Cryptic crossword No 1,347

Across

1. T-38 seconds to launch! (4)
2. Working out at first gym class (9)
3. Premium Etsy shop over-stocks this set of things (6)
4. Zero odds of bad guy daring to show tenacity (8)
5. Canniest manoeuvres, for example (8)
6. Tenor enters, nailing stagecraft (6)
7. Tract of million-acre Hebridean island (4)
8. Firm installs genuine-article security device (4,5)
9. Staggering early GCSE results in black and white (9)
10. Parties hard, displaying wealth (4)
11. Discovered hangar storing Golden Fleece? (6)
12. Runner and personal trainer have run away (4,4)
13. Say Apollo 13 worked round likely mishap after evacuation (8)
14. Mix up clothing at laundrette when exhausted (6)
15. Hardened criminal clutches diamonds, clearly guilty (3-6)
16. Reddish-brown insect caught as newborn (4)

Down

1. Check out fit Yankee in sci-fi flick (3,2)
2. Soothe with teas brewed repeatedly (3,2,4)
3. Trailblazer detective born to crack officer's case (7)
4. Dawning eureka involved disillusionment (4,9)
5. Drat, a rotter's won card game (5)
6. Police station has corrupt means to obtain addresses (9)
7. Fellow knight ignoring plague symptom (13)
8. Part of cell block at hub generally unfinished, dilapidated (9)
9. Gold song-books I'd put back in theatres (9)
10. A bishop mostly sent to cover Church of England's lack (7)
11. 23 hitpoints, low but rising (5)
12. Springy boot? (5)