WEBVTT - TechStuff Classic: How Helicopters Work 0:00:04.120 --> 0:00:07.160 Get in touch with technology with tech Stuff from how 0:00:07.200 --> 0:00:14.680 Stuff Works dot Com. Hey there, and welcome to tech Stuff. 0:00:14.720 --> 0:00:17.959 I'm your host, Jonathan Strickland. I'm an executive producer with 0:00:18.000 --> 0:00:20.279 How Stuff Works in I heart radio and I love 0:00:20.440 --> 0:00:24.000 all things tech. And it's time for another classic episode, 0:00:24.440 --> 0:00:28.600 and this one, which originally published on February twenty seven, 0:00:28.840 --> 0:00:32.720 two thousand twelve, Chris Palette and I talk about how 0:00:32.840 --> 0:00:36.920 helicopters work. As I recall, the Marines say that the 0:00:36.960 --> 0:00:41.760 helicopters fly by beating the air into submission. So, without 0:00:41.880 --> 0:00:45.760 further ado, let's get to chop off. We're gonna talk 0:00:45.760 --> 0:00:49.320 about helicopters today. Yes, and it's rising that we haven't 0:00:49.320 --> 0:00:51.520 talked about it before. Yeah. Well, when you start looking 0:00:51.520 --> 0:00:55.840 into what is involved in making a helicopter work, I 0:00:55.880 --> 0:00:58.760 can see exactly why we haven't done it before. Well, 0:00:58.800 --> 0:01:01.120 you know the helicopter business US have it have its 0:01:01.200 --> 0:01:03.480 ups and down. Yeah. Nice, I like how you did that. 0:01:03.840 --> 0:01:07.880 Um yeah, So so let's talk about helicopters. So, I'm 0:01:07.920 --> 0:01:10.600 sure all of you are familiar with the concept of 0:01:10.640 --> 0:01:14.800 a helicopter, but when did these things? How did how 0:01:14.800 --> 0:01:16.680 did we come up with this idea? When did this 0:01:16.800 --> 0:01:22.080 originally spring to mind. Okay, well, uh, you know, it 0:01:22.840 --> 0:01:25.280 is something that has been on my mind since I 0:01:25.319 --> 0:01:28.280 was a kid. I've always loved helicopters. So the other 0:01:28.400 --> 0:01:31.360 day Jonathan sent me a video that I couldn't watch 0:01:31.400 --> 0:01:35.000 because my current bandwidth was too low on my Internet connection, 0:01:35.040 --> 0:01:37.440 and it took me two days to actually watch it. 0:01:37.480 --> 0:01:42.360 But it was a video of some very tiny quadricopters. Yeah, 0:01:42.400 --> 0:01:45.800 they were called nano quadricopters in the video itself, although 0:01:45.840 --> 0:01:49.280 that is a misnomer since nano typically means one billion. 0:01:50.080 --> 0:01:53.280 And they were not that small. No, they fit on 0:01:53.320 --> 0:01:55.240 the palm of someone's hand. Yeah, they're about the size 0:01:55.240 --> 0:01:57.680 of the palm of your hand. And uh, I was 0:01:57.720 --> 0:02:01.880 thinking about how, uh, how unusual the quadracopter is because 0:02:01.880 --> 0:02:06.360 it doesn't have a tail roader like a traditional helicopter does. Um. Yeah, 0:02:06.440 --> 0:02:10.000 they're very very maneuverable. Um and uh and I thought, 0:02:10.000 --> 0:02:12.559 you know, hey, Jonathan, why don't we talk about helicopters 0:02:12.560 --> 0:02:14.840 because we never really talked about them before. So, right, 0:02:14.919 --> 0:02:17.080 so that's how I came to mind. Yeah, that's how 0:02:17.080 --> 0:02:19.280 I came to mind. Now, how how the idea of 0:02:19.280 --> 0:02:22.760 a helicopter actually came to mind for human beings in general. 0:02:23.480 --> 0:02:27.640 That dates back pretty far in human history. And it 0:02:27.680 --> 0:02:31.080 all begins with a toy. Yeah, you know, and I 0:02:31.080 --> 0:02:34.840 think just about everybody who's gone to their school fair 0:02:34.919 --> 0:02:36.720 or whatever is one one of these little you know, 0:02:37.160 --> 0:02:40.320 seventy two cent uh stick with a propeller on it 0:02:40.480 --> 0:02:42.000 and you spin in the palm of your hand and 0:02:42.080 --> 0:02:45.760 let go and it'll fly up and then crash down 0:02:45.760 --> 0:02:48.800 to the earth. But they weren't always made from plastic, no, No, 0:02:48.960 --> 0:02:53.800 they were. The Chinese had a little top that they 0:02:53.919 --> 0:02:57.919 used where the top was had feathers on it, Yes, 0:02:58.000 --> 0:02:59.560 and it did the same sort of thing. You would 0:02:59.680 --> 0:03:02.040 put a put the stick between your hands, the feathers 0:03:02.040 --> 0:03:04.079 will be at the top. You spin the stick very quickly. 