Questions tagged [piston-engine]
Piston (reciprocating) aircraft engines are internal combustion engines, similar to the type found in most automobiles. They are typically gasoline powered.
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Is it possible to power an ultralight airplane with a single-cylinder weed-whacker engine?
Plane:
Weighs 200 pounds.
16 FT wingspan,
36in. by 5 in. airfoil
Engine: 3,000 RPM, 2 HP
Propeller: 4ft with 4 blades and weighs 4 lbs.
Is there perhaps an equation that could determine this?
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Diesel engines market share in Piston Airplanes market
I am just trying to understand the diesel engines market-share in the piston airplanes market.
Any experience or idea about that ? Just to understand if it is 1% or 10% or more.
Thanks in advance for ...
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Constant Speed Prop Power Settings [duplicate]
I'm studying the performance data for a Piper Arrow with a constant speed propeller. The rule of thumb that I've heard is not to let manifold pressure go above RPM. This performance data seems to show ...
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Which engine is more financially economical to operate, a turboprop or gasoline engine?
I've seen a discussion about this somewhere before. I'm aware that there's no real way to calculate this. So rather then comparing weight and volume for efficiency, let's compare prices. Which engine ...
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Need help identifying a radial aircraft engine
I work at the Naval Air Station Wildwood Aviation Museum in Rio Grande NJ. We just acquired what we believe to be a radial aircraft engine that was found by fisherman in the Atlantic Ocean. We'd ...
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Can coaxial rotors be mounted on a piston engine like the Lycoming O-320?
What are the drawbacks of this compared to coaxial configuration with a turboshaft engine?
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Is there a simple formula for estimating supercharger throttling losses?
I’ve noticed that in both Aerodynamics for Naval Aviators, and most old WWII engine power charts, power vs altitude seems to be composed almost entirely of linear relationships: at a given ...
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Statistically, Is engine calendar TBO honored more in the breach or the observance?
Surprisingly to me, Lycoming and Continental engines have a recommended overhaul interval (TBO) of 12 years, while Rotax engines have a 15-year TBO. This suggests that engines should undergo frequent ...
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Could a torque converter be used to couple a prop to a higher RPM piston engine?
Every RPM reduction gearbox I look at seems to have more parts in it than a Swiss watch. Great for keeping time but many parts to wear and breakdown.
What seems especially worrisome is the direct ...
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Why are aircraft piston engines are so low rpm lazy engines?
I understand that the propeller speed should not be too much otherwise it will stall at the tip and be useless so higher rpm engine would be useless when we first think about it. However, we can put a ...
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Why do beechcraft aircraft start with full mixture and throttle?
I've noticed that barons and bonanza's tend to start with full throttle and mixture. Why do they this as opposed to other aircraft that keep throttle at 1/4 inch and put full mixture forward for a few ...
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Why don't contra-rotating propeller configurations with more than two propellers exist?
I wasn't able to find a single example of more than two propellers stacked axially in a contra-rotating configuration. There is a huge number of contra-rotating propeller setups, but it is always a ...
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Do we use static pressure in thermodynamic cycles like brayton instead of total pressure?
I observed that pressure plotted in the graph above increases from 0 to 1.
0 is inlet entrance and 0' (not shown in the graph) somewhere between 0 and 1 is compressor entrance.
Now, we know that at ...
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What is the function of the pipe referred to as "Venting Pipe" in the picture and how is it different from the exhaust pipe?
What is the function of the pipe referred to as "Venting Pipe" in the picture and how is it different from the exhaust pipe? The two photos you see in the picture are the "Venting Pipe&...
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Where exactly is the engine compartment, remarked in yellow?
Where exactly is the engine compartment, remarked in yellow? We know that normally the air going to the engine passes through the air filter. But when we open the alternate air valve, where does the ...
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In high-altitude piston aircraft, what type of forced induction (boost) is used?
In high-altitude piston aircraft, what type of forced induction (boost) is used? Turbocharger or supercharger?
