Last week I had what seems to have been a radio glitch. I was flying all day fathers day at my local club. Later in the evening on a flyby I went in to a half cuban. I went inverted and when I tried to pull out I lost contact with the plane. The plane went in to a downward spin, it would not respond. Right before hitting the ground I was finally able to get control of the plane, but it was to late. The plane hit hard and cracked the fuse and broke the wing tip. I tested the radio/servos after the crash and everything worked fine. I easily repaired the damage and re-covered the plane.

I went out yesterday to get the plane back up in the air. I did a range check and it seemed to be ok. My first flight went fine, the plane responded with no problems. On my second flight it happened again. Half way though the flight I was flying by at half throttle at about 150 feet. when I went to turn I had nothing, the plane kept going straight and the lost altitude and crashed. Tested the radio and servos after the crash and everything was working fine.

I ran the plane on 5 or 6 different occasions before any trouble started. Never had any glitches before the fathers day incident. I also have another plane I fly on the same channel and I have never had a problem. Could this be a receiver malfunction?

Info...

GP Super Sportster 40 Kit
O.S. FS-70 II Surpass
4 Hitec HS-325HB Servo
Hitec Electron 6 Receiver
Hitec 4-Cell 4.8V 600mAh NiCd Battery
Hitec Eclipse 7 Transmitter

Do you load test your batteries ? 600Mah scares me to death. If yes , I would set the gear up on the ground let it stay on for the same amount of time you fly before you crash and see if you lose signal. Something can be shorted in the receiver and after it heats up the problem may occur. GL.

What should I be using? I only fly at 10 minutes at a time. I have a volt watch 2 on the plane, I can get a good 5 or 6 flights with only a slight drop in voltage...

Although this may not be why you are crashing, 6 flights with a 600Mah battery is impossible. I have a hanger 9 Digital Variable Load Voltmeter. The voltwatch is telling you the voltage when the servos are not under stress. (ie. not many Amps being drawn when plane is not in the air). On a 900Mah battery I could only get 3 flights on a trainer. Your plane is a sport plane and uses much more Amps to keep it flying because it isn't a floater. GL

I have flown my GB eagle 2 (a trainer)for 5 or 6 flights for 10 minutes at a time on the same type batteries (600Mah). I have done this many times without recharge. Also the plane was only on its 2nd flight after recharge before the crash. So I don't think the batteriey was the problem either...

5 or 6 flights on a 600mah pack is very plausible. Not to bash electronic manufactures, but I have never been a Hitec fan.

I have also flown my planes (600mah) five or six times with no voltage problems. I usually don't quick charge untill the fourth flight but I know I can safely go to six flights and that's with a lot of servo use.

You are really asking for problems flying that many times on a 600mah battery on any plane. It becomes a matter of time. The only real way to know for sure is to use an expanded voltmeter (one that properly loads the battery) and checking to see what the voltage is before going up. It it is anywhere around 4.9 I would NOT fly, I would recharge.

What's the problem, anyway!! Recharging seems to be a simple solution, or at least a precaution to prevent a crash, eliminate that bad link in the chain of events that causes crashes.

Go to the people that make chargers.. sirius for one, has a pretty good section on batteries and the do's and don'ts about batteries, and he will tell you that it's a simple matter of math. Four servo's for 5 10 minute flights simply does not add up, and you are definitely headed for a crash, even if you can justify the last crash as not being from a dead battery, eventually, at that rate, you will have one. It's not if, but when.

I do not regularly fly with out recharging. I was making a point that it was not impossible! I was just saying I have done it. That is not the issue here. I recharged before the first flight and I checked the battery after the crash with a volt meter and it was fine...

Could we please get back on track. Does anyone have any other clue on what could have happened?

I ttrained with my LT-40 and a 600 mah pack. Flew 6-8 times a nights, no voltage problems. Soooo...what to check next? If you have another reciever, you could try that. You might also look at the Rx crystal.

Geez....FWIW, 600 ma. pack on non-digital servos is no problem ....generally, servos draw little current if not in action. I have been flying 4 flights without charging with 500ma. packs for more than 20 years with never a battery failure. That beign said, 1000ma. packs are so cheap today, it's a no-brainer...lol...don't fly if the loaded voltage falls below 4.8volts...big_G

Food for thought..possible temp. issue with microscopic crack,making and breaking contact in PCB board,or one of its`essential,electronic components.this type glitch will come about and go away with expansion and contraction.It`s quite ellusive, one minute its there,the next it`s gone.Gets expensive too by being real hard on the plane(crashing)[:@]Personally I think I`d go the new receiver route as opposed to totaling the aircraft,and then still needing a reciver,and,now a new model.If you can find the crack in the board it can be repaired,if not it will be $$$$$ after $$$$$$trying to find the actual fault. Open, up that reciever check the antenae connection,look for the obvious if you can`t see anything just get a new one.From what I can gather it dosn`t sound like it`s transmitter issue because your using that radio on another plane with no trouble,right?? well thats my thoughts and hope fully you can straighten things out without too much wasted cash....FLY for NOW!!!!!!! DAVE B.
ps. having problems with computer here. hope you wern`t waiting on this, sorry if so.

Just because you have good voltage, and most of test it static, doesn't mean you have enough power to run a system. If you are low on amperage then you may not have enough to serve all. Also when we are flying the control surfaces have to work against the wind, centrifugal forces, and gravity. A static test that gives you say 4.9 volts may dorp when pushing surfaces loaded in flight.

Even so, a voltwatch will flicker and the display will change if you simply move several surfaces at a time or if you "load" a surface by applying pressure on something, like he said, it isn't a battery issue here, It sounds like the receiver is bad, and your best bet it to go for a new one. Good luck, get back on the sticks...

