PRIVATE - PERFORMANCE

State and define all the airspeeds for your aircraft.
(A Cessna 152 is the aircraft being referenced)
Vso 35, Vs 40, Vr 50, Vx 55, Vy 67, Vg 60, Vfe 85, Va 93-104, Vno 111, Vne 149.

Does Vy and Vx ever change?

Yes they do. When density altitude increases, Vy goes down and Vx goes up.

Can the aircraft stall at 80 KIAS? 

Yes, if you were to increase the load factor on the aircraft enough, it would stall at that speed.

What is load factor?
Load factor is the result of the lift being generated by the wings divided by the weight of the aircraft.

How much load factor can your aircraft receive?
This all depends on the certification category of your airplane. A normal category airplane can handle -1.52 to +3.8 Gs.

What is the relationship between angle of bank, load factor, and stall speed?
If the airplane is banked and altitude is held the load factor will increase, which increases stall speed.

How would you recover from a spin?
The usual procedure used to recover from a spin is as follows. Power to idle, aileron neutral, rudder in the opposite direction of the yaw, and when the rotation stops push forward on the elevator. Always refer to your POH for specific instructions.

Explain maneuvering speed? 
This is the maximum speed that you can apply full abrupt control pressure without exceeding the structural load limitation of the aircraft.

What is indicated airspeed?
This is the speed read directly off the airspeed indicator.

What is calibrated airspeed?
This is indicated airspeed corrected for position and installation errors.

What are position and installation errors?
Based on different pitch settings, the airflow patterns in and around the pitot tube will produce inaccurate airspeed readings.

How do you determine calibrated airspeed?
You would need to reference your POHs' performance section for this information.

What is true airspeed?
This is the actual speed the aircraft is traveling in relationship to the surrounding air mass. Also, it is calibrated airspeed corrected for nonstandard temperature and non standard pressure.

If calibrated airspeed is 100 knots, the temperature is 15° Celsius, indicated altitude is 5,500, and the altimeter setting is 30.42, what is the true airspeed?
True airspeed is 109.

What is ground speed?
This is the speed of the aircraft across the ground. It is true airspeed corrected for wind.
Make sure you can work through all the steps required to go from indicated airspeed to groundspeed.

What is indicated altitude?
This is the altitude read directly off the altimeter when the appropriate altimeter setting is used. This altitude is also the aircrafts' height above MSL.

What is pressure altitude?
This is the altitude above the standard datum plane, or in other words, pressure altitude is indicated altitude corrected for nonstandard pressure.

What is density altitude?
Density altitude is pressure altitude corrected for nonstandard temperature. This is the "performance" altitude, meaning that the aircraft will perform as if it were at this altitude, even though the indicated altitude is different.

What is the density altitude if you are cruising at 6,500 feet indicated, the outside air temperature is 15° Celsius, and the altimeter setting is 29.42"?
The density altitude is about 8,500' feet.

What is a service ceiling?
A service ceiling is the density altitude at which the aircraft will climb at 100 feet per minute or less while using the best rate of climb.

What is an absolute ceiling?
An absolute ceiling is the maximum density altitude the aircraft is capable of flying at.

Determine takeoff distance for your aircraft using the following conditions.
Maximum weight, runway elevation 3,500 feet, altimeter 29.42, temperature 25' Celsius, and a headwind of 9 knots. (Reference aircraft is a Cessna 152)
A ground roll distance of 1030.5 feet and 50 foot obstacle clearance distance of 1948.5 feet is required to depart.

In the following problem you have calculated a ground roll distance needed to depart legally. Would you takeoff if you had exactly that amount of runway?
No, you should not. Consider that the takeoff distance was calculated using a new airplane with a new engine. Also the company used a perfect runway, or close to it. And they used a very competent test pilot. I recommend that you add your takeoff distance to your landing distance, and use that as the safe distance for takeoff and landing.

When and how do you lean the mixture?
(The airplane in reference is a Cessna 152)
You will lean the mixture anytime the aircraft is operating above a density altitude of 3,000. To lean the mixture, you will rotate the mixture counter clockwise for a peak RPM indication.

Would you ever lean for takeoff?
Yes, you must lean the mixture anytime operating above 3000 feet density altitude.

