×
Welcome to the CPL Aerodynamics question and answer forum. Please feel free to post your questions but more importantly also suggest answers for your forum colleagues. Bob himself or one of the other tutors will get to your question as soon as we can.
Slip & Skid
Chao
Topic Author
Chao created the topic: Slip & Skid
Hi Bob and Richard,
Just enquire about a definition in your book, which is shown in an attachment.
"The turn is balanced when the rate of yaw exactly equals the rate of pitch." Could you explain it for me, please? Because at first I was confused by slip and skid, i did lots of research, and What I have learned about slip/skid is that slip is where the angle of bank is too great for the rate of turn, skid is where the rate of turn is too great for the angel of bank.
Now i am confused by the definition in book, especially the rate of pitch. Does it have something to do with slip&skid? I thought it(balanced turn or coordinated turn) has something to do with the angle of bank and rate of turn.
As far as the pitch, what I know is that pulling back on the control column is to increase the angle of attack and to keep the altitude.
There are only two types of motion occurring during a level turn - pitch and yaw. Once the aircraft has been banked into the turn the ailerons are used to maintain a constant bank, so there is no roll occurring. During the turn it is necessary to apply a back pressure on the control column and that means that the aircraft is constantly pitching during the turn (think of the extreme case of 90° of bank - not possible in practice). In that case, the only motion occurring would be pitch - it would in fact be a horizontal loop. The aircraft's designed directional stability along with any rudder input produces the yaw. In a correctly balanced level turn, for any given bank angle, the amount of back pressure (rate of pitch) and the amount of rudder (rate of yaw) will keep the skid ball centered. Whatever bank angle you choose will automatically require a particular degree of back pressure (rate of pitch), to produce a particular rate of turn.
It is true that the back pressure increases the angle of attack to produce the extra lift necessary during the turn, but to maintain a constant increased angle of attack with a constantly changing direction of relative airflow during the turn, the aircraft must be constantly pitching as it proceeds around the turn.
