No 12626, Wednesday 15 May 2019, Spinner

ACROSS
1   Discovery, perhaps, of part of Atlantic Ocean (7,7) ENGLISH CHANNEL [DD]
10 Film's length doubled, characterization's length halved (5) E?G?T {Addendum - EIGHT Definition by example - FILM has 4 letters so 4x2 = 8, Ch.....oN has 16 letters so 16/2 = 8- See comments) 
11 Trusting person turning evil inside (9) BELIEVING {BE{VILE*}ING}
12 Warrior's key weapon in space (8) SPEARMAN {SP{E}{ARM}AN}
13 Show watched on earning credit (6) SCREEN {S{CR}EEN}
15 Committed to keep Spinner's crossword at the end (10) DETERMINED {DETER}{MINE}{c...rD}
16 Operates open top vehicles (4) USES bUSES
19 Key tribute by leader of congregation (4) CODE {Co...n}{ODE}
20 House with no roof holds one policewoman's aircraft (10) HELICOPTER {sHEL{1}{COP}TER}
23 Listener absorbs bit of speech that is less complicated (6) EASIER {EA{Sp...h}{IE}R}
25 Average celebrity captured with daughter (8) STANDARD {ST{AND}AR}{D}
27 Century featuring strokes from centre to boundary with a hint of Tendulkar's style (9) TRADITION {T{RADI{Te...r}I}ON}
28 A fairy tale's very moving (5) ALIVE {A}{LI{V}E}
29 Suspension on being found tainted might necessitate such an act of tidying-up (6-8) SPRING-CLEANING {SPRING}{CLEANING}

DOWN
2   Forgotten politician, finally put in power, getting good (9) NEGLECTED {p...aN}{E{G}LECTED}
3   Written programme missing in trails left (8) LITERARY {L}{ITinERARY}
4   Takes to court over box having half-spoilt sandwiches (10) SUBMARINES {SU{B{MARred}IN}ES}

5   Cry endlessly before man brings self-control (4) CALM {CALl}{M}
6   Hundred years after era restraining new business (6) AGENCY {AGE}{N}{C}{Y}
7   Racket of number one seed broken in half (5) NOISE {NO}{1}{SEed}
8   Saga's climax kept under wraps by members (7) LEGENDS {LEG{END}S}
9   Ragged clothing protects like denim, basically (6) TEASED {TE{AS}E}{De..m}
14 Defiance increases in revolt with time (10) RESISTANCE {INCREASES}* over {T}
17 A suit running on charge keeps Tony's head in place (9) SITUATION {A+SUIT}*{Tony}{ION}
18 Chief gets dismissed on gaining some negative prominence (8) MOUNTAIN {M{OU{Ne...e}T}AIN}
19 Manufactures drug in boxes (7) CREATES {CR{E}ATES}
21 Director's more disrespectful after winning award ultimately (6) RUDDER {RUD{a..rD}ER}
22 Walk out as player breaks rule (6) RESIGN {RE{S}IGN}
24 Part of flight's sensors trashed initially by wind (5) STAIR {Se...r}{Tr...d}{AIR}
26 Essentially seizing corporation making metal (4) ZINC {seiZing}{INC}

Reference List
Key = E = Drug, Century = TON, Very = V, Good = G, Left = L, Man = M, Hundred = C, Years = Y, New = N, Clothing = TEE(shirt), Charge = ION, Player = S(South in Bridge), Corporation = INC

GRID