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Why could a Rotax 914 light aircraft lose power at 7000 feet?
I was flying an RV 4 equipped with Rotax 914 engine and variable pitch propeller.
The problem was observed during flight above 7000 feet; vertical speed became 0, RPM overshoot for 2, 3 seconds to ...
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How safe is the Certified Rotax 912 versus the Continental O-200?
I'm thinking of buying a taildragger LSA, many of which have a Rotax engine. Continental and Lycoming are the major suppliers of certified piston aircraft engines, and they are considered to be safe ...
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Carbureted Rotax engines have no mixture control, how do they handle less dense air?
Rotax engines have no mixture control, yet they don't seem to have any more problems than other engines at altitude. How do they handle the lower air density in order to not get a too rich a mixture?
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Why can we not use full throttle in a C172 when cruising at lower altitudes?
My flight training manual (FTM) says that at low altitudes we throttle back our trainers in order to not exceed recommended power settings. We us the Lycoming O-320 engine.
But why is that? Is the air ...
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Why is carb icing an issue in aircraft when it is not an issue in a land vehicle?
As far as I know, the mechanics and physics of an aircraft carburetor are the same as those of an automobile carb. (If I'm wrong, there is no basis for this question.) Aircraft carbs are provided with ...
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Why does fuel vaporize in the carburetor?
So I get that a carb vaporizes fuel and mixes it with the air intake for the engine. But my question is what is the explanation for what causes the fuel to vaporize after it exits the fuel nozzle?
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Why do piston engines in aircraft burn fuel at a higher rate than a comparable car engine?
I've never understood why piston powered plane engines burn such a large amount of fuel per time period than car engines.
Can anyone elaborate on this?
I know that a C172M will burn ~5-9+ gph at ...
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Why the lack of faster piston-powered planes?
There aren't very many fast piston airplanes in production. By "fast" I mean, if you look back in the early to mid 20th century, before turbines won out, there were lots of piston airplanes in ...
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Estimating piston-engine thrust on take-off
In my Uni course I've learnt how a piston-engine produces a constant power, as opposed to a constant thrust like in a jet engine, which can be estimated as Thrust = Power / Velocity. However, using ...
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Why Rotax 912 "burps the tank"?
The Rotax 912 engine has dry sump forced lubrication system. They say rotating the prop in the correct way (counter-clockwise when looking from the prop side) will get the oil from the bottom of the ...
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How much horsepower do I need for my paramotor?
Assuming my full kit and I weigh 82kg total, I have estimated that I need 5hp. To calculate this, I used the formula:
weight force (W) is F = m g
W= 82kg*9.8 ms/2 =401.8 Newtons
Now, if the drag ratio ...
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Why does airspeed increase with more throttle if RPM stays the same?
Given a constant speed propeller, the RPM will stay the same because of the governing system which changes the blade angle. But in cruise flight if you add more power and keep the RPM's the same, ...
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Recording tach solutions for a tachometer generator
I am most familiar with cable driven recording tachometers. I have a tach-generator on a continental IO-470, which has been driving a two-hand tachometer with no time recording feature. I would like ...
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In what way is a Rotax 914 F2/S1 different from a standard 914 F2?
Rotax manufactures the 914 F2/S1 variant, which is (at least) used in Stemme's S10 and S12 self-launching gliders.
What are the differences between the F2 and the F2/S1?
Bonus question: Why have any ...
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C-152 carb heat on before landing in hot weather?
I know the POH for the C-152 explicitly states carb heat should be applied before landing. I fly in a tropical country where temperature is at 30°C on average on the ground, twice the standard temp. ...
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Jumo 222 What are the design choices that lead to this particular nose cone and spinning cowling setup?
Looking for Jumo 222 powered aircraft, I came across this picture of a Junker Ju 288, with this strange spinning cowling and propeller setup, what are the considerations behind this design, how does ...
