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Four Hundred Feet?

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Four Hundred Feet?

Old 01-01-2016, 02:12 PM
  #26  
Lifer
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I'm not uncomfortable about the issue, I just like to do the research first. I'd rather know in advance.
Old 01-01-2016, 02:29 PM
  #27  
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Originally Posted by Lifer View Post
I'm not uncomfortable about the issue, I just like to do the research first. I'd rather know in advance.
Fair enough, that was my word not yours, I should have said concerned. The telemetry thing might be the solution though. Built into the receiver, and the tranmitter barks out battery levels, time in air, and altitude. Logs it too so that it's ever called into question you can always download the proof.
Old 01-01-2016, 03:06 PM
  #28  
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Hey, wait a minute - I got to thinking about those standard, non-modeler, bystander questions - you know the ones: "How fast can it go?" "How high does it fly?" "How far away can you fly?" and thought therein lies the answer: 'Even If I tried to fly my half-scale model up to 400', it would become so small, I wouldn't be able to see it and then it wouldn't matter so therefore I never even get close.' Add to that: 'Anything any smaller can't even come close to approaching half that height without losing sight of it...'

The stress was taking its toll on me - I had several beers when I wrote the reply; I'll review it when I'm more clear-headed.

Last edited by H5606; 01-01-2016 at 03:23 PM.
Old 01-01-2016, 03:22 PM
  #29  
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I am glad I was able to get some flying in today on the first day of the new year the weather here in so cal was great for flying, As for myself I am flying the same as always and as far as I can tell everyone else is also. We are
not going to worry about the 400' limit not that I think that we consistally fly over the limit anyway but I don't have telemetry in any of my models and until its its required I won't worry about it I say just go have fun.
Old 01-01-2016, 03:31 PM
  #30  
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You can easily guesstimate your altitude, by using the surrounding trees. Most of the tall standing oaks, are generally around 80 feet and Spruce trees around 50-60 feet in height. If you've got one, or both growing around where you fly at, then visually picture standing them,(oaks), one on top of the other until you can picture 400ft, or, just use Google Earth and zoom down on where you fly at, until you get to 400 feet altitude, from the ground. I used to do that for about a year and had it down to a science...but I also used the video off my onboard camera to compare it with Google Earths data.
Old 01-01-2016, 04:31 PM
  #31  
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Originally Posted by Maximilionalpha View Post
You can easily guesstimate your altitude, by using the surrounding trees. Most of the tall standing oaks, are generally around 80 feet and Spruce trees around 50-60 feet in height. If you've got one, or both growing around where you fly at, then visually picture standing them,(oaks), one on top of the other until you can picture 400ft, or, just use Google Earth and zoom down on where you fly at, until you get to 400 feet altitude, from the ground. I used to do that for about a year and had it down to a science...but I also used the video off my onboard camera to compare it with Google Earths data.
Comparing the plane's height to trees is a good method, plus time spent at the rifle range will give you a great sense of what similar sized objects look like at measured distances.
Old 01-01-2016, 04:51 PM
  #32  
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Here's one more and it's 99% accurate...Have someone to walk with your plane in hand, across an open field and for every 50 feet, snap a photo of what the plane looks like at that distance, up until they've counted off a couple hundred feet. Once you know what your plane looks like at that distance, then you'll know when it's at, or above that distance, in the air.
Old 01-01-2016, 04:52 PM
  #33  
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Originally Posted by Lifer View Post
Before the thread degrades into a small group of people arguing, I'd still like to find out how the altitude can be determined by the average person or how the authorities can verify my altitude from the ground.
Math. You need an accurate angle measuring device such as a transit and the distance from the object you are sighting. Its a simple calculation to find the altitude of even a distant object. Every FAA GADO likely has access to the equipment and someone qualified to make a legally binding
determination of an aircrafts altitude at any specific point in its flight if necessary.
Anyone who has been in Ag aviation and had low flying complaints knows exactly how this works.
They dont come to your location. They collect evidence from a distance and file it as part of the investigation.

This principle holds true for being too high as well. Calculate angle needed to sight a specific altitude at a known distance and if you are above that line of sight... Snap a picture and put it in the folder.

Is it possible to make a mistake or fudge the results? Absolutely.
You better have recorded data to dispute any claim and defend yourself.

400ft limit is not going to work for glider operations at all. Perhaps the simpler route would be to call Flight Service,get a weather briefing,file a VFR flightplan and open it when Im ready to go up. Close it when Im done. My tag will be up in ATC when its open.

