Slowing Down and Landing

[Caldera]

Hey All,

Go easy, I am a new pilot here and not a whole lot of sim rotary wing experience.  I bought the UH-1H module so that I could practice for another rotary wing module that I have pre-purchased.  Still waiting...

I think that I have a handle on VRS (and crashing), entry and exit to and from translational flight.  But, I do not get a couple of things.  Other than YouTube (Casmo among others), I am self taught.  So maybe I am doing it wrong.

As I am coming in for landing I am working the forward trim off as I descend.  I suppose that I am in sort of an auto-rotation mode, but with more collective angle.  As I slow down, descend and re-add collective I also have to start adding right pedal.  The faster this happens the more right pedal I have to add.  If I go too fast then I am pushing almost full right pedal.  Is this correct?

As I slow down for landing I try to be pretty close to being inside ground effect by the time I get below 40 knots.   If this happens when I am too high then I try to go into an outside ground effect hover and lower myself down slowly. 

But I notice something kind of weird happening.  I find it somewhat hard to slow down to 40 knots.  It takes me awhile to do that.  As soon as I go below 40 knots its like the Huey hits a truck runaway ramp of some kind.  The rate of speed decrease goes way up.

So typically, as I am gliding down using more and more right pedal.  Then I go below 40 knots and the thing hits the brakes and speed drops rapidly to, lets say, 20 knots along with some dash shaking.  Now I have to slam the left pedal or it starts a merry-go-round routine.  Is this correct?

It does not make sense to me that this is the way it should be as it sets up for quite a bit of instability going rapidly from right pedal to left pedal, but I am uncertain.

Thanks in advance,

Caldera

[Frederf]

You get some yaw stability from forward speed over the helicopter. Right pedal is required when using a lot of collective and not having a lot of airflow. Coming to a hover-halt is exactly that sort of situation. During horizontal flight above ~40mph you're reducing the lift required compared to hover. This is called effective translational lift (ETL). While hovering the air sets up a cyclone going down from the rotor, around, and back through. Hovering requires extra lift as the helicopter is effectively in a downdraft.

Qualitatively it is normal for transitioning to a hover to require a distinct increase in collective required as you lose ETL. This increase in collective causes more yaw torque which requires more right pedal to counter. If the particular magnitudes you are experiencing are correct I can't say but it is realistic in principle.

One way to make this transition require less collective (and thus less pedal) is to change from ETL to hover while in ground effect. Being near the ground disrupts the circular flow of air around the rotors which makes the collective required less drastically different between >40mph and hover. As collective required is not as different the pedal required making the change will be less drastic too.

[admiki]

4 hours ago, Frederf said:

You get some yaw stability from forward speed over the helicopter. Right pedal is required when using a lot of collective and not having a lot of airflow. Coming to a hover-halt is exactly that sort of situation. During horizontal flight above ~40mph you're reducing the lift required compared to hover. This is called effective translational lift (ETL). While hovering the air sets up a cyclone going down from the rotor, around, and back through. Hovering requires extra lift as the helicopter is effectively in a downdraft.

Qualitatively it is normal for transitioning to a hover to require a distinct increase in collective required as you lose ETL. This increase in collective causes more yaw torque which requires more right pedal to counter. If the particular magnitudes you are experiencing are correct I can't say but it is realistic in principle.

One way to make this transition require less collective (and thus less pedal) is to change from ETL to hover while in ground effect. Being near the ground disrupts the circular flow of air around the rotors which makes the collective required less drastically different between >40mph and hover. As collective required is not as different the pedal required making the change will be less drastic too.

You probably mean left pedal, but rest is spot on.

 

5 hours ago, Caldera said:

Hey All,

Go easy, I am a new pilot here and not a whole lot of sim rotary wing experience.  I bought the UH-1H module so that I could practice for another rotary wing module that I have pre-purchased.  Still waiting...

I think that I have a handle on VRS (and crashing), entry and exit to and from translational flight.  But, I do not get a couple of things.  Other than YouTube (Casmo among others), I am self taught.  So maybe I am doing it wrong.

As I am coming in for landing I am working the forward trim off as I descend.  I suppose that I am in sort of an auto-rotation mode, but with more collective angle.  As I slow down, descend and re-add collective I also have to start adding right pedal.  The faster this happens the more right pedal I have to add.  If I go too fast then I am pushing almost full right pedal.  Is this correct?

As I slow down for landing I try to be pretty close to being inside ground effect by the time I get below 40 knots.   If this happens when I am too high then I try to go into an outside ground effect hover and lower myself down slowly. 

But I notice something kind of weird happening.  I find it somewhat hard to slow down to 40 knots.  It takes me awhile to do that.  As soon as I go below 40 knots its like the Huey hits a truck runaway ramp of some kind.  The rate of speed decrease goes way up.

