Flying an exact radius around a point

birdus

birdus

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Jay Williams
If I wanted to fly a 5nm radius (for example) around a specific point, how would I do that? I imagine the best way would be if Garmin Pilot or ForeFlight had a feature where they would give me a magenta circle of specified radius centered at a specific point, but I don't know if they can do that. Can they? Other ways of accomplishing this?

Thanks,
Jay
 
birdus said:
If I wanted to fly a 5nm radius (for example) around a specific point, how would I do that? I imagine the best way would be if Garmin Pilot or ForeFlight had a feature where they would give me a magenta circle of specified radius centered at a specific point, but I don't know if they can do that. Can they? Other ways of accomplishing this?

Thanks,
Jay
Click to expand...

Go on a day with zero wind.
 
IK04 said:
Draw a circle on a map?
Click to expand...

Over a completely remote area without many landmarks, this could be a challenge. I guess I'd actually need to draw the circle and see if I could find enough landmarks to maintain a constant radius. Would be challenging at best. I'm open to all ideas, though.
 
Without AP, drop a GPS point in the middle and roll into a turn , adjust rate based on distance from waypoint, tighten up if you go over 5.00, loosen up if you go under.

Aside from that probably could import something for the AP to just mindlessly track.
 
James331 said:
Without AP, drop a GPS point in the middle and roll into a turn , adjust rate based on distance from waypoint, tighten up if you go over 5.00, loosen up if you go under.
Click to expand...

No autopilot. Sounds like what Geoff suggested...I think.
 
MauleSkinner said:
Aside from “this is me not touching your TFR!” What would be the use for flying an exact radius?
Click to expand...

I want to fly around Mt. Rainier, taking a photograph every few seconds, then create a VR object from those photos so that one can rotate the mountain and view it from any perspective on their computer. Would be interesting to do for other objects, too, maybe even cities, or parts of cities.
 
birdus said:
I want to fly around Mt. Rainier, taking a photograph every few seconds, then create a VR object from those photos so that one can rotate the mountain and view it from any perspective on their computer. Would be interesting to do for other objects, too, maybe even cities, or parts of cities.
Click to expand...
Can't Google Earth do that?
 
ircphoenix said:
Can't Google Earth do that?
Click to expand...

Sure, if your quality standard is really, really low. I'm aiming for something a few orders of magnitude better than satellite photographs. Of course, I may be the only one who cares, but I'll certainly enjoy the end product, not to mention the process.
 
Yeah, just use a GPS and maintain a constant distance from the waypoint while turning...
 
IK04 said:
Yeah, just use a GPS and maintain a constant distance from the waypoint while turning...
Click to expand...

That seems like the simplest solution. Thanks for all the ideas, everybody!
 
birdus said:
Unfortunately, flying an exact circle would require infinitely many entries and that would take a long time. Other than that, great idea! :D
Click to expand...
But you don't need an exact circle. You only need to be approximately the same distance away every few seconds. And at five miles, unless you're using a super telephoto lens, a few hundred feet either direction probably won't be visible. I'm sure someone could do the math for min/max distance from center for a 30/60/90/120 sided shape.
 
birdus said:
No autopilot. Sounds like what Geoff suggested...I think.
Click to expand...
On something like G1000 I fly with it is really easy. Set your PFD so you get RMI needle pointing to the waypoint and just fly perpendicular to this needle watching the distance which is displayed for you. Adjust the heading every minute or so.
 
No exact, but enter 8 lat/Lon waypoints into you GPS at 45 degrees and 5 nm from the center point as user waypoints. Enter the 8 user WPs into the flight plan and activate. You will get an octagon, fly the map with no straight and level legs.
 
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Lindberg said:
I'm sure someone could do the math for min/max distance from center for a 30/60/90/120 sided shape.
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School Math if it was acceptable to assume a flat earth and to assume that the lines of longitude were parallel. Such as on a Mercator projection map. If you want the real answer there are quite a few promising looking links returned by google search

lat/long for points on a circle
 
birdus said:
I want to fly around Mt. Rainier, taking a photograph every few seconds, then create a VR object from those photos so that one can rotate the mountain and view it from any perspective on their computer. Would be interesting to do for other objects, too, maybe even cities, or parts of cities.
Click to expand...

OK. Your circle is going to be 31.4nm (2πr) so at 90 knots it'll take about 21 minutes to fly, and if you take a pic every 5 seconds you'll have 252 shots. Is that enough?

I would do this, using ForeFlight:

1) Create a user waypoint at the peak on your iPad. Call it RANIER.

