IFR noob question - enroute turns

[Jeff N]

So, after flying only VFR since the PE beta days, I've recently begun exploring the world of IFR. I've made it up to an I-08 rating in the training program by watching Keith's IFR workshops, some more than once, and reading countless threads on various pilot forums.

However, I've realized that somehow I don't definitively know what I'm supposed to do about enroute turns that are >90°. I'm sure this is elementary, but am I supposed to conduct a procedure turn like when on an approach? Or do I just time my rate 1 turn to put me on course outbound from the fix or VOR by using some technique that I'm not aware of?

[Keith Smith]

If you have equipment that allows you to lead the turn and help you maintain the centerline of the course to be flown, then you should utilize that equipment to the extent possible. Otherwise, If you do not have such equipment, the MEA's for the relevant airways take into account the gradient of the turns if I'm not mistaken, and assume no turn prediction for aircraft on Victor airways. In other words, even if you don't start your turn until passing a particular VOR, you shouldn't hit anything

[Jeff N]

Got it, thanks Keith. I figured that was probably the case but wanted to know for sure.

In case anyone else reading this has the same question, here's a good thread I just found on the subject: viewtopic.php?f=3&t=1316

[Peter Grey]

Otherwise, If you do not have such equipment, the MEA's for the relevant airways take into account the gradient of the turns if I'm not mistaken, and assume no turn prediction for aircraft on Victor airways.

That's not quite correct.

Per AIM 5-3-5:

Without such actions as leading a turn, aircraft operating in excess of 290 knots true air speed (TAS) can exceed the normal airway or route boundaries depending on the amount of course change required, wind direction and velocity, the character of the turn fix (DME, overhead navigation aid, or intersection), and the pilot's technique in making a course change. For example, a flight operating at 17,000 feet MSL with a TAS of 400 knots, a 25 degree bank, and a course change of more than 40 degrees would exceed the width of the airway or route; i.e., 4 nautical miles each side of centerline. However, in the airspace below 18,000 feet MSL, operations in excess of 290 knots TAS are not prevalent and the provision of additional IFR separation in all course change situations for the occasional aircraft making a turn in excess of 290 knots TAS creates an unacceptable waste of airspace and imposes a penalty upon the preponderance of traffic which operate at low speeds. Consequently, the FAA expects pilots to lead turns and take other actions they consider necessary during course changes to adhere as closely as possible to the airways or route being flown.

[Keith Smith]

PG, I should've been more clear, I was referring to operations of typical piston aircraft. It's relatively rare to be flying a 290+ktas aircraft (basically a jet) without at least DME

[Peter Grey]

True, but the last line of my quote is the relevant part. Technically the FAA always wants you to lead turns, but yes in a smaller piston nothing is going to happen if you don't.