7 Nautical signal flag indicating a ship is ready to sail (4,5)
8 Small canoe consisting of a light frame made watertight with animal skins (5)
10 1963 Hitchcock film (3,5)
11 Region of northeastern France famous for its wines (6)
12 The military service concerned with the sea (4)
13 See 1 Down
15 --- Palace, chief residence of the archbishop of Canterbury since 1200 (7)
17 Style of popular music in the 1950s played on guitars and improvised percussion instruments (7)
20 One of the bony segments of the spinal column (8)
22 Queen of the Olympian gods in ancient Greek mythology (4)
25 In Geology, the earliest division of the the Tertiary (6)
26 Breed of large wiry-coated terrier bred in Yorkshire (8)
27 In Greek legend a king of Phrygia to whom Apollo gave ass's ears (5)
28 A light, sweet sparkling red wine of northern Italy (9)

1/13 Second nearest star to the sun also known as Rigil Kent (5,8)
2 Constituent republic of Yugoslavia (6)
3 Drama by Henrik Ibsen with incidental music by Edvard Grieg (4,4)
4 Gianni ---, Italian fashion designer (7)
5 A dissolute character in Shakespeare's plays (8)
6 Venetian gondoliers' song (9)
9 Andalusian city and province on the river Guadalbullón (4)
14 Roman name for Scotland (9)
16 John ---, Poet Laureate from 1972-84 (8)
18 Plant cultivated for its enlarged fleshy turnip-shaped edible stem (8)
19 Madrid's international airport (7)
21 --- gun, rifle used in WW2 - its name is a composite of a Czechoslovakian city and a London borough (4)
23 An intensely radioactive metallic element that occurs in minute amounts in uranium ores (6)
24 Girl who featured in two novels by Lewis Carroll (5)