The Plane That's 38% Nose — Transcript

Full transcript

1. 0:00This is the X59, NASA's latest Xplane and the  newest creation from Loheed Martin's Secretive
2. 0:05Skunk Works in Palmdale, California. The same  facility that produced the SR71, F-17 Nighthawk,
3. 0:12P-38, F-35, and F-22. This plane is designed  to do one thing. Make supersonic boom so quiet
4. 0:19that a supersonic transport could fly over  a city and barely disturb a mouse. With the
5. 0:25insane experience in a house at Skunkworks,  this plane became a Frankenstein monster.
6. 0:30Pieced together with parts and lessons from  F-16s, T38s, and even an old F-17 Nighthawk,
7. 0:36resulting in one of the most aerodynamically  interesting Xplanes in recent memory. But can
8. 0:41it really accomplish its mission? This is  the insane engineering of the X59 Quest.
9. 0:51The X59 is littered with interesting design  choices, but its key feature is right here.
10. 0:56This weird nose. From tip to nose wheel, it takes  up over half the plane. The pilot can't even see
11. 1:02out of the cockpit, and the center of gravity  is 3/4 down the plane where the wings curve deep
12. 1:07into the slim waisted fuse lo. All these sharp  twisting features are the result of a decade of
13. 1:12aerospace research on how to slice through the  air in an entirely new way. one that the X59
14. 1:18hopes will bring back supersonic flight. Because  ever since the Concord last flew, commercial air
15. 1:24travel has been subsonic and actually slowing down  yearbyear. Part of the reason for that, arguably
16. 1:30the main reason, is the lack of suitable routes  for supersonic passenger planes. The Conqueror
17. 1:35flew only a few select flights over the Atlantic  where it sonic boom couldn't bother anyone.
18. 1:41If we can quieten the booms, more routes would  open and drive money into the development of
19. 1:46supersonic passenger planes. The X59's unique  design choices are all in pursuit of this goal.
20. 1:52But let's start by explaining why it's impossible  to be both supersonic and silent. This is a
21. 1:58plane flying at 200 m/s, the speed of a regular  airliner. Like any object pushing through the air,
22. 2:05it generates pressure waves. They spread out in  all directions at the speed of sound. Most forces
23. 2:11transmit this way. You just don't notice the delay  between pushing a table and seeing it move because
24. 2:16the speed of sound in a solid is so high. Aircraft  just fly fast enough that it starts to matter. Now
25. 2:22watch as the plane speeds up. The pressure waves  traveling ahead of it don't get very far before
26. 2:26the plane catches up with them, causing them to  stack up and increase in pressure. And that's
27. 2:32how a shock wave is born. This causes a sudden  disruption of the air flowing over the plane
28. 2:37and sharply increases the drag it experiences. In  fact, the drag coefficient of a regular airliner
29. 2:43will double or triple at this air speed with a  corresponding increase in the forces acting on
30. 2:48its airframe too. These were enough to tear apart  the first aircraft traveling at these speeds. And
31. 2:53it was so difficult to get past them that pilots  coined the term sound barrier to describe it. And
32. 2:59it's even worse when not all parts of the plane go  supersonic at the same time. Here's the profile of
33. 3:05a regular wing. Air flowing over the leading  edge speeds up as it follows the curve. That
34. 3:10can push it past Mach 1, even if the rest of the  plane is slightly subsonic. Air transitioning from
35. 3:15subsonic to supersonic and back to subsonic again  doesn't follow the wing surface smoothly, causing
36. 3:21it to separate into turbulent flow that violently  shakes the wing. This is called MAC buffeting. The
37. 3:26aerodynamic center of the plane, the average point  where lift is generated, also shifts to the rear.
38. 3:32This effect, called Mac tuck, tends to pull the  rear up, causing the whole plane to pitch down.
