Author: rwmilton

Autogyro Flies!

After starting the build in Autumn 2014, I can finally say that I’ve fulfilled my ambition to fly my own autogyro. It didn’t all go completely to plan, though.

Last night I added a bit of extra shim to the blades to help with the spin up:

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LiPos charged, I was ready for the first flight of the day, so, here we go again…

 

I decided to use the wind to spin up the rotors and then hand launch, which worked last week when I got my first 10 second flight. This week it was a bit windier at around 8mph, which I figured was perfect. This time I had the trims zeroed, so the head head was at 90 degrees to the mast, which is the recommended position. I tipped the aircraft back so that the nose was vertical, the blades spun up to a speed where there was a definite “lifting noise” from them, increased the throttle and rotated to the horizontal launch position and released the aircraft into the air. Immediately it wanted to go backwards and I spent most of the 20 second flight with the elevator stick all the way forwards trying to control it. Anyway, the landing wasn’t too bad, in long grass over to my left and downwind. On recovering and checking the aircraft, I discovered that the right fin had snapped in the landing.

 

I borrowed some cyano and patched it up with sellotape, then I moved the elevator trim all the way forwards and gave it another launch. I had a four minute flight with it this time, flying backwards and forwards in front of myself, demonstrating some semblance of control.  This time I was actually flying it, even if it was a bit of a handful to start off with. The thing is, it was pulling badly to the right, so I spent the first few minutes gently dabbing in a couple of clicks of left aileron trim until it was flying more comfortably. That’s 25 clicks of left and about the same on the down elevator prior to flight, which explains my earlier comment of, “a bit of a handful”. Especially when you’ve never flown an autogyro before, and it is a very odd thing to fly. Also going through my mind was the fact that the fin was held on with sellotape. That’s why I was very reluctant to use the rudder, but I did  give it a go near the end of the flight.

As for the flying, the elevator controls the speed, while the throttle controls the height. I did actually get up quite high at one point, but I was very careful not to let it get too far away from me as the orientation is a problem. I had a couple of moments when it was turning towards me and I lost orientation. What really surprised me was how much height I was losing on the turns. I was flying off to my left, turning 180 degrees, losing half my height, then picking the height back up again as I flew in front of myself, only to lose it again on the turn at the right hand side of the box I was flying in. It didn’t seem to matter if I turned left or right, the height loss was the same, and there were a few points where I couldn’t turn tight enough to fly in front and had to do a big circular circuit around my head. There didn’t seem to be much authority in the turns, but I can live with slow and docile at this point. Like I said before, I did very gingerly try the rudder out at one point and it was effective in bringing the nose around, but I was too scared of the cyano and tape on the fin giving way to do very much. Anyway, that was the battery exhausted, so I had to think about landing. This proved to be very easy and I touched down with almost zero speed and so lightly I’m sure my pilot in the red baseball cap never even realised. The only thing to mention here is that it’s very important not to reduce the speed too much. I was on the point of doing this and could feel it rolling left as the speed was decreasing. Post flight analysis of the battery showed that it only had 10% left.

Four minutes of autogyro flight! I’m only saying that again because it goes a bit downhill after that. On the next flight, the launch was fine, but it just didn’t seem to have any power. I can’t understand it because I did two launches, and both times it didn’t want to climb, landing about 20 seconds later. On both occasions, there was ample power when the aircraft was recovered. I decided to charge up one of the new 1300mAh packs and see what difference that made, but I’m fairly sure I made a mistake launching. There wasn’t enough speed in the rotor when I released it, the aircraft went away, but climbed too fast and rolled to the left. It was like it did a stall turn from my hand and I almost managed to recover it, but it hit the grass quite hard on the two wheels and tail skid simultaneously. This had the effect of partially splitting one of the spruce longerons and put paid to any more flying.

 

I always suspected that a hard landing would cause a break like this, but it’s easily fixed with some glue and a couple of plywood doublers. In my defence, I think the rotors were spinning at the right speed, right up until the point where it left my hand. The wind dropped at just the wrong moment, causing the rotor speed to drop as I brought the aircraft up to the horizontal and applied throttle.

