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Reading Why do cargo airlines frequently choose passenger aircraft rather than aircraft designed specifically for cargo?, some answers say that cargo aircraft fly less than passengers aircraft. Why?

Camille Goudeseune
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Ian Ringrose
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1 Answers1

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It's due to the overnight parcel distribution model which limits the available operating time. A parcel picked up by 5pm needs time to get a terminal, and then has to get to the destination distribution terminal in time to be distributed and dropped off by mid afternoon the next day.

This means the heavies in the freight business do their flying overnight running between their distribution hubs (being a "Freight Dog" pilot is considered a night shift sort of career with fewer hours flown per year than pax flying, maybe 300-500 hours vs 700-1000 flying pax) so that freight can arrive at distribution points in the morning where it goes out to sub terminals on smaller aircraft during the day, or sent out by truck.

For example, Fedex runs aircraft in and out of Atlanta only between 10pm and 6am. For many years I worked at an airport with a Fedex Terminal and you would wonder how anything got done because all you ever saw during the day was parked MD-11s lined up in front of the terminal, apparently just sitting there, with no freight movements to speak of after about 7 am, except for smaller a/c flying sub-distribution runs through the morning. Well they are actually just waiting for their outgoing freight to arrive and if you happened by at midnight, it was pretty busy and there was a fair number of a/c coming and going.

So a freighter has maybe an 8 hour operating day, whereas a passenger a/c gets flogged like a mule and starts flying at 6 am and runs until 9 pm. Plus the loading and unloading process for pallets is somewhat slower than with self-propelled human cattle getting on and off for you. So you can't really do more than a couple of legs per day.

To provide context, this UPS fact sheet shows a fleet of 255 UPS jets doing 318 daily trips on average

It says "In-Out" trips for that 318 number, so lets assume that's actually 2 legs, 1 in and 1 out, for 636 actual flight cycles. That's only 2.4 cycles per day overall, almost as easy a life for the airplane as corporate.

John K
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    This is fairly specific to US domestic operations. What about international routes (e.g. Cargolux)? They should operate all day, right? – Bianfable Dec 05 '19 at 17:01
  • Also is this why there are much fewer night flights than daytime flights? – user3528438 Dec 05 '19 at 17:21
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    Well, more like North American operations - US/Can/Mex. I can't speak for Europe but I would think that internal cargo operations in the EU would follow a similar model. I am familiar with the conversion of old beaten up Regional Jets into cargo carriers for EU operations, and I remember it was the same kind of thing - low cycles and night flying. The low cycle operations meant that high cycle airframes were marketable. Oceanic operations are another thing entirely I would think. – John K Dec 05 '19 at 17:37
  • @user3528438 you mean pax flights? – John K Dec 05 '19 at 17:37
  • @JohnK Yes, passenger flights. I sleep well on airplanes so I prefer overnight trips more than daytime trips, but I always have hard time finding overnight tickets, e.g. from LA to Chicago. – user3528438 Dec 05 '19 at 17:45
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    A lot of major airports have curfews that ban operations between say 11pm and 6am so "red eye" flights have to be scheduled around those limitations. Also since such a large block of pax, maybe a majority, are traveling on business, and most people don't sleep very well sitting in an airline seat (I certainly can't) it doesn't really work to take an overnight if you have to attend meetings next morning or afternoon with no sleep. So I don't think the overnight demand is really there. – John K Dec 05 '19 at 18:00
  • @JohnK I see. Thanks. – user3528438 Dec 05 '19 at 18:03
  • Unlike passengers, packages don't really mind sitting around in their "departure lounge" for hours (or even a day or two, if it's not overnight delivery) before getting on the plane. – jamesqf Dec 05 '19 at 19:29
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    @jamesqf OTOH, many packages show up early because there was space today to take some cargo sitting around that wasn't scheduled to go until tomorrow. Passengers don't generally work that way. That's why cargo can reliably fill one large plane per day despite uneven demand. – StephenS Dec 05 '19 at 21:23
  • But what about all those packages whose senders didn't pay extra for overnight shipping? – Vikki Dec 06 '19 at 03:09
  • They sit around longer – John K Dec 06 '19 at 03:31
  • @John K: Or maybe not. The shipper probably puts all the overnight parcels in the plane first, then fills up the remainder of the space. So (as happens to me reasonably often) the thing I ordered with "regular shipping" shows up the next day. – jamesqf Dec 06 '19 at 03:52