IMG_0570.PNG

2) Go into Excel. In the first cell, type "1". Fill down to row 360.
3) In cell B1, type ="RANIER/" + A1 + "/5"
4) Fill down to cell B360.
5) With B1-B360 selected, Copy.
6) Go to your email client, paste, and send it to yourself.
7) On the iPad, go to Mail, open the message, select, copy.
8) Go into ForeFlight. You'll need to put at least one waypoint into the flight plan to start.
9) Tap that waypoint, then "Insert After..." and paste.

Actually, now that I played with it a bit, every 10 degrees looks to be plenty.

IMG_0568.PNG

Here you go... Do the first step, then paste this:

RANIER/360/5
RANIER/010/5
RANIER/020/5
RANIER/030/5
RANIER/040/5
RANIER/050/5
RANIER/060/5
RANIER/070/5
RANIER/080/5
RANIER/090/5
RANIER/100/5
RANIER/110/5
RANIER/120/5
RANIER/130/5
RANIER/140/5
RANIER/150/5
RANIER/160/5
RANIER/170/5
RANIER/180/5
RANIER/190/5
RANIER/200/5
RANIER/210/5
RANIER/220/5
RANIER/230/5
RANIER/240/5
RANIER/250/5
RANIER/260/5
RANIER/270/5
RANIER/280/5
RANIER/290/5
RANIER/300/5
RANIER/310/5
RANIER/320/5
RANIER/330/5
RANIER/340/5
RANIER/350/5
RANIER/360/5
 
Take what you learned in primary training about Turns around a point and apply it to your current 'need.'

Should be easy enough.
 
flyingcheesehead said:
OK. Your circle is going to be 31.4nm (2πr) so at 90 knots it'll take about 21 minutes to fly, and if you take a pic every 5 seconds you'll have 252 shots. Is that enough?

I would do this, using ForeFlight:

1) Create a user waypoint at the peak on your iPad. Call it RANIER.

View attachment 72183

2) Go into Excel. In the first cell, type "1". Fill down to row 360.
3) In cell B1, type ="RANIER/" + A1 + "/5"
4) Fill down to cell B360.
5) With B1-B360 selected, Copy.
6) Go to your email client, paste, and send it to yourself.
7) On the iPad, go to Mail, open the message, select, copy.
8) Go into ForeFlight. You'll need to put at least one waypoint into the flight plan to start.
9) Tap that waypoint, then "Insert After..." and paste.

Actually, now that I played with it a bit, every 10 degrees looks to be plenty.

View attachment 72182

Here you go... Do the first step, then paste this:

RANIER/360/5
RANIER/010/5
RANIER/020/5
RANIER/030/5
RANIER/040/5
RANIER/050/5
RANIER/060/5
RANIER/070/5
RANIER/080/5
RANIER/090/5
RANIER/100/5
RANIER/110/5
RANIER/120/5
RANIER/130/5
RANIER/140/5
RANIER/150/5
RANIER/160/5
RANIER/170/5
RANIER/180/5
RANIER/190/5
RANIER/200/5
RANIER/210/5
RANIER/220/5
RANIER/230/5
RANIER/240/5
RANIER/250/5
RANIER/260/5
RANIER/270/5
RANIER/280/5
RANIER/290/5
RANIER/300/5
RANIER/310/5
RANIER/320/5
RANIER/330/5
RANIER/340/5
RANIER/350/5
RANIER/360/5
Click to expand...

Think it would be easier to just adjust rate to hold 5.00nm from a waypoint vs trying fly a line off a tablet
 
This reminds me of the early 80s and my lessons in a JetRanger. My instructor and I would depart from Hobby, cruise over to the Astrodome and fly circles around it. I would try to keep the shrubs in the outer parking lot ring under my left foot. With Houston's normal 15 or 20 mph south wind blowing it wasn't easy.

I gave up on helicopters after 20 hours. The cost was killing me, and who was going to hire a low time nitwit like me with thousands of VHPA members around?
 
8a0ca1222d9003f77fe52f715a77d162--hobbys-airplane.jpg
 
James331 said:
Think it would be easier to just adjust rate to hold 5.00nm from a waypoint vs trying fly a line off a tablet
Click to expand...

Maybe. And I'd probably set up the panel gear that way... But you're necessarily going to be making adjustments the entire time. Twist 10, turn 10 isn't going to work very well for the OP's purpose unless he's got a gyro-stablized camera mounted on the inside wingtip.
 
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