CRJammin

What's the reason for no jumbo's at the largest freight airline in the world? I saw a ton of Boeings (with 4 engines) at Tokyo Narita last week, and noticed only trijets for FedEx.

Is this aircraft too expensive to operate? What other reason would explain your avoidance of the venerable Boeing jumbo's? Thanks! Over to you pro's-

HSLD

Whats that phrase - Been there done that?

http://www.airliners.net/open.file/1177472/M/

"Federal Express" has operated 747's in the past, although why feed 4 motors when 3 will do? As the Whale gets more efficient, maybe the extra cubes and gross wt. will be more attractive.

This from an outsider looking in (said another way - I don't know why).

md11phlyer

I'm sure someone else has a better answer to this, and it may have been a thread in the past, but it has something to do with our AMJ containers and not being able to utilize all of the cargo space.

42GO

Its really pretty simple From Freds standpoint.....

Every engine above 1 decreases A/C reliability by at least 1% Thats first.

Second, The 727, 737 we used to have, in fact most regular tube A/C only take a certain size container that is common between them all. The 747 has a huge volumn, but only usable if you manually build pallets that use that space. To have pallets that you can use in ALL of our A/C and utilize all the space you can't use manual building of pallets or some of the larger builds that you can use to utilize the space in a 747. That creates inefficiency in 747's for US.....Lots of world cargo carriers use 747's because they have time to build pallets to use that space. WE DON'T.

Its all about utilizing space efficiently and quickly.

MaydayMark

I've been to Shanghai several times. While we are pushing back, a UPS 747 on the next parking bay, also going to Anchorage, AK is pushing back at the same time. After the pushback the 2 jets are facing each other on the taxiway. I've asked the UPS crews how much freight they have. Their answer: About 180,000 lbs (almost exactly the same as my MD-11).

So ... the 747 uses approximately 33% more fuel to carry the same amount of freight the EXACT same distance.

I guess that says it all ... that, and as someone else said, more engines increases the chance that you'll have an engine problem preventing departure.

vagabond

Given the logical explanations above, I'd like to know why carriers continue to use the 747 then. I once posted that I'd like to fly as a passenger on one of these freight trains, but was told it was not possible. I think I could make myself very comfortable on the upper deck with its lavatory, bunk bed and chairs.

42GO

Most carriers have time to build larger pallets to use the available room in the 47....we don't
as to riding, most carry haz cargo and can't carry passengers

MD11Fr8Dog

Haven't you heard? There's no money in 747s!

Actually, mostly a container issue! With the containers we use, the 747 will not bulk out, lots of dead space. If we palletized all the freight for the 747, it doesn't transload so easily to the rest of the fleet.

CRJammin

Thanks to all the responders. That actually makes a lot of sense why a jumbo isn't necessarily needed in your operation. Never thought about the extra space that's not used in the bubble on top and the empty area in the nose, plus the sides.

hyperone

CRJammin, I found this article on the internet a while back. It's a pretty good explanantion of why the MD-11 is preferred by Fedex.

What Makes a Good Freighter Aircraft

I claim no credit or blame for this info: I just found it after a Google search.

What makes a good freighter and what makes a good passenger airliner are not necessarily the same things.

When selecting a freighter, the operate looks for an aircraft with a very large spread between MLW (Max Landing Weight) and EW (Empty Weight). This is the amount of cargo that can be carried. Freight operators are looking for a large spread as a proportion of the EW, or how much dead weight you have to carry per pound of cargo. For large freight volumes, the MD11, DC10, 747F and even DC8 is very attractive in this regard.

As it turns out, for most common cargo loads, the MD11/DC10 run out of lift and cargo capacity (volume) at about the same time. The 747's tend to run out of lift before they run out of volume.

So a 777 or A330 or even 747 may be able to carry the cargo further, but the reality is that cargo does not mind if it takes 18 hours to cross the Pacific Ocean or 14 hours, and cargo does not mind what route it takes - passengers do and they need to be fed and entertained along the way.

