Staight line flying

thoneter · Sep 30, 2017

I'm sure most are going to wonder what drugs I'm doing on this one but here it goes. I have been trying to fly straight down the center of a railroad track. The wind is not a factor. If I try and keep it centered the left and right movements are jerky. The longest straight flight thus far is 20 seconds but the H usually drifts within 2 or 3.

I've gone in and adjusted the rates and it doesn't make the movements less pronounced. I have not shut off GPS as I've got bushes and trees near the track and don't want to visit them! Below is one of the vids of me going slow. Faster is easier to reduce jerkyness but then it introduces more likeliness that I'll visit a tree!

I've just reduced the J2 speed to slower to see if that helps with the jerkyness. The only other thing I haven't tried is flying sideways to see if that reduces drift and jerky corrections.

Here's a video of flying pretty straight at a distance up to 300 feet.
Any suggestions are appreciated. Steve Carr suggested CCC but the trees and bushes concern me on that option. Thanks in advance Terry Thone

Thanks for the feedback. I'm always looking for suggestions to get over issues. I appreciated the feedback that has been given. Do you guys think that upping the speed of the lateral movements on the channel settings would help? I've done the broken line option in channel settings and reduced the settings so that the stick movements suppose to be more subtle but I don't see any difference in the real world.

gwhuntoon · Sep 30, 2017

Looking at the pole in the distance as a reference the H appears to be flying straight, it looks to me like the tracks are curved which makes it appear as though the H is vectoring away.

grandpawmoses · Sep 30, 2017

While I agree with gwhuntoon about the illusion because the tracks are curved, you are also flying close to those steel rails which may cause an issue. I'd try a test flight in an open field and gauge it's ability to fly straight there.

AH-1G · Sep 30, 2017

I had the same issue 3 weeks ago at a rail track, it's the steel causing it to drift.

NorWiscPilot · Sep 30, 2017

The flight is exactly as I would expect. Aside from any "interference" from the tracks themselves, what else could be expected by trying to track curved tracks? The pilot is in control as to the corrections necessary to stay within the lines.

Ever see an illustration of a vehicle traveling down a highway? It feels like we're driving in a straight line, but in actuality we are drifting side to side quite a bit, subconsciously correcting the direction. And that is with direct control (hands on the steering wheel). Even more of a challenge when we have to remotely correct something based on what we see on a screen. (By the way, I have NEVER mastered those video race games; the sit in the cockpit type, let alone the joystick ones.)

The only way I see to check the stability the OP is looking for, in my opinion, is to find "straight" tracks, plot a curved cable cam mission, point to point, and see if it tracks the tracks better than human control.

Just sayin'!

Jeff

PatR · Sep 30, 2017

My experience in trying to fly down the middle of RR tracks, low to the tracks, has consistently provided an aircraft reaction where it will initially drift from side to side a little bit but after bout 150' or so it will break sharply away from the tracks to one side or another. I don't have an absolute cause of this but I suspect it has a lot to do with being too close to steel RR tracks. The further away from the ST-16 the worse it gets. All my flights were done over very straight RR tracks, a little higher than what is shown in the video, and no fingers on the right stick after starting the H on course. Yours did better than mine has that close to RR tracks.

thoneter · Sep 30, 2017

gwhuntoon said:
Looking at the pole in the distance as a reference the H appears to be flying straight, it looks to me like the tracks are curved which makes it appear as though the H is vectoring away.

It drifts before the track curves. I adjust and it drifts again. I've got other vids that the H doesn't drift as much going down straight track. Just wanted to see if anyone is able to fly down a straight pattern without so much joystick input

thoneter · Sep 30, 2017

NorWiscPilot said:
The flight is exactly as I would expect. Aside from any "interference" from the tracks themselves, what else could be expected by trying to track curved tracks? The pilot is in control as to the corrections necessary to stay within the lines.

Ever see an illustration of a vehicle traveling down a highway? It feels like we're driving in a straight line, but in actuality we are drifting side to side quite a bit, subconsciously correcting the direction. And that is with direct control (hands on the steering wheel). Even more of a challenge when we have to remotely correct something based on what we see on a screen. (By the way, I have NEVER mastered those video race games; the sit in the cockpit type, let alone the joystick ones.)

The only way I see to check the stability the OP is looking for, in my opinion, is to find "straight" tracks, plot a curved cable cam mission, point to point, and see if it tracks the tracks better than human control.

Just sayin'!

Jeff

I completely agree with your assessment of going down the road. I owned a salvage yard for 20 years. We had a wrecker that would lift the whole car, tractor, combine etc completely off of the ground. With this weight behind the wrecker it would going down the road in a straight line without vast corrections impossible.

