A Q related to air travel.....perhaps pilots can answer....or someone else who knows.

When we travel long distances, I've noticed this:

On the final 1/4 of the flight, the airplane feels like it is speeding up. The engines seem to gun really high. It feels like we are going 1000 mph.

I used to think we were making up time....trying to arrive on time....going extra fast. Now, I think it might be related to the need to dump fuel before we land...so we aren't too heavy to land. So, maybe we're burning off fuel with the jets.

Does anyone know? I feel this on every flight to the VI. What is it that is going on? It lasts about 20 - 30 minutes....and the flight feels really different while it is happening. Nobody around me seems to notice.

I'm determined to find the answer. Thanks to anyone who can help!