Anyway, I’m very happy now that I’ve achieved my lifelong ambition to fly an autogyro, so I’ll fix it up and have another go soon. Oh, and by the way, there should be video of the event, assuming the camera worked. I haven’t had time to look yet. Post-flight analysis of the flights were there was no power could be interesting. I’m wondering whether I was pulling back on the elevator more than I realised, rather than giving it throttle? I really don’t know, as I definitely had 100% throttle and had to back off to land. Would forward tilt have increased the speed and built up lift? What I would really like is some sort of telemetry to record my transmitter inputs along with the flight video.

As for the rest of the day, I had a single flight of my RS352 right after the final flight with the autogyro. I buzzed around the sky with an old Corsair, which was a lot of fun. We were dogfighting with each other, but pretending that we weren’t. Him and his father between them had a fair few aircraft, including a Lazy Bee and a UMX Beast, which I’ve flown before and which he threw around the sky very convincingly. There was another guy who helped me with the autogyro last week, but this time he had brought his son and was teaching him to fly with a buddy box. I haven’t seen that for a long time, but together they were flying a Bixler. I also discovered that the aircraft I maidened last week wasn’t a Bixler, but actually a SkySurfer. The same guy was here again this week, but with his Nieuport biplane this time. Unfortunately, the Nieuport had a bit of an incident on its first take-off, then got into the air, completely out of trim, gradually settled down into flying, but suffered another incident on its second flight. This time it looked like the top wing was damaged, so he went back to his car and brought back a contra-rotating helicopter. This also flew, but it looked like the wind wasn’t its thing. When I had to leave at the end of the session, I left him with my sellotape fixing something on it. We also had a lady with a micro drone, brushless, and made from carbon fibre. I think I last saw her on the autogyro’s first outing a few weeks ago, but a couple of her friends also turned up with drones. There were also another couple of drones at the opposite ends of the field not wanting to talk to us (I wonder what they made of an autogyro flying past?). Finally, the guy with the Bixler also had an own design, small, agile, high wing plane that he spent the best part of a decade building. He asked me to have a fly of it and see what I thought. Well, it’s actually very nice to fly. I thought it was going to be very sensitive to roll, but actually, the controls were very well balanced. It was fast, agile and aerobatic, without being overly so. Anyway, he’s got a SIG Cobra pattern ship type plane that he’s just finished and wants to fly next week.

That’s about all there is for this week, except that I’ve still got the video of the autogyro flight to have a look at and edit, plus some repair work to do. I’m still determined to make the autogyro a regular flier.

The Night Before the Autogyro Test Flight

I’ve spent most of today getting the autogyro ready for its third test flight tomorrow. Firstly, I now understand what the shim under the blades does. As the blades are fixed to a flat disk that spins, if the blades were at zero degrees incidence, then all the lift produced would be upwards. The shim gives the blades negative incidence, so there is a small component of the lift in the forward blade direction. Now, with the blade fixed to a spinning disk, this forward component of the lift makes the blade spin. The more negative incidence you add, the more force there is to spin the blades.  There must be an optimum amount of incidence which causes the blades to spin at the correct speed to produce enough lift for flight, but I haven’t worked it out yet. I’ve just added a bit more to my blades for tomorrow’s test flight. It’s easily removed if it doesn’t work, though.

The next thing I did was to correct the tracking by bending the left u/c leg back into position. I can’t think how it got bent… Now it looks nice and straight, so I’ve moved on to looking at the control movements. There isn’t much I can do here, except make it all nice and square and get the head back to 90 degrees to the mast, which is the suggested neutral trim position.

Then I had a look at the videos of last week again. It’s all very consistent when you watch. As soon as it gets to a certain speed something kicks in and it yaws abruptly to the right. After wracking my brains about P effect and gyroscopics, I realised that I was missing the obvious. It’s almost certainly the reaction force as the the rotor head spins anti-clockwise. The yaw force is clockwise, so that great big triple rotor on the top is the most likely culprit. I took the head apart, I oiled the bearings and I put it back together again, which is about all I can do with it.

That’s all there is to it really, so I’m hoping for some wind tomorrow so I can do a hand launch. We’ll just have to see how it goes.

