Jump to content

The demise of my Ceres f3f


GuyB
 Share

Recommended Posts

George Young

Gutted for you. ☹️

Losing contact on the landing approach would suggest to me that it is indeed a battery problem. I am assuming you were deploying the crow-brakes when you lost signal? Crow-brakes do take much more power than general flying and put a big load on the battery. Exactly that happened to me with my Precision but fortunately my Futaba went into failsafe and I got away with it and managed a hasty landing. One dodgy cell in the Intelect 2/3 AA pack. (I don’t use them any more!)

 

  • Like 3
Link to comment
Share on other sites

Could have been a battery or rx problem, could have been a power lead problem from repeatedly flexing it plugging in to the rx. Anyhow - after a big crash the battery & rx should go straight in the bin !

I've had 1x major smash-up due to 2.4 lock- out. I blame a dodgy FrSky rx that came used with another plane  - but of course the previous flight was faultless. Battery & what was left of the rx went in the bin. Voltij pieces now back together again.

Phil.

 

Link to comment
Share on other sites

7 hours ago, George Young said:

Gutted for you. ☹️

Losing contact on the landing approach would suggest to me that it is indeed a battery problem. I am assuming you were deploying the crow-brakes when you lost signal? Crow-brakes do take much more power than general flying and put a big load on the battery. Exactly that happened to me with my Precision but fortunately my Futaba went into failsafe and I got away with it and managed a hasty landing. One dodgy cell in the Intelect 2/3 AA pack. (I don’t use them any more!)

 

Hi

lost control slightly before landing but based on all the comments here it does now look more likely to be a battery issue

Guy 

Link to comment
Share on other sites

Hi Guy

As always, George makes a good point here, if you had a failsafe, why didn't that stop the incident before it started?

If you went in vertically from 250 feet you obviously weren't on the landing approach, but were, possibly, just deploying the CROW

Was your Rx set and failsafe enabled before that flight? and what was your failsafe set to do? Usually, it's set to deploy the brakes, which points potentially to a sudden and complete loss of battery power at that point

Also, I remember these Intellect 2/3 inline AA batteries being the focus of several complaints a while ago, and the suggestion not to use them was made by several flyers.......do you remember seeing those comments? 

I remember when "my" charging routine detected a potential battery failure and that battery was in the bin within minutes......I'll never know whether this prevented my experiencing what you have, but it certainly didn't hurt......

If nothing else, I'll bet quite a few people did some safety checks to be sure they didn't suffer the pain of loss you have so, hopefully airing the problem here probably did do some good......let's hope you can have that consolation......I really hope you can

Regards

Pete

BARCS1702

  • Like 1
Link to comment
Share on other sites

unfortunately you are never going to find out what went wrong. I had an fs3 pile in while flying f3b, say from 200m straight down. Now everything still worked including the switch, battery and RX (Even though the case was damaged and one aerial was pulled out in the detonation).  The wiring seemed fine also.

2/3a batteries are poor but I and half the forum have certainly done a lot of flights with them down the years without trouble.  In the future I would look at 18650 cells, as they are better in every way, except perhaps size. With the caveat that there are a lot of fakes around on ebay (I buy from fogstar).

Really unless you have some sort of data logging, which hitec doesn't have, it's likely to remain a painful mystery. 

Guy - the only bit of the aerial that counts is white tip and the end bit with the BODA antenna on it. The rest of the length of the aerial doesn't do anything. 

Link to comment
Share on other sites

Just regarding Hitec and the Aurora 9, I've been using them since time began.  They are known for their very healthy link, and I can only concur.  Only the 9 channel Rx has 2 aerials: the rest have one, but really don't need more than that. 

Link to comment
Share on other sites

4 minutes ago, Andy_B said:

did we ever complain about just one aerial on 35 ..? 

35Mhz is a 8.5m wavelength, 2.4GHz is 12cm. It makes a difference.

Steve

Link to comment
Share on other sites

I've been reading this thread with interest as three weeks ago I lost my Vikos in similar circumstances. Woodstock may be interested to hear that the Vikos was the sister to the one that I sold to him many years ago. Sad as it always is to lose a nice model the Vikos had added sentimental value as it belonged to my sadly departed pal, Tim Shaw. We both ordered the models at the same time from T9. I acquired the model from his estate and spent quite a bit of time sorting out the nose area that Tim had tried to rearrange with one of his infamous landings!

The Vikos had flown perfectly on many previous occasions with no issues at all. The newish 6v 2/3A Nimh pack had been peak charged so I knew that was fine. No switch used as I plug directly into a short flylead connected to the receiver. The receiver was a Spektrum with two antenna exiting through the glass 2.4 friendly nose.

After a 15 minute flight the lift was getting a bit patchy so I decided to begin my landing approach but still high over the slope. (No crow used) Suddenly the model stopped responding and it did that well known hideous roll onto its back at which point it started to dive at full speed into the ground. the sickening sound told me that it had not hit anything soft. Arriving at the crash scene confirmed that the Vikos had dived straight into the middle of hard bridleway and the model was totally destroyed.