39. 3:37If you're already in a dive, this deepens it,  something that affected the P38 and required
40. 3:43the addition of a dive flap to save pilots who  found themselves in high-speed dives. The X59,
41. 3:48of course, is built to handle this. It has delta  wings that can survive aerodynamic forces without
42. 3:54much structural support. They are highly swept,  effectively reducing the velocity of the air
43. 3:59perpendicular to the leading edge. In fact, the  sweep angle is deliberately chosen to be steep
44. 4:04enough that the entire wing can hide inside the  shock cone generated at the nose. Inside the cone,
45. 4:10the wings act as if they were in regular subsonic  air flow, avoiding the formation of shock waves
46. 4:15over their surfaces and becoming dramatically  more efficient. The wing profile is different,
47. 4:20too. Compared to a regular wing, it is very thin  and symmetrical from top to bottom. Air flowing
48. 4:26over the wing doesn't accelerate as much, so  it's harder to form shock waves and separate
49. 4:30into turbulent flow. The shock waves above and  below the wing are balanced, too, reducing mock
50. 4:35buffeting. The downside to this profile is that it  doesn't produce lift unless it enters the air at
51. 4:41an angle, unlike a regular wing. But you can see  that the X59's wings are installed with a natural
52. 4:47angle already. To maintain control, the X59 uses  all moving stabilators instead of elevants in
53. 4:53the tail. If the whole control surface tilts into  the airflow, there's nothing behind the turbulent
54. 4:58wake. So control is retained at supersonic  speeds. It adds a supersonic trim. That is,
55. 5:04it tilts the nose up to counter the rearward shift  in its center of lift caused by Mac Tuck. Normally
56. 5:10doing so adds drag, but the canards in the nose  are angled in a way to passively move the center
57. 5:15of lift back to the front. So, the amount of  trim the X59 needs is cleverly reduced. Now,
58. 5:21the X59 accelerates past Mach 1. It is going  supersonic, outrunning its own pressure waves as
59. 5:28they get dragged behind it in a narrowing shock  cone. The X59's design speed is Mach 1.4, which
60. 5:34is 413 m/s in the cold air at 15 km altitude. At  this speed, its pressure waves are pressed into
61. 5:41a 45° cone, an unavoidable aspect of breaking  the sound barrier that makes it impossible to
62. 5:47fly silently. If you were standing on the ground  with one of these planes speeding overhead, you'd
63. 5:52see it move past silently. Then, after delay,  you'd hear a distinct bang bang. This double
64. 5:58boom sweeps over the landscape, and it can be  strong enough to shake buildings or break windows.
65. 6:03The reason it's so powerful is because the shock  waves from a supersonic aircraft merge as they
66. 6:09spread away from the aircraft, adding up their  energy until there's two peaks in an N-shaped
67. 6:14wave. This Nwave weakens as it travels down, but  enough energy is gathered in each peak to produce
68. 6:20a loud double boom at ground level. Quest goal is  not to eliminate supersonic booms, but to alter
69. 6:26them in a way that they are no longer disruptive  to the people on the ground. There's two parts
70. 6:31to it. weakening the shock waves so they become  quieter and then shaping them so they don't become
71. 6:37a powerful n-wave. The first part relies heavily  on the Witcom area rule discovered by Richard
72. 6:43Wickcom in 1952 while experimenting with wind  tunnels. It basically states that abrupt changes
73. 6:49in the cross-sectional area of a plane from nose  to tail are what create the strongest shock waves.
74. 6:55A fuselage like a straight cylinder would have  a constant cross-section until the air flow
75. 6:59reaches the wings which suddenly adds a lot of  cross-sectional area. In the earliest supersonic
76. 7:05planes, this was the source of a very strong  shock wave which resulted in immense drag. If
77. 7:10instead the fuse latch narrowed at the point  where the wings were attached, the change in
78. 7:14cross-sectional area would be less abrupt and  the shock waves would be weakened. Planes which
79. 7:19follow the Wickcom area rule typically have a coke  bottle fuselage with a narrow waist and smooth
80. 7:25curves. Modern aircraft analyze every change in  cross-sectional area to follow the Wickcom rule
81. 7:31from the cockpit bubble to the rudder placement.  But the X59 applies the area rule differently. It
82. 7:37is trying to generate the weakest shock waves by  having the smoothest transitions possible between
83. 7:42its thick and thin sections. That's why the nose  is so long and why the cockpit blends seamlessly
84. 7:47with the fuselage. And because of this, the pilot  has to rely entirely on the cameras and screens of
85. 7:53its external vision system to fly the plane.  At the point where the wings are the widest,
86. 7:58the fuselage is also the narrowest.  The engine looks like it sticks out,
87. 8:02but the airflow sees it as a hollow tube rather  than an obstacle, so it doesn't actually change
88. 8:07the cross-sectional area as much as you would  expect. In the rear, the tail is short with
89. 8:12the rudder bridging the gap between the wings  and the stabilators. Thanks to these features,
90. 8:17the only strong shock waves that are generated are  near the canards and the engine intake. The intake
91. 8:22has a special bump called a divertless supersonic  inlet that solves two problems with high-speed
92. 8:27flight. You can see these on the most advanced  fighter jet, the F-35. As air travels along the
93. 8:33length of the body, air begins to form a layer of  slowmoving turbulent air called a boundary layer.
