Steve Dorling gets to grips with the Century Hummingbird and tests out some new Micro Helicopter Accessories from Like 90

I discovered the extensive range of Like 90 micro heli products whilst searching for a few upgrades to enhance the performance of my little Hummingbird and it was immediately obvious that here was an organisation that was “on the case” so to speak! Century’s cute little Hummingbird , is like all micro heli’s a clever, if simple fixed pitch helicopter for indoor flying and once you master control of these, moving up to a “proper” helicopter is a cinch pro rata! My Hummingbird quickly taught me to fly whirlie’s at very little cost and is surely the best method of picking up helicopter skills and I would strongly advocate this route to learning.

Having witnessed the cost and misery of leaping straight into a grands worth of ic helicopter training where every other landing mistake is a boom and blades job, allied to the availability of all weather indoor practice with no fuel costs makes this method relatively painless. You will probably need a pair of blades and a tail rotor or two – say twenty five quid all in, before you have the job cracked but even that makes this a pretty economical alternative! A boom strike on your Scedau 50 will launch its exploding blades into the ether in shower of wreckage whilst wrapping the flybar around what’s left. Half of the associated bits and bobs will be consigned to the bin and this painful learning exercise will set you back more than a penny or two. Progress with my Hummingbird was rapid and I was hovering within a few hours and within the week, I could fly out the battery with no problem. Not too long after that I had managed my first proper circuit of the lounge. Nose in hovering was the next “stunt” to be mastered and after a few impromptu hacks at the curtains and cupboards (another tail rotor….) we were away! A swift ten minute flight between chores quickly became the norm and progressing to pirouettes and tail or nose in circuits around the house my heli skills increased almost daily. Flat batteries and dents in the furniture became the norm and so, when I became moderately adept I moved into the garden to challenge the wind, thinking that it would be easier with all of that room to manoeuvre My ic heli flying chums had told me that if I could fly the “Hummer” then a “real heli” would be child’s play but I wanted to fly the Hummingbird in the garden first and that’s where it’s shortfalls became very apparent. The two or three weeks of intensive indoor learning that my little Hummer provided was very worthwhile and I quickly wore two of them out but at the price of a decent set of blades for a “real” helicopter, this simple little fixed pitch helicopter allowed me to move straight on to a Raptor 30, sans training gear and fly it.

Well it’s pretty enjoyable but has its limitations, with short duration and poor tail rotor authority that worsens as the battery fades heading up the list. Outdoor or large hall performance is in fact far more of a challenge that hacking it around indoors where it can’t run away or pick up too much speed. When flown in a large space the flight ultimately ends in a crash because the flexible plastic rotors suffer from severe “coning” which causes the helicopter to pitch up until it cannot be controlled effectively and it’s something that always occurs when fast forward flight is attempted. I was very puzzled to see my mate Trevor’s machine go haywire when he first attempted outdoor flight but as he explained at the time, suddenly he had almost no control over it, explaining that the pitching tendency made it virtually unflyable if the breeze caught it or he allowed it get moving. Tough as these little birds are, they won’t take continuous crashes from rooftop height without protest and I wanted better performance from mine so that I could fly it with impunity outdoors. Clearly I was to be thwarted with the machine in standard form and decided that it was time to hang it up and buy a better heli – or was it? The problems then, in short order, of fixed pitch micro helicopters generally are, rotor coning, poor tail authority, short flight duration, and last but certainly not least, motor life, both main and tail which is very short. Starting with those pesky motors, the original equipment is poor and the best that can be said for the stock Hummingbird motor is that it works, but only for around twenty five to fifty flights (if you’re lucky…)! The reason for this sorry state of affairs is a cheap and cheerful six-volt motor running on nearly double that voltage, which is where these delightful little machines get their remarkable performance from. Motors have to be regarded as disposable and although tail motors last about two main motor lives, they are also working very hard and like the main driver, they soon begin to fade. Once your micro heli ceases to answer the controls quite as swiftly as it once did, it’s a sure sign that the motor(s) are on the way out and it’s time for replacements.

Sure – you can do that, but you will need a set of Li-Poly batteries together with a dedicated charger and a full set of dedicated ESC “separates” to replace all your electronics, say seventy quid or so for the brushless motor and its ESC and the same again for the charger and other bits and bobs. Suddenly your Hummingbird isn’t quite the cheap fun that it at first appeared to be. Fortunately now, there is a cheaper alternative, in the amazing little Johnson 250, which is replacement motor option from Like 90. Reports from independent sources on the other side of the pond are favourable in the extreme, stating that these motors seem to last forever and provide added urge too, despite their diminutive proportions. I should explain at this juncture that you cannot simply put the most powerful motor that will fit into micro heli’s because the current draw will be more than the mixer board or batteries can handle. Added to that, too much torque or current draw on the main rotor will reduce tail response and with only so many wiggly amps to go round, it’s a challenging balancing act. The little Johnson really hauls and it has earned itself a very good reputation in the USA. Now it looks set to make waves here too, given that RC Superstore are selling Like 90 products. A tremendous amount of research went into motor selection and not only does the Johnson 250 perform, it’s cheap with it! Great – we have sorted the main motor malady then, so what about that pesky tail end that keeps failing and letting the show down? How about putting TWO motors on the tail drive – these being very light and the extra weight is therefore pretty inconsequential, but what about the current draw? Well if you use two motors then the current draw is actually little different to that of a single set up because they are working half as hard, the net result giving much more tail authority and great longevity – marvelous stuff and exactly what we were after. The machined aluminium Like 90 mount is also very trick and incredibly neat, which helicopter fliers love to see in any upgrade.