0:03:04.440 --> 0:03:06.840 The feathers would spin and it would create some lift 0:03:07.000 --> 0:03:08.680 and the sick would fly up in the air and 0:03:08.680 --> 0:03:12.480 then come back down. Pretty simple, yep. And as it 0:03:12.520 --> 0:03:16.000 turns out to the concept is is pretty simple. Basically, 0:03:16.040 --> 0:03:20.239 you're you're creating an air foil. Yes, Um that instead 0:03:20.240 --> 0:03:24.399 of like an airplane wing where you're going forward, Um, 0:03:24.600 --> 0:03:27.720 it is going straight up simply because um, the the 0:03:27.760 --> 0:03:30.440 air that that moves over the air foil, it creates 0:03:30.480 --> 0:03:33.720 lift is taking it straight up instead of forward. Yes, 0:03:34.080 --> 0:03:37.160 So I guess to to really kind of discuss this, 0:03:37.280 --> 0:03:39.840 we should probably talk about a little bit about the 0:03:39.880 --> 0:03:43.480 parts of a helicopter, so that way we can explain 0:03:44.200 --> 0:03:47.680 what these these parts actually do and how they achieve flight. 0:03:48.240 --> 0:03:52.920 So the blades that we talk about, that's a rotor, right, 0:03:53.160 --> 0:03:56.800 So the rotors are affixed to a rotor mast. That's 0:03:56.840 --> 0:04:00.160 the part that actually creates the the turning motion, and 0:04:00.520 --> 0:04:02.840 that makes the blades go round in a circle. And 0:04:02.880 --> 0:04:06.840 the blades themselves are angled and they can that angle 0:04:06.880 --> 0:04:10.840 can change depending upon a control um. There are different 0:04:10.840 --> 0:04:14.480 control rods that can change the the um the attitude 0:04:15.040 --> 0:04:18.320 of those blades. So you have, uh, two of them. 0:04:18.320 --> 0:04:22.800 Actually there's the cyclic controller which can control them individually. Yes, 0:04:22.880 --> 0:04:25.520 that's also known as the stick, right, Yeah, that's the 0:04:25.760 --> 0:04:27.880 that's the stick. And then there's a was it the 0:04:27.920 --> 0:04:31.400 collective one, right, yes, the collective pitch lever. What that 0:04:31.440 --> 0:04:34.919 does is it actually changes the attitude of all of 0:04:34.960 --> 0:04:38.640 the rotors, the main rotors at the same time. Um. 0:04:38.680 --> 0:04:41.919 And that both of those are important for various maneuvers 0:04:41.920 --> 0:04:43.920 with the helicopter. But we'll get into that in a second. 0:04:44.240 --> 0:04:48.279 There's also with the rotors, there's a a stabilizer. Because 0:04:48.440 --> 0:04:51.719 you've got these long air foils that are extending out 0:04:51.760 --> 0:04:55.400 from a shaft and they're turning around and around. There's 0:04:55.400 --> 0:04:57.320 a chance that they're gonna start, you know, flopping around 0:04:57.360 --> 0:05:00.120 a little bit, causing some issues, you know, of the 0:05:00.160 --> 0:05:03.480 stabilizer is there to help add some rigidity there so 0:05:03.560 --> 0:05:07.919 that these blades will will maintain the right shape so 0:05:07.960 --> 0:05:10.600 that you can fly. It's kind of funny too, because 0:05:10.640 --> 0:05:13.000 apparently it was just one of those things that someone 0:05:13.040 --> 0:05:17.960 added to the helicopter um uh And as as it 0:05:17.960 --> 0:05:20.800 turns out, it it made a major improvement in the 0:05:20.839 --> 0:05:24.839 stability and and flyability of helicopters. Yeah, the early helicopters 0:05:24.880 --> 0:05:27.320 when they were flying, it was a pretty bumpy ride 0:05:28.120 --> 0:05:30.680 and it was definitely a challenge for a pilot to 0:05:30.839 --> 0:05:35.000 maintain control because it just you know, without that stabilizer, 0:05:35.080 --> 0:05:38.480 it just like you were saying, it just wasn't as fliable. 