dipul - Unmanned Aviation digital platform
What information does it provide? | For whom? | What tools are provided? |
---|---|---|
Category of drone operations Safety recommendations How to register as an operator Legal basis Geographical zones | Federal and National aviation authorities Map tools for geographical zones (+WMS) s |
- Identify locations A and B on www.dipul.de (use the address field)
- Measure the distance between A and B using the external tool www.geoportal.de/map.html
- 1.9 km
- How many different coloured geo-zones are there between A and B? 6 zones or 41 zones
- Calculate the distance between A and B (orthodrome = 6371 km) - This is the middle Earth radius
Definition
An orthodrome or a great circle is the intersection formed by a sphere and a plane. The arc of an orthodrome is the shortest distance travelled on a sphere between two points
Answer Both locations A and B are in Flatowallee 28 and Harbigstraße 34 respectively, both of them being falling under restricted geographical zones. The distance measured between A and B in geoportal.de is roughly 1.9 km. There happen to be 41 geographical zones between both the locations when drawing a circle The calculated distance is 9 km
My procedure
- The identification of locations is already done for me, the coordinates are given to me anyways - Flatowallee 28 (52° 30′ 43″ N 13° 14′ 27″ E) and Harbigstraße 34 (52° 30′ 01″ N 13° 15′ 38″ E)
- I went to geoportal.de/map.html and measured the distance. I had to go to Tools and select the “Measure distance” tool, which helps me draw a line between the two points whose distance I want to measure. It was a bit wonky as I couldn’t easily place two points on the map so I had to switch points while the line was being drawn but I got the distance between A and B as 1.9 km
- I went back to dipul and drew a circle between A and B and I counted the total number of geographic zones that showed up. Earlier, I got 41 zones but upon repeating the process, I’m getting 32 zones? Odd, am I making a mistake somewhere?
- To calculate the great circle distance/arc length/orthodromic distance, I had to refer to Wikipedia for the formula and here it is , — Latitude Longitude coordinate pairs of A(1) and B(2) in degrees — Absolute difference of latitudes (degrees) — Absolute difference of longitudes (degrees) — Central angle (degrees) — Mean Earth radius (km) — Arc length/great circle distance/orthodromic distance (km)
Using the formulae, I arrived at = 9 km I find it strange that the arc length isn’t matching with the distance I measured before (1.9 km). Is there a conceptual misunderstanding?
The answer
So, on geoportal.de, one of the points was already marked. How was that possible? I suppose there’s either some tool I missed or they had imported the data from Dipul’s map tool over directly. Either way, the correct answer is 1.861 km. Quite close to mine!
I was extremely wrong with the geographical zone count. The actual number of zones between A and B is just 2 Christoph found just 2. This doesn’t match with what I found on the web map tool. Anyways, here, he identifies that there are only two differently coloured categories between A and B. I will have to retry this myself So the difference is that he didn’t account for temporary operating restrictions (red-tinted shades on my map tool) while I took them into consideration. Also, he didn’t count the exact number of zones. Instead, he counted the number of different colours. Essentially, he was asking for the number of types of geo-zones between A and B and not the actual count itself. Hence the discrepancy
As for the orthodrome distance calculation, I applied the correct formula but the reason my answer didn’t match the measured distance is silly — I switched the latitudes and longitudes in my calculation! Notations are confusing :(