Breakdown of Le décollage devait être à midi.
être
to be
à
at / to / in (general locations) / about (what one thinks about / reacts to)
midi
noon
devoir
to have to / must
Questions & Answers about Le décollage devait être à midi.
Why does devait translate to "was supposed to" instead of "had to"?
Does using devait tell us whether the takeoff actually happened at noon?
What would the sentence mean if it used the passé composé instead (Le décollage a dû être à midi)?
The meaning would change entirely. In the passé composé, devoir expresses either a fulfilled obligation ("had to") or a strong deduction. In this context, it would translate to "The takeoff must have been at noon" (meaning you are guessing or deducing the time based on evidence).
Is it normal to use être for an event happening at a certain time, rather than a phrase like avoir lieu?