0:05:38.880 --> 0:05:42.480 So it was definitely a good addition to the parts 0:05:42.480 --> 0:05:46.920 of a helicopter. There's a there's a there are two 0:05:46.960 --> 0:05:51.599 plates they are on the rotor mast, all right, that 0:05:52.120 --> 0:05:55.560 that also are a big part of the helicopter. It's 0:05:55.560 --> 0:05:59.719 called the upper swash plate and the lower swash plate. 0:06:00.120 --> 0:06:03.000 And despite what you might think, they are not joined 0:06:03.040 --> 0:06:08.480 by a swash buckle. Instead, if you imagine that, they 0:06:08.520 --> 0:06:12.960 imagine two plates to two round plates, right, and they're 0:06:12.960 --> 0:06:16.040 both they both have the the shaft of the motor 0:06:16.320 --> 0:06:19.839 of the rotor rather goes straight through these two plates. 0:06:20.120 --> 0:06:23.919 The lower plate is stationary, it does not turn. On 0:06:24.080 --> 0:06:27.279 top of the lower plate are ball bearings, yes, And 0:06:27.320 --> 0:06:29.680 then on top of the ball bearings is the upper swashplate, 0:06:29.760 --> 0:06:32.520 which does turn. The ball bearings are what allow it 0:06:32.600 --> 0:06:36.440 to turn over. The lower swashplate, now the swashplate. The 0:06:36.440 --> 0:06:39.000 reason that's important is remember when I was talking about 0:06:39.040 --> 0:06:43.200 the collective the collective control that changes the attitude of 0:06:43.240 --> 0:06:46.320 all the blades at the same time that what that 0:06:46.360 --> 0:06:50.320 actually does is it allows that plate to tilt either 0:06:50.400 --> 0:06:53.560 forward or backward, or however you need it to, so 0:06:53.600 --> 0:06:57.040 that you can make the helicopter veer in the direction 0:06:57.320 --> 0:07:00.760 you want it to go. Because really, until this point, 0:07:01.160 --> 0:07:03.120 what we were doing was going up and down. We 0:07:03.120 --> 0:07:06.640 weren't going left or right, or over that way or 0:07:06.960 --> 0:07:10.120 back this way. Because if you try, if you have 0:07:10.160 --> 0:07:11.960 one of those toys that we were talking about before. 0:07:12.040 --> 0:07:15.160 With the blade on the stick, you point it straight 0:07:15.240 --> 0:07:17.280 up and it goes straight up, and then it'll drift 0:07:17.320 --> 0:07:18.800 off a little bit to the side, but you don't 0:07:18.800 --> 0:07:21.560 really control that. If you pointed it, you know at 0:07:21.600 --> 0:07:24.880 your friend, it's going to go in his or her direction. 0:07:25.200 --> 0:07:28.840 And that's what the swash plates allow the pilot of 0:07:28.880 --> 0:07:31.160 the helicopter to do it. It helps filp the blades 0:07:31.200 --> 0:07:34.400 and and the helicopter starts flying in that direction. Yes, 0:07:34.480 --> 0:07:37.680 because it adds it adds a second element. Right, you 0:07:37.720 --> 0:07:40.160 first have the first element you have is lift, Right, 0:07:40.200 --> 0:07:43.080 The second element you would have is thrust. Yes, so 0:07:43.120 --> 0:07:45.880 when you start to change the attitude of the blades, 0:07:46.120 --> 0:07:48.160 you have both lift and thrust. Now, there is a 0:07:48.200 --> 0:07:51.320 point where if you were to tilt that beyond a 0:07:51.400 --> 0:07:54.960 certain threshold, you would no longer have enough lift to 0:07:56.200 --> 0:07:58.880 counteract the weight of the helicopter itself, and it would 0:07:58.880 --> 0:08:01.840 start to lose altitude. They might be moving forward, but 0:08:01.880 --> 0:08:04.400 it's going to be going lower and lower until you 0:08:05.120 --> 0:08:08.200 correct that. And that's one of the reasons why UH 0:08:08.560 --> 0:08:11.560 piloting a helicopter is so challenging. In fact, when we 0:08:11.600 --> 0:08:14.040 get into the different controls. You'll find out you're using 0:08:14.120 --> 0:08:16.520 both your legs and both your arms to try and 0:08:17.040 --> 0:08:20.440 maneuver a helicopter, and so it takes a lot of concentration. Yeah. Yeah, 0:08:20.560 --> 0:08:22.520 it's also why you don't see a lot of people 0:08:22.600 --> 0:08:27.240 flying helicopters and loop to loops. Yeah, that's let's their 0:08:27.240 --> 0:08:30.800 air wolf that right. Yeah, but then no, that is 0:08:30.800 --> 0:08:33.280 true because once you get beyond that certain threshold, you 