We hope today's Wonder of the Day took you to new heights! Be sure to grab a friend or family member to help you explore the following activities:. Hi, zack! We encourage you to read the Wonder very closely to learn more. You can also keep researching at your library and online. Hey there Aidan, helicopters transport lots of cargo, so they need to be large enough to carry all of that! Thanks for sharing your comment! Higgins' Class!
How cool that our helicopter Wonder connects to your lesson today! The forward movement the helicopter needs in order to take off comes from the rotation of the rotor blades! We Wonder if you can do some more research of your own about helicopters' use of force and motion! Keep up the great work, Wonder Friends! We're glad you thought it was cool!
Awesome, we're glad you liked today's Wonder Ryleigh! We can't take credit for the Wonder video today but we hope the group of students reached the 10 foot requirement! They have been working so hard!
We can't believe all the different types of helicopters that exist! We are glad that you liked today's Wonder-- we hope you have a terrific Tuesday! WOW, how cool, Daniel C! We are so impressed with your interest in helicopters-- way to go! We hope your remote control helicopter turns out great We are so excited that you enjoyed today's Wonder, Mrs. Thomas's Tigers! How exciting that some of our Wonder Friends are going to be pilots when they grow up!
We can't wait to find out what tomorrow's Wonder, Merrick! It's going to be a great one for sure! We think you did a great job of summarizing the hard work of the team!
We learned what the word "perseverance" means today, too! We're so happy to Wonder with you-- we are smiling ear-to-ear! Have a terrific Tuesday! We bet flying a helicopter with your arms and legs is tough and challenging, but very rewarding! We're glad today's Wonder made you smile, Berkleigh!
Thanks for commenting! We can't take credit for today's Wonder video, Jordan, but we are very impressed by the hard work of the helicopter team! We are so excited that today's Wonder was right up your alley! We can't take credit for the helicopter, but we're excited that you enjoyed today's Wonder!
We aren't the team of engineering students, but we're glad to share some cool information about helicopters with you! We think they are fearless and determined! We were very impressed, too, Kayla R! We hope they win the award! Thanks for sharing your comment, Wonder Friend! We sure do, too, Erick! The team working on the helicopter is incredible and we hope they are successful!
We certainly agree with you, Katelyn! We are very impressed with the helicopter itself and the pilots who lift it off the ground! There is a lot of hard work involved! We are really glad this was a Wonder you enjoyed! There were so many people working together to help the helicopter and the pilot get off the ground! It was so incredible to watch! We're happy that today's Wonder was right up your alley, Michael! Thanks for sharing your comment at Wonderopolis today! We sure hope to see you soon, Wonder Friend!
We were very impressed by today's Wonder, Emily! It was fun to watch the team work together to reach a goal-- especially when the helicopter and pilot reached 8 feet in the air! We know they are working on a safer, smoother landing and we hope they reach the 10 foot requirement, too!
You never know, Bryleigh, you could be the next great helicopter pilot! We like that you checked out today's Wonder and learned something new! Thanks for joining the fun today-- we'll see you soon! What a great word to describe the helicopter team, Julian! Nice work! They are a group of people with a lot of perseverance! We hope they succeed in reaching the 10 foot requirement-- it would be a great accomplishment! We're so excited that today's Wonder was right up your alley, Jason!
We can't take credit for creating the helicopter, but we are so proud of the hard work the students and the pilots have shown! We hope they keep up the hard work to reach 10 feet with their human-powered helicopter!
It's so much fun to Wonder with you, Jason! We agree, Jauquin! We bet it took a great deal of hard work, planning and determination to build that helicopter! It's pretty awesome to see it flying with the help of the pilots! We really liked today's Wonder, too, Azhir! We think the students and the pilots worked together like a team to reach their goal! We learned so much from today's Wonder and we're glad to hear that you did too!
We Wonder if you will create something like a human-powered helicopter in the future!? We certainly agree, Pablo! We bet it takes a great deal of determination to succeed- we hope those students and the pilots win! These students and pilots have really tried their hardest, great point, Kamaria! We hope they are successful and win the prize for their awesome invention!
We bet they are working hard to create a safe, soft landing for the helicopter and the pilot! Wasn't that an amazing Wonder video, Henry!? Collin and Henry must be very powerful to get the helicopter so high off the ground! Great point, Carla! To turn while in forward flight the pitch of each main rotor blade is adjusted individually to effectively lean the rotor disk in the direction of the turn. This statement is about as basic as I can word it to give you the quick answer.
