During the recent RAFMAA committee meeting, it was agreed that we as a committee should look into the ever increasingly popular form of modelling, known as Indoor R/C, as a possible addition to the events calendar. My personal interest in this discipline was reinforced when I saw the Rt hon. Geoff Ellis Esq. at the indoor meet held at RAF Digby in November of 2004.

He was effortlessly prop hanging his foamie factory design just inches from the RAF Digby Gymnasium sign hanging from the ceiling!! I had to have one!!!

My main concerns for this project were going to be power, weight and overall set-up cost. After much research into the project, I estimated that the flying weight limit had to be between 200-250g. Doesn’t sound very much eh!!!

As Christmas was approaching, I put the ‘wife’ feelers out with regards to dropping hints and started busily scanning my latest copies of RCM&E, Model World and the likes for the best deals available.

For the airframe, it was a case of  ‘Christmas desire’ that made me choose an Ikarus Extra 330 shock flyer, as I wanted to minimise the construction time. I  must point out that there is also the option to download the freebie plan from Foamiefactory.com, which is, may I add, an excellent design as well.

As far as kitting it out, I was advised to fit the extremely small GWS 4 channel Pico RX (around £15) on the advice of some fellow ‘shocky’ fliers, as it is compact and lightweight. More hint dropping needed me thinks!!!

Having read the article in the recent RAFMAA newsletter on the CD Rom motor, I decided that this unit, supplied with Li Po power was to be my chosen workhorse configuration.I decided to get in contact with a company called www.Robotbirds.com. The chap I spoke with there (Andy) was extremely helpful.  I basically told him that I was new to shock flying and electric flying in general, and hence, didn’t have a clue what to buy. I’m a Petrol head you see.

He took me throughout the set-up required and after some 20 minutes on the phone, my credit card got a gentle ‘seeing to’ and the parts were despatched the next day!!!!

I ordered the Cd Rom brushless motor, a Castle Creations Phoenix 10 speed controller, a 2S 7.4v 340mah Li-Po battery pack and all the necessary connectors and fittings. Total cost around £85.00.

Warning! Warning! Warning!

When dealing with LiPo batteries there are a few pros and con’s to consider.

Pro’s

They are extremely lightweight and compact compared to their Nicad or NimH brethrens making them perfect for the job in hand.

Con’s

As the enclosed safety leaflet from the pack says “DO NOT  overcharge, over

discharge, pierce, damage, attempt to reconstruct, attempt to charge with an incorrect charger, charge in models, charge in the car, charge indoors” etc.

Blimey!!! Mini bombs by the sound of it!!!!

Also they don’t like (understatement) being discharged to anything less than 3v.

So beware!!

Fear not. As long as you use a LiPo / Li ion specific charger (starting around £15) and set it to the correct cell setting you shouldn’t have any probs. To get around this potential problem of over discharging the cells I opted for the Castle Creations Phoenix 10 Speedo (as mentioned previously) as it will happily handle the current draw from the motor and through a series of flashing led set-up procedures, the cell cut-off voltage can be set to avoid over-discharging the cells.

25^th December 2004

Thank you darling for my Christmas Pressies.     Job done!!!

All I needed now was the micro servos to go into it. After reading various articles on the web, I decided to go with the Hitec HS55 micro servos at around £11-£13 each.

These weighed in at around 7.6g each and although, there are much lighter ones available on the market (4.4g!!), I felt that I didn’t need to worry too much about the weight difference as some similar models previously built using this set-up were coming out at less than 200g.

Again, I scanned the mags in search of that forever-elusive bargain, only to find that Als Hobbies are doing 4 for £45. Result!! As I only needed 3, I thought a spare servo wouldn’t go a miss, and so with another credit card warming later, Hitec HS55

servos qty 4 were winging their way to me via Royal Snail.

Construction time.

I’m not going to go down the normal ‘kit review building debrief’ as you would

normally read in the glossies, as the construction is as per the booklet provided in the shiny box. ………..Oh no, their not!!!!

To say they were a little vague in places would be like saying that I’m fond of the odd pint of beer!!! I honestly feel that the writer of the instructions is a great believer in the old phrase “A picture paints a thousand words”. If only he would have painted a few words as well!!

It says that it can be ready to flying in just a few hours but allowing time for the UHU Por glue provided to properly set, it took me a few days to get it all together. A long (very long) weekend should be enough.

The speed controller is huge! See pic. That’s a pound coin.

Setting it up requires a bit of patience not often found in today’s modeller and

definitely a need to RTFI (read the flippin’ instructions) prior to starting the set-up procedure. Once read it is really quite a straight forward process.

The motor too, is absolutely huge and the same coin was used for scale purposes. See pic.                                                                          

The 2 cell LiPo 360 mah pack that I went for, simply required the + and - wires (not supplied) to be soldered on and insulated.

The only modification I made to the design was to discard the supplied motor mount and glue the motor onto a 2-inch long carbon tube that I also ordered from www.robotbirds.com.

Nuf’ said.

Now for the fun part!!!

Before the first flight could be carried out, a final check over was done and the CG was set to the recommended position of 60mm behind the leading edge. The instruction booklet states 40-60mm but I wanted to set it up for out and out 3d flying.

Having only flown a ‘shocky’ style plane on my Reflex model sim on the PC, I was eager to see what the general aerobatics and prop hanging abilities were going to be like. I was fortunate enough to have access to an indoor equestrian centre for the flight tests and this is how it went.

First flight half throttle prop hanging with virtually no trim adjustment needed.

Second flight more prop hanging, this time for the camera followed by the usual rolls, loops, control line circuits, inverted flight and torque rolls.  SOOOOOO much fun!!!

I couldn’t stop smiling afterwards!!! Since starting this article, I have been teaching a colleague of mine to fly, using Reflex and so, decided that the ultimate flight test would be for him to fly it as well!!!

No problems at all. For someone who has never taken control of a model before, he was prop hangin’ like a pro after only a couple of warm up flights.

All in the teaching I reckon!!

How Much???

Well, it’s not the cheapest way of going about indoor r/c, but worth it for the smile on your face when you actually fly it. I started flying it at 7.30pm and finally gave up for the night at 10pm. The only reason I stopped was because the temperature in the equestrian centre was around the 3ºC mark!!! BRRRRRR!!!!

Summary

The power from the cd-rom motor is for this application, but for longer flight

durations you will probably be wise to trade up to a 640mah battery, which gives approx 15 minutes flight time. Overall, it is well worth every penny spent.

Useful sources of information on the internet.

www.robotbirds.com

www.brushless-motors.co.uk

www.alshobbies.co.uk

www.overlander.co.uk