So typically, as I am gliding down using more and more right pedal.  Then I go below 40 knots and the thing hits the brakes and speed drops rapidly to, lets say, 20 knots along with some dash shaking.  Now I have to slam the left pedal or it starts a merry-go-round routine.  Is this correct?

It does not make sense to me that this is the way it should be as it sets up for quite a bit of instability going rapidly from right pedal to left pedal, but I am uncertain.

Thanks in advance,

Caldera

You are correct in your observations. It was pointed long time ago that Huey likes to lose speed a little bit to fast, but you will learn to cope with more experience.

Way to reduce your pedal switch is to make shallower approach with more collective than you are using now. This will then benefit in less power change at the end of your approach.

[Caldera]

Thanks Guys,

OK...

So for landing I have been coming in at 40-60 knots and dropping at probably around 500 FPM.  To stay coordinated I find that I have to add more and more right pedal.  At times I am at or close to full right deflection on my rudder pedals.  This doesn't seem quite right to me because I just about lose all ability to rotate any more to the right, all the effort just goes into flying coordinated.   

I get the part about left pedal counter thrust below ETL, but that is less than 50% of how much right pedal I am adding at 40 kts.  I am using a straight curve on my rudder pedals.

I do not have a good feel for descent angles so I use forward speed and vertical air speed as my guide.  What descent FPM and forward speed should I shoot for?

 

Also the dang pilot trimmer causes me some issues.  If I do not use the trimmer then my joystick becomes a beast to hold in position.  I have the weakest springs and a cosmo cam installed.  The biggest hindrance seems to be how coarse the Cyclic controls are.  I am using the ones in the picture below.

J

Just a quick flip of the switch can cause pretty severe gyrations to occur due to how much the trimmer effects control.  Is there a way to tone down how much these controls effect the pilot trimmer or are there other controls some where else for finer control?

 

Maybe use another joystick with no springs installed?

Caldera

[Zap921]

I have no springs in my X56 and love it.  Wish it had a longer extension on it because it is way to sensitive compared to real life inputs and I find that curves don't really work so well.  I also don't use the trim function as it seems to work or not work the same in different modules.  Try learning takeoff/landings without using the trim to start.  You could try posting a video of an approach/landing which will point everyone in the right direction to help you.  Start your decent farther out, there's no reason you can't fly at 60kts / 500agl and land pretty easily.  

[admiki]

37 minutes ago, Caldera said:

Thanks Guys,

OK...

So for landing I have been coming in at 40-60 knots and dropping at probably around 500 FPM.  To stay coordinated I find that I have to add more and more right pedal.  At times I am at or close to full right deflection on my rudder pedals.  This doesn't seem quite right to me because I just about lose all ability to rotate any more to the right, all the effort just goes into flying coordinated.   

I get the part about left pedal counter thrust below ETL, but that is less than 50% of how much right pedal I am adding at 40 kts.  I am using a straight curve on my rudder pedals.

I do not have a good feel for descent angles so I use forward speed and vertical air speed as my guide.  What descent FPM and forward speed should I shoot for?

 

Also the dang pilot trimmer causes me some issues.  If I do not use the trimmer then my joystick becomes a beast to hold in position.  I have the weakest springs and a cosmo cam installed.  The biggest hindrance seems to be how coarse the Cyclic controls are.  I am using the ones in the picture below.

J

Just a quick flip of the switch can cause pretty severe gyrations to occur due to how much the trimmer effects control.  Is there a way to tone down how much these controls effect the pilot trimmer or are there other controls some where else for finer control?

 

Maybe use another joystick with no springs installed?

Caldera

You are using trim wrong. Huey does not have trim hat, just force trim. You need to set it in options, you get your stick in desired position, press trim release (or press and hold, depending on your settings) and return stick to center and then you don't have to fight springs. Are you by any chance using control helper? There is no need for that much right pedal unless you are coming down in autorotation

[Caldera]

Hey Guys,

Sorry for taking so long to get back.  I had issues with my joystick and I ended up doing about a 100% reconfigure.

I am learning to adapt better, but I still have not solved my yaw issue.  My landings are generally controlled...

 

This first picture has no pedal input.  (well maybe a little, my left foot must be a tad fatter than my right foot)

This second picture does have pedal input.  To maintain co-ordinated flight I am adding quite a bit of right pedal.

Should I just ignore the yaw?

Caldera

Edited February 3, 2022 by Caldera

[Zap921]

I just made two approaches after seeing your reply.  Both approaches were made at approximately the same rate of decent and IAS.  I have to use very little right pedal and I mean very little to keep the nose straight ahead, the ball is centered but this is not what I'm looking very much on an approach/landing.  I use about 1/2 left pedal leaving the ground on takeoff to keep the aircraft straight, fyi, not sure what your chopper takes and this is all dependent on temp, your load at takeoff.  