94. 8:39If this air is allowed to enter the engine, it  not only lowers performance, it can also damage
95. 8:44the engine. As the turbine rotates, it will pass  through the slow boundary air on one side and then
96. 8:50the fast free stream air on the other. This means  the force on the turbine blade changes for each
97. 8:56and every rotation, causing cyclical bending, a  recipe for fatigue failure. Planes like the F-16
98. 9:03feature a boundary layer diverter that separates  the inlet from the fuselage with a small gap,
99. 9:09but this design increases drag. Later variants of  the F-16 tested the DSI, a divertless supersonic
100. 9:16inlet, essentially a large bump that creates a  region of compression that pushes the boundary
101. 9:21layer away from the inlet while lowering drag. The  test flight demonstrated it could meet performance
102. 9:27requirements, ushering in its introduction to the  F-35. The final product reduces weight by 30% and
103. 9:34lowers production and maintenance costs. The X59  takes it to the next level by moving it onto its
104. 9:40back, so the shock wave it produces is directed  up and away from the ground. The next step in
105. 9:46Quest design is to shape the sonic boom. If the  main wings did all of the lifting, there'd be a
106. 9:51single strong shock wave centered on them. With  the canards, large stabils, and little fins on the
107. 9:57rudder, the sources of lift are distributed along  the plane's length, resulting in multiple smaller
108. 10:02shock waves precisely spaced out from each other.  The X59's unconventional layout helps it move all
109. 10:08of these shock waves far enough apart that they  don't merge as they travel down to the ground.
110. 10:14Instead of adding up into a single N-wave, they  stay separate and weak all the way to the ground
111. 10:19where they're heard as a longer, softer thump  rather than a short boom. The objective here is to
112. 10:25reduce the volume of a sonic boom down to 75 dB.  That's like a door slamming shut across the street
113. 10:32or a small truck passing you on the highway.  To get to this point, the X59 was put through
114. 10:37a rigorous regime of computer simulations and wind  tunnel tests. Every bump and curve was mapped out
115. 10:43and its effects on the air flow calculated by  the advanced supercomputing division at the AS
116. 10:49research center. Scale models of the X59 were  placed into wind tunnels at NASA's Langley,
117. 10:54Loheed Skunk Works, and even Jax's test  facility in Tokyo. All of this makes the X59
118. 11:00a unique design, but it's not the first plane  to try to shape its own sonic booms. The most
119. 11:06recent is this NASA F-15B that collaborated with  Gulfream Aerospace on the quiet spike project. A
120. 11:13multi-stage 7.3 m extendable spike was installed  on its nose, adding 38% to the jet's length that
121. 11:20helped split the shock cone at the front of the  plane into three smaller shock waves. Before that,
122. 11:25the same F-15B tail number 836 was used to trial  an ugly duckling F5E fitted with the much longer
123. 11:32nose and modified fuselage to measure whether it  could reduce the intensity of its sonic boom in
124. 11:38flight. It did so by one/3. The X59 program is  the most serious attempt at designing a plane
125. 11:44purpose-built for reducing sonic booms. Loheed  Martin Skunk Works got a quarter of a billion
126. 11:49dollar contract to build it. Parts from existing  planes were used wherever possible to save
127. 11:54time and reduce costs, which is why it got the  landing gear of a Falcon, the engine of a Hornet,
128. 12:00the cockpit canopy of a T38 Talon, the control  stick of a Nighthawk, and even components from a
129. 12:05U2 spy plane. After 5 years in the workshop, the  X59 rolled out in 2023. The X59 was unveiled to
130. 12:13the public on the 12th of January 2024, but its  first cautious flight only happened on October
131. 12:192025. In 2026, it is still being put through its  paces. It reached an altitude of 6 km in April,
132. 12:26then went supersonic for the first time in June  2026. A week later, it reached its design speed
133. 12:33of Mach 1.4 at an altitude of 15 km. The next  step is to fly over Edward's Air Force Base while