If it was infact the receiver then why did he get a good flight the first time when putting it in the air after the rebuild?

So many times we blame our radio because it is the easiest thing to blame it on and the fact that we don't or can not find the actual problem.

The plane was flying along fine in straight and level flight and suddenly would not respond to the "radio" sticks. What would you like to blame ryanpilot, the family dog? Sorry but it seem obvious that something in the radio system is acting up whether it is the rx, batt, switch harness or whatever is what has to be determined. An intermittent condition is entirely possible, I see them daily on the full scale aircraft radios I work on. A micro-fracture or a little solder ball rolling around inside the rx case can drive you crazy. You could always send any suspect parts to the mfg with a good description of the incidents so they will know what they are looking for. The more information you provide a tech, the better your service will be. Nothing is worse than a complaint like "don't work right". The tech can run hot/cold tests as well as vibration and check the boards under a microscope for damage. Or you can just throw money at the problem and buy a new rx and battery pack.

Good luck either way.

I had two bad switches with Hitec radios. Usually if you lose power to the
receiver....your toast.

I use dielectric grease on all my connections to improve the reliability of
the connection.

FBD.

Flyboy Dave, I would bet the you use good quality switches and gear. I quit using standard switches in my planes and went to the Relia Switch from Fromeco. Guess what, have not had a switch failure since.

I learned my lesson years ago about using quality gear. I don't buy the generic or less expensive stuff anymore. I also learned that when you mix connectors that are gold and not gold that can do funny things to your signal. Now I make sure all my servo leads have gold connectors in them as well as extensions etc.

I switched to the Cermark switches a few years ago, now that's all I use.
There prices are reasonable, and they are close by. Most of the time I get
stuff next day from them. I had a Futaba switch fail on me. They were
soggy feeling....not crisp. I threw out two new ones, the bad one, and the
Hitech switches, and got a bunch of the Cermark's. They have the best price
( I think ) on the extensions and Y's too.

I had three Hitech's that would not charge through the charging lead. []
Try the dielectric grease in the connectors....mash a bit into the female side.

FBD.

You know, it is funny. I use dielectric greese in my float planes. Logic would dictate that it would be a good thing for all of them. I know I use it a great deal on electrical connections when I fix equipment. I used to be a heavy equipment mechainc.

I will have to try the Cermark stuff. I have seen their ads in the magazines but never heard any one talk of them so I never ventured out side of what I knew for parts and plane stuff.

Cermark uses the heavy wire and mostly gold connectors on their stuff,
good stuff. I got into the habit of using the grease when I lived in the harbor
of Los Angeles. The marine air (salty) caused corrosion on everything, the
grease prevented the corrosion, as well as made a super connection.

FBD.

Like I said,can be quite elusive,these come,and,go problems.Amountain of good advice in these threads.What its all boiling down to though is YOU have to "systematicaly"track down the source of the trouble.DON`T go willy ,nilly about this,verify everything and leave no doubts about any of the components either by replacement with known"good"parts,or having a certified electronics shop QUALIFYING your entire electrical system to be functional and proper.Just be professional about this and leave 0 possiblities of a remaining problem!! My school of HARD knocks lesson for the day!! Sometimes the $1.50 savings on lesser quality parts is NO saving at all.You`ll realize this,as you`re picking up the splinters on the ground that used to be a really nice plane!!Or worse case scenario,when your in court because tha plane hit or KILLED someone!!!This hobby is fun but can be deadly,and it has happened too..Bottom line don`t test by hoping,you`ve got the source of the problem figured out,and then,"flight"testing to find out you were wrong again.It`ll cost you every single time you realize you still got a glitch.Don`t want to be a downer,just trying to keep you playin`HOOKIE from that"school", ya really,really,don`t want to go there!!! By the way,could the antenae be touching metal when the plane gets inverted? But that usually causes some twitching for a second,not,total loss of control.Sometimes can be that simple[X(] Well good luck to ya!! FLY forNOW!!!!! DAVE B.

For those reading this thread that don't know the purpose of dielectric grease, it is a non-conductive (non-shorting) grease which will keep moisture and OXYGEN away from your connectors. These are the two principal agents that lead to corrosion (oxidation) in your connections. It is used a lot in full scale aircraft to control corrosion in antenna connectors. A little dab will do the job.

I'm betting on the switch. Intermittent lose of control can be so many things it's mind boggling. It could be a heat problem relating to the battery, switch or receiver, Vibrations at a specific throttle setting can cause all kinds of stuff. You were inverted so there is the possibilty of the antenna touching metal, a connector working loose when inverted.

Now as far as a 600MaH battery is concerned. Without load testing there is really no good way to tell. The Voltwatch does a decent job even when moving control surfaces but it's not accurate. A standing voltage of 5.0 volts with no load could conceiebly drop below 4.8 when under the stress of flight. Most recievers will drop signal around 4.7 - 4.6 and once that happens momentary to full loss of control is a real possibiltiy. A battery that has never been cycled or just plane old can also drop quickly at a certain voltage.

Personally I never fly below 5.0V on a 4.8 battery no matter what servo's are used. The higher the torque the more the load, the bigger the surface, the more the load.

Well I have taken the receiver and put it in one of my old beat up park flyers. No problems with it yet. I tested the switch harness and it also seems ok but who knows what is happening with flight vibration, so it will be going in the trash. I will probably trash the battery too. I dont want to take any chances...

As for the plane, it’s pretty much trashed. I will not be repairing it. I have already bought a new SS kit. I will be repairing the old wing and save it for back up or something.

I was flying my other plane this weekend using the same transmitter with no problems so I think I can rule out transmitter problems.