ECS..docx

What does the AMS use bleed air for? - correct answer • ECS (heating & cooling) • Engine start • Pressurization • Engine and wing anti-ice • Water pressure • Hot air leak detection How many AMS controllers are installed? - correct answer One controller with 2 channels which control the respective onside system What happens if a channel fails? - correct answer The remaining channel is able to control the entire AMS What provides air for the AMS? - correct answer • Engine bleeds • APU bleed • External Pneumatic Source What is bleed air used for? - correct answer • ECS (heating & cooling) • Engine start • Engine and wing anti-icing • Water pressurization What is external pneumatic air used for? - correct answer • ECS on the ground • Engine start on the ground Where is the external ground source panel located? - correct answer Lower fairing between the wings What is the primary use for APU bleed air? - correct answer • ECS on the ground • Engine starting on the ground • Assist with engine start ( FL210) • Bleed source for pressurization, heating, and cooling ( 15,000 ft MSL) Can engine bleed air flow-back to the APU? - correct answer No. A check valve prevents flow-back Where is bleed air tapped from the engines? - correct answer • 6th and 10th stage compressors (EBV and HSV respectively) • System alternates between valves to regulate an adequate and safe pressure What is normal pressure for any engine operation? - correct answer 45 psi What is the purpose of the pre-cooler? - correct answer Cools the bleed air coming from the engine to the AMS What cools the pre-cooler? - correct answer • Ground N1 fan • Flight N1 fan or ram air What does the Overheat Detection System (ODS) observe? - correct answer • Engine bleeds and packs • APU bleed • Plumbing for the wing and engine anti-icing system Do both loops have to function in order to detect on overheat condition? - correct answer Yes, but if one fails the other will work alone to detect the overheat How many ECS packs are on the airplane? What provides air for the packs? - correct answer • 2 independent packs (left and right) • Each engine provides bleed air to its respective pack Can a single pack provide adequate temperature control and pressurization? - correct answer Yes, up to FL310 Can a single bleed source power both packs? - correct answer Yes, through the crossbleed valve What is the ratio of fresh air to recirculated air? - correct answer 52% fresh air to 48% recirculated air When are the recirculation fans commanded off? - correct answer • Cockpit switch • Smoke detected in the recirc bay • DUMP button is pressed • Respective pack is commanded off What keeps the 3 avionic E-BAYs cool? - correct answer • FWD & CTR E-BAY 3 fans each pull air from cabin to bay