air space

Street Photography with a difference!

JOHAN BJURLING comes from Stockholm, Sweden, and is a member of the Stockholms Modelflygklub of Stockholm - the home club of our other contributor from Sweden, Tore Loodin.

For his venture into aerial photography, Johan built this Taylor Cub from Balsa Products which he converted to electric flight. He fitted it with a Speed 400 motor, geared 2:1, and a "Powercircle" speed controller mounted directly behind it. A 7-cell 500 mAh Sanyo pack provided sufficient power to fly for 8 - 10 minutes. The radio gear was a Simprop Pico, controlling 2 HiTec HS-80 servos. The finished model had a ready-to-fly weight of 17·5 ozs (500 gr), a wing area of 300 sq. ins. and a wingspan of 49" (1250 mm). This is the only picture that exists of the model which, sadly, "is no more". The speed controller apparently proved a little too weak and the motor suddenly stopped. Johan was in a very awkward place, so the plane ended up in a large tree and he never did find the wing!

Johan continues with the story:

I have taken some aerial photos from this little plane. I used a Kodak disposable camera and a FMA S-80 servo to operate the trigger. The plane handled the weight of the camera and servo (85 gr.) with no trouble at all. Even ROG was possible. The servo was mounted directly to the camera using double-sided tape. The paper on the camera was removed first. The camera was mounted to the plane with rubber bands.

I did the first flights at my "normal" R/C-field. But I did not only want to take photos of grass, so it was time for the big challenge - to take a photo of my own house! There is a small field within a 2-minutes walk from home. I planned to take off there, and walk with the plane towards home. I did, and on the way I met some young mothers, taking a walk with their children. You should have seen the look on their faces when they realized why I was looking skywards...

Well, after taking the first picture I was too lazy to walk back to the field. I decided to land on the street instead. Oh yes, it worked out fine. The wind was straight down the road... Wind up the camera and off for a new mission. Hand launch, and away. Took one more shot, and headed for the field. Did not want to run out of power . . .

This is the lucky shot where I caught my house on film. This one was taken from the field. The shots when I did the adventurous walk were not quite so good - I just got my neighbour's patio through flying too low.

The picture to the right shows the field where I started from. I took it a couple of days earlier when it was snow on the ground. It is rather late, and the sun is about to set. The pictures get much better when it's bright sunlight, but they're fair, minding the equipment used, I think.

I told Johan that I was amazed at his stories of flying his models in his garden and along the streets - it's something that would cause concern in the UK and probably lead to trouble if we tried it - and I had certainly not heard of anyone giving it a try! Johan commented:

With a real Slowflyer it is actually no problem at all. The weight is only a fraction of the weight of a "normal" model, and the speed is really low. They normally weigh between 100 - 300 grams (3½ - 10 ozs) and they fly at about walking to jogging speed. They can hardly cause any damage; not more than a R/C car, anyway! And there is almost no noise at all. I have been flying models under the street lamps after midnight. Just have to mind the TV antennas . . .

. . . and here is Johan coming in to land in his garden!

johanbju@hem.passagen.se

Johan's own website is featured on the site seeing page.

To save getting myself into trouble, I think I should say that I am not as sure as Johan that flying even slow-flyers in a built-up area is a safe practice, and feel that even a light-weight model could cause some damage if out of control. In the UK, the British Model Flying Association's Safety Code instructs its members "DO NOT OVERFLY houses, domestic gardens, car parks, traffic", etc. I include this comment simply to ensure that no one suggests that the inclusion of this item implies that we should all go out and have a go! - Reg.

