Why does Xplane 11 keep crashing on startup due to lack of memory?

Question

Xplane 11 was working up until a few days ago.  I flew one flight, and then later in the day, it wouldn't work.  I can get to the main menu but when I say start a new flight, it loads for a few minutes before giving a memory error.  I haven't changed any settings, so I'm not sure why it all of a sudden doesn't work.  Here is the log.txt:

http://questions.x-plane.com/?qa=blob&qa_blobid=11763077920541145993

Answer 1

X-Plane is totally out of memory. Next time, turn down your rendering settings or remove add-ons to avoid this problem. If you cannot restart X-Plane you may have to delete your preferences, found in the Output folder. You can also remove joystick device. You can read more about Configuring X-Plane to Use Less Virtual Memory here.

Comments

But why is it doing that now? I flew one flight, let it go for a while, and then tried another one with the same rendering settings and it crashed. Why would I have to decrease the rendering settings?