Mmmm?
In the rainbow aircraft advert on the backpage of one of the Microflight mags it states that the Cheetah as Step-on-the-ball as standard equipment - what is that? Artificial Horizon maybe?
Step-on-the-ball?
-
DarkHelmet
- Toooooo Thousand
- Posts: 2046
- Joined: Mon May 23, 2005 10:12 am
- Location: Jukskei Park - Randburg
-
RV4ker (RIP)
- The Big Four K
- Posts: 5386
- Joined: Sun May 22, 2005 7:48 pm
- Location: The Coves & FAVB
When the ball is out to the right on the indicator, step on right rudder to correct back to centre and vice versa for left, from there the "informal" name of Step on the Ball - me thinks 
And this whole argument goes doen the pipe when trying to land in hectic crosswind or flying in turbulance - stuff the ball, just get the aerie down safely.
And this whole argument goes doen the pipe when trying to land in hectic crosswind or flying in turbulance - stuff the ball, just get the aerie down safely.-
RV4ker (RIP)
- The Big Four K
- Posts: 5386
- Joined: Sun May 22, 2005 7:48 pm
- Location: The Coves & FAVB
-
RV4ker (RIP)
- The Big Four K
- Posts: 5386
- Joined: Sun May 22, 2005 7:48 pm
- Location: The Coves & FAVB
RTFQ? 
Sorry guys. I don't do mornings well.
DH
The step on the ball is a slip indicator which is yaw axis. Slip Indicators
A "slip" or "skid" or "bank" indicator provides an economic method of determining the lateral differential movement when banking or turning in an aircraft. The bank or slip indicator consists of a curved glass tube filled with a damping liquid in which a small ball rolls. When the craft is horizontal, the ball is located in the lowest part of the tube; as the craft banks, gravity holds the ball at the lowest point as the tube rotates from side to side. The tube can be calibrated to show the angle of banking.
Sorry guys. I don't do mornings well.
DH
The step on the ball is a slip indicator which is yaw axis. Slip Indicators
A "slip" or "skid" or "bank" indicator provides an economic method of determining the lateral differential movement when banking or turning in an aircraft. The bank or slip indicator consists of a curved glass tube filled with a damping liquid in which a small ball rolls. When the craft is horizontal, the ball is located in the lowest part of the tube; as the craft banks, gravity holds the ball at the lowest point as the tube rotates from side to side. The tube can be calibrated to show the angle of banking.
BTW GR8-Dad, once you haev mastered this instument in the Cessna you are going to climb into the Challenger and forget all about it and try and master the string. A lot more sensitive and opposite to the ball, i.e. if it is facing left, press right. Could be confusing at first.GR8-DAD wrote:BTW - I got his "step on the ball" tender patch on my skull - that is where my instructor moers me at least 5x during a lesson
:DGreg Perkins
I see a lotta moering still to come..Morpheus wrote:.. mastered this instument in the Cessna you are going to climb into the Challenger and forget all about it and try and master the string. A lot more sensitive and opposite to the ball, i.e. if it is facing left, press right. Could be confusing at first.
-
RV4ker (RIP)
- The Big Four K
- Posts: 5386
- Joined: Sun May 22, 2005 7:48 pm
- Location: The Coves & FAVB
-
Thunderboy
- Pilot in Command
- Posts: 775
- Joined: Fri Nov 04, 2005 2:51 pm
- Location: CrossWinds
- Contact:
OK my exam tomorrow night includes this
Deffinatley advertising it for the cheetah which being 3 axis has a rudder.
Basically in turns when banking your tail slides, slips or saggs inside the flight path. This happens beacuse of the one aileron being up and the other down. On the down aileron there is more lift but this causes more induced drag. While the a/c does roll in the direction you want to turn because of the differing drag forces of the up and down ailerons it also wants to yaw in the opposite direction of the roll because of the different drag forces (known as adverse aileron yaw) You see this by you turn and slip indicator and step on the ball which then helps the plane yaw in the correct direction
In your 3 axis microlights you use your rudder a lot more than you would say in a cessna. Some of the bigger planes advertise no adverse aileron yaw which means you hardly use rudder except maybe a bit on landings. You also need the rudder to combat a slipstream effect which is from the flow of air from the propeller pushig against 1 side of the tail/rudder depending on prop direction in s&l flight which would also show on the ball.
Deffinatley advertising it for the cheetah which being 3 axis has a rudder.
Basically in turns when banking your tail slides, slips or saggs inside the flight path. This happens beacuse of the one aileron being up and the other down. On the down aileron there is more lift but this causes more induced drag. While the a/c does roll in the direction you want to turn because of the differing drag forces of the up and down ailerons it also wants to yaw in the opposite direction of the roll because of the different drag forces (known as adverse aileron yaw) You see this by you turn and slip indicator and step on the ball which then helps the plane yaw in the correct direction
In your 3 axis microlights you use your rudder a lot more than you would say in a cessna. Some of the bigger planes advertise no adverse aileron yaw which means you hardly use rudder except maybe a bit on landings. You also need the rudder to combat a slipstream effect which is from the flow of air from the propeller pushig against 1 side of the tail/rudder depending on prop direction in s&l flight which would also show on the ball.
Thanks for the concise description and good luck with the exam.
Cessna's tend to oversome the level of yaw by using a larger tail surface and differential ailerons, i.e. the downward movement of the aileron is smaller than the upward movement. Since it is the downward movement of the aileron that increases the drag, by reducing this movement you reduce the drag and thus the yaw. The roll is still maintained by increasing the upwards movement of the opposite aileron.
Cessna's tend to oversome the level of yaw by using a larger tail surface and differential ailerons, i.e. the downward movement of the aileron is smaller than the upward movement. Since it is the downward movement of the aileron that increases the drag, by reducing this movement you reduce the drag and thus the yaw. The roll is still maintained by increasing the upwards movement of the opposite aileron.
Greg Perkins
Who is online
Users browsing this forum: No registered users and 10 guests