Why do airplanes start at 0% RPM lever position at start?

[FTC_Frederf]

I don't know any reason why the RPM lever in all (applicable) GB planes starts at the 0% maximum coarse setting position. Why would this be done in real life? What benefit does parking the airplane and/or handing the airplane over to the pilot for start up in the maximum coarse/minimum RPM condition have?

[Gambit21]

2 hours ago, FTC_Frederf said:

I don't know any reason why the RPM lever in all (applicable) GB planes starts at the 0% maximum coarse setting position. Why would this be done in real life? What benefit does parking the airplane and/or handing the airplane over to the pilot for start up in the maximum coarse/minimum RPM condition have?

In real life are you flying the aircraft non-locally through a computer interface using separate controls?

[FTC_Frederf]

Why is the airplane starting at minimum RPM lever position?

[Gambit21]

Think about it a bit harder.

This isn’t real life.

 

How does the computer crew chief know what position your HOTAS is in?

 

 

Edited May 8, 2023 by Gambit21

[PB0_Roll]

17 hours ago, Gambit21 said:

How does the computer crew chief know what position your HOTAS is in?

Why doesn't chief position rpm lever to 100% until he knows ?

 

I don't use an axis for RPM, so crew chief doesn't need to know anything.

 

Yet he still sets RPM at 0%. Because reasons.

 

Oh, and he doesn't do it on every aircraft too, because some crew chiefs are smarter than others, probably.

Edited May 9, 2023 by PB0_Roll

[Majakowski]

It is because the previous pilot urgently needed to go to the toilet so for the propeller to stop faster after shutting down the engine, he put the pitch to full coarse to increase the resistance of the propeller blades.

[Gambit21]

4 hours ago, PB0_Roll said:

Why doesn't chief position rpm lever to 100% until he knows ?

 

I don't use an axis for RPM, so crew chief doesn't need to know anything.

 

Yet he still sets RPM at 0%. Because reasons.

 

Oh, and he doesn't do it on every aircraft too, because some crew chiefs are smarter than others, probably.

 

…and what would be the results of booting up an airplane at 100% rpm vs 0?

Compare and contrast 

 

 

[Yogiflight]

6 minutes ago, Gambit21 said:

…and what would be the results of booting up an airplane at 100% rpm vs 0?

Because you need it for takeoff?

Pretty silly question, which doesn't fit you, honestly.

[Gambit21]

2 minutes ago, Yogiflight said:

Because you need it for takeoff?

Pretty silly question, which doesn't fit you, honestly.

A state I obtain by moving the control as required. This isn’t that hard.

 

 

[Yogiflight]

3 minutes ago, Gambit21 said:

A state I obtain by moving the control as required. This isn’t that hard.

But not neccessary.

The same counts for oil cooler flaps always being closed on all aircrafts I remember, with oil temperatures at overheating temperature, while the water radiator flaps are fully open with low water temperatures. There were decisions done, which simply are hard to understand.

[Gambit21]

4 minutes ago, Yogiflight said:

But not neccessary.

The same counts for oil cooler flaps always being closed on all aircrafts I remember, with oil temperatures at overheating temperature, while the water radiator flaps are fully open with low water temperatures. There were decisions done, which simply are hard to understand.

I understand that - especially with regard to say radiator flaps etc. In any case though still something checked/set as part of pre-takeoff.

 

Anything likely (or more likely) to be bound to an axis however is a short arm movement - done. The issue here is not something that ever would have occurred to me honestly. I guess I’m just puzzled by the perceived problem.

 

 

 

 

 

[dburne]

I could understand if starting from parked cold and dark, then one should need to check and manipulate all those settings. If starting from runway with engine running the plane should already have been checked and adjusted for take off. Just imho.

[PB0_Roll]

Now I get Gambit's point, it doesn't break the game, just the immersion somewhat. This game has much bigger problems. Still, my answer to OP would be "we don't know", not "why do you care ?"

[Gambit21]

1 hour ago, dburne said:

I could understand if starting from parked cold and dark, then one should need to check and manipulate all those settings. If starting from runway with engine running the plane should already have been checked and adjusted for take off. Just imho.

 

That makes sense.

 

 

 

[RyanR]

You still gotta do a pre-flight checklist, IMHO. If you don't check what's done for take off, you'll forget what needs "undone" for climbing out. It's so easy to get complacent in IL-2.

 

-Ryan

[Yogiflight]

3 hours ago, RyanR said:

You still gotta do a pre-flight checklist, IMHO.

