highflier92660
Posts: 543
Joined: Mon Apr 05, 2004 2:16 am

UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 12:50 am

There were several articles today about United Airlines reducing the cruise speeds of their aircraft as a result of spiraling jet fuel prices. Other airlines were attempting to reduce costs by lessening the "tankering" on North Atlantic routes. Since several aircraft are already flying at optimum LR speeds (B-757/767 Mach .80 B-777 Mach .84) how slow are they going to fly them?
 
CPDC10-30
Posts: 4681
Joined: Wed Feb 02, 2000 4:30 pm

RE: UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 1:27 am

Simply lowering cruise speeds won't offer any cost savings by itself - there are many other factors that come into play namely connecting passengers, crew, aircraft utilization etc. These factors are already taken into account by the flight planning department and they make the decision on route, cruise speed, desired flight level etc. At AC for example, it is not unusual to run the 763 at M0.83-.84 transatlantic if they are running late or have pax with tight connections.

So does this mean essentially that the flight planning process has been changed to strictly give preference to saving fuel?
 
artsyman
Posts: 4516
Joined: Wed Feb 28, 2001 12:35 pm

RE: UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 1:30 am

Other airlines were attempting to reduce costs by lessening the "tankering" on North Atlantic routes
****

Continental are tankering on every route possible, not just the North Atlantic. The north Atlantic only accounts for a low % of the total flights, where as the rest of the network is thousands of flights.

Tankering saved Continental 1.2 million last month. It is something they are working hard on these days.

J
 
User avatar
solnabo
Posts: 5019
Joined: Fri Jan 11, 2008 8:53 am

RE: UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 1:54 am

That will make it longer time in the cabin for pax. Wonder what they think?
The tickets has to be cheaper, true of false?

Hejdå Big grin
Airbus SAS - Love them both
 
Sinlock
Posts: 1631
Joined: Fri Dec 22, 2000 12:55 am

RE: UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 2:44 am

I taking a guess here,

I'd take it that "Tankering" is an airline operating a flight taking a full load of fuel in order to avoid the higher fuel costs in other countries. I'd also the guess the same for return trips from places that have lower costs.
 
dbo861
Posts: 864
Joined: Tue May 18, 2004 2:20 am

RE: UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 4:53 am

The price for Auto gasoline is going down, is the price of Jet fuel forecast to go down?
 
BA
Posts: 10134
Joined: Fri May 19, 2000 11:06 am

RE: UA Revising Cruise Mach Numbers

Mon Jun 14, 2004 5:06 am

Every aircraft has an optimal cruise speed at different altitudes, temperatures, and other varying conditions.

When you fly above that optimal cruise speed, you lose fuel efficiency. When you fly below that optimal cruise speed, you will also lose fuel efficiency.

Many factors determine the aircraft's optimal cruise speed at the varying conditions, from the wing design, weight, etc.

Modern aircraft computers are capable of calculating the optimal cruising speed by taking into account the varying conditions, constantly following it and making any necessary adjustments.

I assume UA and other airlines will start following optimal cruise speeds more often now.

Regards
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran