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In The BFG, UK helicopters carry giants and leave them on an island:

enter image description here

Are helicopters capable of carrying this type of giants?

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    Heck, I would have just gone with the Mi-26 or the Mi-v12 Which, if you think about how much muscle weighs, I am willing to bet that those giants weigh just a tad over the max lift capacity of the sky crane and chinook. – NZKshatriya Nov 21 '16 at 3:33
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The Helicopters

There are basically two models of helicopter in this image.

Sikorsky CH-54 Tarhe and CH-47 Chinook

The Sikorsky CH-54 is capable of carrying a payload of 20,000 pounds i.e 9000 Kg while a CH-47 Chinook can carry up to 10,000 pounds i.e 4500 Kg.

The Giants

Now guessing from size of those giants they might vary from 3000 to 6000 kg.

Calculating weight of giants.

The height of each man-eating giant is around 50 feet (15 metres), according to Wikipedia. And from the their body mass I will consider them obese which means they have a BMI ranging from 25 to 30.

So BMI = Weight in KG / (Height in Metres)^2

Hence, Weight = BMI * (Height)^2

Assuming BMI = 25, Weight = 25 x 15 x 15 = 5625 Kg which is close to 6000 Kg.
Assuming BMI = 30, Weight = 30 x 15 x 15 = 6750 Kg which is close to 7000 Kg.

So the calculated weight ranges from 6000 to 7000 Kg. Right below the payload limit.

Conclusion

So yes, those helicopters can carry those giants.

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    BMI assumes body mass is proportional to height squared. We live in three dimensions. If giants were ten times our height (and width and depth), they'd be one thousand times our weight, ie. around 70,000 kg, much too heavy for the choppers. – Colonel Panic Nov 21 '16 at 11:13
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    The computation must be bogus. I am (under) 2m tall and weigh 100 kg; overweight but not fat. These giants are fat. One of them is as long as the sky crane, i.e. 27m. That makes him linearly 13 times as large as me, making him have 13*13*13* my mass, i.e. 100 * 13^3 = 100 * 1728 * 172800 kg, or 172 metric tons, about 17 times as much as the sky crane could lift. That fits with the usual size of water loads for fire fighting (much smaller). – Peter A. Schneider Nov 21 '16 at 11:35
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    @PeterA.Schneider: Definitely the CGI guys missed to keep proportion of helo's length and giants height. My computation is based on the Wiki info of their height to be around 50 feet. – Rahul Nov 21 '16 at 11:43
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    Ah, scaling strikes again. There are many problems with this. E.g., as you noted, the mass goes up with the cube of the scale, but the contact area of their feet with the ground only goes up with the square. Which means they put 8-15 times as much pressure on the ground as a human, and will probably sink in quite a bit. Also, the diameter of their bones will only go up with the square, but the weight they have to support goes up with the cube. Likewise, muscle strength is related to the diameter, i.e. goes up with the square, but the mass they have to move goes up with the cube. – Jörg W Mittag Nov 21 '16 at 13:04
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    BMI is wildly unsuited to this kind of calculation. The power term used (square) is a stonking simplification of reality (somewhere up around 2.7 for humans) that doesn't even work that well for people near the edges of the normal range of human heights yet alone so far beyond the range. Accordingly your numbers are a huge under-estimate of the "likely" weight of the giants. – Jack Aidley Nov 21 '16 at 13:35
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Transport helicopters are capable of carrying quite heavy and cumbersome loads externally as sling-load or underslung cargo, as long as the external load is properly attached and balanced and its weight doesn't exceed the max. permitted weight limit.

One of the helicopters in the picture is a Sikorsky CH-54 Tarhe (S-64 Skycrane) which is purposefully built to transport heavy, extreme loads. It can carry a jet fighter, or a house as underslung cargo, as pictured below:

enter image description here

enter image description here

And here is a Tarhe carrying a Chinook helicopter as underslung cargo:

enter image description here

So the way they carry the giants is realistic, this method of external load transport by helicopters is not uncommon in real life. If the giant's weight is within the max. premitted weight limits, then it is OK to transport them this way. But, after all, this is a movie, and in the world of movies everything is possible. The way the helicopters transport the giants in The BFG is certainly much more realistic than the way the jaegers are transported in Pacific Rim:

enter image description here

This will never happen in real life.

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    +1 for that last one - a bit of thought shows that the cables will tend to pull the helicopters together until they crash with each other, unless they expend considerable lift pushing away from the cable. – E.P. Nov 20 '16 at 18:05
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    Which they may do - helicptters are capable of having sideways thrust. THey would not be that vertical then, though (CGI failure) and it would be RIDICULOUSLY dangerous. I Can not imagine it even working without way too many accidents. In the above example you must coordinate 8 pilots perfectly for a no crash. Not realistic. – TomTom Nov 20 '16 at 18:43
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    Forget the logistics of synchronized flying with a common load - those jaegers are big enough to use trains as weapons. They must weigh eleventy bajillion pounds each. Only Yoda could lift a jaeger. – user9311 Nov 20 '16 at 19:28
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    @Tom maybe all the helicopter pilots drift tllt – Azor Ahai Nov 21 '16 at 5:28
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    Note that the objects in your examples are as big as the giants in the movie, but essentially hollow shells; the two aircraft are actually designed for minimum weight. The giants are essentially water tanks. Considering what i have seen in fire fighting the giants are way too large to be carried. – Peter A. Schneider Nov 21 '16 at 11:27
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I took easier approach than calculating mass. I took some info about similar sized animals. See info about Humpback Whale:

Adult males measure up to a maximum length of 15 – 18m and weight of 40 tonne. Adult females measure up to 15m and weigh from 22 to 35 tonne.

This is way over the limit as indicated by other posts.

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As I said in a comment, this is completely unrealistic (which is not surprising and not bad; it's a fantasy movie!).

As an approximation, the giants roughly look the size of the helicopters. For an estimate let's assume block shape of the helicopter's dimensions, 27x7x7m, or 1323 m3, meaning >1000 metric tons of mass, assuming the usual body density of about 1. That's roughly 100 times the payload of a sky crane. If we mis-estimated by a linear factor of 2 (which would be a little less than the size the giants have in the book, 50 ft) the weight would still be 1323/2^3 = 165 tons, 16 times the payload. (But actually the guy in the front looks significantly larger than the copter carrying him.)

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