Pop quiz: When must you file an alternate? That’s an easy one, we all know the rule about needing 2000-3 one hour before and after the ETA. Next question: When do you file an alternate? Probably the most common answer is, “I always file an alternate.” Fair enough, it’s never a bad idea. Now, regulations aside, why do you file an alternate? Naturally the response is: In the event the weather’s gone down too low at the destination and we need somewhere else to go. Right up there is an unexpected loss of equipment or a navaid required for an approach. And while the regs are also designed to provide a backup for lost communications, this often serves as a distant third, ’cause these days we’re just not all that worried about that.
So how do you choose that alternate? Another easy one; it’s the 600-2 or 800-2 rules with an ILS or not, respectively. Does your favored alternate have that tried-and-true ILS? Yep, so off you go. That’s how it’s done 99 percent of the time. But this super-quick method for choosing alternates doesn’t always provide the safety net it was designed to have. That’s because these rote numbers tend to have us file alternates that are 1) near the destination and 2) 600-2. For the rare times when it’s needed, you’ll want a well-thought-out alternate plan that doesn’t back you into a corner.
