I have a basic flight simulator (currently consisting of a laptop running FlightGear, a homemade yoke, and an Xbox controller), and I usually use the Piper Cherokee in FlightGear. Once I get to the desired altitude, I adjust the yoke until I get to cruise speed, then I adjust the power until the VSI shows 0. Is that the right way to fly a single-engine piston plane?
Am I flying my simulator correctly?
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murphey
Touchdown! Greaser!
Not just power. You also want to trim (which adjusts the ailerons and the yoke) so that the AI is between 0 and +5 deg and the VSI is 0. This produces the least drag, hence the best speed. Don't know about your sim, but my cherokee 180 really likes 2400 rpm for cruise. I dunno why, but it does. But then, I usually cruise anywhere between 9500 and 11,500 MSL.
There's more than just setting power and yoke - trim is your friend and there are physical characteristics of different wings, aka NACA as well as the angle the wing is attached, e.g. the dihedral. If I set the AI to 0 deg, I'm really pointed down a bit. My AI is set for 5 deg + for best speed (least drag). If you really want to dig into all this, Aerodynamics for Navy Aviators (1965). Yes, it's that old and still the best. Even the Navy hasn't seen any reason to improve it.
There's more than just setting power and yoke - trim is your friend and there are physical characteristics of different wings, aka NACA as well as the angle the wing is attached, e.g. the dihedral. If I set the AI to 0 deg, I'm really pointed down a bit. My AI is set for 5 deg + for best speed (least drag). If you really want to dig into all this, Aerodynamics for Navy Aviators (1965). Yes, it's that old and still the best. Even the Navy hasn't seen any reason to improve it.
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Thank you! I'll set up buttons on my controller for trim. I'll take a look at that book, thank you! I think I have a PDF on my laptop, but I haven't read it yet.
murphey
Touchdown! Greaser!
Here's the difference between sim and actual. It really depends on both the sim yoke and the actual aircraft yoke. On the cherokee (and all other aircraft) the yoke can be moved without touching it because the winds affect the ailerons, which control the roll, so it really isn't "set and forget". Remember, the yoke controls the ailerons. In calm weather, no problem. The advantage of trim is once you are set for straight & level (or approach to landing) the trim removes the "effort" to keep the ailerons (and the yoke) stable.
The yoke (or stick) is the primary flight control. Virtually all changes in attitude will originate here, and any temporary changes also end here. If you take your hand off, the plane returns to the original attitude, in the small GA aircraft we fly (look up "stability").
When you want to make a permanent change, you set the new attitude using the yoke (or stick) and then trim until the required pressure goes away. When you take your hand off the yoke (or stick), the plane remains in the new attitude.
Some aircraft, including the cherokee, also have a rudder trim, but let's not go there right now.
dmspilot
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Does your yoke not have a centering spring or does it just stay wherever you leave it?
In a real airplane, when you let go of the yoke, the elevator (and ailerons) will streamline themselves. The streamline position of the elevator, and thus the yoke position, will depend upon the trim sitting (and prop-wash).
In a consume-grade simulator yoke, this would be simulated with a centering spring. Without a force-feedback feature it won't be able to simulate the yoke moving as the elevator moves with the trim setting, however, it can still simulate in-trim or out-of-trim as centered or not centered.
Oh, I was not aware of that. I thought the yoke stayed where you put it. I'll figure out some way to make it re-center itself. Thank you!
Pinecone
En-Route
When you level off in a real airplane, you push the nose over to about level, leave the power up to accelerate. Then when you get close to your cruise speed, you set the power desired, then adjust attitude to not climb or descend and trim off the pressure so when you take your hand off the yoke, the nose does not go up or down.
These are sort of done in a flow, not like individual steps.
These are sort of done in a flow, not like individual steps.
Thank you! I got elevator trim working as expected. I also tried to set up aileron trim, but it doesn't seem to make any difference in flight, and I can't find any control in the cockpit that moves. I did try rudder trim, and that works as expected and moves this knob.
ArrowFlyer86
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The Little Arrow That Could
Aileron trim isn't a standard feature on Cherokees. If you can't find a control for it in the sim, my guess is the plane doesn't have it. You shouldn't need it flying a Cherokee.
