Starting in training with Cessna : AOA bip and plane falling down

[Ewsg]

Hi there,

 

First of all, thank you very much for accepting me in this forum. Also, sorry if this is not the correct place to start this thread.

 

Well, I would like to know if someone could help me here in Microsoft Flight Simulator, please.

 

I am almost desperate, because in the middle of the training sessions/tutorials, I can't fly anymore. I am in that first VFR solo flight. And here, after taking off, my plane falls down. I don't know what is happening, but while I try to gain altitude, a bib begins to sound.

 

If I change to the external view, I can see an indicator mentioning AOA. I could even see that this is the angle of attack, but this is everything I understood.

 

Now, also it seems I "unlearned" everything I learnt: because even in the first missions my plane, the Cessna, is falling down, no matter what I do.

 

I am playing using a Thrustmaster Hotas, but this is my first time with a flight simulator. I don't know what is happening, neither why is that AOA bit sounding a lot when I try to get higher.

 

Anyone could help me, please? I would be extremely grateful.

 

Below is a screenshot of one of my bad times, which I think shows what is happening here:

 

https://imgur.com/kkMQR0r

[Nels_Anderson]

"AOA' means "angle of attack", referring to the angle at which the airplane is trying to climb. A positive number means the nose of the plane is higher than the tail.

 

In your screen shot your AOA is shown as 12 degrees and though it's partially covered it looks like your airspeed is almost zero.

 

So, what has happened is that you have stalled. Because the angle is too steep the speed has gotten so slow that the wings are no longer generating lift, and so down you go.

 

Unless there is something set wrong (i.e., you joystick or yoke settings/calibration), the fix is simply not to pull back on the stick as much. At this point, your airspeed should probably be around 60 or 70 so lower the nose until you get at least that.

 

I also see that you are at a very high altitude airport. Engine performance declines with altitude, so if you practiced at a sea level airport instead of an airport at 7000 feet you'd have more power and lift and it would be harder to stall.

[Ewsg]

Hi @Nels_Anderson,

 

I am very grateful for your support and kindness. Thank you so much.

 

And sorry for posting this kind of question. I was just a bit desperate because nothing seemed to work.

 

But reading your post I began to understand things a bit more. I have not changed anything in the Hotas settings, but maybe I need to calibrate it. I'll try to see that.

 

Also, I think I was pulling the stick too much. If I remember well, it was at those moments the plane was starting to fall. Now I tried to be more gentle here, and I got to maintain the plane on airr, despite having to do a couple of "curves".

 

I'll try to follow everything you said in a couple of moments. Many thanks once again, and sorry for the disturbance.

[Nels_Anderson]

Nothing to apologize for, asking questions is why we have these forums.

 

Yes, you likely were pulling back to the stick too much. Next time get the speed up to about 60 before trying to lift off and then hold the stick such that the airspeed is around 70 to 80. At full power and that airspeed you should get a normal rate of climb, somewhere in the 500 to 1000 feet per minute range and will maintain good control of the plane.

[Ewsg]

 Thank you so much. Much appreciated.

 

I'm currently struggling to reach the speed of 75 knots whiling trying to climb and reach 8500 feet. The speed simply does not grows up.

 

My speed never surpasses 40 - 50, and in that tutorial mission I am failing because I reach a point very far from the airport (and this training mission asks us to reach 75 knots).

 

Also, I am constantly hearing that AOA bip and having to maintain a low altitude due to that. Do you know if that first Cessna we flight in the training center has some kind of instrument through which we can see the AOA, so we can maintain the cockpit view instead the external view?

 

Well, I will also try to follow your last tips, hope I get that tonight.

[NFM]

2 hours ago, Ewsg said:

I'm currently struggling to reach the speed of 75 knots whiling trying to climb and reach 8500 feet. The speed simply does not grows up.

The Cessna 152 has throttle (black), propeller (blue) and mixture (red) control. Normally all three levers should be on maximum for take-off. If one of them isn't, this will reduce your available power drastically.
 

 

2 hours ago, Ewsg said:

Also, I am constantly hearing that AOA bip and having to maintain a low altitude due to that. Do you know if that first Cessna we flight in the training center has some kind of instrument through which we can see the AOA, so we can maintain the cockpit view instead the external view?