0:08:33.320 --> 0:08:35.520 no longer have the lift necessary to keep you in 0:08:35.559 --> 0:08:38.760 the air. Uh. And these blades are connected to that 0:08:38.840 --> 0:08:42.400 rotor mast through blade grips, that's the technical term for 0:08:42.520 --> 0:08:45.440 where the blades fit into this rotor mast. And on 0:08:45.480 --> 0:08:47.520 the very top of the rotor mast, you have something 0:08:47.520 --> 0:08:52.160 that's that's got an interesting name. Yes, the Jesus nut. Yes, 0:08:52.480 --> 0:08:54.560 it really is called that. It's called the Jesus nut. 0:08:54.640 --> 0:08:58.000 And uh, there are various furies as to why it's 0:08:58.000 --> 0:08:59.920 called that, and I don't know what any of I 0:09:00.000 --> 0:09:02.040 don't know the truth of any of them. Yes, the 0:09:02.040 --> 0:09:04.040 one that we have an article on the site. Yes, 0:09:04.160 --> 0:09:06.240 it's a it's a really good article too, with lots 0:09:06.240 --> 0:09:09.520 of really helpful illustrations. So if you are interested in 0:09:09.520 --> 0:09:11.640 helicopters and you really want to get a look at 0:09:11.679 --> 0:09:14.679 what these different parts look like. I highly recommend you 0:09:14.760 --> 0:09:16.920 check it out because it's it's one of the more 0:09:16.960 --> 0:09:20.240 exhaustive articles on the site. I would say, yeah, I would, 0:09:20.240 --> 0:09:24.080 I would agree with that and very very illustrative what 0:09:24.200 --> 0:09:28.800 you're doing here when you're flying a helicopter. Um. So, yeah, 0:09:29.040 --> 0:09:32.239 we were talking about the tail rotor just a moment ago. Yes, Um, 0:09:32.480 --> 0:09:35.760 very important in the in the design of a helicopter. 0:09:35.840 --> 0:09:38.679 So here's another thing about helicopters. You've got this blade 0:09:38.679 --> 0:09:40.800 turning around and around, this creating lift, and when the 0:09:40.840 --> 0:09:43.640 lift gets strong enough to counteract the weight of the 0:09:43.679 --> 0:09:46.360 helicopter is going to rise in the air. Without a 0:09:46.400 --> 0:09:49.640 tail rotor. Yeah, if you've ever wondered why that's there. Yeah, 0:09:49.679 --> 0:09:52.679 without a tail rotor, which is that little, that little 0:09:52.800 --> 0:09:55.679 smaller propeller that's on the end of the tail of 0:09:55.720 --> 0:09:59.440 a helicopter. Without it, the body of the helicopter itself 0:09:59.440 --> 0:10:03.120 would start spin in a direction opposite that of the rotors. 0:10:03.559 --> 0:10:06.840 So if the rotors are spinning in a clockwise direction, 0:10:06.920 --> 0:10:08.920 then the helicopter will start to spin in a wider 0:10:08.960 --> 0:10:12.160 Shian's direction. You just wanted to use, Yes, I did 0:10:12.240 --> 0:10:15.120 so badly counterclockwise. For those of you who do not 0:10:15.240 --> 0:10:19.480 speak archaic English, hey, where are my Shakespeare Homi's at 0:10:19.920 --> 0:10:23.640 So anyway, Yes, the the helicopter would spin without any 0:10:23.640 --> 0:10:26.880 other other force to counteract this, the helicopter would start 0:10:26.920 --> 0:10:29.320 to spin in the opposite direction, which would probably be 0:10:29.400 --> 0:10:34.559 an unpleasant experience for anyone inside that helicopter. Yes, yeah, 0:10:34.679 --> 0:10:37.120 so the rotor What that does is it helps to 0:10:37.160 --> 0:10:40.720 create thrust to counteract the spinning motion so that the 0:10:40.760 --> 0:10:44.839 helicopter stays stationary. And by controlling the speed of that rotor, 0:10:45.240 --> 0:10:48.480 you can actually turn the helicopter to the left or 0:10:48.480 --> 0:10:51.400 to the right, not banking it. But actually if you're 0:10:51.400 --> 0:10:54.080 in if you're hovering in place, you can change the 0:10:54.120 --> 0:10:58.120 speed that that rotor turns and then turn your helicopter 0:10:58.160 --> 0:11:00.679 so it's facing an opposite direction, so if it started 0:11:00.679 --> 0:11:03.160 facing north, you can maybe face west. That kind of thing. 