Jump to content

Tail boom


Recommended Posts

any one can explain the advantae and use of tail boom in helicopter?

What purpose we are using tail boon?

why we need tail boom?

 

please post the information

if its possible send it to my mail id vincent_svt@yahoo.co.in

 

 

 

 

 

regards

vincent ryan

Link to comment
Share on other sites

Here is a brief description from Wikipedia along with the weblink:

 

----------------------------

http://en.wikipedia.org/wiki/Helicopter

 

Antitorque

With a single main rotor helicopter, the creation of torque as the engine turns the rotor creates a torque effect which causes the body of the helicopter to turn in the opposite direction of the rotor. To eliminate this effect, some sort of antitorque control must be used, with a sufficient margin of power available to allow the helicopter to maintain its heading and provide yaw control. The three most common controls used today are the traditional tail rotor, Eurocopter's Fenestron™ (also called a fantail), and MD Helicopters' NOTAR®.

 

Tail rotor

The tail rotor is a smaller rotor mounted vertically or near-vertical on the tail of a traditional single-rotor helicopter. The tail rotor either pushes or pulls against the tail to counter the torque. The tail rotor drive system consists of a drive shaft powered from the main transmission and a gearbox mounted at the end of the tail boom. The drive shaft may consist of one long shaft or a series of shorter shafts connected at both ends with flexible couplings. The flexible couplings allow the drive shaft to flex with the tail boom. The gearbox at the end of the tailboom provides an angled drive for the tail rotor and may also include gearing to adjust the output to the optimum RPM for the tail rotor. On some larger helicopters, intermediate gearboxes are used to transition the tail rotor drive shaft from along the tailboom or tailcone to the top of the tail rotor pylon which also serves as a vertical stabilizing airfoil to alleviate the power requirement for the tail rotor in forward flight. It may also serve to provide limited antitorque within certain airspeed ranges in the event that the tail rotor or the tail rotor flight controls fail.

-----------------------------

Link to comment
Share on other sites

Wow- Roger, you have more patience than I do !!!!!!!!

 

Amen to that! I was gonna add an answer like "to hold the tailrotor up!" But wow! :lol:

Edited by Fastlane
Link to comment
Share on other sites

I wouldn't say you are required to have a tail boom...just look at the CH-47 Chinook with the tandem rotor blades. If you are not doubling up the main rotor then you should have the tailboom for anti-torque requirements, whether it be T/R blades, Fenestron, or NOTAR. In addition, the tailboom fits the horizontal and vertical stabilizer providing extra stability at higher airspeeds. I wouldn't say there is an advantage and it depends on the model helicopter you are comparing. ;)

Link to comment
Share on other sites

The tail rotor provides a Moment, which is the force developed, multiplied by the distance from the fulcrum.

 

For a given torque produced by the engine / transmission, you could have a weak tail rotor (which sucks less power from the engine) on a really long boom, or a powerful tail rotor on a really short boom.

 

There are problems with building a long boom - it doesn't fit in the hangar, too hard to do a pivot turn, and the mechanical aspects of a cantilever that is sixty feet long mounted on an el-cheapo fuselage frame.

 

There are also problems with a short boom, where the rotor is under the main rotor disc - lots of interference, clearance worries when the disc flexes down, clearance from the ground, and so on.

 

So, most manufacturers put the tail rotor just outside the disc as a compromise. More expensive machines put the T/R on top of the fin to solve some aerodynamic problems, but this introduces other problems of cost, complexity, and resonant frequencies.

 

Others, like the Kamov, use two counter-rotating main discs and don't need a T/R or any more boom than a simple stabilizing/steering vertical fin.

Link to comment
Share on other sites

Others, like the Kamov, use two counter-rotating main discs and don't need a T/R or any more boom than a simple stabilizing/steering vertical fin.

 

How do you control yaw in a tandem rotor or counter-rotating design? Is it by controlling the torque going to rotors (eg, to yaw right, decrease power to the counter-clockwise turning rotor)?

Link to comment
Share on other sites

I wouldn't say you are required to have a tail boom...just look at the CH-47 Chinook with the tandem rotor blades. If you are not doubling up the main rotor then you should have the tailboom for anti-torque requirements, whether it be T/R blades, Fenestron, or NOTAR. In addition, the tailboom fits the horizontal and vertical stabilizer providing extra stability at higher airspeeds. I wouldn't say there is an advantage and it depends on the model helicopter you are comparing. ;)

 

A CH-47 DOES NOT HAVE TANDEM ROTOR BLADES, IT HAS 2 SEPERATE ROTOR SYSTEMS.

Link to comment
Share on other sites

Guest pokey
A CH-47 DOES NOT HAVE TANDEM ROTOR BLADES, IT HAS 2 SEPERATE ROTOR SYSTEMS.

 

in TANDEM,,, of korse ! of korse !

 

i always wanted to take 2 300's: remove the tail rotor from 1,,,,, the complete tail boom & tail rotor from the other,,,,,, bolt ship 2 to the rear of ship 1 & voilla ! CH300 !

 

1) would make a reliable, time proven twin engine

 

2) 6 passengers

 

3) cheeper than 2 300's ( can sell the 2 spare T/R's & spare boom)

 

4) impossible to park in hangar backwards

Link to comment
Share on other sites

in TANDEM,,, of korse ! of korse !

 

i always wanted to take 2 300's: remove the tail rotor from 1,,,,, the complete tail boom & tail rotor from the other,,,,,, bolt ship 2 to the rear of ship 1 & voilla ! CH300 !

 

1) would make a reliable, time proven twin engine

 

2) 6 passengers

 

3) cheeper than 2 300's ( can sell the 2 spare T/R's & spare boom)

 

4) impossible to park in hangar backwards

 

NOW THAT IS A SMOKIN IDEA!!!

Link to comment
Share on other sites

Hey, Vincent!

 

Read the posts!

 

Purpose is to:

1. Mount an anti-torque device at a suitable distance from the mast to enable control of torque

2. Mount a vertical fin to provide some directional stability in yaw

3. Mount a horizontal stabilizer to provide some stability in pitching plane, and to provide a downforce to keep the cabin more horizontal in forward flight, otherwise it wants to ride nose down, which is uncomfortable.

 

To answer the query on Kamovs, yes, yaw is controlled with differential collective.

 

The Chinook rotors are Tandem, and are not separate in the true sense. They are linked together, and the blades mesh over the fuselage. Yaw is controlled by differential cyclic. There is also an electric trim, to tilt both disks forward in forward flight, to keep the fuselage more level.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...