retirement time
 

<div id="post_message_16008790">Not the hobby just the plane. After three weeks of patching, glueing, and recovering my hog bipe (from a mishap with the elevator control horn), I finally got her back up in the air and it flew beutifully. I just finished my fourth flight with it and decided to go up one last time. I checked the rx battery, fine. Checked my radio battery (has a voltage needle on top), showed 90%. Ok, here we go.

I get it up in the air, and after about 2 maybe 3 minutes into the flight, my engine suddenly went to idle. I tried to throttle up, nothing. I realized I had a problem and needed to get it back on the ground. I turned to come back to the runway. during the turn, I noticed that as Im putting in control inputs, the plane is getting slower and slower about responding. I finally get lined up, the engine dies; my first deadstick. http://www.rcuniverse.com/forum/js/f...bout_smile.gif
Heres where I get in trouble. At the end of my runway, unfortunately there are power line crossing it. I see them and as I am trying to go under, I get no reaction from the plane, NO CONTROL at allhttp://www.rcuniverse.com/forum/js/f.../omg_smile.gif. I hit the lines with the gear. The tail flips straight up and straight to the ground it goes. The engine is now where the cockpit should be.

After I got my head back I looked at my radio and the meter was on about 5% battery. So did I fly too long or is something wrong with the batt or radio? Ive never flown that long at one time with just one radio so I dont know how long the batt should stay up but I would think longer than that. By the way, this is the third major repair on the hog so I think its time for retirement. All of which, Im proud to say not my fault (not from flying anyway, just skipped maintenance. Lesson learned.) http://www.rcuniverse.com/forum/js/f...ssed_smile.gif</div>

RE: retirement time
 

Most basic radios can get at least an hour of on time on a full charge using the stock battery. So you should have been fine, especially if the meter said 90%. It sounds like a bad battery or corroded connectors. I would at least cycle the battery before using it again and clean the connectors in the radio.

RE: retirement time
 

+1,
I would definatly take a hard look at that battery, Falling from 90% to 5% in 2-3 minutes is not normal, I'm guessing that is the stock NiCd battery that came with the radio. If you never ran it down past that point (or cycled it) before it may have deveploed a memory issue and once it got low, just dropped off the map.

I'm curious, How old it the Tx battery?

RE: retirement time
 

You guys are teling me exactly what I had in mind. As far as the age of the battery, I assume its as old as the radio, probably at least 5 yrs old. The radio was given to me so I dont exactly know. Its a tower 6channel with the tower batt. I do believe that we all are on the same page though.Thanx for the replies.

RE: retirement time
 

I have watched my transmitter voltage drop from 10.8 down to 9.5 in a matter of 30 seconds. I just happened to catch it as I was about to taxi out with my corsair. That was also an old battery. I do no more than 3 years on my batteries. Lost too many planes to battery failures and I accept that as pilot error. It pays to do regular battery maintenance. Out of 5 this year, I had two cycle at less than %70, out they went.
Edwin

RE: retirement time
 

I just purchased one of these

http://www.hobbycity.com/hobbycity/s...er_Lipoly_Pack

on the advice of several of my friends at the club after I noticed my TX voltage dropping much faster than normal. If you already have the Lipo chargers and such then it is easy to use. I just used it for the first time last weekend, and It worked great. The others guys who turned me on to them say they only have to charge thier radios once a month or so. Make sure and set a low voltage alarm on your transmitter if you have one to keep from discharging too low. If you dont have a computer radio just check the voltage regularly and dont discharge too far.

RE: retirement time
 

I went to lipo in my Tx this year too,, it's a great upgrade, don't know why I waited,, well I do know, I didn't need a new pack yet.
Charging it once a month depends on how much use,, but that's about average for me too.

I got this one http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6955&Product_Name=ZIPPY_ Flightmax_2500mAh_Transmitter_Pack_(Futaba/JR)

RE: retirement time
 

Can that voltage of 11 v be used directly in a Tx?