To find out the more in-depth answers to how a helicopter turns and banks be sure to read on…. For this article, we will keep it simple and talk about a helicopter with skids and not wheels and built in North America so the main rotor rotates anti-clockwise when viewed from the above. For reference: helicopters built in Europe tend to have the main rotor turn clockwise when viewed from above.
Turning a helicopter while in the hover for helicopters without wheels or for turning while taxiing for helicopters with wheels is done by the Tail Rotor. In a hover, the forces acting on a helicopter are all equal, thus it should not move. To keep the helicopter from spinning around, the thrust produced by the tail rotor matches the force of the fuselage wanting to turn. Thus everything is in equilibrium and the helicopter keeps pointing forward.
This is where it gets a little more complex so I hope I can explain this clearly. When a helicopter is in forward flight at a constant speed and constant height the following forces are acting upon the aircraft:. Hope you won't hate me for that? As you can see, the whole rotor is turned, causing the helicopter to move in a certain direction, as shown in this image by AVstop The collective determines the amount force generated by the main rotor The anti-torque rotor is used to rotate the helicopter, as shown here, obtained from Gunschip Academy : The main rotor will induce a torque on the cabin, making it spin.
It changes blade pitch differently depending on their position. Also, the aspect that to keep the heading constant, the tail rotor must generate a "base" force to counteract the torque that is generated by spinning the main rotor. The picture hints into that direction, but the text does not comment on it. The pedals control yaw, regardless of the mechanism. In order to keep the explanation simple and concise, I therefore only explained this type of helicopters. Show 4 more comments.
As ROIMaison states, the cyclic control tilts the rotor disc as required. Please excuse my lousy drawing skills. Disc level Disk titled Because the vertical component is now reduced the total thrust is the sum of the vertical and horizontal component , the helicopter will descend slightly since the vertical thrust no longer balances the weight.
Simon Simon There is no mechanism on board to tilt it. Instead, rotor pitch is varied along the rotational axis so the blades generate more or less force on the left or the right disc sector, and AS A RESULT the disc tilts. There is no specific hardware for the tilt.
Collective and cyclic both control the blade pitch. Collective does it equally for all blade "location" on all circle sectors, while cyclic changes the blade pitch differently for different circle locations. Otherwise, I could write words to include the differences in attitude and altitude control in different phases of flight to include dyssemmetry of lift, inflow roll, blowback, translational lift, tail rotor couples etc etc.
Of course, moving the cyclic results in tilting the disc but is this really relevant in this case? For me, personally, it was a real "aha! Until then, I kept searching for the "tilter" on helicopters, and nobody understood what I was asking for.
So I am not saying that I know better. I am just trying to point out that this is an aspect that is imho central to understanding where the "tilt" comes from. Show 1 more comment. Altitude Control In order to change the altitude the flight path needs to be increased or decreased. The flight path needs to be changed via a short vertical acceleration to bend it.
This is too simple an explanation for helicopters. To climb, you first adopt a climbing attitude by pulling back on the cyclic. This starts the climb. Since the total thrust vector is now more vertical you are climbing an increase in power is needed to maintain speed a helicopter can climb or descend with zero forward or backward speed.
As more power is required, trim changes are required to maintain direction. You do not start a climb by pulling collective since this will result in an increase in speed. Descending is power, then attitude, then trim. Only hover is special. Please tell me which fixed wing control provides the same functions as the collective lever? Since you assert that the control inputs are the same, there must be one? I'm going to give up. You were wrong to say that helicopters behave like fixed wings and have the same control inputs in all manouveurs except for hover.
The is just plain wrong. You are also wrong about "rotor power" but since you have not stated your qualifications, nor have you read up on the appropriate references, I see no point in going on. Show 12 more comments. Can someone clarify the relationship between aircraft speed, torque, prop length and pitch and how this applies to a helicopter. If the motor stops the blades will stop. There are a few quick points that can be made here about this question.
All helicopters have a freewheel system, sometimes called a sprag clutch or freewheel unit. It works just like most bicycles, in the way that if you stop pedaling the wheels keep turning until you run out of momentum.
The same applies to the blades on a helicopter if the engine stops. Even with a freewheel system, once the momentum runs out. If the pilot does nothing they will! However, in the event of this happening the pilot allows the helicopter to descend and, as it does, the air it descends through drives the rotors, keeping them spinning.
This is called Autorotation.
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