If engine anti-ice is activated and cockpit door gunner heater is on, by how much should the maximum Q available be reduced?

If engine anti-ice is activated and cockpit door gunner heater is on, by how much should the maximum Q available be reduced?

• A. -20%
• B. -5%
• C. -25%
• D. -30%

Answer: (C)

When you have engine anti-ice and the cockpit door gunner heater both on, the engine is carrying additional loads from bleed-air to anti-ice and from the heater to heat the gunner area. This extra demand reduces the power margin available to drive the rotor. The UH-60S power-management guidelines specify a 25 percent derate to the maximum rotor torque (Q) in this scenario, so you can safely use only 75% of the normal Q. That’s why the correct choice is a 25% reduction. The other percentages would not align with the documented derate for this combination of loads.

When you have engine anti-ice and the cockpit door gunner heater both on, the engine is carrying additional loads from bleed-air to anti-ice and from the heater to heat the gunner area. This extra demand reduces the power margin available to drive the rotor. The UH-60S power-management guidelines specify a 25 percent derate to the maximum rotor torque (Q) in this scenario, so you can safely use only 75% of the normal Q. That’s why the correct choice is a 25% reduction. The other percentages would not align with the documented derate for this combination of loads.