What happens if you ROLL an airliner?!

hi everybody better complement or not a video podcast is always hope you're doing absolutely fantastic on the videos there guys I'm gonna show you inside of the simulator what happens if an aircraft turned too much what happens if your overbank or if you get into an upset situation where the aircraft is turned completely all over I'm going to tell you a little bit about why we bang as much as we do during normal operations and I will also explain a bit about the systems behind so stay tuned [Applause] this video is brought to you in cooperation with Skillshare now Skillshare is an online learning community with thousands of high quality courses in pretty much any subject that you can imagine if you want to improve on your public speaking skills or you want to learn how to fly using your own flight simulator at home well then the five on the first of you who uses this link here below will get two months of premium membership of Skillshare absolutely for free so check it out [Music] right guys so the bank angles of an aircraft us in how much the aircraft is tipping over as it's turning is something that I know is causing a lot of concern to a lot of people out there I always get questions so why does the aircraft has to to turn that March you know it's really scary well in order to understand that we need to first all understand how it works you know what kind of systems are involved and then we need to understand whether or not it's actually dangerous to make high bank angles and you know at what point does it become a problem so first of all the systems involved so we have two different flight control surfaces that we use to turn the aircraft in its roll axis as in like this the the first primary brothers were using our ailerons those are the little rods that you can see on the tip or close to the tip of the wings and trailing edges of the wings and the way that they will work is that they literally decrease the amount of lifts the wing has on that side and increases on the other side if it wants to turn or roll a aircraft like this now on top of that we also have something called flight spoilers and flight spoilers are those little flaps that you can see on the top side of the wing and the way that they work is similar they will come up on the side that we want to drop so by doing so they also decrease a little bit of lift on that wing makes that wing drop and subsequently the other one will go up so those are the systems on the rudders involved they are hydraulically activated but they're also connected through wires from our yoke out through the wings to activate the at least ailerons not the flight spoilers so why do we have to bank them well in order for you guys not to be like you would be if you were sitting in a rally car and we suddenly turned sharply to left or right you would be pushed out towards the outside of the turn okay so we won't we don't want that we want you to have a pleasant ride okay and the only way that we can do that is by both turning the aircraft in its yaw axis like this and we do that using the rudder and the yaw damper and also in its roll axis like this if we combine those two movement it means that the aircraft will make a nice coordinated turn and you will be able to sit in your seat with a cup of coffee in the only way that you'll notice that you're turning is by looking out and seeing that you're actually banking okay so that's a coordinated turn and that's what we're trying to achieve when we turn during normal operations we want to try to achieve something called a rate 1 turn that is a turn that gives us three degrees of heading difference per second it means it takes us one minute to turn the aircraft 180 degrees around and it takes us two minutes to make a complete circle the reason we want to do a rate 1 turn is because air traffic control need to be able to know how quickly we will achieve the heading they are giving us and it also gives some kind of structure to for example holding patters how long a holding pattern will take so we do that and in 737 giving the normal speeds that we fly that means that we need to bank with about 25 to 30 degrees so when you're out flying when we initiate a turn where you will see about 30 degrees of Bank very rarely or almost never any more than that the only reason that we would ever turn with more Bank angle than that would be to avoid an obstacle or to get ourselves out of an upset situation which is what I will show you soon in the video coming up and but during our training when we do our type rating we do something called a steep turn maneuver and that is this turn that we initiate to 45 degrees so 15 degrees more Bank than we would during a normal turn the reason we're doing that is because it's a great way of increasing what we call the scan speed of the pilot we have to as pilot be able to interpret a lot of different instrumentation in real time in order to understand what the aircraft is doing and on a primary flight display which is the instrument that we have straight in front of us we have the the attitude indicator in the middle that shows us how much we are pitching up and down and how much turning left and right and gives us the horizon we also have to the left the airspeed to the right we have the the altitude and below we can see our heading to the far right we also have something called an IV si which is an instantaneous vertical speed indicator now all of those instruments will be involved when we're doing a steep turn and when you're doing a steep turn as in when the bank angle is increased above the normal 30 degrees you will also have an increase in load factor you have a small increase in load factor already 30 degrees but it's not that much now the load factor is is there because when you're flying an aircraft in level flight the the lift from the wings is perpendicular to the wing so it's straight up so if you're flying like this you can imagine that the lift is going straight up like that in order to keep the altitude but as we're turning like this now the little wing is still perpendicular right but all of a sudden instead of being a lift vector like this it's now a lift vector like that so this means that the actual part of the force that is