ms. mac asked me a question on the way to the airport yesterday morning:
"What causes a sonic boom?" and she also posed the supplementary question: "Can a pilot hear the sonic boom that his aircraft creates?"
I'll answer the first question first (which seems logical):
When an aircraft travels through air, it leaves a wake behind it just like a speedboat does as it travels across a lake. Of course, the wake is a three-dimensional cone rather that a two-dimensional vee.
Now, remember the last time you were at the lake and those arseholes were cruising up and down the lake whilst you were trying to relax in the middle? Do you remember the sound as the waves from the boat's wake crashed onto the shore? As the plane flies along, it drags the cone of pressure waves along behind it like a skirt. As the waves of air crash into the surface of the land below and behind the aircraft, we hear a sound like an explosion. The sound of the turbulent waves of air "smash" into the ground is the sonic boom.
In answer to the second question, the pilot doesn't hear the sound because he is travelling faster than the sound waves so they cannot reach him.
In other news:
The Grumpi was an exceedingly long day and all of us left here at chateau mac are exhausted. The Feuerball team from Ewan's class didn't have the best of finshes and football was clearly the winner in that case. The Patrick Stars posted an exceptional 5th (out of 5) so again football was the winner.
However, the Crazy Cows team were absolutley storming and managed to come a very creditable 3rd. Yours truly blasted home a pair of exceptional goals that ms. mac failed to see, owing to her Paris based absence.
I am nbow paralysed and will be forced to drag myself around the house on a skateboard a la Eddie Murphy in Trading Places till the muscles repair and the broken bones knit.
God I feel old!!!