How do you determine cruising true airspeed?
When referencing the cruise performance chart in your POH you will notice rows of different altitudes, rows of different power settings, and columns of different temperatures. First find the cruising altitude. For this example we will use a cruise altitude of 4,500, so just use 4,000. Next we choose the power setting. Personally I like operating on the performance side as compared to the economical side so I will choose 2450, but this is up to you whether you want to conserve fuel or not. And lastly we will need to find the temperature. For this information you will need to reference a winds and temperature aloft forecast, and interpolate between 3,000 and 6,000 feet. Let's say the temperature is 16' Celsius, which would place us between standard and 20' Celsius above standard. The result is our speed would be about 104 KTAS and our fuel burn would be about 6.2 GPH.

In the previous question, would you actually be able to achieve 104KTAS?
You would only be able to go that fast if your airplane is equipped with speed fairings. Reference the note section of the cruise performance chart.

What is standard temperature at 4,500?
The standard temperature at 4,500 is 6 degrees Celsius. This is determined by subtracting 2 degrees from the standard temperature of 15 degrees for each 1,000 foot rise in altitude.

On the cruise performance chart what is % BHP used for?
BHP is used for determining range and endurance on the following pages beyond the cruise performance chart.

What is basic empty weight?
This is the weight of the aircraft without fuel, baggage, and people.

Where is the basic empty weight found?
This weight information can be found in the aircraft, usually located within the POH.

What is maximum useful load?
Useful load is the difference between the maximum ramp weight and the basic empty weight.

What happens when you exceed the manufacturers' weight limitations?
The performance of the airplane is unpredictable. You may not be able to get airborne, climb, or come to a stop in the desired distance during landing.

What is the calculation for determining the center of gravity?
Weight multiplied by arm equals moment. Total moment divided by total weight equals center of gravity.

What is the definition of center of gravity?
CG is the point where the aircraft will balance, or in other words the point at which the aircraft rotates around.

What happens to cruise airspeed with an aft CG?
Cruise airspeed increases.

Explain how drag changes as you move the CG aft.
When
the CG is moved aft, the horizontal stabilizer will produce less downward force, which will result in wings needing less lift hold the plane in level flight. With less lift there will be a reduction in induced drag, hence the reason for an increased airspeed.

What happens to stability with an aft CG?
The airplane is less stable.

What happens to stall speed with an aft CG?
Stall speed will decrease.

What would you expect of an aircraft that is loaded beyond its forward CG limits?
Besides the lack of stability, during landing you may not have enough elevator authority to transition to a nose high landing attitude.

What would you expect of an aircraft that is loaded beyond its aft CG limits?
The elevator controls may not be able to provide enough force to recover from a stall/spin.

What is the angle of incidence?
This is the angle formed between the longitudinal axis and chord line of the wings and horizontal stabilizer.

What holds the nose up?
The negative angle of incidence of the horizontal stabilizer holds the nose up.

What is dihedral?
This is the angle formed between the lateral axis and the line between the wing root to wing tip. The purpose of dihedral is to create lateral stability.

What is wing wash out?
This is the decreasing angle of incidence from wing root to wing tip. The purpose of wing wash out is to maintain roll stability when entering a stall by allowing airflow over the ailerons despite the stalled condition occurring on wing roots.

What is adverse yaw?
This is a yaw in the opposite direction of a roll when turning without rudder. For example, when turning to the right, the left aileron moves downwards creating a higher angle of attack which produces more lift in order to raise the wing. But when more lift is created more drag is also created. Since the left wing has more drag, the aircraft will yaw momentarily to the left during a right turn without rudder.


What are the four turning tendencies, and their definitions?
Gyroscopic precession, when a force is applied to a spinning disc, the force will be exerted 90 degrees ahead of its rotation causing a yaw. Gyroscopic precession will cause a yaw to the right during a climb, and cause a yaw to the left during a descent. Asymmetrical thrust, when climbing the descending blade will have a greater angle of attack which will produce more thrust than the ascending blade causing a yaw to the left. During a descent, the yaw will be to the right. Torque effect, due to the direction of the engines' rotation, the airplane will attempt to roll in the opposite direction, which for a Cessna 152 will be to the left. And spiraling slipstream, the rotating airflow around the fuselage will strike the left side of the vertical stabilizer causing a yaw to the left.