"planes fly by moving air up" simply fails the sniff test - every action has an equal and opposite reaction, after all, so anything that throws air up must be pushing itself down. Since lift is a net upward force on a wing exerted by air, there has to be a net downward force on the air.
Then, to your PS, If a huge amount of energy is required to break the speed of sound, you've explained why commercial jets don't exceed mach one, not why they don't get within 100mph of it.
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"planes fly by moving air up" simply fails the sniff test - every action has an equal and opposite reaction, after all, so anything that throws air up must be pushing itself down. Since lift is a net upward force on a wing exerted by air, there has to be a net downward force on the air.
Then, to your PS, If a huge amount of energy is required to break the speed of sound, you've explained why commercial jets don't exceed mach one, not why they don't get within 100mph of it.