I think I am using Pitch trim incorrectly

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Styggron
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Re: I think I am using Pitch trim incorrectly

Post by Styggron »

Oracle427 wrote:I'm just answering your question, I understand that you aren't flying using standard procedures.

Very generally speaking if you are talking to ATC and they tell you to climb or descend to an altitude, they expect a minimum of a 500FPM rate. If you can't maintain that rate which is possible due to a hot day in a heavy plane at high power setting, you need to advise them that you are unable.

2. If there is a mountain ahead I take the controls
So how do you plan to ensure that you climb at the fastest rate or angle to clear the mountain. I was actually wrong when I typed Vx on my bus ride home. I meant Vy. Vy is the airspeed that provide the best RATE of climb at a given altitude and loading. At this speed you'll get your best sustained vertical climb speed.

3. Climb vx ? no idea what vx is sorry
Vx is the best angle of climb. It allows you to cover the least lateral distance while climbing, but it trades climb rate to minimize distance.

4. target altitude ? depends what I want at the time I guess. I set alt capture and it's done
There are VFR altitudes to fly depending on your heading to help with separation from other aircraft. Could be risky to be at the wrong altitude going the wrong way in a busy airspace.

6. Ground speed ? no idea I don't look at that I check airspeed only
Ground speed is very important in flight planning. One needs to keep track of their progress over the ground to determine how much time they'll need to get to their distination. Fuel consumption is based on time at a given power setting. This is also important when determining where you will be or need to be when changing altitudes, turning, planning to avoid obstacles, etc.

7. 3/6 rule ? sorry not heard of that
3/6 rule helps in descent planning. 3xaltitude in thousands of feet to descend = distance to begin descending and 6xgroundspeed = rate of descent. Using this rule you should generally be able to arrive fairly close to a point over the ground at the desired altitude from a higher altitude.

8. What is the distance I need to be before that altitude ? This is something I choose completely when just flying around.
For VFR flying around without a plan outside of busy airspace, this is perfectly okay. When you get near busy areas or arrive at a busy airport, you need to be at the right altitude at the right place to ensure orderly entry into the traffic pattern.

There is a lot of constant evaluation decision making going on and a lot of structure to make the behavior measurable, predicatable and therefore safer. If everyone just goes and does anything it can get very confusing and dangerous. Anyway, in the sim world none of this applies, but just background.

The trim is a tool and like any tool it can be used incorrectly to the detriment of the user.
You're not going to like some of these answers

1. Your first point re ATC. Yes they can advise you but there would not be an FSX option that says "sorry I can't do that" unless I am mistaken ?
2. if the mountain is there and I can't climb then I press Y and I "slew" :D However saying that, it is my preference NOT to because circumventing all the realism is profligate.
3. Ok best angle of climb but where is this said, on a chart ? the plane specs etc ?
4. Errrrrr unless ATC is telling me I have no idea, I just pick a height and go for it. If I fly the Aerosoft Airbus that's another story as I put it all in the FMC and it does it all
5. there is no 5
6. Ok. Time I just use DME if available but I never know WHEN I need to change altitudes. This is my problem actually. I am always too high so with practie I just know where the glideslope is so aim for that. I think this info is in an airport chart ?
7. Gotcha. Goodness this one is very important..
8. All I do is contact ATC and they give me clearance and I land. That's all I know I fear. They don't vector me in because I don't file a flight plan. What I should do is start using a flight plan and get ATC to vector me in......yes ? Hopefully they will say climb to this and head this this degrees decend to this and this yes ? At least I hope they will.

I think trying to circumvent the realism though is profligate. As I learn more and more albeit VERY slowly as I find this tricky, I do get better. What you have here is FANTASTIC because it covers REAL WORLD which is what a simulator is trying to simulate.

Therefore, I need to read CAREFULLY everything you wrote here and learn to do it RIGHT. If I wnat to faf around, I always can.

