What does the APU do on a 737?

What does the APU do on a 737?

The APU is a source of bleed air and AC electrics for the aircraft, this gives independence during turnarounds, electrical backup in the event of engine failure and provides air conditioning & pressurisation during an engine bleeds off take-off.

Where is the APU on a 737?

For Boeing B737 and B747 aircraft, the APU is located inside a compartment in the tail section of the aircraft and is completely enclosed by a sound-reduction fire-proof titanium shroud.

What APU is on the 737 Max?

APU. The MAX APU is still a Honeywell 131-9[B] but is updated to series 41 which has various minor improvements such as improved starting reliability.

Why did Sully turn on the APU?

In its report on Flight 1549, the US National Transportation Safety Board said that Captain Sullenberger’s decision to start the APU was “critical because it improved the outcome of the ditching by ensuring that electrical power was available to the plane.”

Can the APU be started on battery power in flight?

The APU can be started utilizing only the aircraft battery(s) and, once running, will provide electrical power to aircraft systems as well as bleed air for air conditioning and for engine start.

How do I start my APU?

APUs are like small jet engines, small enough to be started electrically. So you would use the power of the battery or an electric ground power cart to spin up the APU by its electric starter motor, and then introduce fuel into it once its spinning fast enough, just like a jet engine is started.

Does the 787 have an APU?

Because the 787 uses more electricity than do other Boeing airplanes, the 787 generates more electricity, via six generators: two on each engine and two on the auxiliary power unit (APU, a small turbine engine in the tail).

Did Sully use flaps?

Sullenberger used Flaps 2. The manuals are clear. “If no power is available, a greater than normal approach speed should be used until the flare. The speed margin will allow the glide to be broken early and gradually, decreasing the possibility of stalling high or flying into the water.”

Can you fly without APU?

Aircraft are allowed in general to fly without an APU. Exceptions are flights with two-engined aircraft and long routes over water or terrain without an alternate airport – so called ETOPS flights. ETOPS stands for Extended Twin Operations.