Pitch control- what the heck is this??? Help
02-02-2009 | 12:56 AM
#51
RE: Pitch control- what the heck is this??? Help
Tarus, some folks have suggested that a canard is not a case of the stabilizer being on the front of the model. Instead mathematically and from various stability standpoints it is actually a conventional layout that uses a very small main wing with a really BIG stabilizer.
Note that it is possible to calculate the neutral point and stability margin for a canard using the website calculators that show a conventional layout if you just stick in the area of the canard surface in the main wing area and the rear wing into the stabilizer area.
Note that it is possible to calculate the neutral point and stability margin for a canard using the website calculators that show a conventional layout if you just stick in the area of the canard surface in the main wing area and the rear wing into the stabilizer area.
]
02-03-2009 | 07:08 AM
#54
Thread Starter
Member
Joined: Sep 2007
Posts: 84
Likes: 0
Received 0 Likes
on
0 Posts
From: Geneva, , SWITZERLAND
RE: Pitch control- what the heck is this??? Help
Aha! Here my book actually helps me- are you talking about the stick fixed neutral point or the stick free neutral point? In other words the neutral point where there is a fly-by-wire configuration or the mechanical configuration (stick free)?
The stick fixed neutral point of an airplane is nothing but the aerodynamic center of that airplane where about which the airplane is neutrally stable in pitch. The formula for calculating the static margin of an airplane, and consequently the neutral point location, Lnp, is in the attachment. I would assume that this neutral point would be much close to the center of gravity and the static margin would be smaller in canard designs than of conventional designs? The only advantage of canard deswigns would be to put the wing into the stabs vortex and make it more efficient and also to get rid of the tail in roder to put up large propellers or other equipment?
Can someone explain to me why during ground effect it is BAD that the wing produces less downwash and the stab therefore gets less of it, and the neutral point thus moves back? How come it is GOOD when you put a wing in front of a wing so that the rear wing produces less downwash? How does that work? Is downwash GOOD? And if it is, how come piltos try to avoid it when following other aircraft so as that they do not get into turbulent flow?
Lafayette.
The stick fixed neutral point of an airplane is nothing but the aerodynamic center of that airplane where about which the airplane is neutrally stable in pitch. The formula for calculating the static margin of an airplane, and consequently the neutral point location, Lnp, is in the attachment. I would assume that this neutral point would be much close to the center of gravity and the static margin would be smaller in canard designs than of conventional designs? The only advantage of canard deswigns would be to put the wing into the stabs vortex and make it more efficient and also to get rid of the tail in roder to put up large propellers or other equipment?
Can someone explain to me why during ground effect it is BAD that the wing produces less downwash and the stab therefore gets less of it, and the neutral point thus moves back? How come it is GOOD when you put a wing in front of a wing so that the rear wing produces less downwash? How does that work? Is downwash GOOD? And if it is, how come piltos try to avoid it when following other aircraft so as that they do not get into turbulent flow?
Lafayette.