So what I need to do is
* File a flight plan. I tend to just jump in and fly.
* check the airport chart. Well, try to read it :shock:

I've only recently turned off unlimited fuel (2 days ago). :o
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Oracle427
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Re: I think I am using Pitch trim incorrectly

Post by Oracle427 »

I understand as once upon a time, I was doing the same just faf'ing around in Sublogic Flight Simulator II. I spent years of my life on that thing and worked through various generations of the software. I didn't care about anything like VORs, radios, fuel, climbs and descents, etc. I didn't even care about landing for that matter.

I just flew around and especially enjoyed the "scenery" around my home in NYC, once I discovered slew mode and made my way over there from Chicago.

https://www.youtube.com/watch?v=uCehXfpJVUA

Little by little I learned how to operate the various components, but I never truly understood what I was doing. It was always a solitary hobby for me. I had no mentor and the internet, at least as we know it today, was some time away.

I didn't pursue a career in aviation, but aviation never left me. When I could afford it and had to time I learned how to fly. I knew just where everything was in the cockpit and how to operate a lot of the analog systems. I also know a lot about the physics of flight, but I was woefully unprepared for what it took to be a pilot. I quickly got the hang of flying (not so quickly on the landings :) ), but I was definitely a long way off from being a pilot and the fact if you never ever stop learning what that means. It's one of the things I love about aviation only second to the community.
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Styggron
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Re: I think I am using Pitch trim incorrectly

Post by Styggron »

Oracle427 wrote:I understand as once upon a time, I was doing the same just faf'ing around in Sublogic Flight Simulator II. I spent years of my life on that thing and worked through various generations of the software. I didn't care about anything like VORs, radios, fuel, climbs and descents, etc. I didn't even care about landing for that matter.

I just flew around and especially enjoyed the "scenery" around my home in NYC, once I discovered slew mode and made my way over there from Chicago.

https://www.youtube.com/watch?v=uCehXfpJVUA

Little by little I learned how to operate the various components, but I never truly understood what I was doing. It was always a solitary hobby for me. I had no mentor and the internet, at least as we know it today, was some time away.

I didn't pursue a career in aviation, but aviation never left me. When I could afford it and had to time I learned how to fly. I knew just where everything was in the cockpit and how to operate a lot of the analog systems. I also know a lot about the physics of flight, but I was woefully unprepared for what it took to be a pilot. I quickly got the hang of flying (not so quickly on the landings :) ), but I was definitely a long way off from being a pilot and the fact if you never ever stop learning what that means. It's one of the things I love about aviation only second to the community.
Best post EVER. Oracle..... fantastic !!!

My story is almost identical. I still have my subLogic FSII boxed. Maps and all. I never understood much of it as I was very very little. I was saved by a youtuber called Doofer911 who makes the best tutorial videos on FSX. He introduced me to A2A and then I came here and then I could ask all my questions and thanks to the wonderful and PATIENT community here I learned a great deal.

I'm still struggling on landings and need to get out of these bad habits of flying with the trim !

I could never be a pilot, here it costs $25,000 for a PPL, I don't have the money but more importantly, I'm too dumb to be one, I would just make mistakes and then it would be bye bye.
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Re: I think I am using Pitch trim incorrectly

Post by William Hughes »

Styggron:

If I may re=phrase, you asked, "Why shouldn't I use the trim to adjust the attitude of the aircraft."

The short answer is that it is not a primary control and using it that way can have unwanted side effects in a real aircraft. Namely the long slow oscillations around the set point. It also relinquishes primary control of the aircraft to a gizmo. You won't "feel" something wrong (or right!) if you tap a button to adjust a trim setting. So that is why you fly the aircraft first, then trim off the pressure. Sometimes it matters a lot that you do it that way and you want to get in the habit of doing it that way all the time.

Having said that, at high altitudes with a wide open throttle, I have also been guilty of tapping a trim control to give it a wee nudge.

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Styggron
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Re: I think I am using Pitch trim incorrectly

Post by Styggron »

William Hughes wrote:Styggron:

If I may re=phrase, you asked, "Why shouldn't I use the trim to adjust the attitude of the aircraft."