I guess maybe its time for another trip down to the GADO to ask some tough questions Im kind of thinking noone has answers to.
This could end up being fun.

Last edited by Aerocal; 01-01-2016 at 05:22 PM.
Old 01-01-2016, 05:09 PM
  #34  
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Originally Posted by Maximilionalpha View Post
Here's one more and it's 99% accurate...Have someone to walk with your plane in hand, across an open field and for every 50 feet, snap a photo of what the plane looks like at that distance, up until they've counted off a couple hundred feet. Once you know what your plane looks like at that distance, then you'll know when it's at, or above that distance, in the air.
Yes, a .40 to .60 sized RC plane casts a man sized silouette and at 400 feet you can easily see the physical differences between most men and most women.
Old 01-01-2016, 05:30 PM
  #35  
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Originally Posted by Maximilionalpha View Post
Here's one more and it's 99% accurate...Have someone to walk with your plane in hand, across an open field and for every 50 feet, snap a photo of what the plane looks like at that distance, up until they've counted off a couple hundred feet. Once you know what your plane looks like at that distance, then you'll know when it's at, or above that distance, in the air.
You guys are way off base. Scaling by photograph may only be marginally acceptable legally if (and I say if) you are using a professional photographer and the lens length of the equip is certified.
Doesnt sound very practical to me.
Old 01-01-2016, 05:51 PM
  #36  
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Originally Posted by Maximilionalpha View Post
Here's one more and it's 99% accurate...Have someone to walk with your plane in hand, across an open field and for every 50 feet, snap a photo of what the plane looks like at that distance, up until they've counted off a couple hundred feet. Once you know what your plane looks like at that distance, then you'll know when it's at, or above that distance, in the air.
Have someone walk the plane to 400ft and hold it pointing up. Now stretch your arm out and measure the wingspan against the width of your thumb. (or any finger).

In flight you will have a reasonably accurate idea if you are above 400 feet just by holding your thumb up against the plane. Try it against the moon when it looks small in the sky and again when its low and looks larger. (its always the same)
Old 01-01-2016, 05:57 PM
  #37  
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Leading to countless unexplained rc plane crashes as pilots let go of their transmitters and try and cover their plane with their thumb at arms length to see how high they are while flying with only one hand. Where did it go ? I don't know! Do you see it?
Probably not a good idea !

Last edited by flyinwalenda; 01-01-2016 at 05:59 PM.
Old 01-01-2016, 06:00 PM
  #38  
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An accurate distance to the model and angle from horizontal would quickly give an accurate elevation.
Old 01-01-2016, 06:17 PM
  #39  
Rob2160
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Originally Posted by flyinwalenda View Post
Leading to countless unexplained rc plane crashes as pilots let go of their transmitters and try and cover their plane with their thumb at arms length to see how high they are while flying with only one hand. Where did it go ? I don't know! Do you see it?
Probably not a good idea !
LoL, true but no need to cover the plane, holding your thumb along side will achieve the same thing. If a person cant take one hand off the controls for two seconds while their plane is that high in the sky there is something wrong.

Or ask a buddy to do it.

Last edited by Rob2160; 01-01-2016 at 06:58 PM. Reason: initial wording sounded unfriendlier than was intended.
Old 01-01-2016, 06:17 PM
  #40  
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Telemetry based on GPS altitude is probably accurate enough also if you reset to zero before take off.

I recall reading months ago that the 400 feet is above the highest ground elevation within 600 meters (2000ft) horizontally of your aircraft.

Don't quote me on that as it might have been in UK regulations. If I find it again I'll post a link.

That would make perfect sense though as full size aircraft must stay 500 feet above highest terrain within the same distance.

Last edited by Rob2160; 01-01-2016 at 06:54 PM.
Old 01-01-2016, 06:41 PM
  #41  
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if you are curious what size your model would be to your eyes at 400 feet-measure 400 feet from two points on ground, have someone hold your model up in a attitude you normally see if when flying, take a ruler and hold up and start at the nose and read the ruler where the tail stops while standing on one of the points you initially marked off. Take the measurement off of the ruler and make a measure stick with the same length you read on the on ruler and also put two vertical end strips on the measuring stick you made. You can also install a piece of stick on the bottom rail of the measure stick for a handle. Now you can go fly your model and manually check your altitude with this reference device and to know how high you are. I do not have one anymore but it does work -I would post a picture because I do not know if you can follow these instructions but I am building a new bird now and need nothing else on work bench.