0:11:04.240 --> 0:11:07.760 And of course, uh, for for this, we have a 0:11:07.760 --> 0:11:10.800 a guy named Igor to to thank for that. Yes, 0:11:10.880 --> 0:11:14.600 Igor did a great job. Of all the people who 0:11:15.080 --> 0:11:20.800 experimented with the idea of being able to levitate a person, 0:11:20.920 --> 0:11:23.320 I mean there were there were many, including a our 0:11:23.360 --> 0:11:27.000 our friend Leo, Yeah, Leonardo da Vinci yea. Yeah, he 0:11:27.600 --> 0:11:29.800 tried to create something that he called the air screw, 0:11:29.960 --> 0:11:32.280 which was a screw shape, and the idea was that 0:11:32.440 --> 0:11:36.520 with four people powering this man powered, of course back 0:11:36.559 --> 0:11:39.520 in Leo's day, that if you were able to turn 0:11:39.600 --> 0:11:41.760 this air screw fast enough, it would be able to 0:11:41.760 --> 0:11:45.400 create enough lift to lift the machine off the ground. Now, 0:11:45.559 --> 0:11:49.160 he never got this to work, but it was sort 0:11:49.200 --> 0:11:51.360 of the basis of the idea of what would eventually 0:11:51.400 --> 0:11:55.080 become a helicopter, although it changed dramatically by the time 0:11:55.120 --> 0:11:59.880 the helicopter actually appeared. Yep. Now, Igor Sikorsky, if you 0:12:01.120 --> 0:12:03.719 spend any time at all paying attention to helicopters, that 0:12:03.800 --> 0:12:06.040 name is going to be very familiar to you. Um 0:12:06.400 --> 0:12:09.599 was a Russian who experimented with the idea of helicopters 0:12:09.600 --> 0:12:11.720 and then kind of moved away to get into other 0:12:12.480 --> 0:12:14.920 types of airplane flight and then sort of came back 0:12:14.960 --> 0:12:17.480 to it later on. Yea, His early attempts were not 0:12:17.600 --> 0:12:21.040 met with very much success. Now, so he decided, hey, 0:12:21.120 --> 0:12:23.680 you know what, let's just put this on the back 0:12:23.720 --> 0:12:25.800 burner and look at something that I know will work. 0:12:26.480 --> 0:12:30.720 And then eventually, once he felt more confident, he revisited 0:12:30.760 --> 0:12:33.720 this idea of the helicopter. Yeah, back in the around 0:12:33.720 --> 0:12:36.480 the nineteen thirties, I think is when when he started 0:12:36.480 --> 0:12:38.640 really having some luck with it and he realized that 0:12:38.920 --> 0:12:42.040 he was going to need something to prevent the helicopter 0:12:42.200 --> 0:12:45.320 body from spinning like that without any kind of force. 0:12:45.360 --> 0:12:49.160 So he decided to mount a tail rotor on his 0:12:49.280 --> 0:12:53.000 helicopter too. And basically it's it's creating force in a 0:12:53.080 --> 0:12:56.760 sideways manner that that is resisting the force that that 0:12:56.800 --> 0:13:01.480 would naturally cause the helicopter to turn. So um, you know, 0:13:01.640 --> 0:13:05.480 hats off to igor. Yeah, and that was a brilliant idea. 0:13:05.720 --> 0:13:08.880 It was the nineteen thirty nine when he created the 0:13:09.000 --> 0:13:13.240 VS three hundred, which was based off these early designs, 0:13:13.280 --> 0:13:15.640 and it actually worked. It lifted him up into the air. 0:13:16.200 --> 0:13:18.280 It was a bit of a bumpy ride. But then 0:13:18.440 --> 0:13:21.319 he ended up trying to uh, you know, he refined 0:13:21.480 --> 0:13:26.120 the design of it and then um, actually had broke 0:13:26.160 --> 0:13:30.319 a record. On May six one, he broke the world 0:13:30.440 --> 0:13:34.840 helicopter endurance record and stayed in the air for one hour, 0:13:35.000 --> 0:13:39.600 thirty two minutes and twenty six point one seconds. And yeah, 0:13:39.640 --> 0:13:43.800 that's that's pretty impressive. I mean, for for an invention 0:13:43.840 --> 0:13:46.440 that people had played with for centuries really, but no 0:13:46.480 --> 0:13:49.319 one had really cracked it. It was a big jump. 0:13:49.600 --> 0:13:51.960 And speaking of jumps, we should say that between the 0:13:52.000 --> 0:13:55.080 time of the the top toy that was invented in 0:13:55.200 --> 0:13:59.520 ancient China and the time that Sikorski created the first 0:14:00.520 --> 0:14:03.640 working helicopter, there were a lot of other people who 0:14:03.640 --> 0:14:06.760 were involved in trying