Let me give this another crack... But first some disclaimers: the text to me are unclear in some parts because it's colloquial, and the fact it starts out with a rhetorical question doesn't help. Also it seemed to be missing some crucial punctuation marks and conjunctions, which added to my confusion. I will add what I believe to be missing or implied in parentheses.
So here it goes, begin translation:
Countless test flights have already been carried out, yet we are still waiting for the first (official/public) flight. What is there to be afraid of? Perhaps a fear of embarrassment if the first public flight fails? The first official flight will not be announced to the public until everything is completely ironed out and is guaranteed to succeed. (Meanwhile), if the plane is spotted by netizens, (the military) will deny its existence by saying the witness has misidentified the plane and didn't see what he/she claims to have seen, (or) profess ignorance by pretending to not have heard anything about the plane being spotted, (or) state that there is no official information at this time and has no comment. Attached is a fake photo (to give you a clue on what kind of plane I'm talking about); I know it's a fake photo, so no need for you guys to point that out in the comment section.
End translation.
To summarize:
1) The official first flight of the stealth bomber will not be announced to the public until the PLAAF is certain that it will go smoothly. To that end, numerous unofficial test flights have already taken place and more will be carried out.
2) Should the bomber be spotted prematurely, the military will deny, obfuscate, or clam up.
3) The author never once explicitly stated what kind of plane he was talking about. Instead, he gave an unmistakable clue by posting a photo of the B-2 stealth bomber.
End summary.
Please correct any mistakes you see in my translation and interpretation and point out anything I have missed. It wouldn't surprise me if I have made serious errors in translation, so any correction is highly welcome.