Low Speed Pre-Ignition (LSPI), also referred to as Stochastic Pre-Ignition (SPI), Superknock or Megaknock is an undesirable combustion phenomenon that limits the fuel economy, drivability, emissions and durability performance of modern turbocharged gasoline engines. Numerous studies have previously reported that the frequency of LSPI is sensitive to engine oil composition. One of these drivers is the concentration of Calcium, which is usually delivered in the form of a detergent in the additive package. Switching to completely all-Magnesium detergent and/or severely limiting the concentration of Ca in the engine oil have recently been proposed as potential means to reduce LSPI. In this work, we evaluate the impact of detergent type on LSPI performance as well as on other performance that the modern engine oil needs to deliver. Particularly the impact of detergent type on Fuel Economy performance is evaluated. To ensure a rigorous and high precision measurement of the impact of engine oil on fuel economy, representative of real-world conditions, under well-controlled conditions, the ASTM D8114 test (Sequence VIE) was used to quantify fuel economy performance…

This specification covers an aluminum alloy in the form of alclad sheet 0.040 to 0.187 inch (1.02 to 4.75 mm) inclusive in nominal thickness (see 8.6).

This document provides informational background, rationale and a technical case to allow consideration of the removal of the magnesium alloy restriction in aircraft seat construction as contained in AS8049B. The foundation of this argument is flammability characterization work performed by the FAA at the William J. Hughes Technical Center (FAATC), Fire Safety Branch in Atlantic City, New Jersey, USA. The rationale and detailed testing results are presented along with flammability reports that have concluded that the use of specific types of magnesium alloys in aircraft seat construction does not increase the hazard level potential in the passenger cabin in a post-crash fire scenario. Further, the FAA has developed a lab scale test method, reference DOT/FAA/TC-13/52, to be used as a certification test, or method of compliance (MOC) to allow acceptability of the use of magnesium in the governing TSO-C127 and TSO-C39C. Other flammability studies are also cited in the AIR document to substantiate the FAA findings.

This specification covers an aluminum alloy in the form of plate 0.250 to 5.500 inch (6.35 to 139.70 mm), inclusive in nominal thickness (see 8.5).

Many modern engine platforms use turbochargers to meet higher fuel economy performance, which is often combined with downsizing the engine displacement. Operating downsized, turbocharged, direct injection engines at low speeds and high loads has led to an abnormal combustion phenomenon known as Low Speed Pre-Ignition (LSPI), wherein the fuel-air mixture ignites before the spark occurs. LSPI can lead to extremely high pressures in the combustion chamber, which can damage hardware such as pistons, piston rings, and spark plugs.Lubricants, fuels, and engine operating conditions have been shown to impact LSPI. Any of these can be modified to improve LSPI performance. One solution which has been used widely in the industry is reformulating the lubricant additive package. In particular, calcium-based detergents have been shown to promote LSPI, while magnesium detergents appear neutral to LSPI. Reducing the usage of calcium detergents can impact other performance areas such as deposit control and fuel economy, and limits formulating flexibility. Finding an additive solution to LSPI which does not require a reduction in calcium allows for more component options in formulating…

This specification covers an aluminum alloy in the form of plate 1.000 to 6.000 inch (25.40 to 152.40 mm), inclusive, in nominal thickness (see 8.4).

This specification covers an aluminum alloy in the form of sheet 0.009 to 0.126 inch (0.23 to 3.20 mm) inclusive, in nominal thickness, alclad.

This specification covers an aluminum alloy in the form of die and hand forgings 4 inches (102 mm) and under in thickness, rolled or forged rings 2.50 inches (63.5 mm) and under in radial thickness, and stock of any size for forging or rings (see 8.5).

This specification covers a magnesium alloy in the form of die forgings 3 inches (76 mm) and under in nominal thickness at time of heat treatment, hand forgings 6 inches (152 mm) and under in nominal thickness, and forging stock of any size (see 8.5).

This specification covers aluminum and aluminum alloy foil in the form of laminated sheet.