to make this work, and some 0:14:06.840 --> 0:14:11.520 of their contributions led into Sikorski's work. Yes, but a 0:14:11.600 --> 0:14:14.520 lot of these early inventions that were created we call 0:14:14.600 --> 0:14:18.320 them hoppers because they could they could lift off the 0:14:18.360 --> 0:14:21.720 ground briefly, but they couldn't really sustain flight for any 0:14:21.800 --> 0:14:23.960 length of time, and they didn't really have any way 0:14:24.000 --> 0:14:26.840 of changing the direction of that flight. It just would 0:14:26.880 --> 0:14:29.880 go up and down, I mean, apart from being pushed 0:14:29.880 --> 0:14:33.720 around by whatever wind happened to be in the area. Yeah, 0:14:34.200 --> 0:14:36.600 being pushed around by wind, that's not a problem. But 0:14:36.640 --> 0:14:39.680 then so he breaks the record. It turns out that, 0:14:39.760 --> 0:14:43.200 you know, the helicopters would become really important in warfare. 0:14:43.880 --> 0:14:48.280 That actually became a very uh well, the United States 0:14:48.280 --> 0:14:52.560 in particular really dependent upon helicopters in conflicts in Korea 0:14:52.640 --> 0:14:56.680 and Vietnam. Hey, you know I've seen mash Yeah, yeah, 0:14:56.720 --> 0:15:01.040 it starts off with one through early morning guy. See 0:15:02.200 --> 0:15:07.360 uh yeah, And this was this was a pretty interesting development. 0:15:07.400 --> 0:15:11.080 I mean you see a lot of of the experimental 0:15:11.120 --> 0:15:16.840 aircraft from that era just became oddities. Yes, yes, which 0:15:17.160 --> 0:15:19.880 you can still find autogyros. And we should explain what 0:15:19.880 --> 0:15:22.800 the difference between an autogyro and a helicopter is. So 0:15:22.840 --> 0:15:25.760 with a helicopter, those rotors were talking about, those are 0:15:25.800 --> 0:15:29.920 powered that that rotor mast turns underpower. There's an engine 0:15:29.960 --> 0:15:33.080 and a transmission. The engine provides power, transmission converts it 0:15:33.120 --> 0:15:35.960 over into the mechanical energy that the rotors need in 0:15:36.000 --> 0:15:41.120 order to turn, and that is what makes the the 0:15:41.160 --> 0:15:44.560 blades turn fast enough to create the lift. Autogyros have 0:15:45.080 --> 0:15:50.200 unpowered rotors, so there is a there there is a 0:15:50.240 --> 0:15:52.680 set of rotors on top of an autogyro, so in 0:15:52.680 --> 0:15:55.680 a way it kind of resembles like a miniature helicopter. 0:15:56.320 --> 0:15:58.560 But then there's a propeller that's either in the front 0:15:58.680 --> 0:16:01.080 or the back of the autogyro. It all depends on 0:16:01.120 --> 0:16:04.640 the design of a specific autogyro, which what that's what 0:16:04.800 --> 0:16:09.120 provides thrust and what happens is it generates an air 0:16:09.200 --> 0:16:12.560 flow that is directed up at the rotors that are 0:16:12.600 --> 0:16:16.640 above the autogyro, and that that upward flowing amount of 0:16:16.640 --> 0:16:19.760 air is what makes the blades start to turn. And 0:16:19.840 --> 0:16:23.120 you just keep increasing the air flow, which again makes 0:16:23.160 --> 0:16:27.320 the blades turn faster until that helps counteract the weight 0:16:27.440 --> 0:16:29.960 of the autogyro. And that's what allows the autogyro to fly. 0:16:30.360 --> 0:16:33.640 But there's no motor turning those blades. It's all just 0:16:33.760 --> 0:16:36.760 from the flow of air. Yeah. As a matter of fact, 0:16:37.320 --> 0:16:41.080 some now, some of the more modern helicopters also have 0:16:41.160 --> 0:16:44.240 a second engine, which can help you know, of course 0:16:44.360 --> 0:16:47.040 if in the case of the first engine going out, 0:16:47.680 --> 0:16:51.000 um but you know there there's some redundancy there, uh 0:16:51.240 --> 0:16:55.680 now in the more modern helicopters, especially for military helicopters 0:16:56.000 --> 0:16:59.840 that might be affected by enemy fire. Right sure, Yeah, 0:17:00.040 --> 0:17:02.000 you have an engine failure, then you can switch over 0:17:02.000 --> 0:17:06.960 to a second engine and hopefully prevent catastrophe. So let's 