Airplanes over Deacon's Walk

It's been said that movies try to prepare us subconsciously through subliminal suggestion to accept future events before they occur.  This way, the events will not seem as much of  a shock to us. 

Take 9/11.  Conspiracy theorists claim that some of the perpetrators had Illuminati ties and had foreknowledge of the event.  It was even allegedly referenced in movies, particularly with analog clocks, dates, and other appearances of the digits.  Again, pure speculation. I've no idea if it's true. Below is a screen capture of the episode "The City of New York Versus Homer Simpson" from 1997.

Similarly, people argue that the prevalence of alien invasions/contact made in science fiction movies is trying to subliminally tell us that this type of event will occur some day.  Again, whether this is true, I have no idea, but it certainly is interesting to ponder every once in a while.

That brings me to the title of this post, airplanes over Deacon's Walk.  For those of you who do not know, Deacon's Walk is the name of the neighborhood in which I live.  I have a great house that overlooks the Pike Creek Valley and I can see a long way from my deck.  The sky is open, and it's a great place to relax especially now that it's getting warmer. 

However, for the past six months, something odd has been going on in my neighborhood. Something strange. Something no one talks about. But the question is: do people notice? I think they must, given the in-your-face nature of what happens. People are for the most part home at 8 pm or 9 pm each night. So what gives? (This is what it looks like)

I have a legitimate question about what the hell these things are flying over my house every now and again towards the end of each month.  My brother has seen them.  My neighbors have seen them.  And when I researched them, other people have seen them too.  But no one knows what they are.

They fly low.  They are triangular.  They have four lights on them and if they were exact triangles, they would have one in each vertex, along with one in the middle of the interior. Unless you are standing directly below them, they are silent.  They can rise, however, very quickly.

These planes (I think they might be military, as Dover Air Force Base isn't too far away, nor is New Castle County Airport) fly extremely low and the first few times I saw them I felt like they were going to crash into one of the houses or my own.  I would say that they fly about 500-600 feet off the ground, which from a deck or an upstairs bedroom is slightly scarier. 

The pattern for the past six months is that they fly low and circle the neighborhood (not just the city of Newark, say) three or four times before they vanish.  I've seen them completely disappear on a cloudless night once.  I don't know if it's ever the same plane.  Sometimes the lights look a little different. 

I don't know what they are but it's very creepy.  After the once per month that we see them, they are gone and I forget about them.  But I do know for a fact that in January, February, and last night the same type of thing occurred.  Low flying.  Circling.  Gone.

In fact last night my brother asked if I saw a huge plane on my way home.  Truth is I did, and I slowed down my car to get a better look at it.  It was dark but I saw the distinct triangle and light pattern I'm familiar with from other times. Then I saw it once more after that from inside the house.

What are these things?  Why do they fly so low?  Does anyone know what I'm talking about?  If so, let me know your insights.