You are right. We put in minute steering corrections all the time. My issue is the corrections are abrupt and jerky. I thought the rate adjustments would make left and right adjustments more fluid and less abrupt.

thoneter · Sep 30, 2017

PatR said:
My experience in trying to fly down the middle of RR tracks, low to the tracks, has consistently provided an aircraft reaction where it will initially drift from side to side a little bit but after bout 150' or so it will break sharply away from the tracks to one side or another. I don't have an absolute cause of this but I suspect it has a lot to do with being too close to steel RR tracks. The further away from the ST-16 the worse it gets. All my flights were done over very straight RR tracks, a little higher than what is shown in the video, and no fingers on the right stick after starting the H on course. Yours did better than mine has that close to RR tracks.

I've got some flight where I go straight for 20 seconds but it was when I was going faster and farther away from the st16. So I know many are stating the steel is interfering but I have my doubts as even when I fly high it has the same results. In my opinion it's like being up 400 feet and moving at full throttle. All distant subjects are stable and the movement appears less abrupt.

My guestimation is that the tracks just enhance the lateral movements. Much like the moon appears twice it's size when near the horizon. But who knows my wife occasionally tells me I could be wrong.

Ty Pilot · Sep 30, 2017

Aside from the tracks creating interference that causes the craft to drift; trying to correct forward flight with the right stick (aileron) while maintaining a constant speed is difficult (with the H), even for very steady handed pilots. Instead, use the D pad cruise control to move the craft forward at a steady speed then use the left stick, (rudder) to stay on heading. This will allow you not only to separate the control input but allows you to focus solely on direction while forward speed is maintained by the craft.

thoneter · Sep 30, 2017

Ty Pilot said:
Aside from the tracks creating interference that causes the craft to drift; trying to correct forward flight with the right stick (aileron) while maintaining a constant speed is difficult (with the H), even for very steady handed pilots. Instead, use the D pad cruise control to move the craft forward at a steady speed then use the left stick, (rudder) to stay on heading. This will allow you not only to separate the control input but allows you to focus solely on direction while forward speed is maintained by the craft.

Thanks for the cruise control suggestion. I'm not having rudder issues as the rate adjustments appear to work for that. It's trying to stay centered on the track with the right joystick and doing it fluidly. The cruise control may help with that and I'll give it a shot. Maybe with the right stick centered the lateral adjustments may be more fluid.

Ty Pilot · Sep 30, 2017

Understood. It looks in the video that you are using the right stick to keep the craft over the tracks, and that is where some the jerkiness is coming from. What I am saying is to use the rudder (Instead) to steer the craft as you can make direction changes far smoother than trying to direct left and right with the right stick. And as I mentioned the tracks are going to pose a problem that may be difficult to get a perfectly smooth shot but just as a general rule of thumb; to get a steady smooth shot, where you want to stay on course or have direction changes, the rudder will give better results.

thoneter · Sep 30, 2017

Ty Pilot said:
Understood. It looks in the video that you are using the right stick to keep the craft over the tracks, and that is where some the jerkiness is coming from. What I am saying is to use the rudder (Instead) to steer the craft as you can make direction changes far smoother than trying to direct left and right with the right stick. And as I mentioned the tracks are going to pose a problem that may be difficult to get a perfectly smooth shot but just as a general rule of thumb; to get a steady smooth shot, where you want to stay on course or have direction changes, the rudder will give better results.

I understood the jist of your reply. I wonder if there are aerodynamics for this left and right slip that I'm overlooking.

PatR · Oct 1, 2017

More a left and right slip of the thumb. The ST-16 is quite sensitive to roll around center stick. It's why the D pads work better for straight line flight.

BobW55 · Oct 4, 2017

I also think your vantage point is coming into play. Looks like you are standing off to the sides of the track, the further away the H gets, the more your perspective is skewed. If at all possible, stand in the middle of the track, see if there is a reference point/land mark in the distance you can use to gauge your flight path.

R12NDS · Oct 4, 2017

It will make a nice video, so if it was me i would hold the Typhoon and simply walk down the track. At that height, you dont need an airborne camera...if you have an action grip use that.

Never done it...but i think its worth a go?!?!?!

Satguy2235 · Oct 4, 2017

As a former railroad employee - - the public is normally unaware that the railroad has control signal on most rails - - Signal & crossing functions. Possibly this is an issue for you. Railroads don't publish this information as the signal does not radiate far from the rails.

John Dube · Oct 4, 2017

Back to CCC. Try programming a CCC route, from point A to point B, but use a higher altitude for the test to avoid the trees, brush, poles, etc. Once you have it flying the straight line over the tracks at the higher altitude. then adjust the altitude in the CCC route and drop it down to the altitude you want to film. Since it will be flying CCC, you should not get the drift.

Michael Brown · Oct 4, 2017

The CCC is the best way to guarantee a nice straight move along tracks. Even curving tracks. The other option is learning to fly your craft. With gentle nudges you can slowly adjust the flight to stay on path. It's taken a year for me to master flying in a straight line without CCC, but it can be done.

Swampraton · Oct 5, 2017

Each rail has an electromagnetic field. Like a long wire. There are convergent fields that vary with length. In fact the railroad use the rails for signal transmission. Try using a compass close to the tracks and you will see how it varies. The more altitude the less interference.