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COMMERCIAL AIRCRAFT AUXILIARY POWER UNIT INSTALLATIONS
- Aerospace Standard
- AIR4204
- Issued
Downloadable datasets available
Annotation ability available
Sector:
Issuing Committee:
Language:
English
Scope
This Aerospace Information Report (AIR) reviews the factors to be considered in determining the location and arrangement for auxiliary power unit (APU) installations for airborne applications and reviews requirements for flight suitability.
As treated in this discussion, the APU normally includes a power section (or engine), a starting system, an electronic control unit (ECU), a gearbox with accessory mounting pads, and an oil cooling system. The accessories that are driven by the APU, such as CSD's (constant speed drives), alternating current (AC) generators, hydraulic pumps, or air compressors, are not covered here except insofar as they make demands on the APU. The various installation components and systems that are covered here are outlined by the table of contents.
Turbine-type APU's are by far the most highly developed and universally used airborne units, so their installation will dominate the discussion in this document. And, though there have been some APU's developed for military applications, many military transports are adaptations of commercial carrier aircraft. The bulk of the discussion will, therefore, be oriented toward APU installation requirements as developed by the civilian sector. Discussions of the internal design aspects of the APU itself are not within the scope of this document.
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Topic
Data Sets - Support Documents
| Title | Description | Download |
|---|---|---|
| Unnamed Dataset 1 | ||
| TABLE 1 | Example Electrical Load Analysis (KVA) | |
| TABLE 2 | Example Pneumatic Ground Requirements | |
| TABLE 3 | Minimum Fuel Inlet Pressure | |
| TABLE 4 | Typical APU/ECU Logic Functions | |
| TABLE 5 | Typical Range of Exhaust Muffler Envelopes |
Issuing Committee
AE-6 Starting Systems and Auxiliary Power Committee
Welcome to the SAE AE-6, Starting Systems and Auxiliary Power Committee public forum area.
Scope: Devotes itself to aircraft engine starting by electrical, hydraulic, or pneumatic means using stored energy sources such as batteries, hydraulic accumulators, solid or liquid propellants, stored gas, or small gas turbine engines. Develops standards for aircraft starting systems. Charter: Establish standards for aerospace and industrial engine starting, auxiliary power, and related secondary systems. For details about SAE's online privacy policy; copyright, content license, and reliability statements; and membership information, click on the link to "Info on Privacy, Copyright, and Membership" line in the folders area below. No copyrighted material may be posted in this forum. SAE is not liable for opinions expressed or information posted to this forum. All information posted becomes the property of SAE.Reference
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