The thing is just, you don't have the time for that. About 5 seconds after mission start your flight starts the takeoff run. Take the Bf 110, you have to adjust your elevator trim, if you fly with bombs, set the flaps to takeoff position, open the oil radiator flaps (the oil temperature is at the border to overheating), open the water radiator flaps and turn on the navigation (and maybe the landing) lights. A lot to do for that short time. And as @dburne mentioned, when you are standing at the start, this should already be done.

[DEDMANcjp]

After mission begins and you are still paused, It would be nice to be able adjust the controls as necessary .

Pause function doesnt allow this unfortunately.

[Livai]

Do you start your car using the 100% RPM lever position, try it then you know for sure why not to do it ?

[FuriousMeow]

Just about all of this is bound to an axis or rotary for me. Exception being water rads for the SpitV and 110, and whatever planes use that. So I set my rotary/various axes to about where I want them for takeoff and do a little wiggle on them so the game acknowledges the input and controls get set in-game right after unpausing. Then I throttle up on the runway or I'm all set if starting in-air. Setting these things preemptively in the game would not help me.

[Yogiflight]

6 hours ago, Livai said:

Do you start your car using the 100% RPM lever position, try it then you know for sure why not to do it ?

Pretty stupid comment. We are not talking about the power, but about prop pitch. Starting with 0% prop pitch would be as if you try to start with your car in the highest gear.

100% prop pitch is the first gear in your car, so exactly what you want for fast accelerating from the stand.

[ZachariasX]

With some planes, IRL, you‘d probably have significant issues if the prop was set to flly coarse in „cold and dark“, as with no rpm you have no oil pressure. Hence, you had to crank the engine with the prop fully coarse to start it and it is doubtful the starter would manage. Shutting down the engine with prop fully coarse could put you on a longer stop…

 

But in the game, not having the rpm bound on an axis would be… well, special. And you need to wiggle the axis anyway for the game to catch the position. It‘s just a weird choice for the game setup.

[Skycat1969]

I looked over Chuck's Guide for Battle of Stalingrad and I see that all of the Soviet aircraft are started at minimum RPM, while in the Luftwaffe fighters the prop pitch mode is set to "AUTO" -- suggesting a difference in technical complexity from the outset. (The Ju-87 is set to minimum RPM before starting; the He-111 is set to maximum RPM.)

 

Looking for a deeper answer I came across this: https://aviation.stackexchange.com/questions/53126/did-ww2-era-aircraft-have-constant-speed-or-variable-pitch-props

 

Quote

Most aircraft made since early WW II either had a fixed pitch, or constant speed propeller. “Constant speed” means the pilot controls engine RPM through either a hydraulically, or electrically, operated control system. It really is a type of RPM governor.

Quote

This is not true. The difference between variable pitch and constant speed is the variable pitch DOES NOT HAVE A GOVERNOR.

 

So my theory is that the less automated controls in the Soviet aircraft and the Ju-87 make it necessary to start their engines at minimum RPM.

 

Delving further, I looked at 'the competition's' manual for the Spitfire IX. In that aircraft the propeller control is set to full RPM before starting. Further information describes the complexity of a constant speed propeller:

Quote

On the output shaft of the motor gear unit is the ROTOL R12/4F5/4 four-blade variable-pitch propeller. ... The propeller is automatic, capable of maintaining in-flight a consistent RPM, as set by the pilot. The blades be automatically set within a range of 35° (from 22° 20’ to 57° 20’) at any level of engine power, depending on the operation mode of the motor. This allows the pilot to take full power of the motor under all conditions of flight, as well as to establish the most economical mode of operation of the motor. Automatic maintenance of the constant RPM is performed by a constant speed regulator installed on the left side of the propeller gearbox. Depending on the speed of the motor, the regulator switches the flow of oil from the high pressure pipeline to the rod end or the rodless cavity of the propeller head. On high pitch, the rotation of the propeller blades is caused by the force of oil pressure on the cylinder piston; on low pitch, propeller rotation is caused by the centrifugal moment of the blades themselves.

 

I also checked the historic USAAF Pilot Information File from May 1, 1943 for information about propellers. The section "Ground Operation of Engines: Starting of Aircraft Engines" includes this item:

Quote

 

Make sure that the propeller controls of two position and Hamilton Standard propellers are set in the "LOW" rpm position, where they should be upon stopping the engine. About one minute after starting shift into "HIGH" rpm as this reduces the load on the engine and improves cooling.

Other constant speed propellers should be in the "HIGH" rpm position when stopped, so they will be properly set for starting and warm-up.

