Flight number with letters?

[flyingcheesehead]

So, my dad's on the way back from a trip tonight and I was watching his Northwest flight on FlightAware - Or at least, I tried to.

The itinerary says he's on Northwest Flight 1177, but they weren't shown as being in the air. So, I check the page for KMSN and find NWA177W as well as NWA1177.

First of all, I didn't even realize they *ever* had a letter in a flight number... I figured it was a typo. So I pulled up KMSN in LiveATC, and sure enough, they checked in as "Northwest one seven seven whiskey." Weird!

So, airline folks - Why would they have replaced the original flight number (1177) with a similar one ending with a letter (177W)? Does the presence of the letter, or the letter W itself, have any meaning?

 

[jmaynard]

I've seen this before when an inbound flight is delayed, but an outbound flight with the same number goes out while the inbound is still in the air. I would assume that a flight number would need to be unique within the system.

 

[Greg Bockelman]

So, my dad's on the way back from a trip tonight and I was watching his Northwest flight on FlightAware - Or at least, I tried to.

The itinerary says he's on Northwest Flight 1177, but they weren't shown as being in the air. So, I check the page for KMSN and find NWA177W as well as NWA1177.

First of all, I didn't even realize they *ever* had a letter in a flight number... I figured it was a typo. So I pulled up KMSN in LiveATC, and sure enough, they checked in as "Northwest one seven seven whiskey." Weird!

So, airline folks - Why would they have replaced the original flight number (1177) with a similar one ending with a letter (177W)? Does the presence of the letter, or the letter W itself, have any meaning?

At UAL, we do that when there is a chance that there will be two identical flight numbers in the air at the same time. Say a flight is running late, and the continuation leaves on time, they will tag an alpha on the departing flight.

But rules have exceptions, and at UAL an inbound flight that connects to an international flight with the same number will get an alpha also.

 

[Let'sgoflying!]

W= "With Dad"

 

[Teller1900]

Just as jay and greg said, we do that too (though we don't have to worry about the international part). Air Wisconsin does that A LOT with the alpha appended to their call sign.