There is the Southwest commercial where they state that their 737s fly at an average speed of 590 mph.
Yet the brochure I just got from a SW flight shows the 737 speed as 544 mph.

So for fun I set them an email questioning that, fun not serious, and got the response that , every claim in this spot has been approved through all proper channels.

So 590 mph seems a bit fast.

Just curious.

__________________
KLK, MCSE

1990 500SL

I was always taught to respect my elders.
I don't have to respect too many people anymore.

Boeing's specs for the 737 family quote mach .785 or .78 @ 35,000 depending on the model which converts to around 593+ MPH.

Edit:

The calculator I used didn't account for altitude so the 593 MPH would be at sea level.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

EDITED:

The commercial is untruthful. There is no possibility of the 737 averaging 590 mph without a tailwind.

Cruise speed?
Max speed?
Airspeed?
Ground speed?
What speed, I need?

Most of the newer 737-700s have a max speed of 470ish kts. That’s about 540ish mph.
That’s the max speed the aircraft can fly (certified) through the air.
Their cruise speed is something like 450ish kts. That’s about 515-520ish mph.
That’s all standard day figures for the aircraft itself. No winds. Straight and level.

Now if they go up and catch a 100+ mph tail wind. Their cruising speed over the ground can easily break 590 mph. That number is not too fast.

The brochure is probably giving you the aircrafts max speed.
The commercial is probably giving you their average ground speed.
(At altitude)

Both are accurate numbers. Just a bit confusing when they don’t tell you exactly what speed they are talking about.

__________________
1980 300D - Veggie Burner !

The specs call a cruising speed of .785 Mach. However they also call a cruising speed of only 514 mph. With the speed of sound at 768 mph...........I'm missing something here...........

EDIT: I figured it out.........the speed of sound at 35,000 feet is approx. 690 mph. .785 Mach gives a speed of 541 mph.

So, clearly SWA is untruthful. The aircraft cannot average 590 mph under any circumstances without a tailwind.

Well thanks guys.

So I guess the definition is air speed or ground speed.

It was just a curiosity.

Thanks

__________________
KLK, MCSE

1990 500SL

I was always taught to respect my elders.
I don't have to respect too many people anymore.

Like missing that the .785 is calculated from CAS and TAS at a specific altitude.
And the 768 is in 68 deg. air.

__________________
1980 300D - Veggie Burner !

Oops...
I see you got it.
Good job.
Never mind.

__________________
1980 300D - Veggie Burner !

You're quite welcome.

BTW -
When you hook up with the aviation nuts on this forum...
NOTHING is handled as “just a curiosity.”

__________________
1980 300D - Veggie Burner !

Thanks..........yep, the figures were too disparate to ignore..........

Why would you say that?
Most of their flights could have one hell of a tail wind.
They will fight for the best winds, tail or head.
Their average speed at altitude could easily average 590.
(Especially for the certain flights they used to make the commercial data from.)

A bit misleading, perhaps. But not clearly untruthful.


Also - Don’t ever mix the aircrafts certified standard operating specs with its actual flight data. They seldom, if ever, jive.

__________________
1980 300D - Veggie Burner !

I'm not believing that they can makeup 50 mph.........on average...........for the entire fleet...........with tailwinds.

They fly all routes in both directions several times in a given day. This tends to minimize any benefits from the wind.

The statement is untruthful.

You are correct in your thinking.
However...We're talking advertising here.

So once again I’ll post:
(Especially for the certain flights they used to make the commercial data from.)

They didn't have to tell you that the 590 is average for their LA to NY flights only.

If I told you that I flew faster than the speed of sound on a trip the other day, would that be a lie? Think about it.

No reason the ad can't have a little note in very small print that says something to the effect of: Based on east bound routes longer than 750 miles.

__________________
1980 300D - Veggie Burner !

Of course..........if you qualify the statement...........anything can become the truth.

I take it at face value...........fleet average.

On that basis, it's untruthful.

I took a DC-10 from LA to NY. Total time wheels up to wheels down was 4:10. 2451 miles at an average speed of 589 mph. I still can't believe it and I was on it.

I hear ya.
But we’re talking advertising here.

You can question it. And they can come right back with: "That’s the fleet average for east bound flights with cruise power set descents from cruise altitude to the first 5K feet lost mark."

And then all you can say is: "Huh?"

__________________
1980 300D - Veggie Burner !