Tailwinds
 

When flying with a substantial tail wind, do majors stay with the original planned mach speed, or do they throttle back (saving gas) and get to the destination "on schedule"?

Thanks!

It all depends on if it's Friday or not...

When I used to fly charter, west coast to east coast, we would climb up to cruising altitude ASAP and then plan for an "economy cruise" power setting. In most cases we were able to make it non-stop and it would only add about 10-15 minutes to our trip.

Cheers

I'm sure in the airplanes with VNAV, the dispatcher will plan the flight at a lower Cost Index so that they can take advantage of the winds, fly a slower mach number, save fuel and still arrive on time.

We get paid by the minute. Fly as slow as possible to maximize pay. (jk):)

"Center, speed our discretion? We're early." :D

Do I have a tight commute to make? That dictates a lot!

I've never seen a dispatcher's note on the flight plan that said, "I planned you at M.76 because you have a 150kt tailwind."

On the 777 we use pretty much the same cost index all the time, which usually results in a cruise of around M.825, headwind, tail wind, or no wind. (the FMC will go a little faster into the wind, a little less with tail, but not much) The only problem is, Customs in ATL doesn't open until 05:30, so they won't let you open a door, or even park, until 05:30...so if you get in earlier than that, you sit on the ramp with an engine running.

I believe at DL we are going to a more aggressive cost index program where you'll see much more dramatic cost index changes depending on winds and arrival times.

We actually had such a huge tailwind the other day coming from IND-ATL that we delayed departure by 20 minutes because of gate availability. We still got in 15 minutes early....

It's all fine and dandy to pull it back for fuel savings, etc.

Till you're going somewhere busy and center asks why you're going so slow. At this point it's either 1) Speed up because you're screwing up flow into the airport or 2) Vectors off course/Ait change because you're screwing up flow into the airport.

Not sure what you're point is.

Go slow if it's more efficient until you need to not go slow. It's not that hard. The fuel you saved while you were riding the wind is worth it. Pick it up when you need to for the flow.