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Why was my Exhaust Gas Temperature considerably lower than usual?
I have been trying to understand the exact details of an EGT gauge, specifically to understand why on a recent flight it was (for a short time) reading much lower than I would have expected.
I would ...
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Why do older pistons crank for a while before starting?
Watching older planes startup I noticed they crank for a little bit before starting. Why do they also shoot out flames when starting? Mostly in Mustangs and Spitfires.
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Why do carburetors tend to produce richer mixture at higher altitude?
The pressure drop in the venturi is proportional to air density and the fuel is at ambient pressure in the float chamber, so I would expect the fuel flow to reduce proportionally with density, and ...
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Why does manifold pressure increase with power?
Whilst writing an answer to this question, I remembered something I don't really understand.
The partial vacuum in the inlet manifold is caused by the piston descending with the inlet valve open ...
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Is a Cessna 162 safe to fly if engine RPM drops by 160 on one magneto?
On a Cessna 162, during engine runup I switch to one mag, and the engine RPM dropped by 50, but on the other mag the RPM dropped by 160 while the POH says maximum allowable drop is 150. Is this plane ...
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Do constant speed propellers actually increase fuel efficiency?
I have a few questions regarding constant speed props. As a pilot who just recently moved up to aircraft equipped with constant speed props (Cessna 182, Piper Dakota), I understand that a constant ...
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Why isn't Yamaha EPeX300Ti more popular in aviation?
The answer to this question might be obvious to experienced aviators. But as an armchair enthusiast, I really couldn't find a satisfactory answer anywhere on the internet.
Below two pages came from ...
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What's the reason of engine roughness while leveling off from climb or recovering from stall?
I want to find out that if relative wind pressure can affect engine or not.
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At what speed will the crankshaft be rotating if each cylinder of a four-stroke cycle engine is to be fired 200 times a minute?
Well the answer is 400rpm ; but I don't understand how.
Here's my thought process:
4 stroke engine would mean every piston is in a different stage (intake, compression, power, exhaust)
Which means 200 ...
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Why does engine temperature rise upon applying carburetor heat?
When carb heat is applied, the mixture enriches due to hotter and less-dense air mixing with the fuel. But a richer mixture has the side effect of cooling the engine down. So why does carb heat cause ...
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Could a Continental R-670 piston engine run with regular car gasoline?
I know that the minimum octane for the R-670 is 65 octanes (W670-K variant). I also noticed that other variants increase compression ratio and power using a minimum of 80 octane. Why there is an ...
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static thrust vs. prop RPM data?
edit: question was too long, and is actually simple, so I removed unneccesary description
Background:
There are many questions here about:
propeller efficiency
changes to thrust when it is dynamic
...
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What happens if you change power setting with constant mixture setting?
For a given Cruise Setting: Manifold set / RPM set / Mixture set according to P.O.H. values: what happens to the Mixture if you were to reduce power or increase Power by varying throttle? Does a ...
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Are rotary engines the same as piston engines?
I’m researching into piston engine powered, propeller driven aircraft.
However, I’m really struggling to find manufacturers that make "piston engines".
For example, I came across Rotron, but ...
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Propulsion/ power plant
Let’s say I require 100Hp as stated by my calculations of Thrust for an aircraft-
When finding a power plant for this, would it be better to use a power plant with more Hp or exactly that 100Hp please?...
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Are these units correct for Hp/W
using the table provided, and how it says the Velocity should be in mph, is it correct to say that the units of Hp/W from this table is mph also?
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What are the differences between Lycoming and Continental engine designs?
Inspired by a discussion in chat.
Most GA piston singles are powered by either Lycoming or Continental engines.
The engine designs used by both manufacturers are broadly similar (4-cycle, ...
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Why do propeller driven planes have intakes/inlets, such as this one on the P-51 Mustang?
Specifically talking about the p51, why do they have intakes? Don't propeller-driven planes not require any sort of intake because the propeller is what propels it by pushing air behind it?
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