First Flight: The Autogyro Flies

 

I flew the autogyro! I don’t care about anything else at the moment, I finally flew my own autogyro. As an added bonus, I also managed to catch the flight on my RunCam. I honestly thought I was gyronauting for at least 30 seconds, but the video says it was only 10. It must be down to the number of control inputs I was having to put in, because this was one first flight which didn’t exactly go to plan. To begin at the beginning, I put bigger wheels on the Atom to increase my ground clearance and hopefully help the ground run build up rotor head speed. You can see the big foam tyres in the pictures. I must have spent the best part of an hour running along the ground with it doing exactly the same thing every time. There’s lots of video of that too so I can analyse it later. The aircraft runs straight initially, then veers off to the left as soon as the head gets to a certain speed. I tried altering the head angle (aileron) and rudder to counteract this, but to no avail. If I did get up enough ground speed for the head to spin fast enough to lift, then what would happen is that the right wheel and tail would lift, but the left wheel refused to unstick. I got very proficient at careering along the ground on just the left wheel and dragging the left fin, before crashing into the grass at the left edge of the runway. I just couldn’t get it to track straight and really need a fatter section of flat grass to take off from. The wind wasn’t helping either, because it was very thermic and the wind was from all directions during the morning, but never much more than about 5mph.

To cut a long story short, I hand launched it. One of the guys flying DLG had come over and suggested hand launching, but I was very reluctant, unless I could see the rotor spinning up to speed first. This is where I now owe the weather a favour. While I was discussing the YouTube video I had seen on how to hand launch an autogyro, the wind picked up, the rotor spun up to speed and I just looked at him and said, “that’s it”. With the autogyro’s nose pointing vertical, the rotors were spinning furiously in the wind, I did a control check, rotated it smoothly to horizontal and pushed it forwards. It flew. Well, I say it flew, for the next 10 seconds I had the sticks in all four corners in order to avert was was increasingly looking like a crash. I think my helicopter flying skills kicked in at this point, because that’s what I was doing, watching the rotor head, keeping away from the ground and trying to stay flat and nose down. Needless to say, the head was too far back and it was flying on a stall. Everybody thought it was going to crash, but I’m able to walk away with 10 seconds of autogyro flight, an undamaged aircraft and a lot more knowledge about autogyros. I can’t wait for next time.

Autogyros aside, it was a very eventful morning for other reasons, not least of which because the weather was perfect and there were more people and aircraft than I’ve seen in a long time. There were already three guys flying DLG exceptionally well when I arrived and another with an own design trainer using the path as a runway. Then the guy from last week arrived with his F15, bringing along his daughter this time. I got to launch the F15 on its first flight. Somebody was flying a drone (noisily) over by the river. My first flight of the day actually came from the guy who brought a UMX Spacewalker over on his bike. The Atom was actually my second maiden flight of the day as another guy I see a lot had a brand new Bixler. I flew his Hurricane a few months back, and he was going to fly this himself, but then we got into, “I can stand next to you while you fly if you want… can you launch it for me… why don’t I just give you the transmitter and you fly it?”. So I flew it for him, which was probably a very good thing. I noticed on the ground that there wasn’t much aileron movement and it really did need more in the air. Luckily the rudder worked OK. I had to check the rate of ascent from the launch, as it wanted to go vertical, then it was rolling left badly, so ended up putting in lots of right aileron trim. I was fairly happy with it flying more or less level by this point, but it was sluggish and really wouldn’t turn right. I was holding in full right aileron and nothing was happening. I kept increasing right aileron trim, which did help, but it needed more movement. Landing was interesting, as I lined it up to run past in front of us, I realised I needed to correct to the right, nothing happened and I elected to add power to go directly over our heads and go round again. The landing on the next circuit was perfect. The owner then added more movement, I took it up again and handed it over to him. It flew perfectly after that and he had a few more flights on his own. I was really impressed at how well it would glide. Although I called it a “Bixler” earlier, it might have been one of the other clone versions, but basically, it was a Multiplex Easy Star type.

We had two more arrivals in the form of the guy who flew the Witch drone at Halloween last year, who was flying a Mavic. The other was a guy I’ve known for ages, who usually has a Stryker, but this time had a UMX A10. He broke something on the first launch and had to tape it back together, but his one and only flight after that was very impressive. The Mavic had a go at filming my adventures with the Atom, but I think the only footage he would have got was me crashing into the grass at the side of the runway. There were at least two other people flying drones by lunchtime as well, so there was so much activity this morning I couldn’t keep track.