0:17:07.440 --> 0:17:09.840 talk a little bit about the controls that are inside 0:17:10.000 --> 0:17:12.720 a helicopter. Of course, you have lots of different um 0:17:13.000 --> 0:17:16.800 uh dials and indicators that give you information about the 0:17:16.880 --> 0:17:22.160 environment and uh information about your helicopter's performance. Those are 0:17:22.200 --> 0:17:25.600 all there's they're too numerous to name, really, but the 0:17:25.720 --> 0:17:28.120 actual controls. When we were talking about using both your 0:17:28.119 --> 0:17:31.240 hands and both your feet, well, one hand is gonna 0:17:31.320 --> 0:17:34.680 be on that cyclic pitch lever. So this is the 0:17:34.800 --> 0:17:38.000 lever that controls the angle of each of the rotor 0:17:38.040 --> 0:17:42.399 blades individually. And uh this one is used mainly to 0:17:43.000 --> 0:17:46.000 tilt the craft at either side or forward and backward. 0:17:46.440 --> 0:17:51.639 But it's it's done in uh very it's not it's 0:17:51.680 --> 0:17:54.240 it's not the one that changes the swashplate. That's the 0:17:54.280 --> 0:17:57.040 collective pitch leaver. So that's that's your second one that 0:17:57.040 --> 0:17:59.880 you're holding with your other hand. Um. It's mainly used 0:18:00.080 --> 0:18:03.280 things like take off and landing. It's used to increase 0:18:03.359 --> 0:18:05.639 or decrease the pitch of all the rotor blades at 0:18:05.640 --> 0:18:09.240 the same time. And it's mostly responsible for up and 0:18:09.280 --> 0:18:12.960 down movements, not things like forward, backward, left, right. Uh. 0:18:13.000 --> 0:18:15.960 Then you've got your foot pedals and these are what 0:18:16.119 --> 0:18:21.360 control the tail rotor, and so using the the tail rotors, 0:18:21.920 --> 0:18:25.159 this is how you can turn the the helicopter so 0:18:25.280 --> 0:18:28.600 it faces a different direction. You're not banking it, but 0:18:28.640 --> 0:18:31.080 you're turning it. Um or you're using it just to 0:18:31.160 --> 0:18:34.680 keep it steady. Uh. And and if you're wondering, you know, well, 0:18:34.680 --> 0:18:38.280 what about hovering? Isn't that easy? No, Hovering is actually 0:18:38.320 --> 0:18:42.199 pretty difficult to do because you have to you have 0:18:42.280 --> 0:18:45.119 to get everything in a neutral position, and then you 0:18:45.119 --> 0:18:48.280 have to keep making minor adjustments in order to maintain 0:18:48.400 --> 0:18:50.919 the position that you're in. In fact, pilots will have 0:18:51.000 --> 0:18:55.520 to pick a spot that they can look at and 0:18:55.840 --> 0:19:00.280 try and maintain their attitude and altitude uh by by 0:19:00.320 --> 0:19:05.920 referencing where that spot is and making minor adjustments constantly. Yes. Yeah, 0:19:06.119 --> 0:19:09.920 and it helps to uh to have um uh an 0:19:09.920 --> 0:19:13.960 experienced pilot on board, just because not only is there 0:19:14.200 --> 0:19:19.520 the matter of looking at the electronic components in the 0:19:20.000 --> 0:19:24.240 craft itself, but to orient him or herself with the 0:19:24.359 --> 0:19:28.159 land around, just to to give a visual representation of 0:19:28.200 --> 0:19:30.200 what's going on. And that's that's one of those things 0:19:30.200 --> 0:19:34.520 that's especially important. Because the wind does blow helicopters around. 0:19:35.000 --> 0:19:38.200 You have to take these things into into account, and 0:19:38.320 --> 0:19:40.119 um one of the best ways to do that is 0:19:40.160 --> 0:19:42.560 to use that visual orientation to make sure that you 0:19:42.600 --> 0:19:48.160 haven't drifted off to some degree. Now, let's talk really 0:19:48.240 --> 0:19:50.520 quickly about what the process is like if you are 0:19:51.400 --> 0:19:56.600 taking off helicopter, So there's several steps. First, what you 0:19:56.600 --> 0:19:58.840 would have to do is you have to open up 0:19:58.840 --> 0:20:01.800 the throttle that you and speed up these rotors so 0:20:01.840 --> 0:20:03.720 that they start turning out a speed fast enough to 0:20:03.760 --> 0:20:06.239 create the amount of lift you need. UM you do 