Back in the 90s I sat next to a coworker who could speak but could not hear. (He had had normal hearing into adulthood, then lost it.) He used to use a service, which I understood was provided by a phone company – I thought of it as the phone company, but even by that time this was an anachronism. Whoever provided it, it made it possible for him to handle situations like this, where a service is provided solely by means of a voice telephone line.
Some elementary googgling turns up the (apparently interchangeable) names TTY (TeleTYpe), TDD (Telecommunications Device for the Deaf), and TT (Text Telephone) for this service.
Can anybody – perhaps somebody with a connection to the Deaf culture – give some info about this kind of service, and explain why it wasn’t available for this person? (I don’t think the answer can be “because Lufthansa doesn’t provide it” – in the 90s version, at least, the service was a separate entity that could connect to any voice number.)