After messing around with the Atom almost all morning, I also had two very quick flights with my RS352, swapping LiPos and going back up without even switching off the transmitter. The time on my transmitter display shows 50 minutes this morning, most of which was with the Atom. So, just to recap, the planes I’ve flown this morning are: UMX Spacewalker, Bixler (Maiden), Atom (Maiden) and RS352.

Anyway, I’ve got about an hour of autogyro video to analyse before my next flight.

 

Daisies

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The wind forecast for this weekend was 8mph and I really wanted to test the autogyro again, but I only had the bike this week. As it turned out, the wind was much stronger than expected, at least for the times when I was flying. It seemed to go calm as soon as I touched down.

Try as I might, I just could not figure out a way of getting the autogyro onto the bike in any way that would see me get it to the field in one piece. I thought I could do it by unscrewing the saddle clamps and removing the wire undercarriage, but that still leaves the mast and tail. In the end I had to accept that it was too big and take the mini flying wing in its purpose bought ruck-sack. At least, that is to say that I bought the ruck-sack and designed the flying wing to fit in it.

When I arrived at the field this morning, the first thing I noticed was that it was full of daisies. I’m not that good on flowers, but there were thousands of little yellow flowers everywhere all of a sudden. You can see what I mean in the picture. The second thing I noticed were two people with drones, standing at either end of the field and me in the middle. They obviously didn’t want to talk to each other, or to me, so that’s fine. One of them seemed to be flying FPV like a complete nutter anyway.

Very soon after I arrived, a guy I’ve known for a long time turned up with his son, an F18 and an SU27. Both were made out of depron, but the SU27 was a very light profile model. The F18 had notably better performance, very fast and able to climb vertically in a sustained manner. That’s not to say that the SU27 was a lot slower, but it was lighter, less powerful and had a very draggy airframe by comparison.

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When I did finally get around to putting my wing together, I had the usual problem of trying to figure out where to put the battery to make it balance (NOTE: mark it inside the fuselage this time). I think the combination of wind and slightly rearward C of G lead to a very interesting first flight as it was best described as skittish. I was a bit worried that the motor shaft was bent from the last outing, but this wasn’t evident. My nerves were really on edge after the first 10 minute flight, but I still went up a second time and had another 10 minute flight with the C of G a bit forward, which was a bit less on the ragged edge. The glide isn’t too bad, but there didn’t seem to be any big thermals around, despite my trying to sit under a big, threatening looking, black cloud which was blocking out the sun.

Two flights is usually about all I can manage with this aircraft, before I decide not to push my luck any further. Maybe I’ll try making some modifications to improve the performance, because it’s been a bit of a work in progress for the last 10 years or so? We had an interesting discussion about LiPos puffing up and storage charging while we were comparing the eBay LiPos in the F18 to my Hyperion ones. Apparently, it’s supposed to be 43% with a balance charger, not the 80% I’ve been storing mine at. After the mini wing’s flight, we had a look at the remaining capacity of my 3S 1100mAh pack with a battery checker and it reported one of the cells as 0.5V! Although it looked like a different version of my own battery checker, which I left at home, this obviously couldn’t be right. Either that, or one of my cells is dead. It turns out that not all battery checkers are equal, as all cells from both the packs I used this morning checked out at between 3.6V and 3.8V, so they’re fine. This is what I suspect about the puffing up problem, though. I think the balancers can measure the cell voltages wrong due to bad connections, thus over charging the LiPos which are then stored for a week, or several weeks if I’m really unlucky with the weather.

As I was going home the couple with a Mavic and a pop out landing circle arrived. They also set up about 20 metres away, so obviously didn’t want to talk to us.

OK, so I’m off to put the wheels back on my autogyro and see if it’s windy enough in the back garden to get the rotors running fast enough to feel them lifting. Let’s hope next weekend is sunny and calm.

Autogyro Musings

There’s a cycling event on this weekend and all the roads are closed, so I can’t go flying today. The weather is also extremely windy, so I don’t know if I would have actually tried flying in these conditions? It’s a day for big gliders which like the wind, as I can see lots of development happening in the clouds as they’re being blown overhead. I probably would have gone flying if I could, but I wouldn’t have risked the autogyro.

