Across:
1 Short? Not in factory ship (‘short’ not in ‘factory ship’ = facyip = PACIFY) – relax! (PACIFY),
4 One of those forgettable types (AMNESIAC) of academicians dropping acid (‘academicians’ dropping ‘acid’ = aemcians = AMNESIAC),
9 Custodian (CAPTOR) of Cork (cork = CAP-) hill (-TOR) (CAPTOR),
10 Most of (y) the analysis (‘study’ without ‘y’ = STUD-) on promissory notes (IOUs = -IOUS) (STUDIOUS) is academic (STUDIOUS),
12 Very similar (LOOKALIKE) search for (LOOK-) something positive on Facebook (‘a like’ = -ALIKE) (LOOKALIKE),
13 Marshal (ALIGN) from Orient? (ALIGN),
14 Keep things cool (AIR-CONDITION) in state (-CONDITION) after (= positional indicator) broadcast (AIR-) (AIR-CONDITION),
18 Partition (SCREEN-) is the work of the judge (WRIT-) and British monarch (Queen Elizabeth / Elizabeth Regina = -ER) (SCREENWRITER) – one needs to put words to that for a film (SCREENWRITER),
21 Leaves follower behind (LOSES follower) with running (= anagram indicator) soles (soles = LOSES),
22 University (-U-) in Art Deco (art deco = ED-CATOR-) building (= anagram indicator) with society (-S) (EDUCATORS) of professors (EDUCATORS),
24 Knock off Number One, for instance (DISLODGE), with short (c) record (‘disc’ without ‘c’ = (DISLODGE -) by group (group/branch = -LODGE) (DISLODGE),
25 Swinger’s warning (warning on golf course = ‘fore’ = F-ORE) about old city (-UR-) (FURORE) commotion (FURORE),
26 Part payments (DEPOSITS) for butcher’s (= anagram indicator) topsides (topsides = DEPOSITS),
27 Clear out (BEAT IT) with a Tibet (a Tibet = BEAT IT) model (= anagram indicator).
Down:
1 Freakish (PECUIAR) exercise (PE-) to take out (cut) short (t) (‘cut’ without ‘t’ = -CU-) fiction writer (-LIAR) (PECULIAR),
2 Prize (CUP-) for playing chess (-BOARD) (CUPBOARD) in The Press (CUPBOARD),
3 Freeloaders see red vacating (‘freeloaders’ ‘see red’ vacating / without ‘see red’ = floar = FLORA) what’s essentially the country life (FLORA),
5 Heard from the beginning (MOTHER TONGUE), the babes out there understand that lingo! (MOTHER TONGUE),
6 Do one’s best (ENDEAVOUR) around Eve (around Eve = ENDEAVOUR) Cook? (= anagram indicator),
7 Representative (ICONIC) centres of Official Unionist cynicism (centres of ‘ Official Unionist cynicism’ = ic+on+ic = ICONIC),
8 Aim to get out of magician’s (‘aim’ to get out of ‘magicians’ = gcians = CASING) shell (CASING),
11 Short section in song (middle eight = MIDDLE-EIGHT) about women (-W-) (MIDDLEWEIGHT) in The Ring (MIDDLEWEIGHT is in the ring),
15 Opportunities (OCCASIONS) for officer (officer commanding = OC-) playing (= anagram indicator) casinos (casinos = -CASIONS) (OCCASIONS),
16 A pint of plain (stout = ST- OUT) contains sustenance (food) that needs no introduction (f) (‘food’ without ‘f’ = -OOD) (STOOD OUT) – it’s as plain as the nose on one’s face (STOOD OUT),
17 Pops cert (pops cert = PROSPECT) out (= anagram indicator) in anticipation (PROSPECT),
19 Went smoothly (GLIDED) for director general (DG = G-D) setting up (= reversal indicator) over new (= anagram indicator) deli (Deli = -LIDE-) (GLIDED),
20 Finishes the lot (USES UP) and takes drugs (USES) to stay awake (UP) (USES UP),
23 Keen (ACUTE) for a (A-) cut (-CUT-) at flyweight at the centre (‘flyweight’ at the centre = -E) (ACUTE).