I'll be flying Condor Airlines in a few months: LAX to Frankfurt. I'll be taking a Bike Friday folding bicycle and using their canvas bag.
From
https://www.condor.com/us/flight-pre...-equipment.jsp :
"....bicycles are only transported packed. We recommend bicycle cases or bags as packaging"
"Dimensions: max. length 200 cm x width 40 cm x height 100 cm or length 300 cm x width 40 cm x height 60 cm. Anything higher, longer or wider must be registered with
customer service (phone / WhatsApp).
Weight: up to max. 30 kg."