17k views

### Why is the Tu-95 so efficient despite having propellers that spin faster than the speed of sound?

I've ready many, many times that propellers are not efficient near the speed of sound because it's so hard to get a tip-speed above Mach 1. Then I came across this: It's the Tu-95 "Bear", a ...
79k views

### Which engine is more efficient between turboprop vs jet?

Are turboprops really more efficient than jets? If yes, does that mean that airlines who use jets sacrifice fuel for faster flights?
12k views

### Why are propeller engines uncommon on airliners?

My experience in aviation is essentially zero, but looking at Wikipedia it seems like the Tu-95 Bear offers high subsonic speed and extreme range. I assume that turboprop engines are more fuel ...
8k views

### Why did the turbojet replace the piston engine?

Many people say that this was because aircraft powered by turbojet engines were faster during WWII. However the Grumman F7F-4N Tigercat, a fighter powered by a piston engine, flew at a maximum speed ...
6k views

### In what way are the Concorde's engines considered efficient?

The Concorde is powered by a bunch of Rolls-Royce/Snecma Olympus 593 turbojet engines. Much has been said about how efficient they are at speed, and the fact that they allow long-range cruise at Mach ...
22k views

### Can propeller driven aircraft sustain speeds at or above Mach 1?

Has any propeller driven aircraft ever achieved and sustained supersonic speed? If not, why can't propeller airplanes achieve that speed?
70k views

### What is the fastest single-engine civil turboprop aircraft with cabin seating?

I was having a discussion with some friends about general aviation aircraft with cabin-class seating. We were discussing cruise speeds and there were some "shop talk opinions" flying around about what ...
13k views

### Are turboprops more efficient than piston engines (thrust per fuel consumption)?

I want to compare two types of engines: Turboprops and piston engines. I want to know which one is more efficient. There are many types of efficiencies, so I will specify: thrust (in newtons) per fuel ...
4k views

### Why is max endurance different for jet and props?

Max endurance speed is not the same for gliders, propeller planes (also for turbo prop, right?) and jet planes. While for for jet planes max endurance is at the minimum drag speed ($V_{md}$), for ...
2k views

### What does the 'hp' rating actually signify, with respect to an aircraft engine?

Let's say I've got a Cessna C172S with a Lycoming IO-360-L2A engine that produces 180 hp (that's the power output for sure). Let's say I've also got a water pump, that is rated at 1 hp (power input or ...