keeping us at the altitude it's much smaller and you have a side vector as well right so given that if you need to maintain your altitude you understand that you need to actually pull a little bit on the elevator as well in order to make the lift higher bigger to get the same vector keeping us at altitude so that's what we have to do as you initiate the turn and coming up to 30 degrees you have a little bit of back pressure using your elevator when you're increasing the turn even further than that you now need to pull more and more on your elevator to maintain the altitude but when you're doing so you're actually increasing your drag as well so you need to add a little bit of trust and the stall speed of the aircraft as in the speed where the wing is not aerodynamically effective anymore when it starts to fall that increases with a square root of the load factor so this means that from zero degrees a bank up to 30 there's not too much increase in the stall speed but as you go up to 45 it's a bit more as you go up to 60 it's even more and it increases exponentially so you will see this in the video very very soon when I start to go up to 60 degrees and beyond that it is almost impossible to maintain the altitude of the aircraft you have to pull a lot on our yoke in order to maintain altitude and as we do so you can see on the speed tape that the stall speed the little red barber sports is gonna come shooting up from below and eventually if you continue to do that continue to pool I will stall the aircraft and have to recover it out of the stall okay so this is something that's worth noting before we start looking at the video now what I want you to look at specifically is how the aircraft the warning systems that the aircraft has for example when we bank more than 30 degrees nothing happens up to 35 degrees but at 35 degrees the bank angle indicator which is at the top of the parameter flight display will turn amber and then at 35 degrees we get an aural warning from the aircraft saying Bank angle Bank angle and that warning will repeat itself for each five degrees more so I'm 35 degrees at 40 degrees and it's 45 degrees now if we don't do anything it's just a one-time warning it will not be continuous like a stick shaker or a stall one it will be um but look at that look at what happens to the instrumentations and specifically look at what happens to the stall speed when I increase the bank angle further now in the middle or a flurry at the end of the video I will be showing you an upset as well now there is no way that a an aircraft flying commercial operation would ever roll okay the only reason that a commercial pilot would ever consider rolling an aircraft is if we would end up in an opposite maneuver after for example having hit the wake turbulence behind heavy aircraft in front this is why we have separation in time and in altitude between aircraft to make sure that we don't found ourselves in situations like that but if we do if the aircraft is being flipped over more than 90 degrees it might actually be quicker to continue the role in order to get back up straight again then it would be to stop the roll and go back so this is one of the few reasons I will show you this that we would ever do that now some of you will ask well I've seen I've seen a 707 roll and it's true there was a famous test pilot called Tex Johnson who was a text pilot on the Boeing 707 who did a barrel roll in front of thousands of people in Seattle back in the back in the day but what you have to understand is that is a it's a first of all the barrel roll is a it's a controlled maneuver which is only subjecting the aircraft to 1g which means that there's no increase in load factor if you do that correctly and it was done by a pilot who was highly skilled trained in an empty aircraft with loads of excess trust you would never ever see a real aircraft in transport with passengers on board and do something like that so enjoy the video make sure that you send in your questions afterwards right everybody very welcome to VA airline trainings brand spanking new 737 simulator here in Cambridge what we are going to do and what I'm going to show you today is basically what happens if we overbank an aircraft and the first part of the exercise is something that we do during the tight braiding which is to would make the aircraft bang to 45 degrees which is about 15 degrees more than you will ever ever fly an experience as a passenger and the reason for the exercise is to increase the pilots can speed it means that it helps us to practice to watch all of our instruments at once basically to make sure that we can maintain a certain value but what I will show you is also what happens when we increase the bank angle even further so the first thing we're going to do is we are going to established aircraft here at about 10,000 feet at about 250 knots we are at a subtly heading now 180 degrees we will make a 360 degree turn to the left to start with so the first thing I will do is I will initiate the turn with the normal bank angle s and so much that you are used to when you're sitting as passengers so here we are we're about 28 degrees Bank at the moment so 28 to 30 degrees is something that you would have seen normally and as you can see on the horizon you know it's it's a fairly you know a fairly high Bank angle but it's not that much now yes I increase the bank angle it becomes harder and harder to maintain the altitude and that is because of the secondary effect of the elevators so here are 10,000 feet and will increase it now to 45 degrees Bank and as I do so I add a little bit of trust because we will get more more drag Bank angle so that's the bank angle warnings you can see it slightly above two and a half degrees of the trouble Bank angle and as you can see it's very easy to get the aircraft started to the same angle so here we are a little bit for more than 45 degrees of Bank and it's maintaining the altitude quite okay at the moment but I do need quite a bit of back pressure now in order to maintain the altitude now you should not use the trim in this case so do not trim the aircraft when you do this exercise because when you do if when you are about to level off the turn you're then going to start climbing so I've lost