The short answer is that it is not a primary control and using it that way can have unwanted side effects in a real aircraft. Namely the long slow oscillations around the set point. It also relinquishes primary control of the aircraft to a gizmo. You won't "feel" something wrong (or right!) if you tap a button to adjust a trim setting. So that is why you fly the aircraft first, then trim off the pressure. Sometimes it matters a lot that you do it that way and you want to get in the habit of doing it that way all the time.

Having said that, at high altitudes with a wide open throttle, I have also been guilty of tapping a trim control to give it a wee nudge.
I still use the trim to give it a slight nudge up or down. Else the only way to do it is move the joystick then realise it is too much pull back a little, re adjust and them very quickly trim to take the pressure off. It makes no sense.

If I am going to pull the joystick back a little and then quickly trim. I might as well just use the trim to get that small movement because I am going to press the trim buttons anyway so touching the joystick seems profligate. It is only going to do the same thing. These are for little little changes I'm talking about.

I would never use the pitch trim to make big changes at all.
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DC3
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Re: I think I am using Pitch trim incorrectly

Post by DC3 »

Styggron, using the trim to make a small adjustment to keep the aircraft flying level is a common practice in the real world. The reason there is so much discussion about the "use of trim" is because in the sim world sim pilots use it as a primary flight control. Here is an example where that will get you in trouble. Please note not all trouble is catastrophic. On every flight after taking off from the airport and reaching the desired altitude the pilot must push the nose down using the elevator control to level off. This will cause the aircraft to gain speed. The gain in speed will give more lift to the wings. The aircraft pilot will have to push the nose down more. In the process once the pilot has reached the desired cruise speed the power is reduced and the pilot will more than likely have to raise the nose a little. If the elevator is used through out the process the nose of the aircraft can be maintained where it needs to be and the desired altitude and speed will be quickly accomplished. Using the trim for this operation will cause the plane to oscillate about the desired altitude and make it difficult to set and maintain speed. This is because the pilot is using the trim to reacted to the up / down action of the aircraft. It will be impossible to obtain the cruise speed accurately because of the oscillation introduced by the lag of using the trim to react to the motion of the aircraft. After the throttle is adjusted and the nose is where it needs to be to maintain altitude and cruise speed all adjusted by a firm hand on the elevator control then the elevator forces can be trimmed off the control to lighten it for fine tuning the attitude of the aircraft. In relatively smooth air a little tweak of the trim here and there to keep the aircraft level is normal. In not so smooth air control using the elevator will be necessary and it will be virtually impossible to fully trim the plane before the unsettled air sends you up, or sends you down again and you have to compensate with the elevator and re-trim before the next change in air comes along. The trim is there to take the load off the controls and make the plane easier to fly with a light touch. If the pilot has to keep pulling the nose up a little tweak on the trim can fix the problem without the pilot having to pull and hold the nose up while the trim is done.

A note about altitudes in the U.S. airspace. For VFR (no flight plan, no ATC) the legal altitudes are thousands of feet plus 500 feet. So legal altitudes over a sea level area would be 3500', 4500', 5500', 6500', 7500', ... In addition to this rule a secondary legal requirement is flights with a heading 0-179 degrees must fly at odd thousands plus 500', 3500, 5500, 7500.. and flights with a magnetic heading of 180-359 degrees must fly at even thousands plus 500', 4500', 6500', 8500',... The goal is to prevent head-on crashes, or similar crashes. The philosophy is if planes are generally flying in the same direction at the same altitude they will be less likely to run into each other. For IFR traffic the same rules generally apply with eastbound traffic being kept at odd thousands of feet , 3000, 5000, 7000, 9000, ... and westbound traffic being kept at even thousands of feet, 4000, 6000, 8000, .... Of course with IFR traffic the plane is under control of ATC and may be placed at any altitude flying in any direction that ATC finds to be appropriate at the given time. When I fly around VFR (even when I use Flight Following from ATC) I follow the VFR altitude rules. If I am flying east bound and I have to pass over a mountain having an altitude of 5900 feet I will set my minimum altitude at the next higher appropriate VFR altitude which in this case would be 7500 feet. On the way back, since I will be flying westbound, I could use 6500 feet, but the puts me a little close to the terrains so I would opt for 8500 feet. A mnemonic used to remember the odd and even for the given direction is to remember that "odd" people always fly east! In the English language "odd" people are a little bit not normal in their personality which has nothing to do with why they fly east, it is just a way to remember that flying eastbound must be at odd altitudes.

