Month: February 2017

Downtime

The weather has been appalling recently, with gale force wind and rain, so I’m stuck inside this weekend. I’ve been keeping busy by converting another of the HubSan X4Cs for a workshop we’re running in March. It took all day as I’ve been filming the process as I go along, so it should be interesting to see how the final video turns out. This time around we’ve also got a £20 FPV camera so we can give them a go with the FPV goggles.

DanaTheDimorphodon.png

Also for the workshop, I’ve been playing around with a new design of 3D printed frame. This time, it’s a Dimorphodon dinosaur skeleton. It’s a bit ambitious, and I’m not sure if it’s going to work, but it’s been fun sketching it out. I think I’m going to stick with the flat style of 5mm high extruded frame rather than go the whole hog and make it properly 3D. I’m not entirely sure where I’m going to put the four motors yet, though.

In addition to this, I’ve finally got two new LiPos for my RS352.

I opted for some Hyperion 1300mAh LiPos, similar to the original ones which worked really well. I ordered them from Robot Birds on Sunday and they had arrived by Tuesday. Fantastic, but those XT60 connectors will have to go as I use the Deans ones. I would have swapped them over today, but I’ve been filming the HubSan conversion process for most of the day. That can wait until next Saturday when, hopefully, we’ll have better weather. It sounds like the wind is trying to tear the roof off at the moment.

 

Advertisements

Where Did the Sunshine Go?

I got up this morning and it was bright and sunny. When I got to the flying field, though, it was overcast, windy and cold. I don’t know what happened, but everybody else who arrived had the same experience. The weather just sort of changed between the car park and the field.

It was a very busy morning with the helicopter guy there practising when I arrived. He looked like he was trimming a new setup as he was very deliberately going part way through a manoeuvre, then stopping and trying the other way around.

Then I had a visit from a swan who flew around the field and then flew back in the direction he came from. After that there was a father and two sons who had a foam Piper Cub aircraft. I’m not sure who made it as there weren’t any markings, but it went surprisingly well in the, now extremely gusty, conditions. Both the dad and the older boy had a go at flying, with the boy really throwing it around the sky. He managed to hit the dustbin with the prop at one point, but it kept flying, only to be stopped on a later flight when he did a half loop to inverted and then pulled back instead of pushing down and slammed it straight into the ground inverted. I’m impressed that a small foam Cub could fly in that wind, especially rolling and flying inverted on just rudder and elevator. They’re now looking for a first aileron model to improve their skills on.

After that, the EFlite Advance arrived and the guy whose Hurricane I flew a few months ago with an electric balsa glider called a “Faze”. This was covered in black and red film and flew very well. He’s now looking at a Fokker DR1, so that should be interesting. Also, I think it was the guy who had a DJI Mavic in a backpack a few weeks ago with his son (plus Syma drone) and a friend who he was teaching to fly with a buddy box. They had the Hobby King Bixler (Easy Star clone) and a very boxy looking aircraft which he had started building in the year 2000. Apparently, the SIG elastic bands which held the wing on were authentic 17 year old ones, but had been stored in a box and were fine to use. This wasn’t its first flight, but the first one of the day was just as I had to leave, although it seemed to be buzzing around the field at a rate of knots. Also flying at some speed was the Stryker, back after not being around for a few weeks.

My flying this week was slightly curtailed by my LiPo situation. The first flight didn’t feel like all the power was there. This was with the newer (1 year old) 1100mAh Hyperion EX G3 cells. These are 3S 45C cells, so I should be nowhere near their limits with my RS352, and yet both packs have puffed up and seem to be on their way out. In contrast, the older (4 years or more) CX G3 1300mAh cells have puffed less and lasted better. Both now have two cells where the voltage isn’t holding up, but still fly better than the newer ones. So, the first flight was not much over 3 minutes, then the second one on the other pack of new cells had a lot more power and lasted 6 minutes. The flight with the first older pack, after charging to bring the two duff cells up to voltage, had the most power and was around 6 minutes again. I never got a fourth flight as I ran out of time before the two duff cells on the final pack got over 4.0 volts (I got them up to about 4.15 on the other pack before aborting the charge and trying them out in the air).

As for the flying with the RS352, I’m still trimming it with the new servos, so just a few cuban 8s, loops, rolls, flick rolls, stall turns and spins. The conditions weren’t really up to much more than just trying to stay in the sky. The conclusion is that I need new cells, so I’m off to do some shopping.

Winter Weather

It’s cold. It’s windy. It’s dark. We had sleet and snow yesterday and today’s not much different. I might have got some flying in this morning, but I decided to stay indoors in the warm instead. It hasn’t exactly rained, but there’s been this sort of mist that’s in the air.

I’ve been making butterflies instead this morning.

It’s a 3D printed frame for a micro quadcopter that we use for the Drones Masterclass that we run at work. The next one is at the end of March, but the 3D printing and all the manual work required to make them fly takes up a lot of my spare time. This one’s ready to go, so I’m going to spend the rest of this afternoon trying to get my head around the 3D CAD software to make another design. Each time we run the workshops we try and make small changes so that we’re constantly improving the format.

Just as I’m about to finish, it now really looks like it’s going to snow. It’s been threatening like this all morning, but now it’s getting very dark. Definitely a building day, although I might put my other micro quadcopter together and race it around the house later.

I Can’t Feel My Fingers

It was damp and windy and absolutely freezing this morning, but I just about managed to get some flying in. When I arrived, there was a guy practising with his DJI Inspire and the Sun was out, making it feel fairly pleasant. Round about 11am, though, the clouds all rolled in, the Sun disappeared and the wind picked up. My first flight with my RS352 wasn’t too bad, but for the second flight, the conditions were a lot more turbulent. At least I seem to have fixed the problem with the prop coming off. I managed one more flight this morning and that was all I really wanted. My hands were freezing and I was shivering to the point of the aeroplane shivering in sympathy. I didn’t think it was going to be that cold, but it must have been the wind. Either that or I’m just getting soft.

Anyway, after the Inspire guy went I was joined by a DJI Mavic, then another Mavic which flew across the field ahead of its owner as he walked across. The Multiplex Xeno also turned up this week, having said that he tried to fly last week, but the rain had set in between the car park and the field. My decision to sit it out at home and wait for the rain to come looks like the better option. The Xeno had a couple of flights, but also succumbed to the cold finger trouble. I really do love watching flying wings as they look so graceful and slippery in the air.

That’s about it, but I took some film of the Mavic when it was landing as I was interested in the geometry. I hadn’t had a good look at one before, but the front blades are mounted above the rear ones, with very little separation between them when they’re spinning. When I first noticed the vertical separation, I did wonder whether the blades actually crossed over the same way they do on a Chinook, but there is a small gap. It might be more a function of how the aircraft packs down into a small space rather than having any aerodynamic advantage?

See what you think of its stability in the video. You can hear the wind on the audio which gives an idea of the conditions this morning.

OK, I have some quadcopters to fix this afternoon as we’re running another Drones Masterclass in March and I’ve just discovered that one of the frames is damaged from the last one we ran in November.