Sunday Business Post Crossword

[annportach]

I've only just registered, so I'm still finding my feet. So, I've three clues I can't figure out -
21a The alternative part of a heavenly path (5) O ? ? ? T
2d Write the complete letter for a friend (4) A ? L ?
12d A sailor in vile surroundings is capable of surviving (6) ? i ? ? ? e
Thanks

[ladyalex]

12d Viable

[sarumite]

21a Or bit
2d All y

Welcome to ABank ann

[ladyalex]

21a Orbit

2d looks like Ally, but I cannot figure out why ALL + Y but don't get the Y bit

[ladyalex]

Hello sarumite. Well, I hope ?

[sarumite]

hi ladyalex .. All (complete) + y (letter) ;O)

All's well thanks ... and you?

[ladyalex]

Thanks for the explanation, Sarumite.
I'm fine, but very very grumpy as I should be in the US but my flight got cancelled because of the ash. Going next Monday, though, ash permitting.
:-((

(Apologies, annportach)