FlightAware Discussions

Curious stats changes

I’ve noticed over the last few weeks that I appeared to have had a slightly lower message rate being received than I was seeing previously. I attributed this to the changes in traffic going from summer towards winter, but now I’m not so sure.

Here’s a graph showing the past week, overlaid on the preceding month:

Some weeks ago in @keithma’s thread about raising his antenna several people noticed a sudden brief dip in their stats, and there was quite a lot of speculation about what might have caused it because of the bad weather that day.
I noticed something similar yesterday:

I look at Keith’s graphs and he also has the same dip yesterday across all three of his receivers, which means it is a real effect, not just local to me.

What I’ve also noticed is that the message rate (and message rate per aircraft) has been consistently higher since that point:

Perhaps there was some change to interrogations being made by air traffic control that has resulted in the increased message rate. It’s the second time this has happened coinciding with bad weather, but i don’t think it’s being directly caused by a weather effect as I’ve seen similar conditions at other times with no interruptions like this.

I was wondering if other people near the SE UK have noticed similar.

Nothing seen here - South Oxfordshire.

I saw another such dip just after I posted this:

I have dips at the same time as you both yesterday and today.

It’s the lunch break :smile:

I have such drops almost every day beginning at 7pm local time. But the traffic comes back until approx 10pm

My TV does this to a setup in my bedroom. The antenna is about a metre from the Antenna.
Could it be some sort of interference?

Maybe, but it would have to be something not particularly localised - eg keithma’s receiver’s are ~35nm away from mine and I see the same effect in his graphs.

That doesn’t seem likely.

And I am ~65nm away.

Our airport at the end of October switches to a winter schedule. Traffic is reduced twice. The number of transit flights that my receiver watches is also gradually decreasing by January.

Curious, very curious.

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I’m in France near Paris and i have the same in my graph, and at this moment the weather was good !

This is not the first time I see this phenomenon, the first time I thought it was due to heavy rains, but since then it started again when the weather was cavok.
And every time I found this on the graphs of other people like keithma for example.

Depending on your range the weather is normally only a local problem with impact to only a few number of aircraft around you.

I had an unusual drop this morning as well in my message rate without changing anything before.

Curious question, do you have any clocks you changed today?

Joking aside, the change from daylight savings time changes schedules.
Also your graphs aren’t relative to UTC but rather the local time that was changed.
So your yellow band and green line will be wonky for a week.

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The only clock i needed to adjust manually is at the oven in the kitchen, my wife hates smart devices :rofl:

But a good question, i expected the Raspi to change the time as well (which it did)
You’re right, the traffic pattern for the flyover did not change, it’s myclock which changed. This came together with the local traffic in germany, so the graphs must be different to yesterday (or any other sunday) before.

Here we have the duplicate hour due to the daylight saving switch.

It counts 00:00, 02:00, 05:00 but the distance of both timeframes is the same

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