Mailinglist Archive: opensuse-programming (118 mails)
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Re: [suse-programming-e] Programming standards!
- From: Jerry Feldman <gaf@xxxxxxx>
- Date: Wed, 20 Apr 2005 08:30:11 -0400
- Message-id: <200504200830.11746.gaf@xxxxxxx>
On Wednesday 20 April 2005 5:42 am, Colin Carter wrote:
> This is interesting. I know about gyroscopes, but hadn't thought about
> it in the sense of controlling helicopters. To move forward I imagine
> that the rotor plane would have to lower itself at the front (true?), in
> which case the force (as you mentioned at 9o deg) would have to cause a
> little roll of the fuselage, albeit very slight. Is this true?
Not really. The rotor blades are hinged at the rotor mast. A downward force
is exerted aerodynamically to the rotor blades 90 degrees in advance of the
rotor plane. This causes the rotor blades to tilt forward. Try this with
toy gyroscope.
> I hadn't thought about that; I guess it would be much like one racing
> yacht "stealing" the breeze from another.
>
> I don't think I'd be very good in a helicopter: I get sea sick; not at
> all if the vessel is ploughing through very rough water at speed - rather
> when the boat has a very gentle sway/roll in almost calm waters.
There are 5 controls in a helicopter that a pilot must operate
simultaneously:
1. The cyclic - This is the stick and controls the tilt of the rotor blades
and the helicopter. Similar to the stick in a fixed wing, and in forward
flight nearly identical.
2. The collective. This makes the helicopter go up or down.
3. The throttle (on the collective). When you pull pitch, you need to
simultaneously give it more throttle.
4, 5. The anti-torque rotor pedals. Anytime a change is made with the
throttle, you need to compensate for the additional or reduced torque
caused by the throttle changes. Additionally, the pedals themself require
more or less throttle. Much like a feedback loop.
There are generally 3 kinds of rotor systems:
1. Rigid - not used very much. This was a goal that was finally achieved by
Lockheed in the 1970s.
2. semi-rigid - Mainly Bell Helicopters - 2 blades that teeter on the rotor
mast. Each blade can feather - increase of decrease its angle of attack
independently of the other).
3. Fully articulated. Most helicopters use this. Each blade is hinged to the
rotor mast where it can feather, float up or down, and even move forward or
backward independently of the others. (The angle between the blades can
vary). One interesting anomaly is that if the system is not tuned
correctly, the rotor system can cause vibration when in contact wit the
ground and self destruct.
In any case, the mission of all helicopters is self destruction.
--
Jerry Feldman <gaf@xxxxxxx>
Boston Linux and Unix user group
http://www.blu.org PGP key id:C5061EA9
PGP Key fingerprint:053C 73EC 3AC1 5C44 3E14 9245 FB00 3ED5 C506 1EA9
> This is interesting. I know about gyroscopes, but hadn't thought about
> it in the sense of controlling helicopters. To move forward I imagine
> that the rotor plane would have to lower itself at the front (true?), in
> which case the force (as you mentioned at 9o deg) would have to cause a
> little roll of the fuselage, albeit very slight. Is this true?
Not really. The rotor blades are hinged at the rotor mast. A downward force
is exerted aerodynamically to the rotor blades 90 degrees in advance of the
rotor plane. This causes the rotor blades to tilt forward. Try this with
toy gyroscope.
> I hadn't thought about that; I guess it would be much like one racing
> yacht "stealing" the breeze from another.
>
> I don't think I'd be very good in a helicopter: I get sea sick; not at
> all if the vessel is ploughing through very rough water at speed - rather
> when the boat has a very gentle sway/roll in almost calm waters.
There are 5 controls in a helicopter that a pilot must operate
simultaneously:
1. The cyclic - This is the stick and controls the tilt of the rotor blades
and the helicopter. Similar to the stick in a fixed wing, and in forward
flight nearly identical.
2. The collective. This makes the helicopter go up or down.
3. The throttle (on the collective). When you pull pitch, you need to
simultaneously give it more throttle.
4, 5. The anti-torque rotor pedals. Anytime a change is made with the
throttle, you need to compensate for the additional or reduced torque
caused by the throttle changes. Additionally, the pedals themself require
more or less throttle. Much like a feedback loop.
There are generally 3 kinds of rotor systems:
1. Rigid - not used very much. This was a goal that was finally achieved by
Lockheed in the 1970s.
2. semi-rigid - Mainly Bell Helicopters - 2 blades that teeter on the rotor
mast. Each blade can feather - increase of decrease its angle of attack
independently of the other).
3. Fully articulated. Most helicopters use this. Each blade is hinged to the
rotor mast where it can feather, float up or down, and even move forward or
backward independently of the others. (The angle between the blades can
vary). One interesting anomaly is that if the system is not tuned
correctly, the rotor system can cause vibration when in contact wit the
ground and self destruct.
In any case, the mission of all helicopters is self destruction.
--
Jerry Feldman <gaf@xxxxxxx>
Boston Linux and Unix user group
http://www.blu.org PGP key id:C5061EA9
PGP Key fingerprint:053C 73EC 3AC1 5C44 3E14 9245 FB00 3ED5 C506 1EA9
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