Exhaust Section, Reverse Thrust

What happens when exhaust velocity is greater than forward speed?

• Thrust

• Deceleration

• Engine overheating

• Stress cracking from rapid cooling

What happens at the exhaust of a converging/diverging ducted exhaust?

• Pressure decreases, velocity increases

• Pressure increases, velocity increases

• Pressure increases, velocity decreases

• Pressure decreases, velocity decreases

The velocity of the gases in the exhaust unit is held to:

• Mach 0.5 to minimize turbulence

• Mach 0.75 to optimize the pressure distribution

• Mach 0.85 to maximize thrust

• Mach 1 to maximize acceleration

The exhaust cone:

• straightens the gas flow before it goes into the turbine assembly

• prevents the hot gases flowing across the rear turbine face

• increases the velocity of the gases

• decreases the pressure of the gas

What exhaust system does a high-performance military jet use?

• Convergent-divergent

• Convergent

• Divergent

• Divergent-convergent

How do designers reduce noise produced by turbine engines?

• Reduce exhaust gas velocity

• Increase Exhaust gas temp

• Use a convergent divergent duct

• Increase exhaust velocity

Use of reverse thrust below the recommended speed may cause:

• over stressing of the gear oleos.

• ingestion of the exhaust gases and foreign objects.

• more fuel to be provided to the burners.

• the TGT limit to be exceeded, in which case the reverse thrust lever will return to the forward thrust position.

Before reverse thrust can be selected, the forward thrust lever must be:

• pulled back to idle power.

• positioned to reverse minimum power.

• put back to the reverser deploy position.

• positioned to reverse maximum power.

A reverse thrust warning light illuminates:

• only when the reverser doors are fully deployed in the reverse thrust position.

• when the reverser doors are stowed in the forward thrust position.

• when the reverser doors are not stowed in the forward thrust position.

• whenever reverse thrust is selected.

Is reverse thrust more efficient at:

• High Speeds

• Low Speeds

• Is equally efficient at all speeds

• Is more efficient when the aircraft is flying upside down