Sunday Telegraph Cryptic 2626

[tabbycat09]

Help needed please
13 down
Practice needed for balancing acts 11 letters A?C???T?N?Y
Also 19 across Fall or almost fall, second from front 6 letters ?????E

20 down Book that is including design for aircraft 7 letters
??P?A?E

thanks in anticipation

[factor-fiction]

accountancy

[JoolsTwo]

20d Biplane

[bibblebub]

19a) (s)TUMBLE