RE: retirement time
 

All great responses. I will consider the Lipos, but first a couple of questions. I assume I will need a new charger, right? Ive heard you need to use a special bag to charge them in. Why? And lastly, how do the costs measure up to conventional batts? Thanx again.

RE: retirement time
 

Yes you need a lipo charger,
Spontaneous combustion used to be a problem, With current line of "Balanced" chargers it's not a big issue any more.
But they always have that risk, just not a likely as in the past.

I still charge mine where I can watch them or in an area where if it did go up, nothing else would catch fire,,
If I charge them indoors it's on a ceramic dessert plate (don't tell me wife)

RE: retirement time
 

Almost sounds scary, but as you said, Im sure improvements have been made. This is just all new to me. I got al of my stuff from a guy and all he basicly told me was good luck and have fun. He did tell me what some of the stuff was but nothing about this. Ive pretty much been doing everything on my own since the very beginning. Thanx alot!!

RE: retirement time
 

Some people will disagree, but I never use batteries older than two years. I always date them when they arrive. If the battery is installed where I can't see it, I put a label inside the plane with purchase/install date. Heaven knows how long they sat around prior to the sale to me. After two years, they are used for something other than airplanes.

RE: retirement time
 

You're right, someone will disagree, me.

If you have a good preventive maintenance plan in effect, you will not have any trouble with charging issues. I keep a log of all Tx and Rx batteries in my aircraft and note the peak voltage at the end of a charge. I use a couple of Triton chargers which allows me to access that info. By doing this, I can see when a pack starts to deteriorate to a lower charge level. If it is a Nicd I will perform a discharge under load to see how many minutes it will last, down to 1.1 volt per cell. If unsatisfactory, I scrap the pack after an effort to cycle that does not bring the pack back to a comfortable level.

It may seem like a lot of trouble, but it saves aircraft. I have enough trouble with dumb thumbs without adding dead batteries to it. You should also have a meter that produces a load for checking your batteries at the field before flying. Anything suspect should keep you grounded.

Bob

RE: retirement time
 

I'll use NiCds until they start dropping on the cycler. With 6 volts if I have that oh so rare instant dead cell it won't crash me.

Spontaneous lipo fires are practically a thing of the past. They can still happen yes, but with a balance charger using an appropriate rate on a pack in good condition there is no danger. Lipos will get hot and puff before bursting into flames, so if you're paying attention you won't burn your house down.

RE: retirement time
 

Thanx guys. Looks like Ive got alot to think about. The Lipos are looking like the way to go. Now I just gotta figure out all of this "cycling" stuff. Im sure its all simple, just have never done it before.

RE: retirement time
 

Cycling only pertains to Nicds. The other chemistries do not have a memory effect.

If you store LiPo's, you want to keep them around a 50% charge state. They will last longer that way. I use a Cellpro 4s for my smaller Lipo's which shows the state of charge on it's screen.

Bob

RE: retirement time
 

Thanx for explaining. So its not as bad as I thought. Seems like Ive got the more problematic batts already. Life might just get a little easier

RE: retirement time
 

retransit, your method works great and is reliable. However, most fliers are not as dedicated to battery maintenance. I totally agree that a program like you use will get several more years from most battery packs:):)

RE: retirement time
 

Another thing that kiils batteries is sitting around unused for long periods of time,, I took about 5 years off from flying, was racing r/c cars/trucks, all my aircraft NiCd batteries were junk from sitting,,, sounds like abaser may have gotten a hand me down that sat around a while too. These things charge up, but they peak early and fall off fast,, even after cycling the packs a few times, they just didn't have the capacity,,, they all went into the Haz-mat recycle can.

abaser, and any one else reading
A good charger that cycles and discharges with a digital readout is a wise investment, test those packs on the bench,, not in the air
Best $100 I ever spent on this hobby.

good luck

RE: retirement time
 

Yeah, it's not for everyone. As with most things in life, there is a level of dedication for everything. I have my limits also.

