# What is the heaviest single object ever to be lifted by aircraft? **URL:** \ **Category:** Factual Questions\ **Created:** [April 24, 2019, 4:38pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999 "2019-04-24T16:38:11Z")\ **Posts on this page:** 13\ **Page:** 2
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [April 25, 2019, 9:36am UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/21 "2019-04-25T09:36:38Z")
> [@Ike\_Witt](#): > > Why did they continue with the plane after the rocket was cancelled? Apparently the current plan is to launch the Pegasus XL, which is a smaller rocket than the Pegasus II. But it should be able to carry three at once. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [April 25, 2019, 12:00pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/22 "2019-04-25T12:00:28Z")
My guess is that Stratolaunch still hopes (or hoped) that a successful development of the airplane would help bring in additional funding and allow them to resume the rocket development. Though Paul Allen was the co-founder and major investor, and he died last year, so the future of Stratolaunch seems even less certain now. ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [April 29, 2019, 1:34pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/23 "2019-04-29T13:34:27Z")
> [@Reindeer\_Flotilla](#): > > The last sentence was a surprise to me, not that the fuel would be the bulk of the weight but by how much. Yea, the SRBs are a column of fuel that are wrapped just enough to stay together. Most of the time. ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [April 29, 2019, 3:20pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/24 "2019-04-29T15:20:07Z")
> [@Dr.Strangelove](#): > > The stages of a rocket are independent vehicles. I see no reason why we can’t count the upper stages and payload of a given rocket as the “object”, with the first stage as the “vehicle”. Especially since the upper stages aren’t contributing to the thrust or propellant when the first stage is active. > > The first stage of the Saturn V weighed 5,040,000 lb fueled, and we aren’t counting that. But it lifted the second, third, and payload as a joined object. Together, they weighed 1,093,900 + 271,000 + 107,100 = 1,472,000 lbs, or 736 short tons (668 metric tons). Oh, goody-you’ve found a loophole. I think it is pretty obvious that rockets are excluded from this list, despite your thinking that I didn’t word it just right. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [April 30, 2019, 2:33am UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/26 "2019-04-30T02:33:14Z")
> [@Czarcasm](#): > > I think it is pretty obvious that rockets are excluded from this list… Why? ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 30, 2019, 4:00am UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/27 "2019-04-30T04:00:48Z")
> [@Czarcasm](#): > > Oh, goody-you’ve found a loophole. I think it is pretty obvious that rockets are excluded from this list, despite your thinking that I didn’t word it just right. It wasn’t intended as a gotcha answer. You went out of your way to state that you meant “aircraft” in a general way that seemed to include rockets (“any vehicle that moves above the ground”). A multi-stage rocket is not a single vehicle–it is multiple vehicles that (usually) operate sequentially. With only minor tweaks (moving some shared avionics), a Saturn V first stage could have lifted a dead mass instead of the upper stages+payload of the full rocket. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [April 30, 2019, 11:47am UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/28 "2019-04-30T11:47:27Z")
> [@Dr.Strangelove](#): > > It wasn’t intended as a gotcha answer. You went out of your way to state that you meant “aircraft” in a general way that seemed to include rockets (“any vehicle that moves above the ground”). Except then the OP said spacecraft were disallowed. “Spacecraft” is admittedly a somewhat vague term, but taking the OP as a whole, do you you honestly believe **Czarcasm** meant that rockets like the Saturn V were eligible for consideration? ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 30, 2019, 9:01pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/29 "2019-04-30T21:01:18Z")
> [@Machine\_Elf](#): > > but taking the OP as a whole, do you you honestly believe **Czarcasm** meant that rockets like the Saturn V were eligible for consideration? I couldn’t say. But **Czarcasm** only caveat was that “it can’t be the vehicle itself”. That makes sense to me: the question is about the payload of a vehicle, not the total mass. I claim that a Saturn V launch stack is not a single vehicle, and that it’s perfectly legitimate to view it as a 5M lb vehicle with a 1.5M lb payload. ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [April 30, 2019, 9:20pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/30 "2019-04-30T21:20:56Z")