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Re: I think I am using Pitch trim incorrectly

Post by AKar »

Thing that complicates the trim a bit is that in reality, it moves the primary control (actually, working through it) also. Add some, say, nose-down trim, and the elevator control jumps a bit forward, if you don't hold it still. But using it as a primary way to adjust the elevator position gets rid of the control feedback that comes through the stick normally. That's one reason why it makes sense to fly by the stick normally, outside those small adjustments having been discussed already, and when having the airplane steady, hold the stick still and relieve the pressure by using the trim.

In the simulator, this aspect is impossible to simulate precisely, as you need to move the stick while trimming whereas in reality you didn't necessarily have to (that is, without FFB in the sim).

The above doesn't apply for certain other airplanes with trimmable tailplanes: they essentially work like our controllers do, trim-wise.

-Esa

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Re: I think I am using Pitch trim incorrectly

Post by Roland Ives »

Well all that I can say is it might be a good idea to learn about slow flight. that is to transition from cruse speed 120-115 in a c172 to 90 while maintaining level flight. Yes you can trim to slow flight so you are level and hands off once you can do this try flaps 1 and 2 at 70 and trim for level flight. once you can do that then you can land with little stick by reducing the throttle only to go up or down. Once you trim for IAS all you really need is throttle to land stick is only needed to line up with center line on the runway. This is call CROSS CONTROL and if you do not master this you will never be able to fly right. there is a tutorial on slow flight on youtube by vlad the pilot and he is the best flight instructor I have ever found so go there and get you some. best of luck

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Re: I think I am using Pitch trim incorrectly

Post by Styggron »

Roland Ives wrote:Well all that I can say is it might be a good idea to learn about slow flight. that is to transition from cruse speed 120-115 in a c172 to 90 while maintaining level flight. Yes you can trim to slow flight so you are level and hands off once you can do this try flaps 1 and 2 at 70 and trim for level flight. once you can do that then you can land with little stick by reducing the throttle only to go up or down. Once you trim for IAS all you really need is throttle to land stick is only needed to line up with center line on the runway. This is call CROSS CONTROL and if you do not master this you will never be able to fly right. there is a tutorial on slow flight on youtube by vlad the pilot and he is the best flight instructor I have ever found so go there and get you some. best of luck
Hello Roland,
I shall do that. Doofer911's youtube channel has the best FSX flight tutorials. He has one on slow flight, I shall have a look at that.
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Re: I think I am using Pitch trim incorrectly

Post by Oracle427 »

Roland Ives wrote:Well all that I can say is it might be a good idea to learn about slow flight. that is to transition from cruse speed 120-115 in a c172 to 90 while maintaining level flight. Yes you can trim to slow flight so you are level and hands off once you can do this try flaps 1 and 2 at 70 and trim for level flight. once you can do that then you can land with little stick by reducing the throttle only to go up or down. Once you trim for IAS all you really need is throttle to land stick is only needed to line up with center line on the runway. This is call CROSS CONTROL and if you do not master this you will never be able to fly right. there is a tutorial on slow flight on youtube by vlad the pilot and he is the best flight instructor I have ever found so go there and get you some. best of luck
Agree with everything said above except for the definition of cross control. Cross Control refers to when one applies rudder and aileron in opposite directions to put the aircraft into a sideslip in order to align the aircraft with its flight path instead of crabbing into the wind. It can also be used in a greater forward slip application to increase drag to descend faster in a given distance. It is also a technique used to keep an aircraft aligned longitudinally as well as flying over the runway centerline in a crosswind before touchdown. The key here is to slip and not skid the aircraft. The rudder should be applied away from the bank and not into the bank. If a stall were to occur, the former (slip) is an anti-spin input and the latter (skid) is pro-spin.
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Roland Ives
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Re: I think I am using Pitch trim incorrectly