When I got home I checked all the components that had survived. Four of the servos still worked with the others badly broken. The receiver battery, despite now rather crumpled still worked fine. The receiver however was totally dead. Of course it had been involved in a high speed impact so that could well have caused this. The transmitter is fine and I've flown several models using it since.

Taking everything into account I'm pretty convinced that the receiver failed mid flight although I'll obviously never be able to prove that.

I did contact Horizon Hobby about the incident and they asked me to send the receiver back to them in Germany. Today I received a box from HH with my broken receiver and a form that said "the receiver is irreparably damaged. A repair is uneconomical or not possible." Not that I already knew that. I am not impressed with that reply and I've emailed HH telling them that.

When you've been flying model aircraft as long as I have you do tend to be quite philosophical about losing a model but on this occasion and because of the history of the model it meant quite a bit more than 'just another model'

Anyway, I thought I'd share my loss with you and although I'm not sure it will, but if it helps anyone else then it has to be worthwhile.

  • Sad 1
Link to comment
Share on other sites

Hi Dave

Reading your post, it was a very similar incident to mine aside from the sentimental aspect of your model. 

My receiver was ok and from reading all the other posts it now feels more like a battery issue. Like you I have enjoyed this hobby for  a number of years. In fact tonight I escaped father duties and had a fantastic hour on my local slope in an 8 mph westerly flying a 20 year old Whisper 2m

the good news is that I get to replace the Ceres! 

Guy 

 

Link to comment
Share on other sites

Please check each cell of the battery individually under load.  A simple static voltage check will not find low capacity or a cell with a high internal resistance.  If all OK, charge it on a delta peak charger and then discharge to measure capacity.  

Link to comment
Share on other sites

On ‎21‎/‎08‎/‎2018 at 12:02, Andy_B said:

did we ever complain about just one aerial on 35 ..? remember when a 400mah battery was big ..........

I remember when a 400mah battery was a 4 cell DEAC which was centre tapped and one half drove servos in one direction and the other half drove them in the other direction which is why the servos were 4 wire, still have the radio gear upstairs (Swan/Stavely)  🙂

I also have had problems with 2/3 cells and never recommend them to either flyers or even sailors  😉

Link to comment
Share on other sites

I damaged  an f5b with signal loss.

It was using a small lipo  for the rx  with a Voltage regulator.

I think under load the rx pack dropped, the VR shut down until voltage restored.

Thinking it was a range issue I managed to get it back to the field, and then used the crow. Major error!

It slowly rolled into the ground, crunched the nose, shorted out the esc and caught fire! Not irreparably damaged but has been collecting dust for 2 years now!

Link to comment
Share on other sites

What ever the battery type or size remember it is a storage device and you can only get out what you put in. (Which is usually less than that claimed on the label).  Whilst charging, even with a modestly priced charger it is possible, nay, desirable to note this figure.  You can then relate this figure to the amount of flying you have done that day and after a few flying sessions you will be aware of the patterns, or most importantly when they change and something is wrong. A real example: I had four flights totalling about two hours on the sticks and I returned 850mAh into my receiver pack which is a 2200mAh LiFe. Let's say half! This leaves enough contingency. I am confident I could (maybe next time) have six flights. When results trigger a doubt then use the charger to discharge down to the minimum voltage (for your battery type/no of cells - normally found in the charger instructions) then recharge to capacity and note same. It should be near to the manufacturer's claim. (use currents close to those in the experiment below for realistic results).  Occasionally, by discharging note the remaining capacity when you return from a day's flying to check your contingency and ensure confidence is well founded. 

Using a watt meter, which most of us now own for measuring electric motor current/prop/battery combinations, it is a simple matter to couple it between your battery and Rx, waggle all your sticks, or apply full crow 'till she buzzes, and note the maximum current draw (and voltage drop) I use this method with new gliders to get a handle on battery capacity requirements, or put another way; how long can I fly with the battery which fits into that tiny space in the nose? It is very conservative, since most of the flight won't be under these high load conditions. Treat this as contingency.

I'm not suggesting an onerous technical programme but a simple routine to manage batteries without total reliance on the battery checker.

It is possible for automatic (smart!!!) delta peak chargers to mistake the number of cells attached for charging and thus finish prematurely. If the charger clicks off in too short a time based on your experience from previous charges then something is wrong. Since capacity is a function of charging time this is the same strategy as outlined above without actual measurements.

I apologise if this sounds like preaching, but I see too many instances of total reliance on battery checkers.

Happy flying,

John

Link to comment
Share on other sites

Another simple check when using Nimhs is to actually feel how warm they are. If the charger has  automatically cut out and the pack is still cool then I would have suspicions and double check that everything is okay.

Note - If the pack is hot after charging then that suggests overcharging which is also not good.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.