auxiliary power unit

[ȯg′zil·yə·rē ′pau̇·ər ‚yü·nət]

(aerospace engineering)

A power unit carried on an aircraft or spacecraft which can be used in addition to the main sources of power. Abbreviated APU.

auxiliary power unit (APU)

A power generation unit for operation of systems like hydraulic, air conditioning, electrical, and avionics. It may provide AC (alternate current) or DC (direct current) supply. The APU is normally used prior to starting the aircraft and for testing systems on the ground. In rare cases, it can provide some thrust in an emergency. Ground auxiliary power units provide current for starting engines. See airborne/auxiliary power unit.

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References in periodicals archive

For product type segment, this report listed main product type of Aerospace and Military Auxiliary Power Unit (APU) market

Aerospace and Military Auxiliary Power Unit (APU) Market 2019: Global Key Players, Trends, Share, Industry Size, Segmentation, Opportunities, Forecast To 2024

'With the procurement of these machines PIA will save millions of rupees per year by keeping the APU (Auxiliary Power Unit) off on the ground, in addition to giving passengers a cool cabin during summer season, giving them a better flight experience,' he added.

PIA gets AC vehicles to keep aircraft cool

The Japan Transport Safety Board said Wednesday it will conduct an analysis of a battery for the auxiliary power unit used in Boeing Co.'s 787 Dreamliner operated by All Nippon Airways Co.

Japan to look into auxiliary battery of ANA's Dreamliner

Honeywell announced that it will provide a suite of its safety and navigational avionics to operate aircraft more efficiently and safely, as well as its fuel-efficient Auxiliary Power Unit (APU), to AWAS, one of the world's leading aircraft leasing companies.

Company Watch - Honeywell

For example, the APU cover provides just a little protection for the auxiliary power unit (APU).

Watch where you tread!

The two Navy teams are the Navy/General Electric (GE) F404 PBL Team (sub-system level winner), and the Navy/Honeywell Auxiliary Power Unit Total Logistics Support (APU/TLS) PBL Team (component level winner).

Naval Supply Systems Command Office of Corporate Communications (Nov. 23, 2005): two NAVICP teams recognized with DoD performance based logistics awards

The company said it has implemented several new procedures to minimize fuel use, including reducing the amount of extra fuel carried by aircraft, using only one engine during taxiing and having more airplanes use electrical power from buildings and in-ground electrical hook-ups, instead of the aircraft's auxiliary power unit. Additionally, UPS said it is slowing down flights to the "most fuel-efficient speed possible if it doesn't change an arrival time critical to making service commitments."

UPS Airlines Implements New Fuel-Saving Measures

Each was propelled by three installed jet engines, plus an auxiliary power unit (APU).

Deduct or capitalize aircraft engine maintenance costs?

"But the 'silent watch' capability of this vehicle increases battlefield effectiveness, and reduces the need for generators and all of the on- and offsite staff necessary to support this equipment." An on-board hydrogen fuel cell auxiliary power unit complements the military Silverado's 30-kW diesel generator, which itself eliminates the need for a portable generator unit.

Hybrid COMBATT. (WIP)

The UK's Air Accidents Investigation Branch (IB) said that this heat damage is remote from the area in which the aircraft main and Auxiliary Power Unit (APU) batteries are located.

Boeing 787 Heathrow fire incident not co-related to battery problem, investigation reveals

The company said it provides the A400M's Secondary Electrical Power Distribution Centre (SEPDC), Auxiliary Power Unit (APU) and Ram Ai Turbine (RAT) emergency power system.

Flight tests of the A400M show Hamilton Sundstrand systems performing well