Post by Roland Ives »

Sorry but I am sure that Cross control is cross control and a slip is a slip they are two different things. Please do not take offense. in cross control the elevator is used to control speed and the throttle is used to go up or down hence the name cross control Thank you

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Re: I think I am using Pitch trim incorrectly

Post by Great Ozzie »

Roland Ives wrote:Sorry but I am sure that Cross control is cross control and a slip is a slip they are two different things. Please do not take offense. in cross control the elevator is used to control speed and the throttle is used to go up or down hence the name cross control Thank you
Hey Roland,

Oracle is correct. Rudder in one direction and aileron in the other is cross-controlling. Let me give you a couple examples from the Airplane Flying Handbook.

A cross-control stall occurs when the critical AOA is exceeded with aileron pressure applied in one direction and rudder pressure in the opposite direction, causing uncoordinated flight. A skidding cross-control stall is most likely to occur in the traffic pattern during a poorly planned and executed base-to-final approach turn in which the airplane overshoots the runway centerline and the pilot attempts to correct back to centerline by increasing the bank angle, increasing back elevator pressure, and applying rudder in the direction of the turn (i.e., inside or bottom rudder pressure) to bring the nose around further to align it with the runway.

Most airplanes exhibit the characteristic of positive static directional stability and, therefore, have a natural tendency to compensate for slipping. An intentional slip, therefore, requires deliberate cross-controlling ailerons and rudder throughout the maneuver.

Glossary
Cross controlled. A condition where aileron deflection is in the opposite direction of rudder deflection.

-Rob
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Oracle427
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Re: I think I am using Pitch trim incorrectly

Post by Oracle427 »

I'm can't recall if there is a specific term to describe the practice of pitching for airspeed and using power to control altitude. Certainly a good practice when at the cusp of or on the back end of the power curve!
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Re: I think I am using Pitch trim incorrectly

Post by Great Ozzie »

Oracle427 wrote:I'm can't recall if there is a specific term to describe the practice of pitching for airspeed and using power to control altitude. Certainly a good practice when at the cusp of or on the back end of the power curve!
Me either. It's one of those things... like a Geico commercial... if you're a pilot, it's what you do. :)
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Re: I think I am using Pitch trim incorrectly

Post by Great Ozzie »

Roland Ives wrote:in cross control the elevator is used to control speed and the throttle is used to go up or down hence the name cross control
Roland,

I found something almost word for word from your quote except the "cross control" part, so I thought I would post it here. It's out of Stick & Rudder. I am still not sure where this idea of "cross control" is coming from.
-------

Your Real Elevator is your Throttle!

As for going up, there is really only one thing that will ever make an airplane go up, and that is engine power; you can make it go up temporarily by ballooning it with your elevator, but only engine power can make it go up and stay up; and hence your up-and-down control is the throttle. If any part of the airplane deserves the name of "elevator" it is the throttle.

All this is not nearly so "theoretical" as it sounds. You can demonstrate to yourself that this is really the way an airplane's controls fly. In some airplanes, certain effects (...) will make the demonstration a bit unconvincing. A particularly suitable airplane is the side-by-side Taylorcraft -- partly because it behaves especially well in this respect, and partly because the control arrangement makes it easy to arrest the elevator in any desired position; simply pinch the control shaft with your fingers where it comes out of the instrument board. your other hand can then still work the wheel for aileron control, but with the elevator thus arrested, you can vary your throttle at will, and you will see that the throttle is what gets you up or down, and that the so-called "elevator" controls the speed.

Fwiw,
Rob

Edit:

Not sure if you can see this article Cross-Coordinated on cross-controlling (Aviation Safety - April 2006) but it is a good article. Cross-controlling is often necessary to maintain coordinated flight, but it can be dangerous. It’s not whether you cross the controls, but how and when.
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