My childhood visions (part 1)

When I was a kid, I used to see things that can't be explained. There was a number of these strange visions so I've considered writing about them and break them into parts for this blog.
When I was about four or five years old, I was in the back garden one sunny morning. It was soon after breakfast. My nan was putting washing up on the clothes line. Then I saw a strange vision appear above the rooftops of the houses in the neighbourhood. It looked like a massive silouette of a giant "bird". It didn't move, it was stationary and seemed to be like a red outline or shadow of a giant winged animal. It seemed bigger than our house.
I remember feeling excited. I pointed up at it and cried "Look! What's that? Look! Look!"
My nan didn't see it and she didn't know what I was talking about because I had to keep pointing and telling her to look up there. She continued pegging clothes on the washing line as normal.
The giant winged creature faded away and was gone.
The massive giant "bird" resembled a prehistoric creature instead of any large species alive today. About its shape, the thing seemed eerily similar to a pterosaur, that was very huge as the enormous winged hatzegopteryx and quetzacoatlus that lived in the dinosaur era.
What was it? My guess here is that as a child, I was able to glimpse something that was probably there in that exact place at that time of day, many millions of years ago.