 

 

 

Edited May 12, 2023 by Skycat1969
Formatted the quotes

[FTC_Frederf]

On 5/8/2023 at 6:16 PM, Gambit21 said:

Think about it a bit harder.

This isn’t real life.

 

How does the computer crew chief know what position your HOTAS is in?

 

 

This has no bearing to the question. With just keyboard plugged in the RPM lever starts at full coarse. Why? Why would the airplane be parked in such a strange configuration? What purpose does this serve? What is the benefit?

 

From previous airplane operation the landing or maintenance phase will be in RPM maximum position (or nearly) naturally. Will someone after shutdown on prior flight move the RPM lever from high RPM position to minimum RPM position? Why do they do this?

[Skycat1969]

Are you defining 'full coarse' as minimum or maximum RPM?

[Livai]

On 5/11/2023 at 10:35 PM, Yogiflight said:

Pretty stupid comment. We are not talking about the power, but about prop pitch. Starting with 0% prop pitch would be as if you try to start with your car in the highest gear.

100% prop pitch is the first gear in your car, so exactly what you want for fast accelerating from the stand.

 

Not really, I know cars and plane engine are different when we talk about RPM behavior.......

 

Back to topic

-> A 0% prop pitch produce thrust when you taxi on ground at low airspeeds but low pitch not only generates drag but can also lead to engine failure from over-revving the engine when no adjustment are made when the airspeed start to increase. The prop pitch to 0% also consume less fuel and reduce engine overheating. And to last - prop pitch to 0% when the engine is dead helps to keep the plane gliding...................

[FTC_Frederf]

33 minutes ago, Skycat1969 said:

Are you defining 'full coarse' as minimum or maximum RPM?

Coarse being minimum RPM and fine being maximum RPM. Of course in most airplanes with constant speed propeller the control is RPM and few if any have direct control of pitch. In either case there are controls which are for the propeller or really anything in the airplane which should be set in a realistic way when the airplane initializes. If some airplanes were handed to the pilot with the lever forward or rearward or other position then that is how it should be.

[Yogiflight]

22 hours ago, Livai said:

-> A 0% prop pitch produce thrust when you taxi on ground at low airspeeds but low pitch not only generates drag but can also lead to engine failure from over-revving the engine when no adjustment are made when the airspeed start to increase. The prop pitch to 0% also consume less fuel and reduce engine overheating. And to last - prop pitch to 0% when the engine is dead helps to keep the plane gliding

You are missing the point of this discussion. What we are talking about is the preset settings, when starting a mission on the ground. And there are two ways to start, first on the runway, about five seconds before your flight starts its takeoff run, which gives you pretty few time to change the preset settings. And for string your takeoff run, you definitely need 100% prop pitch. Second way to start a mission is in parking position with the engine off. For starting the engine 100% prop pitch is better, too, because 0% will cause a lot more drag for the propeller blades, when starting to turn, so the starter and the starting engine need much more power to get the engine running. You can see this when starting the engines of the Bf 110 E2. You need some throttle to get the engines running, because unlike the Bf 110 G2 and all Bf 109s, which start the engines with 100% prop pitch, the Bf 110 E2 starts the engines with 0% prop pitch (no idea why, the bug report about that issue, I made, never got any reaction).

 

And about taxiing, the manual of the FW 190s advice the pilot to taxi in manual mode with 100% prop pitch. But I am with you in so far, that I taxi the Stuka, the Hs 129 or bombers with low prop pitch.

[Art-J]

Well, I could ask why all the airplanes in this sim spawn on the ground with trims set for cruise speed and power settings. Just like the RPM lever thing, It equally doesn't make sense either, would never be like that in real life, but that's just how the sim works. A bit of an annoyance, but not a critical problem.

[I./JG52_Woutwocampe]

The worst is the P-47 in that regard. So much to do on the runway before taking off yet you have like 5 seconds. Especially if you are like the 2nd one to takeoff.

[FTC_Frederf]

On 5/15/2023 at 2:54 PM, Art-J said:

would never be like that in real life, but that's just how the sim works.

Then the software must be changed if it is to be taken as a simulator. This is a bug.

[356thFS_Melonfish]

On 5/10/2023 at 8:58 PM, Yogiflight said:

The thing is just, you don't have the time for that. About 5 seconds after mission start your flight starts the takeoff run. Take the Bf 110, you have to adjust your elevator trim, if you fly with bombs, set the flaps to takeoff position, open the oil radiator flaps (the oil temperature is at the border to overheating), open the water radiator flaps and turn on the navigation (and maybe the landing) lights. A lot to do for that short time. And as @dburne mentioned, when you are standing at the start, this should already be done.