0:20:06.320 --> 0:20:08.560 this by actually twisting the handle of one of the 0:20:09.040 --> 0:20:12.000 levers you're holding in your hands and twisting it one 0:20:12.040 --> 0:20:14.240 way opens the throttle and twisting it the other way 0:20:14.359 --> 0:20:17.320 closes the throttle. So that's you know, that's essentially like 0:20:17.359 --> 0:20:22.359 sitting stepping on the accelerator of a of an automobile. UM. 0:20:22.440 --> 0:20:25.040 So the next what you would do, once you've got 0:20:25.080 --> 0:20:28.720 the the rotors moving at the right speed, you'd start 0:20:28.760 --> 0:20:32.960 to pull back on the collective control and that's what's 0:20:32.960 --> 0:20:37.080 going to raise the swashplate assembly and that's going to 0:20:37.200 --> 0:20:39.720 change the pitch of the rotor blades, and then that's 0:20:39.760 --> 0:20:43.720 what's going to let you direct that lift the in 0:20:43.720 --> 0:20:46.199 the right direction so that you can actually get off 0:20:46.240 --> 0:20:51.560 the ground. Then you would start to press down on 0:20:51.720 --> 0:20:55.920 the left foot pedal because you would need to get 0:20:55.960 --> 0:20:59.760 the tail rotor spinning so that you could counteract that torque. 0:20:59.800 --> 0:21:02.440 We we're talking about the the the tendency for the 0:21:02.960 --> 0:21:05.359 chassis to spend in the opposite direction of the rotors. 0:21:05.600 --> 0:21:07.320 Right as soon as you're lifting off the ground, you're 0:21:07.320 --> 0:21:09.640 going to be it's going to be much easier for 0:21:09.680 --> 0:21:12.639 the rotors to start to spin the body of the helicopter, 0:21:12.680 --> 0:21:14.880 the fuselage. Yes, so if you weren't, if you were 0:21:14.920 --> 0:21:18.080 not making that rotor tail rotor spin, you would start 0:21:18.119 --> 0:21:20.679 to go on a little spinny spinny d it yourself, 0:21:20.720 --> 0:21:24.680 which would most likely end in disaster. Yeah, so yeah, 0:21:24.800 --> 0:21:30.520 you you then would start to actually add a counteractive 0:21:30.560 --> 0:21:35.160 thrust through the tail rotor by pressing down that left pedal. Now, 0:21:35.160 --> 0:21:36.560 if you got to a point where you needed to 0:21:36.600 --> 0:21:39.080 turn or you need to slow that down, you could 0:21:39.840 --> 0:21:42.640 stop pressing down the left pedal and start pressing down 0:21:42.720 --> 0:21:46.320 the right pedal, and that's what would counteract that. Um. 0:21:46.440 --> 0:21:49.800 Then you keep pulling back on that collective control while 0:21:49.880 --> 0:21:52.960 holding down the left foot pedal, and once the correct 0:21:53.000 --> 0:21:57.000 amount of lift is created, your helicopter will leave the 0:21:57.040 --> 0:22:01.080 ground and you'll be flying over the air and delivering 0:22:01.080 --> 0:22:07.560 traffic reports like nobody's business. All right, let's uh, let's 0:22:07.560 --> 0:22:11.080 take a quick break. I'm still recovering from my truly 0:22:11.640 --> 0:22:16.800 awful and unrecognizable Schwarzenegger uh impersonation. Let's take a quick 0:22:16.800 --> 0:22:29.120 break to think our sponsors. Yeah, it's um, it's pretty interesting. Uh. 0:22:29.520 --> 0:22:33.359 And there's even other challenges to flying a helicopter, right, 0:22:33.359 --> 0:22:35.800 I mean, not only is it requiring a lot of coordination, 0:22:36.400 --> 0:22:40.240 but even just the way that the air flight works. 0:22:40.240 --> 0:22:43.639 When you start traveling, say forward, you're moving forward at 0:22:43.720 --> 0:22:48.199 at around UM twenty knots of airspeed, you have to 0:22:48.560 --> 0:22:52.040 end up transitioning, transitioning from hovering, which is more or 0:22:52.119 --> 0:22:57.440 less staying fairly stationary, to moving on a full forward 0:22:57.480 --> 0:23:01.879 flight phase. And there's that's where you have the effective 0:23:02.040 --> 0:23:07.000 translational lift or et L. And at that point the 0:23:07.000 --> 0:23:09.640 pilot would start to ease up on that left foot 0:23:09.680 --> 0:23:13.200 pedal and move closer to a neutral setting. And there's 0:23:13.200 --> 0:23:16.400