134. 12:40surrounded by sensors and microphones, both on the  ground and flying alongside it at all altitudes to
135. 12:46demonstrate that the low boom concept will work  in the real world. Wind tunnel testing doesn't
136. 12:51say what weather, winds, clouds, and terrain due  to the impact of sonic booms on the ground. So,
137. 12:57the data can only be gathered live. Then the  big test. The X59 will be flown over several
138. 13:03US cities to measure how residents will react to  its sonic booms. This community response testing
139. 13:09is the most important step in changing flight  regulations from a straightup supersonic ban to
140. 13:14a 5.3 Pascal ground pressure restriction. If it  succeeds, the door may open to a new generation
141. 13:20of supersonic passenger flight. But a quieter  supersonic boom doesn't solve all the problems.
142. 13:26Technology may have progressed, but it's arguably  more difficult economically to pull off today,
143. 13:31mostly on fuel costs. Supersonic jets need  smaller fuselages to cut down on drag and
144. 13:37thus can spread the cost of fuel across as many  passengers. With fuel costs higher than ever,
145. 13:42the next big challenge is getting fuel demands  lower. But that's no easy task. The engineers of
146. 13:47the X59 chose to use a reliable off-the-shelf  military engine, the General Electric F414,
147. 13:54the same engine the Super Hornet uses. This was  primarily a cost of development choice, but these
148. 14:00engines will just not cut it for a commercial  application. The Concord was excellent in Super
149. 14:06Cruise. Its four Olympus engines turned out to  be the most thermodynamically efficient motors
150. 14:10of their time, thanks to a complex arrangement of  intake ramps that could compress the incoming air,
151. 14:16slowing it down while recovering its kinetic  energy as pressure rather than wasting it. That
152. 14:22way, it could super cruise at Mach 2, but  getting up to super cruise required costly
153. 14:27afterurners. The Soviets actually beat the  Concord into service with the Tupalev Tu44.
154. 14:33It was heavier, faster with 42% more powerful  engines and canards to help it lift off. But
155. 14:39its tragically unlucky career was terminated after  3 years. The X59 inherits features from both. Its
156. 14:46delta wings are actually double deltas similar to  the Concord with the inner portion at 76° and the
157. 14:52outer portion at 68.6°. Its canards also help by  generating vortices that spill over onto the main
158. 14:59wing at low speed. The next piece of the puzzle  is creating an engine that can run efficiently at
159. 15:04both subsonic and supersonic speeds. Astromechanic  is designing and testing hybrid engines with
160. 15:10an electric fan mode at low speed, an efficient  turbo fan mode for transonic to supersonic flight,
161. 15:16and a ramjet mode to keep it pushing up to Mach  3. A design this advanced is only made possible
162. 15:21by recent progress in high powertoweight  ratio electric motors, dense batteries,
163. 15:26and heatresistant ceramic turbine blades. And just  a little side note, my other company, Throttle,
164. 15:32actually created these animations for Astrome  Mechanica. If you run an engineering company
165. 15:37and need help making animations, we can help you  out. With engines like these, a supersonic plane
166. 15:42could enter a virtuous cycle of needing less fuel  to make a trip, which means smaller wings to take
167. 15:47off, which leads to less drag and smaller engines,  which in turn reduce the fuel needed further,
168. 15:52which would also potentially open up options  for longer range trans-pacific routes,
169. 15:57which could prove extremely valuable. But  it's not a done deal. Private companies have
170. 16:02attempted to bring back supersonic flight since  the Concord ended in 2003. The Aryan Corporation
171. 16:08spent between500 million and a billion dollars on  its AS2 design, a sort of supersonic business jet,
172. 16:14but failed after declaring the effort would take  closer to $10 billion. Exos, Virgin Galactic,
173. 16:20and Spike Aerospace have all tried and failed.  Boom Aerospace is the current contender. They plan
174. 16:26to deliver an 80 seat supersonic jet called the  Overture, which would super cruise at Mach 1.7.