A couple of years ago I was taking some video at our field. A member had a throttle stuck wide open and proceeded to run out the tank. When I went back and watched the video from the beginning I caught some background comments by the pilot saying that his Rx battery's state of charge was less than adequate for a safe flight. The result can be seen here:

http://www.youtube.com/watch?v=DlxfWTE1HIU

RE: retirement time
 

hi
to many people in this hobby think that a good ESV VOLTAGE READING means a good battery ,you must cycle NICADS AND NIMH batterires to determine the MILLIAMP CAPACITY OF THE BATTERY to know the batteries true condition-NICADS and NIMH batteries will give you a 5.5 volt reading on an ESV ,-when 20% of the batteries capacity is gone ,at a loss of 20% of your battery -you are subject to internal battery shorting ,-that will take out a cell or worse-do go to : RADICALRC.com ,some of the best info on battery care you will find- ,if you fly with NICADS OR NIMH___YOU MUST INVEST IN A CYCLER__ the ace hobby DIGIPACE has been my best tool for this for 20 years , charge the batteries above over night SLOW__discharge with a DIGIPACE every 3 months if flying the same plane or when you fly a plane you have not used for some time ,-top off NICADS every month or two if idle- they will not short out if kept charged to full ,YOU WILL HAVE NO PROBLEM WITH YOUR BATTERYS as that is proper care and maintenence of the above type batteries- no battery issues in 20 years ,still fly with NICADS ( 40 to 1/4 scale glo stuff ,no electrics ) if it aint broke dont fix it ,NICADS are all there was when i started in the hobby ,they never let me down ENJOY BEST REGARDS TONY

RE: retirement time
 

NiMh batteries do not generate a memory, as Nicd's do. Initially, NiMh batteries must be seasoned, that is to say deep cycled, so their potentional capacity can be realized. If you keep short cycling NiCd's you will induce a memory giving your battery a short run.

I have a Digipace that I bought may years ago and it served me well but today's version of battery cyclers runs rings around it, due to their ability to cycle large capacity batteries of different chemistries.

As I stated previously, you must use a meter that produces a load in order to check the state of charge. It's OK at the field, but to know its true capacity, you must use a cycler, which is impractical at the field. If you did your homework before going to the field, you can feel safe with your batteries.

Bob

RE: retirement time
 

again you guys are right. I talked to the origional owner this afternoon and got a shock. ALLof the stuff he gave me was at least 12 yrs old. Batts included. The radio was in such good shape, I assumed that it was a whole lot newer than that. No doubt in my mind now what caused all of my misery. I cant believe that the thing even works. Just out of curiosity, I charged the radio over night last night. This morning I turned it on, 100% on meter. I reckecked it every 5 minutes just to see how long it would take to discharge. Somewhere between 45 and 50 minutes, it went from around 85% to 0%. Problem solved, lesson lesrned, and decision made to replace not only the batts, but radio too. Been looking for an excuse to go 2.4! Only problem now is which one , and man extra rx's seem to be a little pricey. Oh well, just have to do one at a time.

Thanx for all the help though. Ive learned a lot and realized that there is a lot for me to still learn. Good luck and happy flying to all of you!!!

RE: retirement time
 

I have a Futaba 9C Super with a 2.4 GHz module but sure would like to have a Hitec Aurora 2.4. I can't justify the cost of changing everything over. I'll stand pat for now.

Bob

RE: retirement time
 

If you want to move to 2.4, that's a fine reason, to retire it, but I wouldn't be so quick to throw the baby out with the bathwater.
The raidio I use, Futaba 8uaf, is near 10 years old and still functions just fine with the new battey I bought this year, I have a 15 year old 7UGFS (glider radio) that works perfectly fine too, I use it as a spare and a buddy box.


p.s.
Those "Tower" radio systems were built by Futaba,, they're just as good just with a Tower sticker. The old "Cirrus" line Hobby People sold were made by Futaba too