On the subject of autogyros, I’ve been reading the modelflying thread on the Atom build to try and get to the root cause of my problems. When I finally got to page 20 (there’s a lot of information there), I read about somebody else having problems with it rolling left on take-off. The reason is given as “insufficient rotor speed”, which is what I had suspected. Now, interestingly, there’s also a bit on hand-launching autogyros and they include a link to the very same YouTube video I mentioned last week. My problem stems from the bumpy nature of the grass I’m trying to fly from, so I either need bigger wheels, or I might have to bite the bullet and throw it. I still need to do some more experiments outside in the wind to see how fast the rotors can be made to spin. In the hand-launch clip, it’s stated that, “you should be able to feel the lift pulling it out of your hand”. I never felt that it was producing as much lift as I would have expected, so that needs some more testing. Hopefully we’ll achieve some air under the wheels in the not too distant future?

I’ve also been looking at the videos I took the week before last, both of the autogyro test and of me flying the RS352. The autogyro test doesn’t show very much, as all I can see is it whizzing off into the distance and it disappears into the grass because of the low camera angle. Watching three flights with the RS352 was interesting with the camera pointing up into the sky and the wide angle fish-eye lens of the GoPro Hero 4 Session camera. The first thing that struck me was, “I don’t remember the sky looking quite so dark and threatening”. It looks like there’s about to be a thunderstorm and you can hear the wind whistling around the microphone. These are the conditions we seem to have to fly in these days. The second thing is that the fish-eye effect is great for showing the area I’m flying in, but I have real difficulty working out what the aircraft is doing. I can’t tell the orientation and height, even though I can see myself standing there flying it. The Cuban Eights are fun to watch though. I might have a go at editing this and posting a flying video if I get the time, as this is the best I’ve managed to produce so far.

Let’s hope the August weather is a bit more co-operative than July and that we get some calm conditions for an autogyro test next week.

Post Autogyro

The weather wasn’t very good this week, so I didn’t get to do any flying. The forecast was for heavy localised showers and, right on half past twelve, it rained. A lot. I might have got wet, or I might have got lucky, but, either way, it was just as windy as last week. If the weather had been calm, then I would definitely have had another go with the autogyro, but there didn’t seem much point with the weather like this.

I’ve been looking into the problems with the autogyro and come to a number of conclusions. Firstly, the video I captured was rubbish and didn’t tell me anything. If I try that again, then I’ll have to get the camera higher up. The next thing is that I don’t think I got the rotors up to flying speed as everything I’ve read says that there is a characteristic “whirring” when this happens. It’s supposed to take off at walking pace, which I achieved, but I think there might be something wrong with the rotor head. I went round all the factory fitted bolts and discovered that some of them were quite loose, which was causing a lot of play in the head. In addition to this, I’ve been reading the “Cruiser” autogyro build article from the November 2015 RCM&E, which is basically the same design as the earlier Atom. There is also the larger “Panther” autogyro article from the Model Flying Workshop Special, published in 2015, which contains all the original articles which were serialised in RCM&E from March 2013. These all contain basic instructions on the design of the head and how to test fly an autogyro. However, while they advocate short hops to ascertain the trim, I’ve seen a video on YouTube where an Atom was hand launched in almost gale force wind. This is something I’d never seen before, but you can apparently hand launch an autogyro very easily: https://www.youtube.com/watch?v=OdrfQxKu1Ik

This video is also interesting, as it suggests that the left wheel sticking to the ground is normal and that you can power on past it: https://www.youtube.com/watch?v=9OVpcZOvsOs

If the camera I was using had worked, then this is a carbon copy of my experience last week, except that I wasn’t brave enough to get it into the air. After some playing around on the ground, my feeling is that the left wheel coming up last is due to the anti-clockwise direction of the main rotor.

This is the other hand launch video of an Atom that I found: https://www.youtube.com/watch?v=5bVkgLwmBAc  I’m just not sure I’m that brave.

Anyway, I’ve checked the balance by measuring the hang angle using some rulers and a bit of trigonometry. By my calculations it’s 18.5 degrees, which is spot on. I’ve also modified the 0.8mm shims on the underside of the rotor mounts as they were getting caught every time the blades got tangled up last week. I’ve now lengthened them and covered over them, but I suspect that this might be where my problems lie. When I spin up the rotors on the ground, I just don’t feel like I’m getting much movement of the air. Now, the HK head has a known problem in that it’s constructed upside down and shipped in a state where the rotors would give no lift (souce: modelflying.co.uk Atom build thread). I took it apart as directed, fitted the fibreglass triangle to replace the plastic one which breaks and rebuilt it the other way up. I’ve added the shims as instructed, which put the blades at a more negative alpha and aid in spinning up the rotors. I’m not convinced that this is right, though, so I’m going to do some more investigating before I try and fly again.

