Hello guys,

My friend flys a Feibao Hawk with 12Z with Spektrum module and Rx + 2 sattelites.

This setup has been flying well for some time and today he had his first problem. He wanted to alter the CG so he moved the ECU pack to the back for the second flight (first was good), which was about 2-3" from the second satelite, and took off. in flight he had lost and regained radio signal but managed to land the model with just a cracked LG mounts.

Anyway - we would like your opinions about what could cause this, could it be the ECU pack close to the 2nd sattelite ?

BTW for power he is using TWO Fromeco 2600 Li-ion packs with a Duralite Gemini providing twin regulated 6V outputs to the Rx, so i dont see a power issue.

He will send me pics of the setup he used for the problem flight soon, and ill upload them.

Your opinions are welcome.
thanks !

That's why I'm still with the old grandpa 72mhz. 2.4 is still to early for me to try. Two of my friends allready flying with the 2.4 in jets with no problems yet. But their isnstallation was made by Andy Kane in the states. I have same plane waiting to be assemble with this tech. Againg this belong to one of the guys I just told. But this time is my turn to do the first 2.4 install. I guess I will look for more ideas here also. Good luck!

Alex

Seems like your area of the world is having some issues on 2.4 Ghz. I know here in the US there are a lot of users , and no one has had any issues that have caused problems you are seeing in the middle east (my reference from the US). There were few problems(2.4) at a rally in Dubai,UAE a week or so ago on 2.4 ? Might be some Local Government project(ECM) that hitting the frequency.

Semper Fi
Joe

Here are the pics of his install. notice the ECU pack on top of the 2 fuel tanks under the small tray with the Festo ball valve.

Notice the 2nd sattelite is located to the left of the main 3.8L tank (a little hard to see in the pics but its visible in the last pic)

I agree with uncle Joe.
Do more testing with 2.4 in the Middle East. Here we had so many success flights. I trust the system enough to put in all my jets.

Guys,

there are many models flying on 2.4 locally with no problem at all !!

Did the owner use the flight log to see how each rx was operating?

Is it just me or is one of the RX antennas bend down fron being pinched by the plywood tray????

WHY not elevate the RX on a 3/4 or 1" thick balsa block just to get it above the clutter?

BTW...I use black brake line on all my RX antennas!

Dave

No data logger.

Dave, good eye - Nessy checked and it was in fact pinched on flight #2 since he moved the ECU batt he loosened the tray..

Do you guys think this could be it ?

Sure didn't help! I wonder what else "slipped by" on the pre flight inspection?

Dave

lior
since i was ther befor that i saw that the second sattelite was to close to the tail pipe and the turbine
her is nessi hawk before that hapened
i took those pic today
http://d-spot.co.il/forum/index.php?showtopic=145109

Works great in my Hawk!!!!

Udi, thats strange, i disagree.
this plane has flown several times before (including today!) with no problems !!

lior
as you can see i took those pics today and the hawk flew flawesly befor that hapend
i think that could be the problem or a magnetic filds from the bat that removed from the nose towards the fuel tanks and the sattelite udi

I have the remote in my hawk mounted on the center of the plywood plate, and not near the carbon fiber tape in the nose section. I'm using the DX-7 for guidance. The carbon tape was a concern for me.

One other thing I would do is rotate the remote antenna 90 degrees

"To a vertical orientation"

Good advice!

Dave

So no one thinks this could be due to the proximity of the ECU pack to the 2nd sattelite ?

No, not really. While the ECU pack is (obviously) connected to the ECU and thuis could possibly conduct some nosie from it, that is very unlikely to cause a problem - mainly because the noise sources in the ECU are very far below 2.4 GHz...

Bob

OK guys, in that case - keep the ideas coming !

It looks like you have a total of FOUR Rx's. If you lost signal to one, another will take over. You may want to look for other problems such as loose connections . The ECU battery most likely had no ill effect. This Rx has the long recovery time, so is it possible that it was other than a loss of signal? Just asking!! I tried my 10X and the spektrum 9 ch conversion set for loss of signal, and it took too long to recover on the ground (I would have crashed in the air if this was a real situation). I think the new Rx's have a new software to allow them to recover faster from a loss of signal. I would do a thorough range check next time too!

Did you do a full 360 degree range test on the ground, engine running? Even with 2.4 it is critical to do a range test (using the reduced TX signal procedure outlined in the Spektrum user's guide) from all aspects...kind of hard to do this from the top or bottom, but rotating the plane through a full 360 degrees while at max range on the ground can help identify any issues. Should be done for all new installations and any time you move/change electronic components.... also, at $24 or so, there is no reason for not using the data logger... just my $.02...at 72 succesful Spektrum jet flights and counting.

Barry

battery power is the biggest cause of lock out with 2.4 as everybody knows but I think you should get the rx's upgraded with the new software as Ehab says. - done for free by Spektrum/Horizon

For me there is a clear rationale that says that if it worked before you moved the component, and now it doesn't, move the component back and try again. If that works, you have your answer.

Just a note - with the ECU pack in the nose (original position) we did do the 360 degree range test successfully, before the maiden.

It has flown about 5-6 flights since then successfully, and when the ECU pack was moved yesterday, Bang !

About battery power, i personally flew the crap out of this plane for several flights. so if there was a battery \ current problem, i believe i would have gotten to see it prior to yesterday, when i was flying it. the owner of the plane doesnt do too much aerobatics, so he probably doesnt have a very high current draw when he is flying.. and with the Gemini and TWO fromeco packs @ about 6-8C each.. i find it extremely hard to believe this is the case.