Environmental Control System

Question 1

What temperature range can the system supply for heating/air-conditioning?

Answer 1

2-71C

Question 2

AIR SOURCE ECS/START switch and its function in the ECS system.

Answer 2

The bleed-air portion of the ECS may receive air from the engines or APU. In the ENG position, engine bleed air is selected as the air source. In APU, bleed air is used as the air source. If the APU is operating, it will provide bleed air regardless of switch position.

Question 3

Tq loss vs. ECS Switch position.

Answer 3

With the ECS on and the FLOW switch in NORM, maximum torque available is reduced by 4 percent per engine and fuel flow to each engine will increase by approximately 8 pounds per hour. With the TEMP rotary switch in HOT and OAT below 15 °C, maximum torque available is reduced by 5 percent per engine. With the FLOW switch in HIGH, maximum torque available is reduced by 7 percent per engine and fuel flow increases approximately 45 pounds per hour per engine. Using the APU to power the ECS will increase fuel consumption by approximately 150 pounds per hour.

Question 4

the overpressure switch

Answer 4

When an overpressure condition exists, the overpressure switch causes the ECS HI PRESS advisory to appear. System shutdown does not occur automatically during an overpressure; the ACM is capable of withstanding full bleed-air pressure delivered by the engines or APU.

Question 5

The ECS will automatically shut down under the following conditions:

Answer 5

1. Engine contingency power is selected by either collective CONTGCY PWR switch.
2. No. 1 or No. 2 starter is engaged.
3. An ECS heating duct overtemperature exists.

Question 6

When the AIR SOURCE ECS/START switch is placed to ENG, the ECS will also shut down when:

Answer 6

1. A TGT of 851 °C is reached.
2. Either ENG ANTI-ICE switch is placed ON.
3. The DE-ICE MASTER switch is placed to ON and ice is detected.
4. An ECS underpressure situation exists.