Vno: 169 kts - Max structural cruising speed, high end of green arc
Vne: 202 kts - Never exceed, red line
Vr: 75 kts - Not less than Vmc*1.05, must allow acceleration to V2 at 35' at end of runway
Vlof: 75-77 kts - At least Vmc + 5 kts
V1: Decision Speed - Engine failure below V1 shall abort takeoff, above V1 shall be continued
V2: Takeoff Safety Speed - Approximately Vxse speed, should be maintained until 1000' AGL unless specified otherwise
Vfs: Final Segment Climb Speed - Best one-engine inoperative rate of climb speed, clean configuration, thrust reduced to MCT(Maximum Continuous)
Net Take-off Flight Path (NTOFP) For Engine Failure: 4 segments
Weight
Max Ramp Weight: 3816
Max Takeoff Weight: 3800
Max Landing: 3800
Max Baggage: 200
Max Zero Fuel:N/A
Engine
2700 rpm
180 HP
Full Throttle(MP)
Max CHT: 500
Min CHT: 200
POH recommends CHT: 350 - 435
Max Oil Temp: 245
115 PSI(Oil Pressure), 25 PSI minimum
Propeller
74'' Max
72'' Min
Fuel
Total: 110 Gallon
Usable:108
Unusable: 2
Minimum Grade: 100, 100LL
Oil
Max: 8 qts
Minimum(UND): 6 qts
Minimum safe(POH): 2 qts
POH Recommend: 4-8 qts
Electrical
Alternator: Max load on ground: 60 amps, Max in air: 65 amps
Main Battery: 25-32 Volts
Emergency Battery: 20-32V, Minimum for flight: 23.3V
Flight Load
Positive: 3.8G(Flaps up)
Positive: 2.0G(Flaps down)
Negative: -1.5G
Acronyms
Critical Engine Concept:
PAST
P-factor: Yaw
A-Accelerated Slipstream: Roll
S-Spiraling Slipstream: Yaw *Only when the right engine fails
T-Torque: Roll
P-factor Yaw
Descending blades, typically with a higher angle of attack, produce more lift.
Left engine critical in conventional twins because the right engine has a longer torque arm.
No engine critical in counter-rotating twins. Both torque arms the same length.
A-Accelerated Slipstream: Roll
Results from P-factor, higher angle of attack blades produce more prop wash.
Left engine critical in conventional twins.
No engine critical in counter-rotating twins.
Spiraling Slipstream: yaw
Slipstream hitting the vertical stabilizer.
In conventional twins:
Left engine prop wash will counteract asymmetrical thrust from right engine failure.
Right engine prop wash will not do anything.
Left engine critical because left engine failure consequence is more severe, due to no counteract thurst from the left engine.
In counter-rotating twins:
Both engines help to counteract asymmetrical thrust in an event of engine failure, thus no critical engine in counter-rotating twins.
T-Torque: Roll
Opposite and equal reaction to every action. Newton's Law Law of motion.
In conventional twins:
Each engine rolls the plane to the left by torque. However, a right engine failure causes the plane to roll right due to accelerated slipstream; a left engine failure causes the plane to roll left more. Thus, the left engine is critical.
In counter-rotating twins:
No engine is critical. Both can offset the accelerated slipstream.
Prop Forward: Speeder spring tension increase -> Flyweights fall in -> Lowering pilot valve -> Oil goes into the prop hub-> Low pitch - fine pitch - blade angle decrease - high rpm -> Fly weights return to equalibrium -> Raise pilot valve -> Oil flow from oil sump to prop hub stops -> Rpm remain high
Prop Rearward: High pitch - small blade angle - course pitch - low rpm - feather
Feathering time:
Without accumulator: 6s
With accumulator: 10-17s
Unfeathering accumulator:
Contain nitrogen and oil pressure(90-100psi)
Assist in unfeathering the propeller without undue stress to start
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