I tried posting this earlier, but it went into the ether or I hit the wrong button.

I learned (more than once) in SAR the three basic rules of carrying survival gear.

1 Keep your pack with you.

2 Keep your pack with you.

3 Keep your pack with you.

Some things have to be on your body however, since avalanche etc may take your pack without approval.

Beacon ( so your Bud's can dig you out)
Radio/Cell
Knife
Fire-making
Trash bag for shelter