Some airplanes have AOA indicators in the cockpit. They look pretty much the same as the AOA instrument in the external view. But I don't think that the Cessna 152 has one in MSFS. 
Instead I would you use the artificeal horizon (the instrument that is usually brown and blue). It shows you the AOA and your bank angle. 

[Nels_Anderson]

OK, so one big issue I see is altitude. Standard aircraft engines lose power as altitude increases, because the air gets thinner. An engine turns air combined with fuel into energy, and with less air available the engine's ability to create power decreases. To make things worse, the thinner air also means your wings generate less lift.

 

So to reach 75 knots at 8500 feet you will need a very gentle climb rate, pulling back the stick very little. So once off the ground, adjust the stick position so that you first reach 75 knots (even if you are not climbing much) and once there see if you can pull back a bit more and get more climb. Your engine can either make you go fast, or go up, so you use the stick to adjust how much fast vs. up you get.

 

I'm not really familiar with that particular plane, but the AOA beep is probably the stall warning. Planes I'm familiar with will beep when your airspeed is getting low to the point where you are near stalling.

 

AOA can be read from the artificial horizon instrument that is usually right in the middle of the panel in front on you. But as a beginner you should mostly keep your eyes out the window, and with practice can get the same information just by comparing the height of the nose of the plane versus the horizon in front of you.

[Mike80]

1 hour ago, NFM said:

The Cessna 152 has throttle (black), propeller (blue) and mixture (red) control. Normally all three levers should be on maximum for take-off. If one of them isn't, this will reduce your available power drastically.
 

 

Some airplanes have AOA indicators in the cockpit. They look pretty much the same as the AOA instrument in the external view. But I don't think that the Cessna 152 has one in MSFS. 
Instead I would you use the artificeal horizon (the instrument that is usually brown and blue). It shows you the AOA and your bank angle. 

The Cessna 152 does not have a constant speed prop, so no"blue knob" in the cockpit. 

The artifical horizon does not indicate AoA - it indicates aircraft pitch angle from the horizon, though it can be a loose correlation at times.

 

Do you may have a dual scale airspeed indicator with two concentric scales, one for knots, one for miles per hour - if you do, make sure you are using the correct one all the time, it can get confusing.

 

Also, are you withi maximum takeoff weight?? Are you using full throttle?

 

Looking at a 152 handbook on line I see:

Climb, Flaps Up: Normal .................  70-80 KIAS

Best Rate of Climb, Sea Level ........ 67 KIAS

Best Rate of Climb, 10,000 Feet ..  61 KIAS

 

so at 8500 ft MSL your climb speed at full power should be about 62 - 63 KIAS (71 - 72 mph), not 75 KIAS

 

I do not have MSFS, but in FSX and P3D there is an auto-lean choice to use in OPTIONS settings. Depending on how sophisticated a given model is, either manual leaning with altitude or autolean is required to get maximum power during a climb. Anyone know how MSFS uses this??

 

[pzl 104]

8 minutes ago, Mike80 said:

The Cessna 152 does not have a constant speed prop, so no"blue knob" in the cockpit. 

The same usually goes for 172s.

 

My airplane art:

Bernt Stolle - Art for Sale | Fine Art America

  

[pzl 104]

1 hour ago, NFM said:

Instead I would you use the artificeal horizon (the instrument that is usually brown and blue). It shows you the AOA and your bank angle. 

Where do you see the AoA on the artificial horizon?

 

My airplane art:

Bernt Stolle - Art for Sale | Fine Art America

[nsproles]

Your image is difficult to interpret, but it seems as if your flaps are retracted.  You should have flaps one for take off and keep them there until you are well up and flying.  The ground elevation being what it is, you should be climbing at around 400 - 500 fps at around 63 knots.  Are you adjusting your engine for mixture?  At those altitudes, you may be running too rich and losing power while wasting fuel . Pull the mixture control gently in and out until you get maximum RPM.  Are you at full throttle - the image indicates that you may not be.  Is your aircraft trimmed so that it is not excessively nose up and so tending to stall?  You can tell when you are correctly trimmed as you don't have to apply pressure on the stick.  Try taking off and flying straight and level for a while, build up speed, then pull the stick back gently and see how you climb and at what speeds.  The Cessna 152 (?) is no F35 when it comes to climbing so don't expect to have it snap your neck back. 

