Re: What happens during rotation at takeoff?

-----Original Message-----
From: Erik Hofman [mailto:[email protected]] 
Sent: Thursday, November 09, 2017 3:30 AM
To: [email protected]
Subject: Re: [Flightgear-flightmodel] What happens during rotation at
takeoff?

On 11/09/2017 04:45 AM, Ivan Soleimanipour wrote:
> Hi,
> 
> I'm developing my own simulator so this is a generic simulation 
> question I'm hoping the collective experience here can shed some light 
> on.
> 
> It seems so simple. You pull on the stick, rotate and you take off.
> 
> If you analyze the situation in the craft frame with origin for 
> moments at the rear wheels it's straighforward. The elevator pushes 
> down and that rotates the craft around the wheels and the CG rises.

>>I think you will need to analyze it as if the aircraft is already flying.
The aircraft rotates around it's aerodynamic reference point (around 25%
wingspan) when >>you pull the yoke (or stick). The only difference is that
the movement is restricted by the landing gear which will generate a counter
rotational force.

>>Erik


Negative. The aircraft rotates about the center of gravity when in the air.
On the ground, such as during a takeoff or landing, it rotates about the
contact point. 

Bill


------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot