Flying from water?

Treat water like concrete and you'll not go far wrong.

Although I’ve been model flying now for over twenty years, it’s only recently that I’ve realised my long-term ambition of flying off water. It’s a desire I’ve harboured ever since building my first trainer and one that probably stems from my earlier interest in model boats. Yes, it’s true, many years ago I was a hardened model boat enthusiast with an enviable collection of yachts, cruisers and powerboats. I still believe model boating to be one of the most relaxing pastimes in the R/C model world, a fact that owes much to the simple pleasure of being close to water. It’s hard to beat when you need to unwind, indeed if you’ve a particular fascination with ships and a bent for modelling, it really can be an intoxicating and very addictive pursuit.

So what of my float-flying exploits? Well, having learned to fly, combining my two R/C interests seemed an obvious and very desirable step, although, as I’m sure many will have found, ponds lakes and reservoirs are hugely popular places for all manner of recreational activities, and none mix terribly well with model flying! I think it’s fair to say that suitable floatplane locations aren’t easy to come by, although as recent experience has taught me, they are out there and if you’re determined to find one (and happy to put yourself out) you’re almost certain to succeed.

Advert

Enjoy more RCM&E Magazine reading every month.
Click here to subscribe & save.

Take our first venue for example: one of the most popular wildlife and watersport centres in the Southeast and the very last place you’d expect to get permission to fly a model aeroplane. Yet, determined to find somewhere to christen the Nijhuis Spruce Goose and my ARC Cessna, Tony and I not only got permission to operate from the sailing club slipway, we got to park our cars right by the water and were offered a small rowing boat for model retrieval. As a direct result of remaining respectful to those who had paid to fish or sail the reservoir, we were able to turn the one-off session into an open invitation that allowed us to return on practically any summer evening we fancied. We never considered the venue a permanent solution, our flying all too often interrupted by the comings and goings of sailing boats, however we flew the reservoir three or four times whilst on the lookout for an alternative.

Clubmate Eric's Inwood Improver with a VMAR float kit.

I guess one of us must be righteous for we very soon struck gold in the form of a small three acre irrigation lake that fruit farmer and flying pal Andy Boxall was about to start digging. A year down the road and firmly established, the reservoir is perfect for .40 – .60 size models with the added benefit that one’s aeroplane is never far from a bank and will invariably get blown to shore within minutes of a dead-stick or a dunking! Mind you, don’t be under the impression that ending every flight in an unscheduled splash is de rigueur – it isn’t! Most of the guys in our small but expanding group of enthusiasts have enjoyed nothing but success in this respect, indeed the only bits of my Cessna that have made contact with the water so far, are the floats!

Advert

GETTING STARTED

One of the great things about flying from water is that you needn’t spend a fortune on your model. Seven of us currently gather at our impromptu splash-ins, and of these most have either converted existing designs with proprietary float sets, or bought second-hand aircraft, ready to go. One, Don Denne, even took the bold step of designing his own floats and attaching them to a Ripmax ARTF Tiger Moth, with tremendous success I hasten to add! Others have bought established model and float combinations and, not to be outdone, Nijhuis is just about to test fly a 72” span Sunderland, which is almost guaranteed to be a beauty. Don’t you hate clever people?

Of the other models we’ve seen, Mr Ashby Snr (dad, to me!) built a float-equipped Electric Kitten from the Flying Models (USA) plan, farmer Boxall has been campaigning a Multiplex Mini Mag, and there’s even talk of a float-toting Mighty Mouse making a show. Me? Well, as I’ve mentioned, I chose the ARTF route and simply converted my ARC Cessna 177 with the company’s custom float kit. Designed to fit like a glove, ARC’s plastic floats are beautifully engineered, enhance the appearance of the 177 immensely, and guarantee success… That’s my kind of water flying!

Advert

GOING RETRO

It’s surprising how many retro’ float sets are available when you start looking. In fact, if anything, the numbers are increasing. One of the lists below has the sets I’m aware of, although there are doubtless more. Whilst I know for a fact that Graupner do one, I haven’t been able to establish if it’s readily available in the UK.

