Until recently, we used to have this one problem that was a nightmare to deal with. A student would show up with his/her own multi engine airplane and would ask us to train in their airplane for the CFI, CFII or MEI, or even a commercial/flight instructor combination course. In any case, the training had to be conducted in the applicant’s own multi engine airplane.
The training was never an issue. As a flight instructor with a multi engine rating, we are authorized to teach in any make/model if a light twin airplane, provided we have at least 5 hours PIC time in that make/model of airplane. With so many years of teaching in various airplanes, we usually have just about all the light twin airplanes in our logbooks, with 5 hours minimum under the PIC column. And every now and then, if a new one shows up anyways, nothing to worry. We are always so excited to learn and fly another “new” light twin anyways.
The problem that’d show up was, not being able to find a DPE who would have a Letter of Authorization (LOA) from the FAA to conduct a checkride in that make/model. Now, we’d just be stuck at the mercy of the local FSDO to schedule a ride with one of their inspectors (and with the current short staffed situation), which could be as long as a month or more in the future!
The DPEs had to obtain an LOA for each make/model; by demonstrating their skills to an FAA inspector in flight, in each make/model of light twin they wanted to conduct a checkride in. And then do an annual proficiency check in each make/model (on a rotating schedule) with the FAA. This process would discourage DPEs from having more than 2 or 3 makes/models on their LOA at any given time.
Now, their LOA allows then to conduct a checkride in ALL light twins! At last the issue is rest to peace, and the lawmakers have realized that they can look elsewhere to prevent accidents and increase safety.