Bob's next bird

FlyNE said:
What's funny is that I thought the EXACT same thing when I saw this picture that Lenny had posted from Oshkosh.

http://www.leonardmack.com/oshkosh/daythree/img_1217.html

:yes: :D:D
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Can I, can I, please?

I would love to make just one flight in a Cobra. Not only some really cool armaments for when the neighbors act up, but that thing is way faster than most airplanes to be found on this board (Vne 222 kt, if I remember correctly). :yes:
 
RotaryWingBob said:
Can I, can I, please?

I would love to make just one flight in a Cobra. Not only some really cool armaments for when the neighbors act up, but that thing is way faster than most airplanes to be found on this board (Vne 222 kt, if I remember correctly). :yes:
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Sure! Knock yourself out. Now that you've sold the Archer, all you have to do is sell the R-22 and you should be able to pay for a couple of hours in the Cobra. ;)
 
bob im curioius how they pull off that kind of speed. i would think there would be retreating blade stall issues?
 
I was intrigued by this statement, "The Dauphin is a twin-turbine IFR-capable helicopter equipped with a four-axis autopilot" Lets see, pitch, roll, yaw, and......??? Can't be altitude as that is not an axis.
 
tonycondon said:
time scott, it controls time
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That is what I was thinking.

This must be the prototype

uncle-rico-time-machine.jpg

From Uncle Rico Technologies
 
tonycondon said:
bob im curioius how they pull off that kind of speed. i would think there would be retreating blade stall issues?
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I would agree, and I can only guess. There are a number of helicopters (all military) which can get near or over 200 kt. Most have tandem seating.

AH-64 197 kt
Ka-50 210 kt (coaxial rotors)
UH-60 194 kt

My guess is that the rotor tip speeds are less than generally used, which would reduce the effective relative tail wind of the retreating blade(s). I don't have a clue what the aerodynamic effects of that might be. I think I'll ask around...
 
smigaldi said:
I was intrigued by this statement, "The Dauphin is a twin-turbine IFR-capable helicopter equipped with a four-axis autopilot" Lets see, pitch, roll, yaw, and......??? Can't be altitude as that is not an axis.
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Helicopters have four primary flight controls:

Cyclic - controls both yaw and pitch
Collective - controls main rotor pitch
Pedals - control yaw
Throttle - controls rotor rpm
 
so they run really low rpms? i did quick math and for 300 rpms (isnt that about typical?) you would need something like a 11 ft radius blade to keep the tips below 220 knots.
 
tonycondon said:
so they run really low rpms? i did quick math and for 300 rpms (isnt that about typical?) you would need something like a 11 ft radius blade to keep the tips below 220 knots.
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You need a hobby...:D
 
FlyNE said:
You need a hobby...:D
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220 knots is 22000 feet per minute. the distance traveled by the tip in one revolution is just 2*pi*radius (Circumference) so:

300*2*pi*radius = 22000

pretty easy division
 
RotaryWingBob said:
Helicopters have four primary flight controls:

Cyclic - controls both yaw and pitch
Collective - controls main rotor pitch
Pedals - control yaw
Throttle - controls rotor rpm
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Ya but one of those is not an AXIS'. There are only three axis that anything in our spatial reality can travel through, pitch, roll, and yaw. Time as an axis of the 4th dimension is a mathematical model at this time. The engine power controls are not defined as an axis.

You know as well as in a HP fixed wing you have

Yoke which is similar to the Cyclic (controls both yaw and pitch), but controls pitch and roll

Prop control which like the Collective (controls main rotor pitch) controls the propeller pitch for RPM control

Rudder pedal like Pedals, control yaw

Throttle in the helo controls rotor rpm in the fixed wing control engine power for variable pitch or actual rpm in fixed pitch. Yet we do not call an autopilot in a fixed wing that has auto throttle capabilities an axis.

The author should have stated 3-axis autopilot with auto power control. If the autopilot companies are calling it an axis that just strikes me as marketing speak
 
smigaldi said:
Ya but one of those is not an AXIS'. There are only three axis that anything in our spatial reality can travel through, pitch, roll, and yaw. Time as an axis of the 4th dimension is a mathematical model at this time. The engine power controls are not defined as an axis.

You know as well as in a HP fixed wing you have

Yoke which is similar to the Cyclic (controls both yaw and pitch), but controls pitch and roll

Prop control which like the Collective (controls main rotor pitch) controls the propeller pitch for RPM control

Rudder pedal like Pedals, control yaw

Throttle in the helo controls rotor rpm in the fixed wing control engine power for variable pitch or actual rpm in fixed pitch. Yet we do not call an autopilot in a fixed wing that has auto throttle capabilities an axis.

The author should have stated 3-axis autopilot with auto power control. If the autopilot companies are calling it an axis that just strikes me as marketing speak
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I don't agree that the yoke (gawd I hate yokes) is a single flight control. It operates two separate flight controls. The cyclic, on the other hand is a single flight control -- it simply tilts the rotor disk in whatever direction the pilot wants it to go...

But I do agree with your point about "axis".

Also, the cyclic has nothing to do with yaw.
 
RotaryWingBob said:
Also, the cyclic has nothing to do with yaw.
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I am just going with what you said

RotaryWingBob said:
Helicopters have four primary flight controls:

Cyclic - controls both yaw and pitch
Collective - controls main rotor pitch
Pedals - control yaw
Throttle - controls rotor rpm
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;);)BFR time ;);) ????

You meant roll, right?
 
I think that there's a difference between an axis of control and an axis of motion. What I mean by this is that any flight control can be between 0% and 100% of deflection. I guess the best thing to relate it to would be a joystick on a computer or a transmitter for RC planes. When you set up a joystick in windows, there is one axis for each non-binary control. Any control that has a range is an axis itself.

If you ask me, "axis" does not refer to the one of three axes than an aircraft can move about, but the axis of the control itself.

Just my opinion.
 
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