That’s it for this week, but work is taking over again, so I’m not sure how much I’m going to be able to do on the autogyro. I’ve got this close to getting it in the air though, so I’m not going to give up now.

First Autogyro

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I was determined to test fly the Atom autogyro this weekend and I finally managed to get everything together. I don’t know whether this is the first autogyro that’s been flown at this site, but in all the years I’ve been flying here, I’ve never seen another one. I also don’t know whether this counts as a flight, because the left wheel never actually left the ground, but this was my first attempt.

My first flight of the morning was with somebody else’s UMX Champ. Weighing only about 35 grams, this was probably a stupid idea in the steadily increasing wind, but I’ve flown it perfectly well in windy conditions before. This time, though, a gust flipped it upside down and I crashed into the ground. I was able to partially rescue it, so there wasn’t much impact and it was undamaged.

Then I put the rotors onto the autogyro and had run out of excuses for not flying it. Although, it was a close call as the wind was way above the recommended “light winds” stated in the magazine article for the first test flight (RCM&E Autumn 2015 Special). I was determined to give it a go and try running it along the ground and “hopping” when the rotors began to lift. The rational behind this is to trim the head angle, but I didn’t have much luck. I had the foresight to take a GoPro Hero 4 Session camera with me and record the flights so I could watch them back later, but I had it in the wrong mode for the first set of flights and only ended up taking stills. I really don’t like that camera, but I had lent my preferred RunCam to somebody on Thursday.

As far as the test “hops” went, the rotor would spin up fairly easily in the wind, but I’m not convinced I was getting up to full flying speed before running out of runway (for “runway”, read “patchy bit of bumpy grass”). I wasn’t able to steer effectively with the rudder and it seemed to be yawing to the right. When it did start to lift off, the left wheel seemed stuck to the ground and it wanted to roll over onto its left side. I thought this might be a head trim angle problem, so I progressively added right aileron trim, up to the point where I had 15 clicks right trim and there seemed to be no difference, even when holding right aileron while it ran along the grass. The airframe is impressively resilient though. I had it tip over on its left side numerous times and tangled up the rotor blades, but it still went home in one piece. I think that, in all the years I’ve been flying, maybe I’ve learned how to crash well?

After resting the autogyro for a bit, we then had another go with the Champ. This time it went really well, much more like I would expect, so either the wind had eased off a bit, or it was just less turbulent than before? However, while I was flying the Champ, the Atom got blown over onto its side twice, tangling up the three rotor blades again. Luckily, there was no damage, but, with its three rotors now attached, the wind was causing them to spin very fast, resulting in it tipping over. I would have said that it was at flight speed at one point, they were spinning that quickly in the wind. Seeing this happening, I brought the Champ down for an almost perfect landing and rushed over to the Atom with the transmitter still in my hand to assist the owner of the Champ who was trying to figure out how to stop the blades. This confused him completely as he missed my landing and thought his aircraft was still in the sky. Anyway, still no damage to the Atom or Champ. The RS352 tried to take off on its own as well, but it’s fairly indestructible. I’m starting to think that maybe this wasn’t the best day to test fly an autogyro?

At this point a couple of guys arrived with a chair and a drone and proceeded to sit right where I had been doing the Atom test hops before. I’m not sure where they were from, but their English wasn’t great. There was also another drone flying right up the far end of the field, ignoring us completely. This was an East European couple and their son, as the lady did come over to us later on to borrow a screwdriver to change the battery in her son’s mini drone.

