what is the {start time} for {Cathay Pacific} has {item operated} as {Bristol Britannia} ?
When Cathay Pacific started to do business in the Bristol Britannia, what was the date?
When did Cathay Pacific begin to operate the Bristol Britannia ?
SELECT ?g WHERE { ?d property:start_time ?g . ?d property:item_operated resource:Bristol_Britannia . resource:Cathay_Pacific property:item_operated ?d }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q32141> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P121> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q917907> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q32141 p:P121 ?s . ?s ps:P121 wd:Q917907 . ?s pq:P580 ?value}