[Ewsg]

Hi guys,

 

I would like to thank you all for all the help and kindness.

 

MSFS is the first flight sim I play, and so I am struggling a bit.

 

I confess that somethings you said I don't understand very well yet, but I am annotating everything in order to continue studying and learning.

 

Tonight I'll do that flight lessons again and hope to be able to take off accordingly, using all the information and tips provided through this thread.

 

Trim, moreover, is something I am not using yet, and I know I need to take a look on this and start to use.

 

Thanks once again, to all of you.

[pzl 104]

Just checked your screenshot.  For training I strongly suggest you choose an airport at or close to Sea Level.

 

7000ft airport elevation is a lot for a piston engine and it means a significant power reduction.

Furthermore you need to lean the engine a lot in the sim (which is not very realistic) to reduce the loss of performance due to the high altitude.

 

You don't need any flaps on a Cessna 152 or 172 for take off!  They help decrease the take off run, but they decrease climb performance!

 

Trimming is essential and the correct technique is quite easy.

If you e.g. need to push the yoke constantly forward to maintain your desired pitch attitude, you start trimming nose down.

The more trim you apply, the less forward pressure on the yoke is required.

You repeat trimming in small steps until you can let go of the yoke without any change of pitch attitude.

That said, MSFS does a pretty bad job concerning plane stability when trimming. It's way easier IRL.

 

My airplane art:

Bernt Stolle - Art for Sale | Fine Art America

 

[ViperPilot2]

Parking Brake ON

FLAPS to FIRST Position.

Throttle to FULL, and WAIT until the RPM Gauge reaches its Maximum point.

RELEASE Parking Brake.

Your Airspeed Indicator MUST be in the WHITE (50 KTS or More) before you can even think about pulling back on the Stick/Yoke.

At 60 KTS, pull back on the Stick until the V. Speed Indicator reads +300 Feet. DO NOT EXCEED THIS AMOUNT.

STAY AT +300' with the V. Speed Indicator until you build up speed to 70 KTS and 500' Above Ground Level (AGL).

RAISE Flaps. You will start to Sink (fall), so compensate by pulling back on the Stick to maintain the +300' on the V. Speed Indicator.

PULL the RED Knob out slightly. Keep the Throttle at FULL.

Build up some Airspeed until you get to 80 KTS. DO NOT EXCEED +500 FEET ON YOUR CLIMB.

 

(OP @ Field 7000' ASL in a C-150/152. HIGH DA. He's gotta pour the Coal on to get to V1. Rotate and stay in Ground Effect @ +300 AGL to build up Airspeed, then Flaps Up & Adjust Mixture).

[pzl 104]

@ViperPilot2 Is there a reason why you recommend to use flaps for take off? 

IF you use flaps, initial climb should be 54kts, flap retraction 60kts and the climb speed at 7000ft with flaps up should be 68-73kts.

Furthermore you need to lean the mixture a lot already before starting the takeoff run. 

 

@Ewsg  If you stay at this airport, I suggest you apply the parking brake and apply full throttle before starting the takeoff run.

Note the maximum RPM. Then start pulling back the red mixture knob and watch how RPM starts increasing.

Keep pulling the mixture lever back until RPM starts dropping again and push it in again until you achieve max RPM again. 

 

My airplane art:

Bernt Stolle - Art for Sale | Fine Art America

[Ewsg]

@pzl 104,

 

So, is that I am doing that training sessions. I think it's impossible to choose the airport there, isn't it? Or do you recommend to not use the training center and instead try to learn doing "real" flights, through the world map?

 

About trimming, I got to identify the keys through which I can use it, but I am still trying to understand its usage.

 

One thing I need to understand is how to properly use that mixture knob. I know it's probably something simple, but as I am new to everything of this, things tend to be a bit more complicated.

 

I just don't understood very well why these pulls and pushes.

 

@ViperPilot2

 

I was not using the parking brakes at the beginning. Yesterday I started to use them and everything changed a lot.

 

---

 

Well, once again, thank you so much, guys. Sorry for the large amount of noob questions. I am just trying to understand all these things.