So for freight operations, carrying a larger amount of freight and less fuel, and then refueling enroute, can make for more efficient operations than long distance point to point operations.

The other number that is of interest to freight operators is the ratio of fuel burn per hour / (MGTW-MLW). This is basically the range, and as long as this number is 5100 miles, it works well for freight ops. Remember that freights tend to operate between freight hubs, so the longer runs tend to be such as ANC-HKG or HNL-SYD. Look at the operations in/out of ANC and HNL each night and you will see how they operate as freight hubs.

On the other hand, passengers operations require longer range non-stop services. Passengers don't want to stop in ANC or HNL for fuel between USA and Asia.

So if we consider the operational numbers for a passenger MD11 flying, say LAX-HKG, we find EW=295,000 lb, MLW=440,000 lb, and MGTW=630,000 lb. Any flight that consumes more than 190,000 lb of fuel is converting payload into fuel at a rate of about 3lb/mile. LAX-HKG is about 15 hours much of the year (due to winds) and at about 16,000lb/hr fuel burn plus gound and climb usage (say another 15,000lb), we will consume about 255,000lb of fuel.

Now subtract this 255,000lb fuel from MGTW and you get 375,000lb max landing weight, of which about 10,000lb will be fuel reserves. This leaves us a total of 70,000lb of usable payload for passengers, cabin amenities, luggage, catering etc. This means we have a severe passenger restriction for this flight.

If you perform this same long-haul non-stop passenger service with a 747-400 (as CX does), you will consume about 330,000lb of fuel, and need about 12,000 reserves, so 875,000lb (MGTW) less 342,000lb fuel give us 533,000lb MLW against a EW of 398,000lb, or 135,000lb uplift capacity to work with instead of 70,000 lb for the MD11, which is a whole lot more realistic and viable.

These numbers are much more attractive for the B777 and newer A340's for non-stop long haul passenger operations. Hence the demise of the MD11 as a passenger airliner, while it continues to be an admirable freighter.

Now suppose I want to fly freight LAX-HGK non-stop. MLW of my MD11F = 480,000lb and EW = 265,000lb, while MGTW = 630,000lb. We are still going to consume 255,000lb of fuel and require 10,000lb fuel reserves, so I have 365,000lb MLW. Take away the EW and this gives me 100,000lb of cargo payload.

However, what happens if I choose to give my cargo a break in ANC on the way? This will add about 200 miles to the flight, out of more than 7000 miles total, and of course we burn more fuel for the extra takeoff and landing, as well as about 2 hours additional time.

LAX-ANC is about 2350 miles and will take about 5 hours, burning 90,000lb of fuel. Since this 90,000lb of fuel is way less than the spread of MLW and MGTW, this sector is limited only by max landing weight. That means my payload can be the entire spread between EW and MLW less the required fuel reserves, so I can carry about 206,000 lb of cargo.

ANC-HKG is 5080 miles and against prevailing winds is likely to take about 11 hours, consuming about 175,000lb of fuel, plus 15,000lb for ground and climb out, plus 10,000 reserves, making fuel requirements about 200,000lb. This makes the payload 430,000-265,000=165,000lb (MGTW-InitialFuel-EW). So my two-hour fuel stop in ANC has increased my payload by 65%, while fuel costs rise about 10% and crew costs up slightly.

But passengers would not appreciate the 2-hour fuel stop in ANC! Freight does not complain, and does not need toilet breaks etc.

Freight operators like Fed-ex that get very good utilization out of their aircraft ensure that the operating cost efficiencies of their new MD11's (for freight ops as described above) outway the capital costs. For freight operators that have much lower aircraft utilisations, the capital costs are a more significant function and they will tend to look for less expensive purhcase costs and older DC10, B747, A300 and even DC8 aircraft fit their needs better.

So MD11's make good freights so long as you don't try to fly them further than the spread between MGTW-MLW. 777 makes a great pax airline because passengers don't want to take an extra 2 hours to fly long-haul ops.