Factors the determine critical engine
PAST
P-Factor
Accelerated Slipstream
Spiraling Slipstream
Torque
Explain how P-Factor effects critical engine
Downward turning blade (right/farther away) if producing more thrust (yawing moment)
Explain how Accelerated Slipstream effects critical engine
The air being forced over the wing by the operating engine creates extra lift (rolling moment)
Explain how Spiraling Slipstream effects critical engine
Loss of air from the left engine (out) impacts rudder control (less effective rudder)
Explain how Torque effects critical engine
Torque tries to roll the airplane in the opposite direction of the propeller’s rotation. If the left engine fails, torque tries to roll the aircraft to the left, making it more difficult to raise the dead engine.
How does the manufacturer determine VMC
COMBATS
Critical engine failed and windmilling
Operating engine at maximum takeoff power
Most unfavorable weight
Bank of no more than 5 degrees
Aft center of gravity
Takeoff configuration (gear up, flaps up)
Standard temperature and pressure.
What FAR part governs multi-engine aircraft certification?
FAR Part 23
What percentage of performance is lost after losing one engine on the B95A or D95A?
80%
Why does the D95A not have a single engine climb requirement for certification?
- MTOW < 6,000
- Vso < 61kt
- Certificated before 12/30/2016
What 3 drag factors cause a significant loss in performance with a failed engine?
- Full Flaps
- Windmilling Propeller
- Gear Extended
Define Absolute Ceiling
Maximum density altitude where climb = 0 ft/min @ max gross weight, clean configuration, max continuous power.
Where VX = VY
Define Service Ceiling
Maximum density altitude where Vy will produce climb of 100 ft/min with both engines at max continuous power.
Define Single Engine Service Ceiling
Maximum density altitude with climb of 50 ft/min, one engine operating at max continuous power and inoperative engine’s prop feathered.
Define Single Engine Absolute Ceiling
Maximum density altitude where climb = 0 ft/min on a single engine
Define VMC
Calibrated Air Speed, where following a sudden loss of critical thrust, it’s possible to maintain directional control.
Which FAR governs VMC definition?
- Previoously: FAR 23.149
- Recent: FAR 23.2135(c)
What is the “critical” engine?
The engine that if lost, has the most adverse effects on performance and handeling.
How would you overcome side slip after losing an engine in-flight?
- Bank towards the operative engine (raise the dead)
- Rudder toward operative engine (dead foot, dead engine)
What are the warning signs you’re gettign close to VMC?
- Loss of directional control
- Stall warning or buffeting of controls
- A rapid decay of control effectiveness
What is the process to recover from VMC?
- Simultaneous Pitch down and Reduce power on the operative engine.
- At blue line (VYSE) begin to release forward pressure on the yolk and pitch up.
List some conditions where stalls occur most.
- IMC
- Un-commanded autopilot disconnect
- Low Altitude
- Go-Around
What additional conditions effect a stall for multi-engine airplanes?
- Asymetric Thrust
- More weight on wings
Define Accelerate Stop Distance
Runway length required to accelerate to VR or VLOF, experiance an engine failure, and bring the airplane to a complete stop.
Define Accelerate Go Distance
The horizontal distance required to takeoff and climb to 50’, assuming engine failure at VR or VLOF
