ACROSS

 1  What chairmen sometimes do together? They tell what time the stars should appear. (10)

 6  Giants’ first base, in trying to rise. (4)

10  Noticed one animal where it might be a job to cut a cord. (7)

11  It’s necessary no longer to have one man, commonly. (7)

12  Gave a false impression about part of the concert? (4)

13  Robin (Hood) or Guy (Lombardo)? (10)

15  Intermit. (7)

16  The cold wind lets the young horses leave and waste away. (7)

17  Gives the horse-laugh to those who scratch? (7)

20  One probably shouldn’t leave the dock in doing so (at least if one is the thinning type). (7)

22  Salome wasn’t the type Hemingway might have hired! (4,6)

23  Irish yarn-spinner? (4)

25  Horatio’s country? If so, there should be a success story. (7)

26  Such a reminder should cause apparent amusement. (7)

27  Plant speed-up? (4)

28  Not really the lead article of the editor–it’s more what he does. (4-6)

DOWN

 1  A flight of rooks? (7,2,3,3)

 2  In case of some difficulty, they should have more than a brief acquaintance. (7)

 3  It’s not quite irrational to expect champagne to be so dry. (4)

 4  Grace should never be so. (7)

 5  Was in apprehension of being both “red” and “dead”? (7)

 7  Went over the limit. (7)

 8  Proving any orange letter might be official! (8-7)

 9  One-time chatty places in high circles. (9)

14  One doesn’t so forget about arms, for example. (9)

18  Makes one attack on the costs of explosives? (7)

19  Water container. (3,4)

20  Is the object to hold with a pin? (7)

21  Like Tennyson’s work, as far as royalty is concerned. (7)

24  Having trouble being reached when there’s no sign of trouble? (4)