about 100 feet there try to regain that so I decrease the bank angle get it back up again a little bit and then I increase the bank angle again that so now will increase the bank even further to 60 degrees angle now here a significant amount of back pressure and as you can see at the bottom of this speed indicator there we're starting to see the barber's poles Bank angle hang on I got through 180 degrees just to continue to show you go all the way up to 60 degrees and as you can see as I'm increasing now the aircraft stalls roll out of the bank and stabilize the aircraft again so that's a good example of the stall speed increasing as you're increasing the g-forces that you're taking up of the aircraft so since the stall speed increases with the square root of the g-force that you're taking out as we're banking normal degrees about 30 degrees or so it's not too much happening but as you increase the 45 degrees a little bit more 60 degrees you have an almost 40% increase and as you go further than that we'll learn the stall speed would increase to about 100 percent so let's see I'm not I'm talking too much flying too little at the moment you're getting back to to a flat of 100 and 250 knots and I'll show you that thing again little bit of thrust off initially here establish the aircraft at 10,000 feet and then we initiate a bank in the other direction is that that's coming up to 30 degrees a bank just a little bit a back pressure needed very little but as he falls 30 degrees increased little bit of trusts increase the bank angle Bank angle Bank angle 45 degrees and there goes need a bit of a descent corrected immediately do not very easy to to get into the habit of dreaming but do not do that and there we go it seems like three degrees pitch up will maintain the altitude quite nicely at they speed and at this altitude because this all differs depending on what altitude you're at so if you now increase the bank further giggle Bank angle increase the trust further more about Russia needed Bank angle even more trust in thinking more back pressure at all and here we're up to almost sixty degrees so it makes it almost impossible to maintain on there that's the stall speed coming up so decreasing the bank angle rolling it out and getting it back to 250 knots so the Boeing 737 is an air transport category aircraft it is not built to do aerobatics with and you can as you can clearly see as the Bank angle goes over 60 degrees the aircraft's start to have problems maintaining the maintaining well above the stall speed basically so I've had a lot of questions can you roll a seven three seven and the answer to that is it is possible to roll it you are going to need extra airspeed so you're going to do it in the descent but it is not something that you would ever see anyone do not even during flight shows the only chance that you will get to see that will be if an aircraft would be in an actual upset so that would be if we would end up in the vortexes behind another aircraft for example and the aircraft gets turned over its keel and the quickest way to regain a normal kind of sunny-side up attitude is to roll around it so that's the only time that you would ever see something like that happening but if we would be in a situation like that I'll see if I can induce it and I see if we can show it to you ready yep Bank angle Bank angle Bank angle Bank angle [Music] there we are but as you can see guys this is never something you would ever want to find yourself in and if you do you have to react very very quickly to it it's it's very close to the maximum structural load that the aircraft can take and if we pull too much in any direction it's you you could actually structurally damage the aircraft so this is why we practice we don't practice in scenarios as extreme as this as because of an aircraft the size of the 737 it's very unlikely that even if they enter into a wake turbulence that we would actually be flicked more than 90 degrees off but if we do it is possible to do it but you have to react lightning fast if it happens right I hope you enjoyed that you might ask yourself has this actually happened in real life and it has so there was a famous incident of a Learjet 45 in Mexico City that crashed inside of central part of Mexico City due to having got into the wake turbulence of a much larger aircraft in front that they were flipped completely over but they did not have enough altitude to to regain full control before they hit the building because as you could see on the video we do lose quite a lot of altitude during a maneuver like that I want to say a special thank you as well to VA airline training who let me borrow their flight simulator up in Cambridge yesterday and I also want to send a specific thank you to the sponsors of this episode which is Skillshare now Skillshare if you haven't checked them out I highly recommend you to do so they're an online learning community with thousands of courses in pretty much anything that I have ever ever looked for inside I've found something about ok something that will be specific interesting for you would be there the course in how to use your home flight simulator in order to prepare for your private pilot license so just go into Skillshare use the link here below the 5 on the first door so we'll get two months or their Premium Membership completely for free so you can just use that link type in pilot or flying and you'll find that course and it will help you to prepare for your PBL so have an absolutely fantastic day wherever you are out there continue to send in your questions to make sure that you have liked and subscribe the channel and I'll see you next time [Music]

Channel: Mentour Pilot

Views: 973,339

Keywords: Steep turns, Aircraft Rolling, Aviation, Avgeek, Pilot, Pilot skills, Over bank, Wake turulence, Turbulence, Fear of flying, fear of flight, Aviation facts, Aviation Explained, Mentour Pilot, Mentour, How to become a pilot, pilot life, flight, flight school, cadet, Boeing 737, Boeing 737MAX, Boeing 737NG, Airbus 320, Airbus 380, Concorde, Boeing 747, Landing, Takeoff, Aerobatics, Boeing roll, Captain, First officer, Commercial aviation, Aviation Youtuber, Success

Id: JhzaogGQNFU

Length: 21min 52sec (1312 seconds)

Published: Fri Dec 14 2018