Another line of sight discussion

[Greetlander]

Apologies but I had a nerd out moment earlier, and as I enjoyed the other line of sight thread figured this may have some traction.

I live in the Northern suburbs of Sydney and driving home today was taken with a plane high above executing a turn. I stopped on the road and photographed it with my phone just at the point where the plane itself was no longer visible to the naked eye, but the contrail was clear.

Using an app I've ascertained that the plane was 89 miles away in a straight line, but 154 miles to drive. I'm fairly sure the end of the trail would have been visible for another 5 minutes if I'd stayed so you could give it 100 miles visibility.

Thing is we have mountain ranges (big hills really) in the way. This is a bit like seeing a plane over Blackpool from Leeds. I wonder if people who live on the edge of the country can see further away than that? Is a plane over Normandy visible from S. England or SW Wales?

 

[Kingspanner]

https://www.cactus2000.de/uk/unit/masshor.shtml

The above links to a line-of-sight calculator that allows arbitrary elevation for observer and target than works out how far apart they can be before the horizon is in the way. All based on geometry of course, not taking in local conditions. Set the altitude for a plane to say 10,000 metres and away you go. (With a really long focal length lens!)

 

[Peter Mugridge]

Is a plane over Normandy visible from S. England or SW Wales?

Yes, but it does need one of those very rare completely crystal clear days - it's unfortunately very hazy most of the time, even on a sunny day. You also need a good, clear, sightline to a neutral horizon.

I have followed aircraft via their contrails, verified via live tracking websites, some considerable distance from overhead in or near Epsom and I can say for certain that it is possible to see them when they are over places like the Channel Islands, South Wales, Birmingham... So while it's not possible to see the aircraft itself at such distances, I'd say the front of the contrail counts for the purposes of this discussion.

 

[route101]

From Glasgow looking Southwest i can see them over Northern Ireland.

 

[nlogax]

From Glasgow looking Southwest i can see them over Northern Ireland.

From which point in Glasgow? Am there a lot, wouldn't mind catching this view myself.

 

[route101]

Either from the Campsies facing or high point in City Centre facing South , the New college is great for that . Or Hills south of Glasgow .

 

[Greetlander]

https://www.cactus2000.de/uk/unit/masshor.shtml

The above links to a line-of-sight calculator that allows arbitrary elevation for observer and target than works out how far apart they can be before the horizon is in the way. All based on geometry of course, not taking in local conditions. Set the altitude for a plane to say 10,000 metres and away you go. (With a really long focal length lens!)

Many thanks for this