OK, so having had a think about the autogyro, and with the wind lessening a bit, I had another go. This time, though, I managed to get the camera in the right mode, so I’m hoping there should be some video there for me to review later. This went the same as before, trying various directions into wind and trying to get forward speed and rotor speed for flight. Along the ground it was yawing to the right if the rotors were spinning, but tracking more straight if the head didn’t spin. The ground handling wasn’t good enough to to keep it in a straight line along the runway I was now using, which was almost directly into wind, but narrow and with stubby grass either side. I kept ending up in the grass to the right. Moving to another area didn’t really help as the aircraft would never pull its left wheel off the ground. In the end I gave up, which was very disappointing. I would have taken any sort of air under the wheels, even millimetres. So, to review, rotor spinning means yawing right on the ground and left wheel won’t unstick despite extreme right tilt and good rotor speed. I need to go away and do some research for next time.

After that I had 3 flights with the RS352, which loved the conditions on its new batteries. I had one of the older batteries (3S 1100mAh, 18 months old) in the Autogyro, which showed 50% full when analysed after the test flights. The other one I flew in the RS352, but it just didn’t have the punch of the newer cells. As I had the GoPro set up anyway, I decided to point it at a patch of sky and film myself flying the RS352. I don’t know what footage I got yet, but maybe I got something good with the wide angle lens?

While I was flying the RS352, we had another person arrive with a drone who I’ve never see before. She also wasn’t like all the other drone flyers as she knew what an autogyro was, even if she didn’t know the English word for one. My guess is that she was East European from her accent, with bright red hair and a mini drone which she had constructed from bits herself. It was a bit bigger than a 100 size (but not by much) and had tiny brushless motors and FPV. Unfortunately, she had forgotten to charge the goggles, so couldn’t fly with FPV and didn’t feel confident enough to fly with line of sight because of the orientation. She apparently files bigger drones too, but she obviously knows what she was talking about as we were discussing why neither of us would do some of the stupid things the other guys were now doing with their DJI Phantom. After that a husband and wife also turned up with a Mavic, but I had to go at this point.

That was quite an eventful day of flying, so now I’ve got to go away and do my homework on autogyros.

Funny Old Weather

There was a forecast of sunshine and 8mph winds this morning, but it seemed more like a 15mph wind sneaked in when nobody was looking. It was an odd sort of day where, one minute the Sun is burning you through the back of your shirt, then great big black clouds came over looking threatening. It never actually rained, but the occasionally overcast conditions and breeze made for a cool respite from the relentless heat.

The first flight I had this morning was with a Radian electric glider, which the owner also flew himself on a couple of occasions during that one flight. There were already two people there when I arrived, one flying an Inspire while the other was watching the FPV from under a cover. There was also another guy with what looked like a Mavic drone flying from about 20 metres away, not wanting to be friends with us. Later in the day we also had one of those moments when you say, “if we’re all here, who’s that flying a drone above us?”, then realised that there was a guy standing at the very edge of the field with a transmitter. In addition to the two anti-socials, we also had two regulars with a Nieuport biplane, Ripmax Transition VTOL and a small quadcopter.

In addition to the Radian and 5 flights with my RS352, I also tried out some FPV with my 3D printed micro quadcopter. This was a bit of a last minute addition to the kit this morning, as I just threw all the bits into my bag as I was leaving, but it was certainly worth it. I’m not a big fan of FPV, but it was quite fun to fly the 45g quadcopter in circles around where we were standing. Looking back at myself through the eyes of the aircraft nearly made me fall over, but you soon get the hang of it. Judging speed, distance and height is very difficult because of the camera’s field of view. You always look like you’re doing about Mach one over the grass because you’ve suddenly been shrunk down to the size of a bird. I still think doing slow, lazy aerobatics with the RS352 is a lot more fun, but I’ll give the quadcopter another go in its natural habitat – indoors around the furniture.

All in all, it was quite a good flying session this morning. I would have been annoyed at not being able to get the autogyro ready to test fly if it hadn’t been for the wind. The forecast was perfect for a test flight, then a rather hectic week at work took its toll and I couldn’t get the aircraft ready in time, then the conditions turned out to be rather less than perfect. Having spent so long building it, there’s no point in rushing into a test flight in the wrong weather conditions. During the week, I discovered that it’s actually a lot harder to get the blades to attach to the head than I realised. I’m also going to have to do some further reading about the various “shims” people have added to get the blades at the right alpha to generate lift. Then I need almost dead calm conditions to do some runs up and down the runway. Anyway, I’m off to do some reading about autogyros and I might even try and write a simulator to practise flying one – that’s something I’ve never seen. Here’s to next week’s weather and an easy week at work.

