Gulfstream Aerospace Corp. will unveil a new business jet on Tuesday that has been developed with the kind of secrecy typically reserved for a military spy plane or the latest smartphone.

The cloak around the project even led one Wall Street analyst to scrutinize satellite photos of Gulfstream’s Savannah, Ga. production facility for clues, highlighting the financial importance to parent General Dynamics Corp. of the project, code-named P42.

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