Cryptic crossword

[kawagino]

Struggling with this crossword:
21a content to stay very quiet amid mown grass ?????(5)
27a elected second chamber ???r?e?s (8)
2d shopping aid? Revolution happening! C???o?(6)
3d religious dissidents make declaration in confusing soap ?????a?? (8)
16d vehicle swiftly gains cover ?i???a??(8)

Very grateful for any help

[bert_h]

21a very quiet = PP (from music), mown grass = HAY, so content = HA-PP-Y

[bert_h]

3d APOSTATE

[MarkRae]

27a CONGRESS - not particularly cryptic...

[MarkRae]

2d CART-ON

[elliemay1]

Anyone got 16d yet?

[boxtops]

something FAST?

[kawagino]

16d is now ?i?a?a??(8)

[elliemay1]

AIRCRAFT fits and it's fast but...?

[elliemay1]

It doesn't fit now!

[kawagino]

16d i is from obtains containers - tins
A is from happy (thank you bert)
And a is from parish - capital letter for religious district

Thank you for helping

[boxtops]

could Obtains containers-= cans?

[MarkRae]

Which crossword is it, BTW?

[Oldred]

carapace ?

[Oldred]

16d bags ?

[shoota]

Carapace

[boxtops]

nice one oldred - car-apace - I like it.

[Lie-in King]

2d Coup-on (?)

[elliemay1]

I think carapace is correct as it's a shell or cover of certain creatures.

[kawagino]

This crossword is in a dental magazine. Sorry to mislead you with tins on 16 d.

[kawagino]

Thank you for your help. Very grateful