Are Airlines Loading Less Fuel, Or Are There More Delays?


“Pilots Using More ‘Fuel Fudge-Factor’ To Protect Passengers/Crew” … 6424aa6cd&

"At Newark Liberty International Airport, just five flights landed under minimum or low-fuel conditions over a six-month period in 2005. In a similar period this year, 73 flights came into the same airport with minimum fuel.

The report also said 10 flights had to declare the more serious emergency fuel situation, of less than 30-minutes fuel reserve." :open_mouth:


My opinion is that the airlines are following the letter of the law and not the spirit. If the regulations say they only need 30 minutes of reserve fuel then that’s all they are going to put onboard.

As far as the part about 5 flights in a six month period in 2005 and 73 flights in six months of 2007, I need more data. In order to do a fair comparison, I need to know if the number of flights for the 2007 period was more, less, or the same as 2005. That way I can get an accurate percentage of how many flights reported low fuel.


It costs fuel to carry fuel.
A generic trip departs airport A with 30,000lbs fuel and was planned to burn 25,000 of it enroute to airport B. If they loaded 32,000 lbs of fuel the burn would go up for the exact same flight time. How much depends on the aircraft. As close to the margins as the airlines are running these days it does not surprise me that aircraft are being dispatched with nothing more than required fuel (planned enroute burn plus the various alternates and reserves). Nothing dangerous or sinister about it. With computer modeling of winds and accurate performance data the planned fuel burns are amazingly close.


Ditto G4Driver…It’s all about efficiency…maximizing payload while carrying only the required fuel for the leg and reserves. Airlines have adjusted their schedules for longer times to allow for more efficient cruise speeds. Lately I’ve been hearing alot of low .7X mach cruise numbers when airliners are queried about speed by ATC Centers.


I have noted that too azav8r.
I wonder what the point of diminishing returns is though. In the G4 you can go to the -what if- page in the FMS and see what your flight time and fuel burn would be by changing your speed or altitude (or both). What you find is at some point you end up burning the almost same amount of fuel to slow down than if you had just held your speed. This also does not take into account the extra cost of engine time. So what was the saving? I am sure there are people at the airlines many time smarter than me who have figured it out though.


It appears that airlines may be adding undue risk with their attempt to maximize efficiencies.
As noted in the FAR, protecting the traveling public is the goal, not airlines bottom line.
To quote, "Commercial aircraft have strict rules and regulations about operating in the vicinity of bad weather. Aircraft typically cannot take off unless the visibility at the destination airport is forecast to be at or above a certain distance, usually one-half mile. Moreover, airlines are cautious about aircraft operating in the vicinity of bad weather due to passenger injury. Generally, two-thirds of turbulence-related accidents occur at or above 30,000 feet. In fact, 46 percent of all passenger injuries in flight are due to turbulence encounters, and since 1985 have cost the major airlines more than 37 million dollars in personal injury lawsuits, according to the Department of Transportation. This issue alone would seem to leave most airline operators with no choice but to delay flights when turbulent weather approaches."
What would be the impact of multiple low fuel declarations be at JFK. "Under the current voluntary system, the FAA suggests that airlines hew to a limit of 100 operations per hour at JFK, and during some hours, airlines end up scheduling more than that." … 06-ON.html
With any miscalculation of fuel, might they limit themselves and the PIC to route options in flight and stacking at destination.


I’ll also note that COA flies a lot more overseas B757s, it doesn’t take much of a headwind for those babies to go min-fuel.


  1. Everyone has slowed down, so long as the reduced speed does not cost more fuel for the extra time, you are golden. Generally, flights with tailwinds would slow down the most since the speed added by the tailwind offsets the slower speed and fuel burned at mach .72 are tremendous. The Stage III 737-200 is being operated @ mach .68.

  2. Many airlines are using required winds reporting in air by pilots - the purpose is so this info gets reported to dispatch then they have REAL TIME data on winds and given the number of flights, a pretty good depiction of actual winds which allows them to load fuel almost to the gallon.

  3. ‘Minimum fuel’ is not an emergency state, it merely informs the controller that undue delay cannot be tolerated. The controllers generally then can sort the traffic flow to address the fuel issues. No controller wants the paperwork of an airliner declaring an emergency on their shift, so when an airliner gives a minfuel report they may actually care.

When one of us guys in GA declares minimum fuel they just tell us to land somewhere else and get gas . . .