The fuel selector and it´s position is one of the negative points in my airplane. In order to switch it, I need to lean forward quite uncomfortably (particularly with my “overload” in front…) and I can barely reach it out of the normal position. In order to do it properly, I have to move around quite a bit. Additionally to that, the fuel switch positions are Right – Off – Left. So if you turn it one quarter, it´s gonna get silent up front. Some Mooney pilots have made themselfs a T handle to overcome that. They changed the handle position in the modern Mooneys thankfully, so the 201 and following don´t have this handicap.
Consequence is, the fuel switch is not something I want to handle in a busy phase of flight. That is why the fuel switching usually happens in descent, if necessary, before the actual approach starts. I got the point in the pre-descent checklist, where I determine on which tank to land. With normal ops, it is simply not necessary to operate it thereafter, as there is plenty of fuel available in both tanks due to the Mooney doctrine in fuel useage as laid out in the POH:
- Take off and climb up to 1st hour on the fullest tank,
- then fly the 2nd tank empty and
- return to the 1st tank for the remainder of the flight.
Consequently, what happens most of the time is that either by the time of the top of descent I will be on the 2nd tank (less than approximately 3 hours of flight) and will switch back to the first, which by then will have more fuel. Or, on short flights, I will still be on the first, so therefore the other one is fuller and I switch to it. With the doctrine they use, switching during intermediate or final approach is not necessary usually at all, most switching happens in cruise. This also has the advantage that if something is amiss with the contents of one tank, you´ll find out while you have time to deal with it.
Final reserve for my operations is 6 USG, so the landing tank should never go below that in any event. After a “long haul”, the ideal picture should be the landing tank > 6 USG and the other one empty. Again, this most of the time will not require a switching after the top of descent.
Why not allow some imbalance in the tanks and land on the fullest, running the other tank as low as possible.
Should you need to side slip you may find on some types this isnt such a good idea with a very low level of fuel.
