Window for Departure On Long Flights

Source: www.pilotworkshop.com
Featuring Bob Nardiello

Mark:

"Bob, specifically, what do you mean by a window for departure?"

Bob:

"I'm talking about developing, 36 to 48 hours in advance of your flight, options on a departure time which will be based on the weather, the route, stops you might make, fuel requirements, the load you'll be carrying, the altitude you intend to fly. All of those will be opposed to your aircraft capabilities to develop a window for departure."

Mark:

"So when you're planning an IFR flight, you don't have a fixed departure time in mind?"

Bob:

"That's right. What you want to do is allow yourself enough time in your flight planning to work around any significant weather issues that might occur on the day of departure. For example, if you need to be at Gary, Indiana, at 4:00 p.m. in the afternoon you should not plan your flight for departure at let's say 12:00 noon based on a four-hour en route flight. Instead you should develop a window for departure which might extend from 6:00 a.m. to 12:00 noon. And based on weather that particular day you can then have the option of departing at a time which will allow you to avoid, let's say, thunderstorms in the afternoon.

If you don't develop this window for departure you're sort of stuck with whatever weather occurs in the afternoon period. There may be other issues such as high winds forecasted that might influence our departure time. So what I'm suggesting is that you leave yourself options on the departure time, which will allow you to work around weather issues."