Like 90 blades are excellent and whilst you may well have seen some very trick carbon blades around, these are incredibly expensive, costing in some instances, as much or more than a complete Hummingbird. The Like 90 woods are light and stiff and of super quality with a proper airfoil section and when fitted to the Hummingbird in conjunction with the Like 90 head stiffener, that pesky coning and flexing that the original plastic blades suffer from is completely eradicated. The net result is a complete transformation in behaviour, turning the recalcitrant Hummer into an agile performer that can be whizzed around the garden in fine style, with none of the previously impossible antics that it frustrated you with. In original form full down had absolutely no effect on the violent pitch up and the only way of saving a severe crash was to execute a sort of stall turn and attempt to soften the impact at the last moment with a burst of power. As you might imagine, this didn’t always have the desired effect and the Hummingbird would launch itself into uncontrolled lurching that simply increased the problem if you got it even slightly wrong. As soon as those flexible coned blades lift the nose, all control inputs became uselessly ineffective in standard form. So what’s the cost of the complete deal then? Well if you buy absolutely everything – from the blades and motors to the head stiffener and collar – this simple item by the way reduces friction in the head drive train and enhances flight times even further, you will have spent little more than that of replacing stock parts. Believe me, you will be replacing bits as you learn so why not replace the stock parts with Like 90 upgrades, which will prove so beneficial as your flying skills improve. The Like 90 upgrades not only last longer, but they perform at a totally different level, transforming the performance of the Hummingbird and allowing it, for the first time to be actively flown rather than merely hovered around gently. The Like 90 components have totally transformed my Hummingbird, turning it into a different class of machine. Please do not for one moment think that I am criticising the stock Hummingbird (or it’s many counterparts) because at the price, these micro heli’s fly well, but they are essentially toys and once you are past the hovering stage, you will want to move on to forward flight and the Like 90 parts now allow you to do that. These products which have given my Hummingbird(s) a whole new lease of life and I have fallen in love with it all over again. The shot on the right is the Hummingbird being flown outside with full authority ~ just try that with the stock bits and bobs installed. There are a few tips that are worth passing on to those contemplating these modifications, no matter whether you have a Jabo, Piccolo, Hummingbird or any other micro. All of the low end micro machines are of similar performance and Like 90 produce excellent upgrades for them all, from fully symmetrical blades for collective 3D to the odd bracket in alloy to give your heli a little “bling bling” – beloved of all. Every component has been engineered and developed to perform and look great.

I did a few other mods and upgrades to my Hummingbird whilst fitting the Like 90 parts, the first of which was to lose that expensive and unreliable “Hummingboard” which had just failed spectacularly with a flash and an acrid electronic smell that denotes any “jiggered” bit of radio gear! Replacing this single component with separate ESC’s (I used GWS 50 and 100) is possible if you own a transmitter with revolution mixing (I used a Hitec Eclipse 7) and the end result is very worthwhile. Those all in one boards have no protection circuitry and because of that you are on borrowed time from day one. Some of the later helis have everything lumped together, ie the receiver, gyro, mixer and two ESC’s all on one single and very pricey board, which essentially means that a crash with the throttle on, which is likely to burn the board out, will set you back a fortune. With separate ESC’s you can replace “half” of the speed controller if need be which is very cheap pro-rata rather than fork out for the whole on board package and best of all, you have all the mixing facilities in your computer TX for fine tuning. There is an excellent article on how to do the conversion here http://www.helihobby.com/html/tipstricks.html If you go for the extra tail motor then you will need to move the battery forward to achieve the correct C/G and for that you may need to trim the underside of the canopy for clearance. C/G on a helicopter by the way is exactly on the rotor head, which is obvious once you think about it I guess! Other than that, there seems very little work involved in the conversion(s) described, providing you can wield a soldering iron and a few hand tools. Go for it, you will be so pleased with the results! Increase your end points to max on the main controls for maximum authority and don’t be afraid to experiment with exponential to fine tune, both of which are worthwhile exercises.

For a full range of Like 90 upgrades for micro helicopters across the board, RCSuperstore, who are the sole importers and agents of these superb products. They carry the full range to suit all of the popular micro helicopters. Do it now, you won’t be disappointed!

Article by Steve Dorling for Bumpy Green Model Aerodrome
October 2004

Comment by Steve Dorling on 20041009123912. Rating 5

This evening, the wind abated for the first time in a month - took the Hummer out and pushed it to the limits - up to a dot in the sky, nose down flat out, up into a stall turn - just brilliant - like a mini Raptor in fact!.

Comment by Duncan Cartwright on 20041009132738. Rating 5

I need a replacement pivot head and main rotors for my Hornet indoor heli, like you i've been destroying my parents furniture a little too vigorously!!! Any ideas where to get spares from?

Comment by Si on 20041031193955. Rating 5

Now I know where I've been going wrong! - I can hover my Jabo around my garden with no probs, but I lose control when I try circuits in larger areas. I will try your mods - thanks for your help

Comment by PC on 20050707164322. Rating 5

If you’re looking for something between the low rpm plastic blades and the wood blades, try trimming a little off the trailing edge of the plastic blades, like 6mm to 3mm (root to tip), it instantly increases the rpm and reduces the coning angle. You may have to adjust your gear ratio to get the rpm up.

Comment by Ryan on 20051116005432. Rating 4

Do you think these upgrades will be the same for a Jabo? From what I have read the Hummingbird came before the Jabo II.

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