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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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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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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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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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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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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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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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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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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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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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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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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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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What downsides could there be to not letting your engine's oil temperature get above the given limit to taxi/take off before you do so?
I'm not a pilot, and I'm sure most pilots who fly piston aircraft would know this, but what could happen if you operate an aircraft with an oil temperature lower than what the checklist says you ...
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How does detonation and pre-ignition affect EGT/CHT readings?
I've read that during engine detonation EGT decreases and CHT increases. In contrast, when pre-ignition occurs both EGT and CHT will rapidly increase.
Unfortunately, I can't find a good explanation ...
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Am I calculating the fuel consumption correctly?
I'm trying to calculate the fuel consumption for l550e engine. In its datasheet you can see this graph:
At 6500 RPM, engine power is around 48hp and the SFC is 345g/HPh. Ok, then the fuel consumption ...
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Why does a fuel-injected engine have a mixture control?
For example, in a C172S fuel injected type, what does the mixture control lever control exactly in the fuel system?
They have a fuel air control unit which regulates fuel flow based on air passing ...
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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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Does throttle equal power on a turbocharged piston engine?
On a normal piston engine powered airplane, throttle equals power. If I set the throttle to 50 %, I will get 50 % of the power the engine can develop at the current altitude, temperature, etc. In a ...
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Does a diesel piston engine's power decrease more slowly with altitude than with an AVGAS engine?
I have a power-altitude curve of the Austro Engine AE-300 provided by manufacturer and I don't know the reason why power decrease lower than other engines. The curve is in the end of the pdf in this ...
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How does the pressure distribution at the blades of a radial turbocharger look like?
Consider a piston engine equipped with a turbocharger.
In the turbine section of the turbocharger, the pressurized exhaust airflow comes from the center (radially) to the blades, then changes ...
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Why oil pressure decreases when coarsen the pitch during run-up?
During run-up checks, we set the
Throttle such a manner that RPM IS 2000 then we do run-up checks
Magneto check
2.prop check
Notice RPM drop
MAP increases
Oil pressure decreases
Why does MAP ...
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What is vapor lock?
Vapor lock occurs in piston engines especially during summers.. before starting engine we prime it and the engine starts but as soon as we reduce it to near idle or just above idle, engine tends to ...
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Why does RPM increase when you lean the mixture in constant speed propeller engine? [duplicate]
In constant speed propeller aircraft like Diamond star DA-40, during run-up checks the AFM mentioned to increase throttle to increase RPM to 2000 and then do magneto check then rpm check then mixture ...
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How much drag is actually caused by open cowl flaps?
I am modelling the Cessna 210 for FlightGear, which has cowl flaps. I want the model to be as realistic as possible, and so, I want to know: how much drag do cowl flaps produce ? I could not find any ...
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Engine Bearings Damage in Radial Engines
Studying the P47's dive performance in DCS, I noticed how it's easy to damage the engine bearings if you windmill the prop at high speed.
Doing some research, I discovered that all radial engines are ...
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Why have propeller engines never been mounted on the tail in production transport aircraft?
Recently, Embraer teased this concept.
Unlike jet engines, I have never heard of a production airliner or executive aircraft that mounted propellers on the tail like this.
From the source:
the new ...
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What is the metal sheet in front of the engine called on a Cessna 182 or similar?
I need to know the name of that metal sheet covering the front of the engine in small Cessnas (specifically the Cessna 182), just behind the propeller. I mean the one where the cowl plugs are put into:...
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BHP increases with Altitude
Searching on internet, I found some performance charts of the Merlin Engine BHP output:
As you can see there is an increase in BHP,(mainting a constant Boost Setting), until reaching the critical ...
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Why is the RPM limit on a Lycoming IO-540 different in the -C and -D versions?
On a Lycoming IO-540, it seems there is a Max RPM difference between the -C and -D versions (and thus a max HP difference too). Does anybody know what is different in the engines that causes this, or ...
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