Tag Archive: hovering


Hello!

I had quite some pause in my RC activity. My daughter had priority over RC stuff, so please excuse my lack of posts.

Now the indoor season is going, so we can join in a school sports hall on Friday evenings for one and a half hours.

Outdoors flying is probably getting very problematic in the future, our club is being kicked out from our flying field by the municipality. Unfortunately there is quite some politics and corruption involved, so we don’t really have much of a chance in this game.

My 10th flight was rather boring probably. I haven’t been flying for quite some time, so I tried to freshen up my reflexes.

My latest indoor flight was the 11th flight with my Extra300. I used a new camera for recording, purchased recently an SJCAM SJ4000 action camera. It is basically a copy of GoPro3, with some attractive pricing.

The camera is rather okay for my application. I knew that it has some limitations, so I was not expecting it to beat the latest GoPro4 series. For instance it has some issues with white balance and it would not work so fine for FPV either. It cannot do 60 fps, only 30 fps. But it is fully compatible with GoPro accessories and has a rather okay picture for the price. I made some very simple reviews of it, you can find some videos below.

I look forward to fly a bit more during the winter season.

With best regards,

Sir Crash a Lot

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Hello,

It was quite some time since I reflected on my Extra300 EPP indoor plane. The build was rather long and I had many questionmarks. I think this happened partly due to my inexperience in building and due to the manual being written by a very experienced senior pilot who mentioned only the most important aspects of the build. I am not even novice in building, so I would have needed a lot more detail in building instructions.

Anyhow, the plane is ready and it flies well. I tried to take a stepwise approach with flying. I knew that indoor flying would demand constant usage of rudder. While flying my Easystar I started to turn with rudder and aileron together. So I made some rudder practice to prepare myself for indoor challenges. However I knew that playing with rudder while having “the whole sky” to my disposal is rather easy. I was prepared for some crashes as I knew that indoor will be a lot more difficult.

To not ruin the plane within 10 seconds of flight I tried to practice on the ground first. That said applying a fraction of throttle and “driving around” in circles rather than lifting off. This was more difficult than I have thought it would be, since nothing was trimmed and I had a new radio system even. As result I had some occasional unintended takeoffs. These were aborted mostly, that said I crashed the plane nose-in to the floor. Like a warbird tip. I consumed propellers at some rate 🙂

Maiden flight:

2nd flight:

3rd flight, I started to enjoy high angle-of-attack slow passes. Not easy, but fun. Tried to mix directions, figure 8 and slalom flight. Very exciting to do, maybe not so exciting to watch, though.

4th flight, I tried to transition to hover.

5th flight, with hovering practice.

6th flight, more hovering and fun flight.

7th flight. I started to grow devil horns, had some “moments” of daredevil actions. Landed on the wall for instance.

8th flight, my first roll indoors. Scary but fun.

I skipped last weeks flights as I was fortunate enough to have my daughter born. She was born at 1:30 on the 20th of January 2014. A real miracle, 49 cm and 3230 grams of new life. Funny enough it is my birthday, I received the best possible present ever! I stayed home to help my wife and the baby, no flying right now. I will regain action soon, just need to sort out the first few weeks with helping around.

I am not sure what will happen to our outdoors flying. The flight club is going through a very difficult time period. The council announced that they will remove us from our flying field. As from 1st of February 2014 we are no longer allowed to use the field, we have to clear the area and cannot return. We haven’t received yet any other area to use, so the very existence of the club is in danger.
Our flight club and cross motorcycle (dirt bike if you like) club is removed from the area. The cause for this unfortunate decision is that an investment group tied to some politician tries to build a set of luxury golf flats in the area. It is rather interesting, since the golf club itself went bankrupt several times during the last few years. Besides that there are many issues around the build plans, as it seems politics and corruption got mixed up things quite a bit.

The club tried to apply for a negotiation, but the council does not really listen. So as for new it looks like that 1st of February is the end of our current flight activity.

I don’t know yet how we will do. There are some locations where I can fly, but the club itself will not be able to survive without a flying field. We will see.

An article from local newspaper.

With best regards,

Sir Crash a Lot

Hello!

We are in April 2010 at this point. I see more and more interest in recording my flights, I try to document them. I discover growing attraction in recording the flight and also from the aircraft if possible.

That is actually how I got my attention locked to FPV, gradually tried to enhance my recordings.

At this point I only had my wifes camera, a point and shoot digicam. I tried to record from the ground in last post. Then from a chair. These were fun, but I experimented further.

This time I wanted to record hovering from close. As the rotor blades are spinning it is difficult to record close hovering from a chair or tripod. So what if I have the camera close to the ground but it would point upwards? I tried this.

I had some luck with weather and part of this recording is happening outdoors. It was very tricky to fly outdoors. The location is close to the sea, there is a lot of wind there. I am standing between workshop building and a truck parking lot. Wind can pick up speed there, plus there is a lot of turbulence in form of wind gusts. They are invisible on the recording but can actually slam the heli into the ground. Very scary for a newbie pilot as me. In same time great training.

I really liked those shots when you see clouds and the heli hovering close. The camera has 28 mm wide lens (equivalent 35 mm film format), so it can record nicely.

