Tinstaafl
So far as I know, the B747 was the first US airliner equipped with a standby attitude indicator straight from the factory as standard fit.
The Boeing 707 and Lockheed TriStar offered several switching arrangements for alternate power for attitude/HSI indicators, depending on customer requirements.
For example, some of the 707's that I operated had no alternate source for the F/O's attitude indicator. If the number two radio bus or the number two VG failed, he had no attitude information. PanAmerican and TWA aircraft had more redundant arrangements as I recall due to the much longer overwater sectors that they operated.
Todays pilots in shiny new metal have it too easy...
