4 ms·

Don’t passenger planes already have huge cargo holds for all the luggage? Would it really be that hard to stuff that space full of cargo?

by Swizec 7y ago

toomuchtodo 7y ago
Not comparable to dedicated cargo aircraft.
- remarkEon 7y ago
  Why? I'm genuinely curious. Obviously total cargo volume is lower. Is there some regulatory concern that makes them "not comparable"?
  - jldugger 7y ago
    I'm guessing they do a lot more pallet shipping, and your typical passenger jet isn't prepped to load / store / unload that versus luggage.
  - adwww 7y ago
    The volume vs weight probably comes into play as well. Without passengers, passenger aircraft probably run out of volume capacity long before they approach their max take off weights. Whereas I think with dedicated cargo aircraft, it is usually the other way around - weight is the main limit, less volume.
kzrdude 7y ago
Passenger planes already take cargo as part of normal flights yes! Now there are less passenger flights, so less capacity there! And less passengers to make the flight break even with people + cargo paying.
Frost1x 7y ago
I would guess typical passenger planes have significantly smaller cargo stores than cargo planes so the layout may not be good for efficient cargo transport (outside of course... people as cargo). You'd allocate the volume in the aircraft very differently I imagine for cargo than passengers. I also suspect passenger planes were already using any leftover cargo from passenger cargo storage for commercial cargo transport to begin with. Two potentially very different optimization problems.
- mhb 7y ago
  When airlines are flying people across the country for $13, it makes all of those look like second or third order effects: https://news.ycombinator.com/item?id=22731785 https://news.ycombinator.com/item?id=22731785
roywiggins 7y ago
Yup, they're already doing that: https://www.forbes.com/sites/jamesasquith/2020/03/28/commercial-airlines-are-now-operating-cargo-only-flights/#772ff98b6f0e https://www.forbes.com/sites/jamesasquith/2020/03/28/commerc...
fragmede 7y ago
It's not hard, just more expensive. I imagine not having 200-some people paying, let's say $150, would mean air cargo would have to cover the $30,000-ish difference. There's additional cargo space because the baggage hold is no longer taken up by passenger baggage, but with airlines charging passengers $50/bag, we might be able to guess at the opportunity cost to airlines for taking something the average size and weight of a passenger's checked bag.
- CPLX 7y ago
  > It's not hard, just more expensive. I imagine not having 200-some people paying, let's say $150, would mean air cargo would have to cover the $30,000-ish difference. I think you are drastically underestimating the typical revenue of a long haul or international flight. A good starting point is RASM, or average revenue per available seat mile. For the airline industry a reasonable benchmark for that is about 15 cents, or so. So multiply the number of seats on the plane by the number of miles and you'll get something that's at least in the same order of magnitude for passenger revenue on a flight. Since we know air freight only really makes sense for long distances or over water -- you're going to be using a truck to get medical supplies from Dallas to NYC, and it will take less than 24 hours -- let's pick a good example route: HKG > LAX on a 767, a standard wide-body 7,243 miles x 375 seats x $0.15 = $406,912.50
  - Baeocystin 7y ago
    Not the person you were replying to, but that is definitely much higher than I would have guessed. How do you derive the $0.15 / a mile you used as a rough estimate?
    - CPLX 7y ago
      I mean it just kind of has to be higher for anything to make sense. The depreciation/fixed costs of operating a 767 for an hour is around $10k plus another $20k or so for fuel. That's a couple hundred grand for an 8 hour flight before you even get started with the expense of actually running an airline as a business. So we know the post guessing $30k in passenger revenue for a typical flight is in the wrong order of magnitude. For the number I kind of picked 15 cents out of my ass, it's a number I've seen in the past year in earnings reports for the majors and it easily gets us into the basic range we're talking about. Just google the terms RASM, PRASM, and CASM and you'll find a ton of info, that's the basic jargon used in the business to come up with info of this type.

