Independent on Sunday 1800 Umpire

Thank you to Umpire. Definitions are underlined in the clues.

Across
1. Bit of equipment from school gym caught in zip (6)
PENCIL : PE(abbrev. for “physical education”, or “gym” in a school curriculum) + [ C(abbrev. for “caught” in cricket scores) contained in(in) NIL(nothing/zip in North American slang) ].

5. Pig primarily investigates with nose, uprooting new problems (7)
PUZZLES : 1st letter of(… primarily) “Pig” + “nuzzles”(investigates something by pushing against it with the nose and mouth) minus(uprooting) “n”(abbrev. for “new”) .
Answer:  …, 3 of which may be found in the grid.  You’ll have to use a 1 across to solve these:

  

9. Headcase having row on the phone? (5)
SKULL : Homophone of(… on the phone) “scull”(to row in a boat with only one rower and a pair of oars).
Defn: …, or, the casing of one’s head.

10. Race madly to produce competition’s first cracking dessert (5,4)
CREAM CAKE : Anagram of(… madly) RACE + MAKE(to produce/manufacture) containing(… cracking) 1st letter of(…’s first) “competition”.

11. Difficult to hold large live weapon (7)
HALBERD : HARD(difficult) containing(to hold) [ L(abbrev. for “large”) + BE(to live/exist) ].

12. Hand in dictionary that’s left out (7)
OMITTED : MITT(a person’s hand) contained in(in) OED(abbrev. for the Oxford English Dictionary).

13. Bolt seat, securing last pieces of track bike build (9)
SKEDADDLE : SADDLE(seat on the back of a horse, or a bicycle or motorcycle) containing(securing) last letters, respectively, of(last pieces of) “track bike build”.
Defn: …/depart quickly.

15. Small joke given a whirl? (4)
SPUN : S(abbrev. for “small”) PUN(a joke, specifically, a play on words).

18. State that USA incorporates after revolution (4)
UTAH : Hidden in(… incorporates) reversal of(… after revolution) “that USA”.
Defn: … in the USA.

20. Initially surveying lake, heard not a dicky bird (9)
SHELDRAKE : 1st letter of(Initially) “surveying” + anagram of(… dicky) [ LAKE+ “heard” minus(not) “a” ].

23. English artist certain for cancellation (7)
ERASURE : E(abbrev. for “English”) + RA(member of the Royal Academy of Arts, an artist) + SURE(certain/doubtless).

25. After money’s spent in hobby, succeeded making baked goods (7)
PASTIES : “m”(abbrev. for “money”) deleted from(After …’s spent in) “pastime”(a hobby) + S(abbrev. for “succeeded”).

26. Message imparted by animated movie about cocaine trouble (9)
VOICEMAIL : Anagram of(animated) MOVIE containing(about) C(abbrev. for “cocaine”) + AIL(to trouble/to worry).

27. One working to stop tracks like heavy metal? (5)
IRONY : I(Roman numeral for ”one”) + [ ON(working/functioning) contained in(to stop) RY(abbrev. for “railway”/train tracks) ].

28. See you in port on Red Sea, nude (7)
CHEERIO : RIO(short for Rio de Janeiro, Brazilian port) placed after(on) [ CHE(Guevara, a Marxist/red) + “Sea” minus its 1st and last letters(nude) ].

29. Very small letter and flower personal assistant dismissed (6)
TEENSY : TEE(the letter “T”) plus(and) “pansy”(a brightly coloured garden flower) minus(… dismissed) “pa”(abbrev. for “personal assistant”).

Down
2. Enthusiastic when sex aid turns up right on time (9)
EBULLIENT : Reversal of(… turns up, in a down clue) LUBE(short for “lubricant”, an aid used during sexual intercourse) + LIEN(a legal right to keep possession of someone’s property until debt is paid) + T(abbrev. for “time”).

3. Bulk of cream lad mixed to make hot dip? (7)
CALDERA : Anagram of(… mixed) [ all but last letter of(Bulk of) “cream” + LAD ].
Defn: A hollow/dip in a volcano made after it erupts and collapses.

4. Bright student at university beginning to correct papers (5)
LUCID : L(letter displayed by a student driver) plus(at) U(abbrev. for ”university”) + 1st letter of(beginning to) “correct” + ID(identification papers/documents).

5. One Piece serial ultimately broadcast for a long time (9)
PLEIOCENE : Anagram of(… broadcast) [ ONE PIECE + last letter of(… ultimately) “serial” ].
Defn: A specific epoch/a long period of time in the geologic time scale.

6. Up-and-coming tech company in southeast Australia hacked computers? (7)
ZOMBIES : Reversal of(Up-and-coming, in a down clue) { IBM(abbrev. for the International Business Machines Corporation, a technology company) contained in(in) [ SE(abbrev. for “southeast”) + OZ(nickname for Australia) ]}.
Defn: … giving another person control over them without the owners’ knowledge.

7. Inclined to wash, disregarding cold temperature (5)
LEANT : “clean”(to wash/launder) minus(disregarding) “c”(abbrev. for “cold”) + T(abbrev. for “temperature”).

8. Gutted sergeant prepared to be stripped of hat and uniform (6)
STEADY : Internal letters deleted from(Gutted) “sergeant” + “ready”(prepared/set to go) minus its 1st letter(to be stripped of hat/top, in a down clue).
Defn: …/unchanging.

9. Separation of Greek characters participating in kinky sex (6)
SCHISM : CHIS(plural of Greek characters, chi) contained in(participating in) S-M(abbrev. for “sadomasochism”/kinky sex).
Defn: …/split between opposed sections in an organised group or society.

14. Somebody wanted translation of Prose Edda (9)
DESPERADO : Anagram of(translation of) PROSE EDDA.
Defn: … by the law.

16. You heard old lady picked up Finnish without opposition? (9)
UNANIMOUS : Homophone of(… heard) “You” + NAN(a child’s word for a grandmother, an old lady) + reversal of(picked up, in a down clue) SUOMI(the Finnish language).

17. Male, fending off onset of infection, comfortably piddling (6)
MEASLY : M(abbrev. for “male”) + “easily”(comfortably) minus(fending off) 1st letter of(onset of) “infection”.
Defn: …/ridiculously small or trivial.

19. Europe supports snubbed drag act at last for Pride (7)
HAUTEUR : [ EUR(abbrev. for “Europe”) placed below(supports, in a down clue) “haul”(to drag/pull along) minus its last letter(snubbed …) ] + last letter of(… at last) “act”.
Defn: …/haughtiness.

21. Disapprove of president after empty deal is accepted (7)
DISLIKE : IKE(nickname of former US president, Dwight Eisenhower) placed below(after, in a down clue) [ Internal letters deleted from(empty) “deal” containing(… accepted) IS ].

22. Policeman arrests vile criminal in hip area (6)
PELVIC : PC(abbrev. for “police constable”/a policeman) containing(arrests) anagram of(… criminal) VILE.

24. Something cheeky Independent welcomed in surface (5)
ARISE : ARSE(slang for one’s buttocks/something made up of 2 cheeks) containing(… welcomed) I(abbrev. for “Independent”, a member of the Independent Party).
Defn: To emerge/become apparent.

25. Trial drug, snorting one line (5)
PILOT : POT(informal term for the drug, cannabis) containing(snorting) [ I(Roman numeral for “one”) + L(abbrev. for “line”) ].
Defn: …/something done as a test before being introduced widely.