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## What is the rpm of a jet engine?

An airplane׳s engines often run faster than its propellers. For example, on one airplane, the most efficient engine speed is **3,000 RPM**, while the most efficient propeller speed is about 1,500 RPM. A set of reduction gears permits the engine to run at 3,000 RPM while the propeller turns at 1,500 RPM.

## How much force does a jet engine produce?

“Todays jet engines commonly develop **9,900 pounds of thrust or more**.” “Jet Engine.” Encyclopedia Americana. New York: Anderson, 1996: 51. “It was strictly an experimental aircraft, but von Ohains engine of 838 pounds of thrust pushed the HE 178 to a maximum speed of 435 miles per hour (700 km/hr).”

## How do you calculate volume flow through mass flow rate?

**Divide the mass flow by the density**. The result is the volumetric flow, expressed as cubic feet of material. An example is: 100 pounds (mass flow) / 10 pounds per cubic foot (density) = 10 cubic feet (volumetric flow).

## How do you calculate mass fuel flow rate?

Mass flow rate can be calculated by **multiplying the volume flow rate by the mass density of the fluid, ρ**. The volume flow rate is calculated by multiplying the flow velocity of the mass elements, v, by the cross-sectional vector area, A.

## What is the difference between mass and mass flow rate?

Volume flow rate is the amount of volume flowing through a cross-section. Mass flow rate is the **amount of mass passing** through a given cross-section.

## How many horsepower is a 747 engine?

The power per engine for the two aircraft is seen to be 14 984 horsepower and **1646 horsepower** for the 747 and Super Constellation, respectively.

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Characteristic | Lockheed 1049G | Boeing 747 |
---|---|---|

Number of engines | 4 | 4 |

Total cruise power, hp | 6 585 | 59 934 |

Power per engine, hp | 1 646 |
14 984 |

Dry engine weight, lb | 3 675 | 8 600 |

## What rpm is 777 engine?

The GE90—installed on some Boeing 777s—is typical in that the fan stage (N1) rotates at a **maximum of 2,550 RPM** while the compressor stage (N2) rotates at a maximum of 10,850 RPM. The blade tips, at 11,000 RPM, are well above Mach 1, which partially accounts for the high noise levels of a jet engine.