If your students are having a bad day, you may need to be creative in order to identify the success. You may have to say something like, "Billy, I've never seen anyone get out of an airplane quite as gracefully as that. Well done." That's OK. Just let them experience some form of success, regardless of what it is.
And if you can't find even one thing that your students did successfully, then ask them if they read AOPA Flight Training magazine. If they say yes, congratulate them! In my book, that's a big success.
Have you ever been asked to give a flight review or instrument proficiency check (IPC) in an airplane that you've never flown before? If it hasn't already happened to you, it will sooner or later. What's the proper thing to do in these instances?
I'd be lying if I said that I never did such a thing myself. I have. But here's the catch: In almost every instance, the airplane belonged to a rated pilot who was already familiar with that airplane and current to act as pilot in command.
Since I wasn't required to act as pilot in command, I was along as an aviation consultant, not an expert on that particular airplane. For instance, I gave a flight review in a single-engine airplane with a turboprop engine. I had never flown this model of airplane before, but then again, I wasn't there to do a checkout. I was there to give a flight review to an already rated and current pilot. Nevertheless, I did spend some time familiarizing myself with the airplane - as you should, too. But there was no way I could be expected to know it as well as its owner.
So I preceded our flight review with a statement that's always kept me out of trouble in these situations. I said to the owner, "Since you know much more about your airplane than I do, I'm relying on you to prevent us from doing anything that would exceed its operating limitations or jeopardize our safety."
I always provide a few examples to make sure that the owner of the airplane understands what I mean. For instance, if I ask him to lower the gear, I expect this to occur at or below the maximum landing gear operating speed. If I ask for a go-around or stall recovery, I expect power to be applied in a way that won't overboost or damage the engine. If I ask for a descent, I expect it to be done in a way that won't shock-cool the engine.
The fact is that flight instructors can't always be intimately familiar with every airplane that they fly. As long as the person they're flying with is qualified and capable of acting as pilot in command in that airplane, then flight reviews, IPCs, and general proficiency flights can be conducted safely under these conditions. Of course, if the applicant for these flights isn't qualified or familiar with the airplane, that's a different story. Now the CFI must be intimately familiar with that aircraft before any flight is attempted.