M15.7 Exhaust And Thrust Reverser Flashcards
What does the exhaust cone do
Prevents reverse flow into the hub
Common exhaust nozzle advantage
Reduces the very high exhaust gas velocities
Disadvantage of common exhaust nozzle
Increased weight
Convergent exhaust nozzle max pressure ratio
2:1
What type of exhaust is used on aircraft that fly faster than the speed of sound
C-D exhaust convergent-Divergent
Unit used to express noise
Effective perceived noise decibel (EPNdB)
What does EPNdB take into account
- Pitch
- Duration
- Pressure
EPNdB
Effective Perceived Noise deciBel
Smaller eddies can cause noise in what frequency
Very high
At what bypass ratio is the jet noise so low the internal noise becomes available
5:1
Thrust reverse deflection angle
45 to 60 degrees
Types of thrust reversers
- Clam shell
- Bucket
- Fan Reverser (Translating sleeve)
- Pivoting door
When are reversers most effective
Shortly after landing (high speeds)
Adverse effects of thrust reverser
- FOD
- Decreased braking
- High EGT
- Stall danger
Thrust reverse main subsystems
- Control
- Actuation
- Airflow Deflection
What protects the reverse thrust control system
Air Ground Logic
Advantage of using the radio altimeter for reverse control
On short runways the thrust reverse can be deployed less than 10ft
Thrust reverser interlock purpose
Engine power can only be increased once the reverser is fully deployed
What ensures reverse door stowage
- Reverse door latch
- Internal actuator locks
Thrust reverse indications
Amber - Reverse unlock
Green - Fully deployed
What can actuate thrust reversers
Hydraulic or pneumatically
What slows the translating cowl when close to fully deployed
Feedback mechanism
Reverser deactivation methods
- Pneumatically
- Electric
- Mechanical
Which mechanical thrust reverser deactivation visually shows lockout condition
Red signal plates
