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Hi All, Here are a couple of photos taken at our club field taken at the same time as the above previous ones, the Sunderland and my own design Stirling have now been published in this months RCM&E I did toy with making a tractor too Yet to be maidened, but hope to, when work and home life allow. That's all for now Regards Robert

Well it's been a while but I'm near the end of this build, just need to paint the cowling and install the radio and hook up all the controls

Drill, car and most consumer batteries use Lithium Ion batteries as opposed to the Lithium Polymer batteries in RC Models. There is plenty of information about the differences readily available but the Li-Ion batteries will not tolerate the current draw demanded of LiPos. RC Models must be amongst the most demanding application for batteries anywhere. Who else discharges their batteries in 3-10 minutes as a matter of course? Typically the cycle time of batteries in other applications approaches or exceeds hours, so the batteries have a much easier time and last longer. The typical electric car has a 60KwH battery. To discharge it in 5 mins, like we do our models, the motor will need to be producing about 1000 horsepower throughout that time. Conversely if you want a longer life for the battery in your EFlite Cub then only run it at 1-2 amps. Of course the model would not move but the battery won't puff and will last 10 years😀.

Well, as promised, here is the video from today's flight which, I hasten to add didn't go according to plan. To cut a long story short, I was finding it difficult to control on elevator in fact even on high rates I didn't have enough throw. Similarly the engine started to misbehave in flight which I put down to a bad tune. The landing was a bit of a disaster due to a lack of both elevator and rudder control, well there was some but no enough and not when I wanted it, as you will see. Anyway the damage is only very slight, prop damaged (not broken) and both wheel axles bent. As you will see from the video it also has a tendency to climb under throttle so that needs fixing! On closer inspection I found that the servo tray which holds the Elevator, Rudder and Throttle servos had come loose (it wasn't glued in place, it was screwed!!!!) which meant that the pull pull tension for both Elevator and Rudder was somewhat missing and relied on the push rod for the servo and that of the tailwheel steering to hold everything in place, or not. The good thing is that the C of G is correct and the 200 in-line has more than enough power. The video is uncut, apart from me cutting out the swearing at the end!!

I haven't measured the current drain on our systems so I can't really comment with authority. I've converted our ordinary bikes with a FWD motor in the hub with the battery carried in a special rear pannier frame with an LCD display/controller on the 'bars. I'm sure both the motor and the esc are well under stressed. In fact IIRC (it's while since I set them up) the power rating is adjustable but as the 250 watts setting is more than enough, I'm happy with that. I still like to feel I'm working when riding though my days of thinking a 100 (160km) mile ride is no big deal are long gone 🙂 I wish one of the display options was current draw but it's not. In any case I think Remco Evenpoel would be quite capable of dropping me on a climb even with my electric help - but I'm 60 years older than him.

Our electrically assisted bikes have 10S Li-Ion batteries (40ish volts), which means, at the maximum legally power output of 250 watts, the motor draws about 6 amps. Not very demanding in aeromodelling terms. Plus we almost never use full power except for a bit of fun on the last climb up to our house. There are 5 levels of assistance on the system I've installed and I tend to think level 1 just compensates for the extra weight 🙂 We've been using the same 7 cell subC NmH 3000 mAh in our bathroom radio for about 10 years and it still recharges to its full capacity with a 2 amp charge. I don't know the current draw but the radio was originally designed as a mains/battery unit with 6 D cells primary cells (very expensive) until I modified it to take the 7 cell sub Cs so, as they're slightly under voltage, it's not much. So using batteries with modest current certainly makes them last a lot longer and pushing them the way we do in models is the main reason they're both expensive and have limited life.

Having had to jump out of the way on a regular basis in car parks when blind homicidal maniacs reverse out of spaces without looking, over the years, a bleep to warn, “en garde”, is good.

@leccyflyertotally agree with you there. My experience has been "the more expensive they are, the shorter the lifespan". Maybe they expect to be treated better. But I also keep getting told that ASP, Magnum, SC engines are 'useless', but I have examples pf each that are many years old and run beautifully....... maybe cheap and I suit each other. 🙂

Ok, I’ve put the new plugs in. OS number 8. I’ve also placed the engines sideways. And put the tanks in their original place. The engines are running much more consistently. There is still more work to do. I’m thinking of placing PTFE tape around all the needle threads to stop air leaking in. Video posted now as promised

Looks a bit better now.

If there was ever an arena where that old adage is blown out of the water it is in the arena of Lipo batteries. The best lipos I've had were the Loong Max packs, marketed by Giant Cod and confirmed as representing super value for money in the BMFA tests at the time. The worst lipos I've ever had were the extortionately overpriced Flightpower packs which were amongst the first lipos to be widely (over)marketed at about the same time. They were more than 3x the cost of Loong Max at about 80 quid for a 3s1p3000mah pack. I like to tell the story of a very experienced electric flyer who, when I told him there was a half-price Flightpower sale, after the overhype had been seen through - "Don't you mean a Half-Power Flightprice sale?" 😄

If you're using releases, be sure to check the C of G with and without them. My F100 can only have some of its armament on for static display because of the huge shift!

Taking me a ridiculous amount of time, but's starting to look like a plane. The wing shape is really beautiful.

For sure, on the airframes and bigger parts, it's definitely so-able. For smaller parts like that tailplane bellcrank, I'd be really tempted to try and make a 3d printed compression mould, and mould it from carbon.

So now a 'no effort' on internet and a 3 day delivery date, beats cutting out a bit of epoxy.😅

Well here it is. "Hound Dog" 50" span, about 4 lbs weight. It flies very nicely and is aerobatic (Not much point if it isn't aerobatic!!)