I managed to land onto the camera, knocked it over some times. Later I moved indoors and tried some other landings and hoverings. Looks nice to me. 🙂

From this point I had a mission: record as nice videos as I can (plus fly my heli).

Best regards,

Sir Crash a Lot

Hello!

I am telling story about a challenge that I created for myself. It happened in May 2010.

As weather was rather challenging here I was forced to have indoor activities. I am lucky to rent a flat with a glassed balcony. This means that I can fly in severe weather conditions even. It was raining outdoors but on the balcony I was not disturbed by this, could practice hovering and landing.

To improve my skills I built a simple exercise track. It consists of 3 crate boxes, they simulate buildings. Like in action movies, when the pilot lands on a skyscraper and the secret agent penetrates defense. Or something similar 🙂

As I had 3 boxes I tried to have 3 different levels of difficulty. Easy, medium and hard level. Why is a box more difficult? Because of turbulence. As I described in my previous post turbulence can be a serious factor when hovering close to objects.

As the balcony is rather limited in area walls are close. I deliberately placed my boxes close to the wall, so I had to cope with turbulence. You can see how I succeed. In some cases turbulence is so strong that it actually sucks my heli to the wall. I have full lock on the stick and the heli is hardly moving away from the wall. Quite challenging indeed.

You can see that I have a camera perspective that is rather dynamic. I made myself a so-called camera hat, I will try to describe that later. Idea is to have a simple baseball cap and mount a camera onto the shield. So that where you might turn your head your camera will record roughly the same. Advantage is that you can move around and don’t need your hands to hold the camera. You can buy such hats but I made one instead.

Best regards,

Sir Crash a Lot

Hello!

In my last post I described how I managed with simple hovering and landing on table. This post is also the past, what you see happened in February 2010.

Now it is time to do some figure flight. It is a major step in my helicopter career, I shall explain what is so important here.

As you can see I fly in living room, same location as previously. What is different is how I fly. The heli does an “eight” and some rounds. This is a big step forward.

When you start learning heli flying you will start with hovering and basic flight. This is rather easy as long as the tail of the heli is pointing at you. Why? Because when you push the joystick to the left on the controller the heli will move left. As long as the tail points at you the nose of the heli will look the same direction as you (the pilot) are looking. Easy.

To get some science into this let’s talk about coordinate systems.

In a 3D system you have 3 coordinates, or 3 axis if you shall say so. X, Y and Z. You can have these as you want but for easier understanding we consider:

– X is forward,

– Y is to the sides

– Z is vertical

On your transmitter these will correspond to various stick inputs.

On a Mode 2 transmitter left joystick will control Z-axis, right joystick will control X- and Y-axis. (I made it simple now, on left stick you also have yaw that will interfere with both X- and Y-axis.)

How will this look like if we apply our coordinates to the heli?

Now let’s try to imagine these two coordinate systems in relevance to each other.

When you do tail-in hovering (nose of heli pointing where your nose is pointing) X of heli will match X of transmitter. Same with Y and Z.

If you do side-in hovering (nose of heli pointing 90-degrees left or right) X of heli will correspond to X of transmitter. Where is the catch then? You will percieve that when heli moves “to the left” that you need to add stick input corresponding right. But this will not work well, since heli is actually traveling forward (its own X coordinate) and you need to add backwards input (transmitters X coordinate), not side (transmitters Y axis). If you take a look at my first flight you can see that I was fouled by this. The heli kept rotating, it went all over the place, I had not a single clue how to gain control. I could not keep track of the helicopters coordinate system in short.

What is the solution? You need to keep track of the nose of your heli, this will give you correct control.

Mikey’sRC has a great tutorial on side-in hovering. Please check it out, this will give you a nice explanation.

He has another tutorial about nose-in hovering, a good explanation in graphic nature.

What is to be told of my flight? I crash at the end of it. Several times. You can see for instance that I get close to the lamp and then crash. I got into turbulence there. What is turbulence?

Turbulence is like a vortex. Depending on what produces turbulence it can be all sort. In the case of helicopters you get a downstream flow generated by the rotor (rotors). As air is lazy it wants to get calm again and escapes to the side. Since this downstream flow is like a cylinder it escapes in all directions.

As the rotors suck air from above and push them down some air recirculates at the tip of the rotors and creates a torus-like flow. Like a donut cake without sugar glazing.

As you get near objects this flow will interact with them and create a suction force. It was long time ago that I studied fluid dynamics, I hope that I don’t get it wrong. According to Bernoulli’s principle as you compress the flow speed will increase and pressure will drop.

So as you get closer with your rotor to the lamp the heli will actually suck itself onto the lamp. As Lama is not a power-house it has limited resources for manoeuvres and after a while you cannot get away from the lamp. It is better to close throttle and let it fall. That is what you can see in the video. I do the same with the sofa once. And once it is just pilot error and crash into the table.

After a while my poor piloting showed traces of destruction on the rotor blades.

So I replaced them. The difference was noticable. New blades track better. This reduces vibration, gives smoother flight and provides better overall control.

As I described in my post earlier you will need some basic tooling for changing blades.

Best regards,

Sir Crash a Lot