dignlivn

Wondering how many crashes go unsolved ?




My trust Stik expired today. Post crash data,
Rx battery 5.4 volts (4.8 Battery) Tx 10.6 volts.
Rx still on ,at crash site. Using 2.4 system with a
2000 mAh nMhi Rx battery.

Lost total control, my throttle fail safe was set for
19 % , but she went in a full throttle. I use the little
boxes for my connections ( battery and ailerons) to
help ? prevent them from comming unplugged.

Bob

Charlie P.

Switch failure?

DavidAgar

My Feedback: (108)

You don't mention what brand of radio or servo models you are using. Some servos are not designed for use with NMHI batteries. Just a thought, Dave

Gray Beard

My Feedback: (-1)

The answer to the question is: Most of them!!!!! Most of the crashes I have seen in the last couple of years are brown out problems with the 2.4 but that has gotten a lot better these days. Most Spectrum users have gone over to 6volts and it really has helped. Some things just remain a mystery forever.

jester_s1

Sounds like a switch failure to me too. Either that or your flight battery is no good and dropped too much voltage under load.

TFF

I bet 50% are unsolved because most are not objective when looking at the problems; we try but we still assume. I have also seen 3 2.4 radios go into a fail safe in the last couple of weeks; one ended in a crash. Two different brands of radios. I think the advanced technology requires more perfection when installing over old stuff; the old stuff was more suspect to interference inside the plane, and the new stuff you must have antenna perfection. The new radios are also not hobbiest friendly; you use to have the radio guys in the club who had the test equipment to really test stuff, now it all goes back with good faith that it will work when returned. It is one of the things we are going to regret down the road, not controlling the technology we use.

Johnkpap

My last unsolved crash I suspect was a "New Switch"[] all the other radio bits including the RX and servos
were from a Worn Out model that had not crashed, I bought the new switch for my scratch build Kaos 60 and on flight 6 .....No radio at all !!!

On evaluation of the Wreck the batt pack and RX were fine .... the "New" switch was Smashed in the crash so I will never Know...[]

The next model .....Jensen Ugly Stick..... has a old used swtch .....No Problem over 50 flights and counting.


Don't use a cheap new switch in a nice new model.....use a grotty old one...It may be more relable



Johnkpap

dignlivn

Thanks for all the input guys.


I was using a HD switch, the plane was in it's
3rd year of flying. Also the radio is a Futaba 6ex 2.4
with Futaba servos. This has been reliable system for
many flights. I know I will never really find the cause,
so now I'm not sure I trust the Tx with my other plane.

Thanks again,

Bob

Steve Percifield

My Feedback: (14)

Since you had fail safe set and you said the plane went wide open, would tell me the radio was still linked/functioning, otherwise, failsafe would have activated....as long as battery power was still there.

I think one of comments about is very appropriate. It seems today the general thought is that these new radios are bullet proof. I see very sloppy radio installations now. NO ONE uses any kind of vibration protection any more, including the battery pack. Everything is just taped to the structure somewhere. Common prctice was to wrap the batteries and receiver in foam and we were careful how they were placed in the fuse. I know the 2.4 receivers don't have crystals and pots to protect from vibration, but they are still soldered together and are still fragile, but every one just glues they somewhere, now. 2.4 is still an RF link, but, again, everyone thinks interference went away. I know it takes more now, but that link can still be broken. I know it;s tougher and very rare, I'm not going to debate it, but it can still happen. And why do we think we can fly 100 airplanes at once when there are only 80, 2.4 gig freq's?? I think we need to get back to some common sense basics.


Dignlivn, I'm not hammering you, I'm sorry for your loss......just had to jump up on the soap box..

steve

dignlivn

Thanks Steve,



My Rx was mounted on foam, the battery was
wrapped in foam as was the fuel tank. I agree
the fail safe never kick in. There was one other
plane in the air at the time, he was using the same
Tx as mine. Just another factor involved, he landed safely.

Bob

Steve Percifield

My Feedback: (14)

Bob,

Sure does look like you were doing everything right. I think sometimes the airplane God, just says it's time.

steve

dignlivn

Yeah, it had reached it's expiration date,
I guess,

Bob

Charlie P.

I've noticed that. I just switcned from a 10 year old 72mHz to 2.4gHz in my old Contender and it had a "radio box" with lid built in for the receiver. The new receives is 1/4 the size of the old one! I stuffed it in the same box and filled the difference with foam rubber. It could now survive a sledge hamme rattack . . . the receiver, anyway.

At the airfield and in magazines I see a LOT of receivers, batteries, tanks, etc. just Velcroed directly to frames and fuselage plates. I still wrap foam rubber on the contact points. Old habits. Vibration kills, as does sudden impact.

dignlivn

FWIW

After a week of playing NTSB, my findings are,

1. Battery may have come loose from harness ? (even inside the box which is supose to prevent this)

2. Three year old switch may have failed ?


For the Fail Safe to operate, it requires battery power onboard.


Bob

frets24

My Feedback: (15)

I lost one not too long ago due to the battery to sw harness connector failing. I had just recently changed all the other connectors from the old futaba style to the new type as well...just didn't do that one[:@] Checking it after the crash revealed that it did not make good contact if pushed all the way in, good if pulled slightly apart (1/4) and then no good at halfway apart and out.

It was a pretty spectacular crash though. Got to the top of a loop and went to throttle back for the descent...no response, full throttle from there straight down into the ground. Never heard an Os .46 rev so high! Fortunatly( and unbelievably) everything survived except the airframe. I had really enjoyed that one for over 15 years.[] Kit is NLA so I'm just finishing a scratch build to replace it. Hal Davis/Hobby Dynamics Sportee Fourtee

Before and after. The red connector in the center of the fuselage shot was my sabotuer!

dignlivn

frets24



i bet the red connector is 22 gauge wire ??

I was 150 ft. up showing how a stik could hover ( shortly) . I
kicked in rudder for a hammer head turn and.

Thanks for sharing, 24 frets, you must play Gibsons ?

Bob

frets24

My Feedback: (15)

Used to be refering to a 24 fret Rickenbackr hollow body, a la Tom Petty circa "D#mn the Torpedos"... now I have teenagers so it's more like "frets(worries) 24/7" but, yes my Gibson LP custom is my fave axe....though any stringed instrument is fair game!!

The connector in ? was OEM Futaba old style 90* (J?) connector from the mid 80's, and yes it's a 22g harness. Never been a problem in a 4 servo plane, I go to 18g harness and bat leads for 6V and 6+ servo planes.