Mode 1

some comments by Gordon Cook

There are are two main transmitter control set-ups, or 'modes', in use today throughout the model flying world, conveniently referred to as 'Mode 1' and 'Mode 2'. In both modes, sideways movement of the sticks produces precisely the same effect, with the left-hand stick controlling the rudder, or tail rotor if we are talking helicopters, and the right-hand stick controlling the ailerons or lateral cyclic, causing the model to bank left or right. However, throttle and elevator controls are allocated to opposite sticks between the two modes. Mode 1 transmitters use the left-hand stick to control the elevator (fore and aft cyclic) and the right-hand stick controls the throttle (pitch), whilst on Mode 2 transmitters the elevator is on the right-hand stick and the throttle on the left. According to Dave Day in his book Flying Model Helicopters, the two types of transmitter are roughly evenly split throughout the world amongst fixed-wing flyers, whilst Mode 2 is predominant amongst model helicopter pilots. There is also the 'cuddle box', sometimes called Mode 3, which has a single stick, including a twisting action, for the three principle movements, and a lever on the side of the transmitter for throttle control. In this case, the transmitter is held in the curve of the left arm (hence the 'cuddle box' tag) and the throttle lever is operated by the left thumb. Here, Gordon Cook, Chairman and Principle Training Officer of Test Valley Model Flying Club, UK, comments on his perceived advantages of Mode 1 insofar as fixed-wing flying is concerned.

Without wishing to re-open the debate on the Mode 1 versus Mode 2 argument, here are several practical observations that I have noted during my time training people. I wonder if anybody else has similar experiences which could confirm or refute these opinions.

First of all there is the classic situation that so often results in a broken aeroplane - and I hope that doesn't sound too familiar! Imagine the aeroplane is heading toward the pilot on the landing approach. Almost at the point of landing, as the flair-out is in progress, a corrective roll command is entered, but unfortunately in the wrong direction. It seems to me that this problem occurs more with mode 2 fliers than those using mode 1.

When I started more than a few years back, most UK transmitters were on mode 1, following the way the old reed sets were configured. Left hand pulls the switch back for up, right hand moves the switch to the right to turn right, etc. Then our American friends introduced us to the cuddle box single-stick, 3-axis, transmitter and later the Japanese manufacturers swamped the markets with the later US style mode 2 transmitters. So the upshot is maybe mode 2 is natural for some, not for others.

Another observation concerns the ability to trim an aeroplane, and here again, I believe mode 1 has the advantage. It seems this is quite a struggle for novices. The thumb movement to me appears more natural on mode 1 where each thumb takes control of a separate trim lever and the awkward crossover caused by the right thumb reaching the elevator trim in mode 2 is avoided. I think this can lead to a reluctance to trim in mode 2 and poor flight accuracy results.

My third example relates to the ability to fly the basic loop and roll accurately. I have noticed that mode 2 fliers often mix in some inadvertent roll command when they pull a straight loop or find it difficult to fly an axial roll rather than a barrel roll. To some extent, this is a weakness of the stick design which is a compromise between stick spring tension in either direction and in the diagonal sense; or perhaps it is just the left-hand side of the brain being overloaded again. If, for example, you set the elevator spring rate to be weak compared to the aileron, the tension may well appear to centre the stick to move fore and aft, with resistance to sideways deviation - and hence a truer loop. Conversely, the ability to move diagonally is impaired. So the feel of feeding in a correction on the alternative axis tends to seem more awkward. Using mode 1 set-up, both these points are avoided since the elevator and ailerons are controlled on split sticks, and the spring tension in the primary controls can be adjusted to optimise the preferred feel.

However, as with all things, I expect that practice makes perfect and problems with either set-up can be overcome.

It would be interesting to do a survey of world champions to see which mode they use. Probably mode 2, since they are all 'youngsters' under the Japanese influence. Better still, and more appropriate to general sport flying, it would be interesting to establish which mode allows learning to a competent level quicker. Even then, maybe slower is better!

I would be interested to hear any comments.

I do not really understand Gordon's first point concerning the corrective roll on landing, since the same stick is used in both modes for aileron control (or am I getting it wrong?). I certainly see what he's saying about trim controls and can also see some merit in having the elevator and aileron controls on separate sticks.

But what do YOU think? Have those of you with training experience in both modes got any views on this? It would also be interesting to see whether the two modes are evenly split across the world, so why don't we carry out our own mini-survey? Send me an e-mail simply stating what mode you use, plus any other comments you may have on the merits/demerits of either mode as you see it.

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