Larry,
I think those pilots reacted just as anyone would have reacted. They flew out, expecting/hopeing to find Hermes...... Remember, they were not quietly analizing photos, they were in combat, being shot at, scared, trying to keep formation, preparing their aircraft for attack, looking for enemy fighters......
At best they caught only a quick views of the ship, they expected to see HMS Hermes and in their mind they saw HMS Hermes.