Don’t passenger planes already have huge cargo holds for all the luggage? Would it really be that hard to stuff that space full of cargo?

by Swizec 7y ago

Don’t passenger planes already have huge cargo holds for all the luggage? Would it really be that hard to stuff that space full of cargo?

toomuchtodo 7y ago

Not comparable to dedicated cargo aircraft.

remarkEon 7y ago
Why? I'm genuinely curious. Obviously total cargo volume is lower. Is there some regulatory concern that makes them "not comparable"?
- jldugger 7y ago
  I'm guessing they do a lot more pallet shipping, and your typical passenger jet isn't prepped to load / store / unload that versus luggage.
- adwww 7y ago
  The volume vs weight probably comes into play as well. Without passengers, passenger aircraft probably run out of volume capacity long before they approach their max take off weights. Whereas I think with dedicated cargo aircraft, it is usually the other way around - weight is the main limit, less volume.

kzrdude 7y ago

Passenger planes already take cargo as part of normal flights yes! Now there are less passenger flights, so less capacity there! And less passengers to make the flight break even with people + cargo paying.

Frost1x 7y ago

I would guess typical passenger planes have significantly smaller cargo stores than cargo planes so the layout may not be good for efficient cargo transport (outside of course... people as cargo). You'd allocate the volume in the aircraft very differently I imagine for cargo than passengers. I also suspect passenger planes were already using any leftover cargo from passenger cargo storage for commercial cargo transport to begin with. Two potentially very different optimization problems.

mhb 7y ago
When airlines are flying people across the country for $13, it makes all of those look like second or third order effects: https://news.ycombinator.com/item?id=22731785 https://news.ycombinator.com/item?id=22731785

roywiggins 7y ago

Yup, they're already doing that: https://www.forbes.com/sites/jamesasquith/2020/03/28/commercial-airlines-are-now-operating-cargo-only-flights/#772ff98b6f0e https://www.forbes.com/sites/jamesasquith/2020/03/28/commerc...

fragmede 7y ago

It's not hard, just more expensive. I imagine not having 200-some people paying, let's say $150, would mean air cargo would have to cover the $30,000-ish difference. There's additional cargo space because the baggage hold is no longer taken up by passenger baggage, but with airlines charging passengers $50/bag, we might be able to guess at the opportunity cost to airlines for taking something the average size and weight of a passenger's checked bag.

CPLX 7y ago
> It's not hard, just more expensive. I imagine not having 200-some people paying, let's say $150, would mean air cargo would have to cover the $30,000-ish difference. I think you are drastically underestimating the typical revenue of a long haul or international flight. A good starting point is RASM, or average revenue per available seat mile. For the airline industry a reasonable benchmark for that is about 15 cents, or so. So multiply the number of seats on the plane by the number of miles and you'll get something that's at least in the same order of magnitude for passenger revenue on a flight. Since we know air freight only really makes sense for long distances or over water -- you're going to be using a truck to get medical supplies from Dallas to NYC, and it will take less than 24 hours -- let's pick a good example route: HKG > LAX on a 767, a standard wide-body 7,243 miles x 375 seats x $0.15 = $406,912.50
- Baeocystin 7y ago
  Not the person you were replying to, but that is definitely much higher than I would have guessed. How do you derive the $0.15 / a mile you used as a rough estimate?
  - CPLX 7y ago
    I mean it just kind of has to be higher for anything to make sense. The depreciation/fixed costs of operating a 767 for an hour is around $10k plus another $20k or so for fuel. That's a couple hundred grand for an 8 hour flight before you even get started with the expense of actually running an airline as a business. So we know the post guessing $30k in passenger revenue for a typical flight is in the wrong order of magnitude. For the number I kind of picked 15 cents out of my ass, it's a number I've seen in the past year in earnings reports for the majors and it easily gets us into the basic range we're talking about. Just google the terms RASM, PRASM, and CASM and you'll find a ton of info, that's the basic jargon used in the business to come up with info of this type.