Clubmate Eric Pearce bought the VMAR versions, fitted them to an ancient Inwood Improver and is having great success. Truth to tell, the new floats have given the tired old hack (the model, not Eric!) a new lease of life. From Eric’s experiences, and others in our group, it seems unnecessary to get too bogged down in the science of fitting floats. Follow the manufacturers recommendations wherever possible, noting the general rule of thumb advising that the step be positioned just behind (10 – 25mm) the centre of gravity, with the wing at between 0° and 3° positive incidence to the top surface of the floats. Keeping within these guidelines seems to maintain the effectiveness of the floats on the water whilst having no adverse effect on the flying characteristics of the model once airborne.

Advert

My hack – the ARC Cessna 177, the float kit is sold separately.

OPERATIONAL CONSIDERATIONS

It’s fairly obvious when you think about it but once your i.c. model is taxiing on the water you won’t be able to stop it moving unless you kill the engine, which, of course, you’ll not be wanting to do. Since the aeroplane is always on the move, then, a water rudder is a bonus in that it aids taxiing and allows you more than one attempt at positioning the aircraft for take-off. Without the rudder, and in anything but calm conditions, waterplanes are very unwilling to taxi crosswind, the fin acting to weathercock the model back into line. A burst of power will sometimes have the desired effect in ‘driving’ the aeroplane through a turn, although if the wind is strong enough this manoeuvre can be hazardous, the breeze getting under the wing and tipping the thing on its nose, much like it does with certain tricycle undercarriage designs. Lightly loaded high-wing types seem more susceptible to this, but none are exempt.

In terms of wind strength, I’ve learned that I can comfortably fly in gusts of up to 15mph but thereafter it all gets a little choppy for my Cessna. The breaking waves on the tip of the floats throw water at the propeller, which magically turns it into a fine and very far-reaching spray. On tick-over, if too much wet stuff is lobbed at the prop, the force can be enough to stop the engine and, of course, leave you like a sitting duck. Obviously, the higher the prop from the water the less of an issue this becomes but either way, different models will have their limitations which, for the sake of avoiding an early bath, it pays to establish.

As for flying? Well, take-off is generally straightforward, although it’s surprising how much extra power a floatplane needs to make it unstick on a calm day. My technique seems to work well: hold in full up elevator as you taxi into position, line her up dead into wind, then open the throttle positively and progressively to get her on the step as quickly and smoothly as possible. I seem able to ease the elevator forward at this point, but not much; at Andy’s reservoir, and with the Cessna racing towards the far bank, the point of no return comes all too quickly. With this, ‘full up’ lifts her off the water with relative ease and she climbs away with appreciably more effort due to the additional weight and drag of the floats.

Don's Tiger Moth tripped when taxiing, no water was taken on board though.

Now then, landing! As I’m sure you appreciate, water can be darn hard stuff when you want to put down on it, especially since the shock-absorbing qualities of floats are practically non-existent. Mind you, the experience does wonders for your landing practice and unless you’re happy to skip across the pond like a bouncing bomb you’ll need to grease the model in, keeping the nose high and making sure the back end of the floats touch the water first. Once the wet stuff has grabbed the stern (nautical term for the blunt end), the remainder of the float will be drawn in very quickly and you’ll find the overall stopping distance of a floatplane very short indeed. Satisfying? You bet, and with the aid of a water rudder you’ll find yourself taxiing back and doing it all over again just for the hell of it and the sheer pleasure of watching the model produce that terrific bow wave and gorgeous wake. Landing and taking off from water really is an incredibly rewarding experience and if you’re anything like me, the bit in-between will become secondary. After all, you can fly aerobatics anytime, but how often do you get the chance to see your aeroplane skipping low over water? Kissing the surface with the floats, then gently powering up and going around is not only exciting to perform, it’s delightfully pretty to watch and very satisfying. On calm days low flying seems even more exciting than over land, figure eights being a real treat to fly with alternate wing tips teasing the surface.

This RCM&E plan Laker handles beautifully.

TO THE RESCUE

We’ve had terrific fun with our ramshackle collection of floatplanes and flying boats. Nobody’s broken a model yet, nothing has sunk and no-one’s fallen in. We’re all totally hooked and can’t understand why we didn’t do it years ago. Incidentally, before I go, it’s worth mentioning that on the odd occasions when disaster has struck in flat-calm conditions, we always make sure we’ve a model boat on standby to nudge the casualty back to shore. A short time ago I bought my girls (lucky girls eh?) a ready-to-run Thunder Tiger trawler. Catherine (our lobster boat) hasn’t made it to the local park just yet, though she has put in some sterling service as a seaplane rescue launch!

Catherine the Great – an R/C boat may come in handy now and again!