175. 16:32It has raised about $600 million to do it and  has been working on it for the past decade when
176. 16:38it isn't busy designing gas turbines to power AI  data centers. That is instead of a painstakingly
177. 16:44designed airframe with a shaped sonic boom  like the X59, they're relying on Mac cutoff,
178. 16:49a phenomenon where sonic booms don't reach the  ground if they start out between Mach 1.1 and Mach
179. 16:541.3 at around 10 km altitude. A phenomenon they  have tested once and claimed success. Simply put,
180. 17:02sonic booms are sound waves that refract when  traveling through air of different densities,
181. 17:06and they can bend enough to make a U-turn in the  air and never reach the ground under specific
182. 17:12weather conditions. This means Boom Aerospace  would be constantly adjusting its speed, altitude,
183. 17:17and flight path while navigating through  the atmosphere, looking for those perfect
184. 17:22conditions. There's still no guarantee that Boom  Aerospace or some other company will succeed.
185. 17:28Supersonic jets will always be more expensive  than subsonic airliners just because they
186. 17:33take more fuel and make more sacrifices to  carry each passenger. Rising fuel costs and
187. 17:38businesses relying on video calls rather than  physical meetings in other countries are also
188. 17:42making them less likely. But there are a lot  of people who will pay thousands of dollars to
189. 17:47save themselves a few hours. And with 5,500  new millionaires being printed every single
190. 17:53day around the world, finding a market for these  faster planes might not be so difficult. Just to
191. 18:00demonstrate how far technology has come since  the Concord made its first flight in 1969,
192. 18:05this was how big state-of-the-art calculators  were at the time. This is the AL-1000 Commodore,
193. 18:11manufactured by Casio in Japan in 1968.  It's a beautiful piece of computer history.
194. 18:17It has just 448 bits of memory from its core  memory array which stores data on tiny iron
195. 18:23rings. And these high voltage Nixie tubes demanded  a fairly complex power supply. I bought this as
196. 18:29part of a Nebula series where I put cool objects  like the Nokia 3310 and the first generation iPod
197. 18:35into a CT scanner and then used the Volutric  models to make messmerizing animations. Well,
198. 18:41this calculator is both too big and too heavy  to fit in the CT scanners we are using. So,
199. 18:48uh I I messed up there. But it did kickstart  a new obsession for me. Uh the history of old
200. 18:54calculators. So, instead, the first episode  is about the Curta mechanical calculator,
201. 18:59which is an absolutely fascinating little portable  calculator that uses gears and rotating levers for
202. 19:05calculations. You can watch that episode when it  releases on Nebula next month. With the help of
203. 19:10Nebula, we hired a new animator with a background  in electronic engineering to take the animation
204. 19:15technique we developed to make one of these  episodes a month. Next month, we'll be going
205. 19:20further down this new calculator collecting hobby  with the Sharp E8, which launched just 4 years
206. 19:25after this gigantic thing and benefited from  the new arms race in microchip development. So,
207. 19:31subscribe to Nebula if you want to watch me obsess  over old calculators for the next few months.
208. 19:37A monthly subscription to Nebula is usually $6.  But with my link or the QR code on screen right
209. 19:42now, you can get an entire year's membership  for just $30. Or if you're sick of signing up
210. 19:48to new subscription services like I am, we've  created a lifetime membership if you'd rather
211. 19:52just pay it and forget it. With YouTube policies  changing more and more in favor of slop scrolling,
212. 19:58every subscriber over Nebula counts where we can  focus on the things that really get us excited.