What does your CFI who signed you off for the ride say? You said the change of FSDO was a long story and they may be far away, but you’re going to need their help.
I’m not making this argument personally but here’s what you’re up against:
As far as the systems knowledge, you’re still required to perform to your Commercial Pilot certificate on a CFI ride. Systems knowledge is mandatory.
FAA may not care in the slightest that the DPE asked systems questions, if the standard is that you need to be teaching in that aircraft and know it cold. Systems knowledge isn’t dumped because it’s an add-on.
As far as the PTS table for add on rides, I’ve seen an occasional mistake made where an item not in the table is re-tested that’s not required. The Commercial certificate standard still applies.
You might find a sympathetic ear at the FSDO (or whatever they’re calling it these days) about the add on table or you might not. Can you teach those items in both types of aircraft? Would you have to with a student? See where this leads?
You already have the Commercial certificate so, anything you could do for that ride shouldn’t have been too difficult for the CFI ride. You do have to demonstrate it and teach it at the same time as flying it, though.
Your instructor will probably have to back you and put their signature they have, that said you were fully prepared for the ride, on the line.
I wouldn’t start a war with an examiner and involve the FSDO if you don’t have any support from them.
Friendly internet advice... which is worth about as much as you paid for it. But you really need the advice of those who trained you and signed your logbook before you proceed, in my opinion.
You can complain to the FSDO about the items tested and they might say, “Those items would be expected of a CFI candidate whether they’re on the table or not.”
Again, not necessarily my personal opinion. I’d rather folks follow the rules, but I’m explaining how this could go down for you.
Here’s another possibility. FAA says okay, maybe there’s something going on here. We’ll send an FAA person to give you the checkride tomorrow.
You ready to fly with a Fed? They can ask anything they like... Are you ready to fly and perform to the standards of all of your certificates and ratings tomorrow?
Just thoughts. Take or leave as you wish. Proceed with caution.
Was it truly unfair, or just mildly out of the ordinary, but well within the things you should have known for this checkride, anyway? Don’t let frustration cloud your judgement in this matter. Humility is critical.
Okay I’ll give a personal opinion now.
I think not knowing the pitot static system of an aircraft you’re teaching in, is probably a fail no matter what. (There’s really only two popular ways for manufacturers to employ pitot system drains on most of the popular twin trainers. You didn’t say what you flew but unless it was an oddball, there’s only a couple of common types. You could have talked about those two while you looked up the details in the POH. And on older aircraft, you won’t find it in the POH anyway. It’s not in mine. You have to just look at the pitot tube and see it. It just “is” one way or the other.)
The PTS add on table being busted by the examiner is probably also not something that should have been any big deal. It MIGHT earn you a re-ride but you’d better be very well prepared for that one.
It could be a bear of a ride.
As far as the disappointment and possible career implications... you’re attitude will make a significant impact on that. Hiring is as strong as it’s ever been in my lifetime. I suspect with patience and effort you’d get the opportunities you desire and have a chance to explain the failures and what you learned from them to a recruiter in this market. Twenty years ago, maybe not. Chin up. Learn and grow.
It sounds contrite, but sometimes some doors close which leads to something better anyway. Roll with the punches and be smart about how you react to them.
