Can you solve the airplane riddle? - Judd A. Schorr

I watch it 3 times😅

It’s interesting

Trying my hand at solving these. So plane one, plane two and plane three get one eight of the way around, then plane three gives a quarter of it's fuel and heads back. By the time it's back at the airport, plane one and two are a quarter of the way around the world. Plane two gives half of it's remaining fuel (a quarter of the full tank), and heads back, while plane three lifts off from the airport and heads towards it. They meet one eighths of the world away from the airport, where plane three refuels plane two and they head back to the airport to refuel.

By the time they get there the professor is half way across the world and has enough fuel to make it another quarter. Plane two meets it there and transfers half of it's remaining fuel (again a quarter), to plane one and they head back to the airport, while plane three lifts off to head towards them. They meet at one eighths of the world away from the airport. Planes one and two are now empty, and plane three is has three quarters of a full tank left. Plane three transfers one quarter of fuel to each plane and they head back to the airport.

Fukano’s plane travels around Mach 5.3, while the average plane goes around Mach 0.8. His plane can switch directions instantaneously, and can transfer fuel instantly as well. The only downside is the fuel consumption. His plane consumes 1,000 litres of fuel per minute, while the average plane consumes around 40 litres per minute. His plane is about 7 times faster than the average plane, but has 25 times the fuel consumption.

I thought you made them Japanese on purpose to let us know the assistants could crash!

Q : How long did Professor Fukano live ?

If a professor can design such a good plane, surely he can solve a riddle like this in seconds.

me when the earth isn’t spherical

I tried to solve this puzzle for more than an hour, trying to find the way to relay the fuel supply but found it to be never efficient, then I gave up and continue the video and when he tells that the planes can go the other way, my mind was like 🤯more than a hundred minutes spent in vain.

Step 1: confirm that you have green eyes
Step 2: ask the fuel tank if you can leave

The end song is the scariest one at night

One teeny problem: Human error. If any plane takes off a minute sooner or later than needed, the mission fails, as they simply run out of fuel and crash.

Also, travelling at 4 times the speed of sound and needing to switch directions at a very specific moment to be right next to another plane and transfer fuel sounds inhumanly difficult to pull off.

I DID THIS WITHOUT HELP SOMEONE GIVE ME A HIGH FIVE!

How did the Professor's in-flight meal spill? He only accelerated on takeoff and landing.

Imagine going that fast and just turning around instantly, goodbye spine

Wouldn't it also work if all 3 fly out 60 degrees/minutes, then Orokana transfers 60 kL of fuel to Fugori and uses the remaining 60 to return to base. At 90 degrees, Fugori is at 150 kL and Fukano is at 90, so Fugori can transfer 90 kL to fill up Fukano's tank and then head back with 60 kL left. If Orokana refuels and takes off right when she lands, then she will meet Fugori at 30 degrees right when his tank is dry, while she has 150 kL. As long as she transfers at least 30 kL, they should both have more than enough fuel to make it back to base right when Fukano is exactly halfway around the world with half his tank full, so they should both refuel and take off immediately to repeat the same process on the other side. At 60 degrees, Orokana transfers 60 kL to fill up Fugori's tank and uses the other 60 to return to base, where she immediately refuels and takes off. Fugori will have 150 kL left and meet up with Fukano at the 270 degree mark right as his tank runs dry. If Fugori transfers 90 kL to Fukano, then the professor will have enough fuel to finish the journey while Fugori will have enough fuel to make it to the 330 degree mark. If Orokana left right as she landed then she will be able to meet up with Fugori at the 330 degree mark with 150 kL of fuel, where she can transfer 30 kL to him and they both can make it back safely. Of course this only works if the planes can instantly land, refuel, and take off without wasting any time, but consider what else they can do this seems trivial for them.

Makes 3 super planes

Can't make better in flight meals

I spend a whole 10 minutes thinking of a solution not knowing they could refill their tank

Imagine the anxious feeling waiting for the plane to arrive when the fuel is just almost finish and finally seeing the plane and transfer fuels at the three-quarter mark

Flat earthers: this is wrong

Ok. 1º Longitude per minute is INSANE.

1º Longitude is about 51.54 miles.
This makes his plane go at 51.54 miles a minute.
Multiply that by 60 and we have OVER 3000 MPH. (4800 KPH)
FOR REFERENCE. COMMERCIAL FLIGHTS FLY AT 600 MPH (960 KPH).

While this speed isn't unheard of, the fact that it's a plane of his OWN DESIGN makes this absolutely INCREDIBLE.

how could a plane without retractable wheels be this fast?

"The planes can instantly reverse."
They're going to die anyways.
Circumference of earth = 40,075 km
1 degree longitude on the equator = 111.319 km
Speed = 6679 km/h = 1855.278 m/s (mach 5.409)

If the turnaround time was exactly 1 second, our pilots would experience about 3710.556 m/s^2 of acceleration, or 378.628163265 g where g = 9.81.

Sorry to be a downer, but you made a serious mistake. You forgotten that the Earth rotates during his flight time, either making the trip impossible if it rotates away from his way around or a lot easier if it rotates against the way he’s going around

For anyone wondering, to have a plane that could travel the 40,000km circumference the Earth in 6 hours, it would need to travel at almost 6700km/h, or nearly Mach 20. And its doing that while using 360kl of fuel and only a 180kl tank. That is damn impressive, when compared to a real-life standard 747, which carries almost 240kl.

So, its going over 20 times faster than a 747 (cruising speed of Mach 0.85), while only consuming 33% more fuel.