Last edited by PLANE JIM; 01-01-2016 at 06:43 PM.
Old 01-01-2016, 06:42 PM
  #42  
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Do an average sized loop. You will be about 400 feet at the top.

I have a Futaba radio with GPS and barometric pressure sensors. Flying my 72" Edge I hit 400 feet during most vertical maneuvers. An average hammerhead will exceed 400 feet if there is any extension to the vertical portion of the maneuver.

My plane averages 60 mph. I have about 3 - 4 seconds of vertical.
Old 01-01-2016, 07:33 PM
  #43  
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Make yourself a simple device, such as this one that I drew up in paint. Mark it off at whatever intervals you choose necessary for whatever sized craft you're intending to fly, using the earlier method that I've given you about walking across an open field. The triangular-shaped object on the stick, slides back and forth and works to sight the object. I think you get the idea.
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Old 01-01-2016, 08:02 PM
  #44  
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https://youtu.be/8O5DAZ-pcDk Here's an excellent chance to show off one of my little planes...
Actually....I have been having problems the past few years with "Full Scale" planes flying low across my field. This site is 1/2 mile from Interstate 5 and borders with a very busy commercially zoned boulevard, shopping centers, etc.
I had the local airport managers take a look at this video so that they could tell me how high they figured the plane was that flew right through the center of the loop that my 18 INCH SPAN model did.
I'm talking about the close encounter at the 30 second mark.
Both of the airport managers estimated that the full scale plane was at 500 feet if not higher.
I made it clear to them that my plane only has 18 inches of span and they "stuck to their guns", plus they warned me that I should be flying lower....!!
LOL.
Old 01-01-2016, 08:05 PM
  #45  
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Most full grown oak trees are around 80 to 120 ft; so guess? Thus if your plane is five time the height of a mature Oak you are probably over the limit: Dive.

However, I believe these new rules are illegal under HR658, unless you are flying beyond your line of sight.
Old 01-01-2016, 08:48 PM
  #46  
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Originally Posted by combatpigg View Post
https://youtu.be/8O5DAZ-pcDk Here's an excellent chance to show off one of my little planes...
Actually....I have been having problems the past few years with "Full Scale" planes flying low across my field. This site is 1/2 mile from Interstate 5 and borders with a very busy commercially zoned boulevard, shopping centers, etc.
I had the local airport managers take a look at this video so that they could tell me how high they figured the plane was that flew right through the center of the loop that my 18 INCH SPAN model did.
I'm talking about the close encounter at the 30 second mark.
Both of the airport managers estimated that the full scale plane was at 500 feet if not higher.
I made it clear to them that my plane only has 18 inches of span and they "stuck to their guns", plus they warned me that I should be flying lower....!!
LOL.
You were definitely not flying above 400 feet here and the full size was much higher than you. Take the size your of your 18 inch wingspan at 30 seconds and compare it to the size of the tail on the full size at 32 seconds. The tail on the full size is much larger than 18 inches yet looks tiny compared to your wingspan. The apparent speed across the sky is another clue - the full size would by flying faster even though the apparent speed in the video is slower.

If both were at the same height the apparent sizes would look very different.

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Old 01-01-2016, 08:57 PM
  #47  
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I'll take your word for it.
It looked to me he was at much less than 500 feet, based on what I think his plane would look like if it was parked at the opposite end of a football field, plus an additional 200 feet.
Old 01-01-2016, 09:20 PM
  #48  
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Originally Posted by Lifer View Post
Thanks for the reply, but my question is how someone else can determine that I have flown higher than 400 feet.
Why would they be doing that?? There is no such rule either now or proposed.
Old 01-01-2016, 09:23 PM
  #49  
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Just from slowing down the video and viewing it, I can most assuredly tell you, that the private plane, is, below 500ft, but just barely. He's also more diagonal to you then he is vertically above you. Question is, what's the tallest structure close by your property, because he's supposed to be 500ft above the tallest ground structure....unless, (and there are exceptions to this rule), he's coming in for a landing, or taking off from the airport. From the looks of how the plane was flying, he was going in for a landing.
Old 01-01-2016, 09:27 PM
  #50  
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Originally Posted by combatpigg View Post
I'll take your word for it.
It looked to me he was at much less than 500 feet, based on what I think his plane would look like if it was parked at the opposite end of a football field, plus an additional 200 feet.
Here is another perspective of 18 inches against a Cessna 152.

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