> [@Dr.Strangelove](#): > > I couldn’t say. But **Czarcasm** only caveat was that “it can’t be the vehicle itself”. That makes sense to me: the question is about the payload of a vehicle, not the total mass. I claim that a Saturn V launch stack is not a single vehicle, and that it’s perfectly legitimate to view it as a 5M lb vehicle with a 1.5M lb payload. That’s funny-_I_ view the rockets as soon-to-be-jettisoned parts that are controlled from the cabin. Do they ever take off and/or land without being attached to the cabin? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 30, 2019, 9:55pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/31 "2019-04-30T21:55:06Z")
There have been unmanned Saturn V launches. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 30, 2019, 10:43pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/32 "2019-04-30T22:43:43Z")
> [@Czarcasm](#): > > That’s funny-_I_ view the rockets as soon-to-be-jettisoned parts that are controlled from the cabin. The first stage didn’t have any explicit control like that. It had a pre-programmed guidance computer that issued commands as a function of time or simple events such as the fuel level reaching a certain point. It was definitely not controlled by the cabin (and as **Chronos** notes, it couldn’t have been, since there were unmanned launches for Skylab). In some cases, such as solid booster motors, it’s not unreasonable to view them as just some auxiliary parts that get jettisoned eventually, like drop tanks on an aircraft. But on sequential staged rockets like the Saturn V, the stages are fully-fledged vehicles on their own. It’s more accurate to view these systems as a rocket with another rocket as the payload. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [May 1, 2019, 12:55pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/33 "2019-05-01T12:55:48Z")
> [@Dr.Strangelove](#): > > In some cases, such as solid booster motors, it’s not unreasonable to view them as just some auxiliary parts that get jettisoned eventually, like drop tanks on an aircraft. But on sequential staged rockets like the Saturn V, the stages are fully-fledged vehicles on their own. It’s more accurate to view these systems as a rocket with another rocket as the payload. Could the first stage have been flown by itself, without any payload whatsoever? If not, then I don’t think it’s reasonable to characterize it as a vehicle by itself, any more than one would characterize [the JATO bottles on the sides of Fat Albert](https://en.wikipedia.org/wiki/JATO#/media/File:C-130T_Hercules_Blue_Angels.jpg) as vehicles. I’ll also note that **Czarcasm** ’s OP stretched the definition of “aircraft” to include any vehicle that moves above the ground. That would mean my car is an aircraft, provided I drive off a cliff. Wikipedia defines “aircraft” as a machine that relies on the atmosphere for physical support. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [May 1, 2019, 10:12pm UTC](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999/34 "2019-05-01T22:12:26Z")
> [@Machine\_Elf](#): > > Could the first stage have been flown by itself, without any payload whatsoever? With minor modifications, sure. All of the major components are there: propellant, structure, engines, control systems, etc. The stages of a large liquid-fueled rocket are not at all analogous to JATO bottles or the like. There’s a direct comparison here to Skylab. Skylab flew on the Saturn V, but replaced the third stage. That’s where the instrument unit was located, and for Skylab it was kept in place since it was just a converted fuel tank anyway. But they could have moved it easily if they had to; it doesn’t change the overall picture. I hope that we can agree that Skylab counts as a payload, with the Saturn V as the vehicle, despite the fact that not all of the avionics were physically located in the rocket portion. If you accept that, then a first stage should count as an independent vehicle as well. > [@Machine\_Elf](#): > > I’ll also note that **Czarcasm** ’s OP stretched the definition of “aircraft” to include any vehicle that moves above the ground. That seems a step too far. I assume he meant _stable_ flight at the least. Airplanes use lift; zeppelins use buoyancy; rockets use thrust. A car falling off a cliff isn’t being kept at altitude by any forces. [Previous page](https://boards.straightdope.com/t/what-is-the-heaviest-single-object-ever-to-be-lifted-by-aircraft/832999.md?page=1)