| CHUCKYEAGER | The first pilot confirmed to have exceeded the speed of sound in level flight |
| YEAGER | Chuck -; test pilot who was the first to have exceeded the speed of sound in level flight (6) |
| TRURO | City of ---, celebrated as the first British steam locomotive to have exceeded 100mph (5) |
| ODED | Exceeded the speed limit? |
| SWIFT | Hunting, eating, sleeping, mating and drinking raindrops on the wing, the fastest bird recorded in level flight (5) |
| IMMELMANNTURN | Aerobatic manoeuvre resulting in level flight at higher altitude in the opposite direction |
| GLENNIS | Glamorous ____, nickname of Chuck Yeager's plane which broke the speed of sound in 1947 (7) |
| SONICBOOM | Sound produced by an object travelling faster than the speed of sound; in dry air, approximately 760 mph (5,4) |
| SONIC | (of speed) Having or caused by speed approximately equal to that of sound in air at sea level. |
| MACHINIST | Factory worker achieving speed of sound in back street (9) |
| ELF | We've never seen one in level flight |
| KRONFELD | Robert ?, Austria-born sailplane designer; first pilot to fly a glider across the English Channel |
| BLERIOT | Louis -, first pilot to fly over the English Channel (7) |
| STEREOPHONY | One hopes try may be the outcome of sound-in-the-round (11) |
| WILEY | __ Post, first pilot to fly solo around the world |
| CHEVALIER | No end of sound in shout of encouragement for old knight |
| SILENCE | Lack of sound in scene devised around the Italian (7) |
| ISLANDER | Man's son maybe confirmed to be big hit (8) |
| ATOAOFBEANS | In level terms, what "the problems of three little people" don't do "in this crazy world"? |
| AMBIENTNOISE | General level of sound in an area (7,5) |