 

Yesterday night, moreover, I got to successfully take off. I am now struggling while trying to find locations. I need to reach another airport in VFR, but that course/heading indicator seems to not be really useful. At least for now, and for me.

[pzl 104]

That was one of MS/Asobos very weird ideas to choose an high altitude airport for training, but with correct leaning this shouldn't be a problem.

Maybe in the realism settings auto mixture is already enabled and your plane performs already realistic. 

If you pull the mixture knob towards you and there's no RPM change, auto mixture is enabled and you can forget about it.

I would recommend using auto-mixture in any case, since this is still more realistic than the broken leaning engine, plus you don't have to fiddle with the red mixture knob.

 

No keys for trimming!  IRL the hat switch is used for trimming. If it's not assigned you should do that.

Push the hat forward/up to trim nose down and pull the hat back/down to trim the nose up.

That way you have to immediate feedback about the correlation between stick pressure and trim effect.

Note that trim response is a bit sluggish. You trim a bit nose up/down, wait a bit, continue trimming, wait a bit and so on, until you can let go of the joystick.

 

 

[Ewsg]

I just checked settings and auto mixture is enabled. But I was trying to play with it before, and noticed variations on RPM while I was pushing or pulling the knob. Very little variations.

 

I also checked settings and noticed that trim is set to the buttons 5 and 6 of throttle (I use a Thrustmaster T.flight Hotas). So maybe I need to change this to the hat switch.

 

The problem is that the hat switch currently is in use for the camera/view (I use it to look left, right, to see the panel, etc). Well, let's keep trying. Thank you very much!

 

 

[pzl 104]

 

Great that auto mixture is enabled. Keep it that way.

 

Trim should be defintitely on the stick, not the throttle.

 

Instead of the hat switch you can use the two buttons near the hat switch for trimming.

E.g. the button to the left/right of the hat to trim down, and the center button below the hat switch to trim up.

 

For the brakes I use the trigger. Park brake is a key assignment on my setup.

 

 

 

[nsproles]

14 hours ago, Ewsg said:

 

 

One thing I need to understand is how to properly use that mixture knob. I know it's probably something simple, but as I am new to everything of this, things tend to be a bit more complicated.

 

I just don't understood very well why these pulls and pushes.

 

The mixture knob determines the air-to-fuel ratio.  Your aim is to get that ratio of fuel to air that will burn all the fuel.  Too much fuel, ie a 'rich mixture', and you are wasting fuel; too low an amount of fuel, ie  a 'lean mixture', and you are not developing power.  In real life, incorrect mixture control can damage the engine.  As you gain altitude, the amount of air available lessens so you need to reduce the amount of fuel in the mixture in order to maintain a proper air-to-fuel ratio.  As you descend, the reverse applies.  The best ratio for aviation piston engines is in the order of 15 parts of air to one part fuel.  You control this by pushing or pulling the mixture knob as explained above.  Pulling leans, pushing richens.  Back in the days before computers, you had to do something similar with your car, especially when starting on cold mornings.  Controlling the mixture yourself just adds to the realism of the simulator.  There are plenty of good articles on this topic on YouTube as well as articles on other aspects of using MSFS.

[pzl 104]

@nsproles Nice explanation, but you should add that the mixture simulation in MSFS has almost nothing to do with leaning IRL.

E.g. how much you have to lean, the fuel flow increase when leaning and the leaning effect on performance, everything is way off and partially even the opposite of how leaning works IRL.

Auto mixture is unfortunately still the most realistic choice.

 

[Ewsg]

@pzl 104

 

That's really great. I will leave it as it is.

 

I also set trim to that buttons you suggested, near the hat switch. I confess it's being a little difficult to use trim, but I still trying.

 

I now get to take off successfully. I just find some problems while trying to gain altitude and maintain speed. But I know that here I have to combine somethings you all suggested, and I still trying and practicing.

 

@nsproles

 

Amazing explanation! Thank you so much!

 

I will leave auto mixture enabled for now, and as I gain experience I'll start playing with it.

 

Well, I'll play with several settings as well.

 

I am now a little more comfortable with somethings, and starting to appreciate the experience a lot.