Only Me

I thought the weather forecast was for heavy rain to clear early on, leaving a dry day with 10mph winds. When I looked out of the window this morning, the anemometer on the house over the back was spinning like a crazy thing. It was just as windy as last week and bright and sunny with it. Obviously the gale force wind had blown all the clouds away, leaving a clear blue sky and 25 degree sunshine. This is precisely my least favourite type of weather, because it looks like a nice day to go flying, but you know you shouldn’t.

I went flying anyway, working on the basis that the wind would decrease throughout the morning. It didn’t, so all of the four flights that I had with the RS352 were a bit hairy. When I tried any sort of aerobatics containing a vertical manoeuvre, the aircraft got blown about 10 metres towards me. In the end I decided to try and solve the problem I’ve always had with this aircraft, where outside loops go completely screwy. I know, trimming an aircraft in 20mph winds isn’t recommended, but I tried a couple of clicks of left rudder to see if it helped straighten the loops. From inverted, it makes no difference, but from the right way up, I think it does help leave the nose pointing in the entry direction on exit. I’ll have to work on this when there’s no wind, but I noticed that my current trim has the ailerons almost exactly level with a small amount of right rudder. It does seem to have a much more central trim than before, which might be due to the motor change a while back. Swapping out all the servos at Christmas must have had an effect too, but you wouldn’t expect the control surfaces to be in a different position, just the servos in a different position to achieve the same control deflection. Whatever the reason, I now seem to have a more balanced trim than before. So, why does it roll horribly on the initial quarter of an outside loop? I need to investigate this a bit more.

Anyway, I had an interesting conversation with the man who collects the dustbins, as it turns out that he used to fly here many years ago too. I thought I was going to be on my own for the whole morning as nobody else was stupid enough to fly in the windy conditions. Then, right at the end, a guy with a camera came over and sat on the bench. It was only after talking to him for a while that I realised the rucksack he was carrying was the DJI Mavic one. Sure enough, he had a Mavic in it, but initially didn’t fancy flying it in the wind. I had to leave before seeing it fly, but I’m fairly sure he got it into the air, so it wasn’t only me flying this week.

On a drone related note, I also got my 3D printed micro FPV drone to fly during the week. I managed to get the FPV power lead soldered on and gave it a go in the house. This is using the F3 EVO Brushed controller and my Futaba transmitter, so it’s much more professional kit than the HubSan’s we’ve been flying. Even so, it was very hard to achieve a stable hover, although I could fly it up and down the hallway and through the doorways quite easily. More practice is needed I think.

Finally, the ATOM Autogyro is almost flight ready. All it needs is a final control check, some bolts for the blades, keepers tightened up on the head and a way of holding the canopy in place. I’m thinking tape for the canopy and everything else is just tightening things up. I had wondered whether this week would be a good week for a test flight, but I’m glad I rejected that idea. What I need now are clam conditions so I can run it up and down the runway to get the head sorted out before committing to the air for the first time.

Unsettled Weather

At 8am this morning the wind was already blowing the trees around and making the neighbour’s anemometer go crazy. I would have been on the bike this week, so I decided to stay indoors instead. I’m a bit annoyed with myself for not going flying, but I wouldn’t have got much actual flying in because of the weather.

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Instead of flying, I thought I should finally have a look at the 3D printed “Whoop” frame that I’ve had on the bench for the last few months. As always, I underestimated how hard it is to get all the electronics and wiring into such a small space. In the end I cut up another failed 3D print and glued the extra bits onto this one to make a base underneath. This will allow me to fix the flight controller with double sided foam tape and also attach the battery underneath. The FPV camera can go on top. The sellotape in the picture shows where I’ve glued the new bottom piece in place. The PLA material used in the 3D print can be a bit temperamental with cyano, so I’ve left the tape in place for now. With a bit of luck I’ll get it all working later and be able to fly it around the house.

Also, last night I made some final changes to the rudder control rod on the ATOM Autogyro and glued it in position. This now means that all the control surfaces work and I just need to do the final tweaking to make it flight ready. Could it really be that I’ve finally finished it? I’ve only taken about 2 years. My thoughts now are whether I can build an autogyro flight simulator as I’ve never seen one? It looks like I might just have to test fly it the old fashioned way.