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a report from Tore 

Yesterday , Saturday 24th March, we at last got that sunny weather without any wind at all, very handy for the park-flier and electric-flier meeting that Rune Olsson from Lidingö Model Club arranged at Elfvik, on the most northern point of Lidingö. Lidingö is a sort of satellite town of Stockholm, both situated in the archipelago looking out on the Baltic Sea. This was the fist outing of this year for me and my R/C partner Rune Molén as neither of us functions well in cold weather. When we got there, about 15 cars were parked at the side of the field, so we guessed that about 25 fliers had attended. 

Rune Olsson, the host (pictured right), is a well-known El R/C specialist, who we find on the prize stand at most El competitions in Sweden. He gave ample advice to us less-knowing el-fliers.

Esbjörn Forslund arrived later on and flew a twin-engined grey foam model. We wondered if this model with its tiny propellers would fly. Fly it did in a spectacular way! It executed loops with a very small radius as if it aimed to bite itself in the tail.

Philip Thulin visited us without a model, as he had burnt his esc in a crash. For sure he will install a fuse next time. Eventually he nursed Johan's four-years old son Max, while his father Johan B. flew. Quite a task - Philip had to accompany wild Max who was throwing foam fliers all around him. This one has got the gift!

El pylons - ammo for Max!

Johan Bjurling had a hoard of models with him. Our mouths watered, when we saw him starting a tiny 35 inch Crazy Sparrow (left) from the not-so-golf-like turf. It flew very well and could manage fine rolls as it had aileron as well as rudder and elevator control. It had a severe glitch, from which Johan managed to successfully land the model. He then changed receiver and immediately got in the air again, doing a marvellous flight, which was applauded by all. He also flew his very agile Terry imported from Graupner. Both these models can be seen on Johan's site www.mft.nu which was featured on the site seeing page of ModelFlight  #30.

Rune Molén test-flew his beautiful ARF model Miss Europa of Italian make. A very beautiful model with an old-timer look, with transparent purple covering on the fuse and ditto yellow on the wings. It flew in a very stable manner and Rune decided on the spot that electric RC flying would be his future. Amen!

Tore Loodin tried to get the little Scorpion airborne. After a mighty heave from Esbjörn Forslund it immediately made a loop and tried to sting us in the bottoms. I will cyanolite the motor bulkhead back and go on with the trials. Tore's trusty el sail-plane "Robin Wood" broke its carbon fibre tube aft end on the landing, so he will construct a new conservative wood fuselage to the wings.

Thank you Bengt Larsson and Leif Svensson who have provided the pictures.

Bengt Larsson's Bleriot

I have just had to replace my 12volt 7-amp hour sealed lead acid battery that is installed in my flight box and is used, via the power panel, to power my starter; it also has outputs for a glow starter. The reason for replacement was that, despite having charged the battery up, it would only turn the starter over for a few moments before the power faded to a point where there was insufficient power to turn the engine over against compression and the starter just ground to a halt.

I use a Simprop Multicharger for charging the 12 volt battery, using the nominal 500mA output which, according to the manual, has a maximum true output of 317 mA when charging a battery of 12V/10 cells. As far as I can determine, of those available on the charger (the others being nominal outputs of 50, 60, 140 and 180 mA), this is the correct output to use for the lead acid battery

I do not know if the failure of my old battery is down to anything I have been up to - I usually put it on charge for 12 - 16 hours when the needle on the dial of my power panel gets down to about half way, and it has performed all right for normal use over the last three years. 

Can anyone help, please, with answers to several questions as I start to use the new battery (with which there were absolutely no manufacturers instructions)? 

• Is it likely the old battery has failed simply because of its age and use to date?
• What is the correct procedure to follow before I use the new battery? Do I give it a full 16-hour charge as usually recommended for new nicads, or is it a different requirement for a lead acid battery?
• What on-going charging procedure should I follow?

The Simprop manual states, "Lead-acid batteries should only be charged at the nominal charging current when using constant current. [What does that mean?]. The charging time should be kept to absolutely. Too long a charging time leads to gassing the battery! The charge still in the battery at the start of charging must at all events be taken into account when calculating the charging time.

"For example: a battery has a charge of 30% remaining => the charging time is reduced by 30%. If overcharging occurs the electrolyte of the battery dries out. With older type car batteries the loss of electrolyte can, as a rule, be made up by distilled water. With maintenance free lead batteries this is no longer possible. Gassing is to be avoided at all costs, not only as dangerous gases are released but also because the lifetime and capacity of the battery are substantially reduced."

• If I am to follow those instructions for recharging, how can I determine what percentage of charge is remaining before proceeding? 
• Is there any way to determine that the full charge has been reachedor is it a question of timing?

Any advice - in simple language for one who just can't seem to grasp this subject - will be very welcome. 

Reg.