In my piper cherokee arrow I had aileron trim and it was controllable via a dial next to TC (see below). I had the tab/servo removed but haven't had the actual control switch for it removed yet which is why it shows a full left deflection (reminds me, I have to put an INOP sticker on that!).
Thank you! Should I set the left-right joystick axis to rudder trim?
ArrowFlyer86
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Definitely not...
Silvaire
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You are letting the trim position determine your power setting and speed. You can get the plane to fly level at any trim position by adjusting power but if you want to fly at a specific power setting (that is, normal cruise) then you'll need to adjust the trim to maintain level flight at that setting.
Thank you! So once I get to the desired altitude, I should set it to a certain power setting, then adjust elevator trim so it flies level with the yoke centered? What power level should I set it to?
jesse
Touchdown! Greaser!
In a normally aspirated (meaning there is no turbo/supercharger) piston airplane, with a fixed pitch prop, in most cases, you'd:
Takeoff:
1.) Throttle smoothly to full power
Climb:
1.) Throttle is still set to full power
2.) Set your pitch to maintain whatever climb airspeed you want, typically Vy (or higher if needed for cooling).
3.) Trim to eliminate any yoke pressure, the airplane should continue to maintain your desired climb speed with your hands off the yoke
Cruise:
1.) Throttle is still set to full power (where it remains)
2.) Push forward on the yoke, while adding some nose down trim, trying to get to where the airplane maintains altitude with your hands off the yoke. Note: A good pilot can quickly stop the climb, but the airplane will continue to accelerate, and as that occurs, the pilot will continue to add nose down trim. Eventually everything balances out, but it can take a minute or two.
In most fixed-pitch normally aspirated airplanes, by the time you get to your cruise altitude, the airplane will not be capable of exceeding red-line RPM (or anywhere near it really) at full power (the air is thinner). Because of this, you do not typically do anything less than 100% throttle until at some point in the later stages of the descent. There are things to do with the mixture in these various phases, but, I am lazy and didn't bother to write it.
Also note that you do not attempt to achieve any speed in cruise - you get the speed you get. In the real world, that speed is never as fast as you'd like, so you sit there thinking about how if only you made 50% more money you might be able to afford to go 10% faster! Drag is an unfriendly bastard who doesn't maintain any sort of linear relationship with money.
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I thought you were supposed to use the throttle to change altitude?
jesse
Touchdown! Greaser!
For the climb, there is no reason to change it, because you set it at takeoff. For the descent, there is no reason to initially change it, as you might as well take the extra speed in the descent. Typically it is reduced at some phase in the descent, but not until sometime near landing.
Things would be different if you're talking about a jet. Or even some more performance oriented piston aircraft.
Pinecone
En-Route
If you level off and reduce power, if you want to climb, you may or may not go back to climb/full power. If I am only going to climb 1000 feet or so, I will typically just raise the nose and let the speed reduce a bit. If more than 2000 feet, I will set climb power.
If you want to know what cruise power setting, you need to get the POH for that airplane. It doesn't have to be the exact model (a 172 POH is pretty much a 172 POH), but typical cruise power settings are 75% for speed, or 65% for longer range and longer engine life (not an issue on a sim). For a normally aspirated engine (no turbo), around 8000 feet, full throttle will be about 75% or less.
Also, the higher you fly for the same power setting, the faster the airplane is actually moving. The Indicated Airspeed stays the same, but due to lower air density, the airplane is moving faster and the True Air Speed is higher.
If you want to know what cruise power setting, you need to get the POH for that airplane. It doesn't have to be the exact model (a 172 POH is pretty much a 172 POH), but typical cruise power settings are 75% for speed, or 65% for longer range and longer engine life (not an issue on a sim). For a normally aspirated engine (no turbo), around 8000 feet, full throttle will be about 75% or less.
Also, the higher you fly for the same power setting, the faster the airplane is actually moving. The Indicated Airspeed stays the same, but due to lower air density, the airplane is moving faster and the True Air Speed is higher.