated units, perhaps there is a problem with this setup? Sbus Issue? Not entirely sure, however, I think you guys need to do some research before making a conclusion that your units are fine.

    Again, my posts were not to cause problems for powerbox, but just to provide you with notice form the field, we are having issues :cry:

  • I have some updates, my vendor suggested I adjust the frame rate, this is something new that I am not familiar with. What should be the best frame rate for Futaba Sbus? I am using JR 8911HV servos on duralite 7.4 li-ion batteries.

  • Hello,

    standard is 15ms- you can make 12ms. But I think this is not the problem. But what you can check: the S.BUS output must not be at "HighSpeed" (7ms). This is a setting in the receiver.

    What I meant is: Model on the ground, Gyro on, Turbine test run in all RPM ranges. Have a look to the surfaces if you see any movements. If the surfaces glitch at any turbine speed, then let me know and send me a picture of your mounting situation.

  • Richard-
    Thank you for your correspondence. I have returned my Mercury as you suggested which I believe you should have received by now. I appreciate you working with me to help solve the problem. It is not my intent to point fingers at Powerbox rather just solve the issue whether it be a radio setup problem or something else. I just want to be able to use all the great features of the Mercury with the 18MZ. Thank you again for the help and I look forward to hear what you find or suggest.

  • Hello Richard-

    I wanted to check with you on the Mercury I sent to you for diagnosis pertaining to the incident described at the beginning of this thread. Just wondering when I might expect to get it back and what you may have found.

    Thank you-