 

My usual startup procedure is to hit the starter button, set mix to auto rich, set interconnect cooler to the middle, set oil cooler to middle, throw RPM lever forward, interconnect turbo with throttle, crack the throttle an inch, hit the cockpit lights, close the nose cowl flaps down to 20%, trim rudder to Take off, then unlock the tail wheel.
the engine turns over and i'm ready to taxi.
all within the time it takes to start the engine.

For local games with the engine already running and on the runway it's still a damned quick procedure, just intercooler, oil, cowl, RPM, connect throttle and turbo, trim for take off and off you go. doesn't matter if you lag a bit you'll be overtaking them in flight anyway.
know your bird and it'll be second nature, if anything it adds immersion.

[Yogiflight]

9 minutes ago, 86th_Melonfish said:

if anything it adds immersion.

it absolutely doesn't. This has nothing to do with how it would be IRL. This has nothing to do with immersion, just making things bad for the player.

[356thFS_Melonfish]

2 minutes ago, Yogiflight said:

it absolutely doesn't. This has nothing to do with how it would be IRL. This has nothing to do with immersion, just making things bad for the player.

Well then we'll have to differ on opinion, I rather enjoy the requirement of setting up the plane before a run, I think just jumping into a pre-loaded plane and hitting go is a bit too war thunder personally.

[SYN_Mugue]

I think the reason it starts at 0% Pitch (and why the trim is set to cruise) is related to air starts. If you spawned at 100% with the engine timers as they are, you could blow the motor almost at once.(depending on the plane) And for anyone new to the game it would be very frustrating trying to figure out why things aren't working, and they might not give the game a second chance. So....this is what we have.

Edited May 19, 2023 by SYN_Mugue

[FTC_Frederf]

The RPM is set completely independent for air starts. The game clearly has the ability to set the aircraft state differently (cowl flaps, landing gear, gunsight width, supercharger, etc.) in various start conditions as can be seen by a simple check. The game has the ability to set the ground initialized lever position to any value within its range and the developers have made the choice to make that value zero.

 

[Yogiflight]

5 hours ago, 86th_Melonfish said:

I think just jumping into a pre-loaded plane and hitting go is a bit too war thunder personally.

It has nothing to do with an arcade game like Warthunder. When you start a mission in parking position with the engine(s) not yet running, the aircrafts setup should be the way it would be IRL. This means RPM/prop pitch at 100%, as you would turn your engines down with that setting, aircrafts with auto prop pitch turn them down at 100%, which makes it hard to understand why the engines of the Bf 110 E2 have the prop pitch at 0% when the mission starts in parking position. Oil and water radiator flaps should be open, as IRL the engines would overheat very fast without the cooling of the airstream so you open them when taxiing to your parking position after landing, flaps should be retracted and I set the trim to takeoff position while taxiing on the runway after landing, so it is the way I will need it for the next takeoff.

When starting your mission on the runway, the aircraft setup should be the way you enter the runway when you start your misssion in parking position. everything else is simply unrealistic and exactly contra immersive.

[356thFS_Melonfish]

Just like warthunder.

Look I get your point but that's what it boils down to, when you spawn on the runway it should be ready for you to firewall the throttle and go.
I get that argument, I don't agree with it, but then that opens a much wider discussion around general implementation and balance and further dev work to make that happen for each plane.
right now, it isn't particularly broken.

[FTC_Frederf]

18 hours ago, 86th_Melonfish said:

right now, it isn't particularly broken.

Right now it's objectively not correct for most (all?) of the airplanes. Are you aware of any model of airplane simulated that would be parked with he RPM lever or similar control at minimum position?

[Yogiflight]

18 hours ago, 86th_Melonfish said:

Look I get your point but that's what it boils down to, when you spawn on the runway it should be ready for you to firewall the throttle and go.

For me the best implementation would be starting the missions in parking position, so you have to start your engine(s) first and then taxi to the runway. But starting the mission on the runway and having to do all the setup in much to few time is absolutely off. And argumenting, having it the way it should be, when you enter the runway is arcade (this is what you want to say by the comparison with Warthunder), but doing all the stuff you shouldn't have to do anymore and then start somewhen after your squadmates, as you will catch them later anyway, is being the lonesome cowboy, who does the job nobody else can do, so purely first person shooter at its best.

[FTC_Frederf]

Starting from parking: RPM lever should be in the parking position (usually 100%).

Starting from runway: RPM lever should be in the takeoff position (usually 100%).