NOTARs
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I''ll huff, and I''ll puff, and I''ll Blow....wait, wrong story....
The Notar technology is similiar to any tail rotor driven design, however the drive of the air comes from a fan located at the front of the tailboom and directs the air thru an aerodynamically shaped tailboom and directional control is provided by a moveable thrust cone.
Should engine power be lost, the fan is still driven the same way the tail rotor on conventional aircraft would be, thus allowing the pilot to maintain directional control.
Now, should the pilot be doing aerobatics....oops, that was another topic....
The Notar technology is similiar to any tail rotor driven design, however the drive of the air comes from a fan located at the front of the tailboom and directs the air thru an aerodynamically shaped tailboom and directional control is provided by a moveable thrust cone.
Should engine power be lost, the fan is still driven the same way the tail rotor on conventional aircraft would be, thus allowing the pilot to maintain directional control.
Now, should the pilot be doing aerobatics....oops, that was another topic....
Bruised Armpit
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Has anyone ever seen a swivelling tailrotor? Something that would rotate 90degrees at the gearbox to provide forward thrust in forward flight?
Oh yea of the one flying without the benefit of hydraulics.
Your idea has merit, allthough the engineering required on a conventional tail rotored machine would be astranomical. The concept of thrust would be better applied to the Notar concept.
No disrespect intended, just apply a little theory of flight.
P.S Fly helicopters with power stearing only.
CHEERS
Your idea has merit, allthough the engineering required on a conventional tail rotored machine would be astranomical. The concept of thrust would be better applied to the Notar concept.
No disrespect intended, just apply a little theory of flight.
P.S Fly helicopters with power stearing only.
CHEERS
Now Blackmac:
If you refer to Hyd as power steering, I should have to ask you to hold your handle a little, since my steady stead don''t have any! (S300CB). But you could come over, and give me a ride in one with, and I''d be much obliged!!
If you refer to Hyd as power steering, I should have to ask you to hold your handle a little, since my steady stead don''t have any! (S300CB). But you could come over, and give me a ride in one with, and I''d be much obliged!!
Sharky,
The NOTAR uses a combination of technologies to create anti-torque.
The primary thrust is created by air through a nozzle at the end of the tail. This has the same effect as a tail rotor - pushing air against the direction of rotation to counter the torque. In most helicopters the fan that creates this thrust is at the end of the tail boom, in the form of a traditional tail rotor or Fenestron. In the NOTAR, the fan is mounted inside the boom, in the intracostal area where tail boom attaches the main fuselage section. The pressure it creates is ejected through a nozzle at the end.
The NOTAR also takes advantage of the Coanda Effect created when the main rotor downwash flows past the tail boom. The shape of the boom creates an attraction to the airflow, and thus anti-torque force.
The fan is driven by the same drivetrain that powers the tail rotor in thr traditional Hughes or MD products, so the answer to your second question is 'YES'. You still have yaw control with no hamster.
Oops. Just read Mag's explanation. Now you have it twice.
The NOTAR uses a combination of technologies to create anti-torque.
The primary thrust is created by air through a nozzle at the end of the tail. This has the same effect as a tail rotor - pushing air against the direction of rotation to counter the torque. In most helicopters the fan that creates this thrust is at the end of the tail boom, in the form of a traditional tail rotor or Fenestron. In the NOTAR, the fan is mounted inside the boom, in the intracostal area where tail boom attaches the main fuselage section. The pressure it creates is ejected through a nozzle at the end.
The NOTAR also takes advantage of the Coanda Effect created when the main rotor downwash flows past the tail boom. The shape of the boom creates an attraction to the airflow, and thus anti-torque force.
The fan is driven by the same drivetrain that powers the tail rotor in thr traditional Hughes or MD products, so the answer to your second question is 'YES'. You still have yaw control with no hamster.
Oops. Just read Mag's explanation. Now you have it twice.
HeloTeacher
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And as to the pusher T/R. I believe it is Piasecki that has an experimental design in development wherein the tailrotor is a pusher, high speed lift is derived from stub wings, and vanes aft of the tail-rotor/prop are used for anti-torgue. Supposed to compete with tilt-rotor technology.
HeloTeacher
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And as to the pusher T/R. I believe it is Piasecki that has an experimental design in development wherein the tailrotor is a pusher, high speed lift is derived from stub wings, and vanes aft of the tail-rotor/prop are used for anti-torgue. Supposed to compete with tilt-rotor technology.
CTD, wasn''t there one of the earlier ''compounds'' that had the swivelling tail rotor that provided pusher thrust, or was it a more recent drawing board venture? Oops! Maybe I''m just picturing the Lockheed Cheyenne with its tail rotor BESIDE its pusher propellor. Sexy idea, anyway, but, like the Cheyenne and the tilt-rotor, it would probably take much more than your average pilot to fly it.
CTD, wasn''t there one of the earlier ''compounds'' that had the swivelling tail rotor that provided pusher thrust, or was it a more recent drawing board venture? Oops! Maybe I''m just picturing the Lockheed Cheyenne with its tail rotor BESIDE its pusher propellor. Sexy idea, anyway, but, like the Cheyenne and the tilt-rotor, it would probably take much more than your average pilot to fly it.
Bladestrike
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Hey Teach, how are things?
I had a chance to see the Sikorsky ABC (Advanced Blade Concept) in the early eighties (or late seventies????). The idea behind the stubbies providing lift at high speed is requiring less rotor pitch for the lift vector, and with small turbofans for propulsion, you didn''t need much pitch for the "go fast" vector, so there was much less exposure to blade stall. Much like the Piasecki design. I think they were hitting nearly 300 knots, if not more. It was a coaxial design, one shaft through the other, with either blade cancelling out the negative tendacies of the other at high speed. I''m not sure what happened to it, but I thought it had a future. Sure looked cool.
I had a chance to see the Sikorsky ABC (Advanced Blade Concept) in the early eighties (or late seventies????). The idea behind the stubbies providing lift at high speed is requiring less rotor pitch for the lift vector, and with small turbofans for propulsion, you didn''t need much pitch for the "go fast" vector, so there was much less exposure to blade stall. Much like the Piasecki design. I think they were hitting nearly 300 knots, if not more. It was a coaxial design, one shaft through the other, with either blade cancelling out the negative tendacies of the other at high speed. I''m not sure what happened to it, but I thought it had a future. Sure looked cool.