(BTW these numbers are all rounded for simplicity)

Bruh I got two solutions

First: He travels around the earth conserving nearly all his fuel using earth orbit

Second (a bit more complex than vid): Plane 1 gives travels to 60 degrees and transfers 60 fuel to plane 2

Plane 2 travels to 80 degree mark and transfers 80 fuel to main plane

Main plane now has full tank and travels to 260 degree mark

Plane one travels to -50 degree with plane 2 and transfers 50 fuel to plane 2

Plane 2 continues to -100 degree mark and transfers 100 fuel to main plane which arrives at same time at the 260 degree mark

Main plane travels straight home

Plane 2 travels to -50 with remaining fuel
Plane 1 travels to -50 and gives 50 fuel again to plane 2 right at arrival
And both plane travel straight home with no fuel to spare

I hope the commercially available version gets to hold more fuel than the ones he built. Enough fuel for a round the world trip, at least.

I have a VERY easy solution and don't understand why so complicated.
all planes travel and after 60 degrees both helpers transfer 60 kl and then go back. This is enough to let the professor reach the 300 degree mark. Then one plane is enough to go meet him at the 60 mark, give 60, and return. This is so easy. Am i wrong?

Such a waste of fuel in total...

😮🔒📝wow

spoilers for solution:




Prof, p1, p2 45 clockwise
p1 45 fuel -> prof
p1 45 fuel -> p2
prof & p2 45 clockwise, p1 45 anti-clockwise
p2 45 fuel -> prof
prof 90 clockwise, p2 90 anti-clockwise
prof 60 clockwise, p1 & p2 60 anticlockwise
p1 60 fuel -> p2
prof & p1 30 clockwise, p2 30 anticlockwise
p2 75 fuel -> prof
prof, p1, p2 30 clockwise
prof, p2 30 clockwise, p1 30 anticlockwise
p1 45 fuel -> p2
p1 45 fuel -> prof
prof, p1, p2 30 clockwise solved :)

if you believe yourself you can do it

If you run the math, Fukano's planes are actually quite massive. Each plane holds 180 kiloliters of fuel, and since 1 kiloliter = 1 m^3 and jet fuel is about 802.5 kg/m^3, each plane carries 802.5*180 = 144,450 kg in fuel alone (about 320,000 lbs). The SR-71 Blackbird weighed about 170,000 lbs full and 59,000 lbs empty, for a fuel mass of 111,000 lbs (just a third the size of Fukano's capacity). Assuming Fukano's aircraft has a similar structural coefficient to the SR-71, we can calculate that his plane weighs about 144,450*(170,000/111,000) = 221230 kg at takeoff (about 488,000 lbs or 244 tons).

This is roughly equivalent to the weight and size of the XB-70 Valkyrie or Concorde, but nearly 2x or 3x faster, respectively. Now imagine a vehicle that big turning on a dime!

I got most of the way through this using a spreadsheet and then got lazy at the last step. I was annoyed when I watched it and saw I was spot-on for the first moves. I could have spent another few minutes confirming the last flight was correct. Lazy me. I have a hideous cold in my defence. Haha. Nice puzzle. It kept me busy for a while. I don't understand why a maths puzzle is being called a riddle though.

I didn't know the refueling was possible.

I thought the professor was gonna fly at the opposite direction that the earth is rotating to technically fly more lol

I assume let professor Fukano and One of his assistant take off first! When professor runs out of fuel of 90 KL his assistant will assist him filling the 90 litres! And professor would still have 180 litres left! His assistant would die due to lack of his fuel cuz he donated the rest to him! Now, as the professor just travelled 270 degrees and is about to run of his remaining 90 KL of fuel! His second assistant would take off and reach in time to fuel him 90 KL again! Now professor can reach the equator where he started and he successfully completed his journey! Thanx for reading my solution!

If this strategy works, then it should also be able to work with only 2 planes.

The professor and his assistant travel next to each other for 1 quarter of the trip. The assistant gives the professor half their tank of fuel along the way.

The assistant goes back to the airport with just enough fuel to land. The professor will make the trip alone from the 1/4 to the 3/4 point.

The assistant refuels and then takes off as the professor gets to the halfway point.

The assistant meets up with the professor at the 3/4 point and will leave them both with just enough fuel to land.

Have a look at the Vulcan bombing raid on the Falkland Islands. Don’t know who worked out the math (Yanks) s for that!

What’s a “kiloliter”??? 😂

Me : Fugori and okana are kamikaze pilots
Narrator: they can't crash
Me :oh....................

Weld two planes together fly halfway around use the other plane to refill, fly the other half

That was fun!

unless I missed it, I got very confused since it was not stated how long it takes for the planes to refuel

All that speed and can turn 180 degrees on a dime = dead the moment you turn

There is more then enough fuel.

The theoretical minimum for 3 plans is 120 kilometers of fuel.

The real problem is without ways to freeze time the longest stretch must be as long or longer then time it takes for remaining planes in reserve to assist with the opposite direction. If planes only had 120 kiloliters then it would take infinite amount of planes. And if only had 3 planes the fuel wound need to be somewhere between 180 kiloliters and 120 kiloliters.

Wouldn’t the following solution be a lot easier.

Plane 1 and 2 take off west fly 1/4 of the earth. Plane 2 fills up plane 1 then flies back with half a tank.

Plane 3 takes off E moment before plane 2 gets back and meets plane 1 gets to the last quarter left giving just a hair over the quarter needed.

Then plane 3 returns with just under a quarter and plane 1 returns with just a hair left of fuel.

Basically
1/4
1/2
1/4
For plane 1

Another solution: Take the time to make 3 more planes THAT HOLD MORE FUEL!!!