[DishDoggie]

I turn the Trim Switch off when I fly: Question Does Anyone Else Do This? I never Set a Trim up When I fly. I just Don't Need it. So Why should I use it or Tell me Why you feel I am doing it Wrong. I feel like it is not needed. I understand What He is asking When I try to land on a Oil Rig I get the same Effects I'm High in the air No Ground under me so the Need for Hard Right Peddle is needed. I like to keep myself in the Transition when My Dash is Shaking I keep it there and ride it in as long as I can and My Collective is Always on the move  up and down Small Micro Movements till I get a Smoother transition into a very slow forward hoover I control up down or forward to landing. I fly by the Seat of the Pants. Self Taught I admire you that dig in and teach yourself all the Physics and Knowledge end of it Deep Respect to you but I need to get hands on and figure it out till I feel I an Dam Good at it.

Force Trim System

Force centering devices are incorporated in the cyclic controls and directional pedal controls. These devices are installed between the cyclic stick and the hydraulic servo cylinders, and between the anti-torque pedals and the hydraulic servo cylinder. The devices furnish a force gradient or "feel" to the cyclic control stick and anti-torque pedals. A FORCE TRIM ON/OFF switch is installed on the miscellaneous control panel to turn the system on or off. These forces can be reduced to zero by pressing and holding the force trim push-button switch on the cyclic stick or moving the force trim switch to OFF.

 

From the Pages of:

https://www.digitalcombatsimulator.com/en/products/helicopters/huey/?PAGEN_1=3#:~:text=Force Trim System,-Force centering devices&text=A FORCE TRIM ON%2FOFF,force trim switch to OFF.

[markturner1960]

On 1/31/2022 at 12:24 PM, Caldera said:

Thanks Guys,

OK...

So for landing I have been coming in at 40-60 knots and dropping at probably around 500 FPM.  To stay coordinated I find that I have to add more and more right pedal.  At times I am at or close to full right deflection on my rudder pedals.  This doesn't seem quite right to me because I just about lose all ability to rotate any more to the right, all the effort just goes into flying coordinated.   

I get the part about left pedal counter thrust below ETL, but that is less than 50% of how much right pedal I am adding at 40 kts.  I am using a straight curve on my rudder pedals.

I do not have a good feel for descent angles so I use forward speed and vertical air speed as my guide.  What descent FPM and forward speed should I shoot for?

 

Also the dang pilot trimmer causes me some issues.  If I do not use the trimmer then my joystick becomes a beast to hold in position.  I have the weakest springs and a cosmo cam installed.  The biggest hindrance seems to be how coarse the Cyclic controls are.  I am using the ones in the picture below.

J

Just a quick flip of the switch can cause pretty severe gyrations to occur due to how much the trimmer effects control.  Is there a way to tone down how much these controls effect the pilot trimmer or are there other controls some where else for finer control?

 

Maybe use another joystick with no springs installed?

Caldera

Am I understanding correctly from that screen shot you are not using the cyclic as an axis, but instead using buttons to move it left ,right forward, back etc? 

[Calabrone]

I don't use Force Trim anymore and I feel great, much better than when I used it.

[Zap921]

I never used Force Trim in DCS or X-Plane. Then again I took the spring out of my X56 cyclic controller.  I could see where it would be useful instead of fighting the spring pressure constantly.

[Calabrone]

2 hours ago, Zap921 said:

I never used Force Trim in DCS or X-Plane. Then again I took the spring out of my X56 cyclic controller.  I could see where it would be useful instead of fighting the spring pressure constantly.

I have tried with my T16000M but it becomes ungovernable. I'm thinking of looking for a less stiff pedal spring, but time is a bastard.

[Zap921]

I'm using the Logitech/Saitek Pro flight pedals and I also did the spring mod on those so they remain whatever position they're in when I remove my feet. 

[Calabrone]

29 minutes ago, Zap921 said:

I'm using the Logitech/Saitek Pro flight pedals and I also did the spring mod on those so they remain whatever position they're in when I remove my feet. 

My pedals would only be fine if the spring was less stiff, because I have a hard time holding it in place and it has too much hard and fast return. So I end up getting tired in my legs.

[Czech6]

I'm late to this conversation, but I agree with markturner1960.  It appears that you have the cyclic set as button presses and not on an axis.  If your anti-torque pedals are also set as button presses that may be your problem.  Select the Axis category and calibrate your controls on an axis and not button presses.  I would imagine that those button presses are a single press and not continuous.

[Dogmanbird]

just a heads up for x55/x56, Warthog, T16000/Airbus (and Saitek/Logitech pedal users) if not already aware, they have a small centre deadzone of a few degrees programmed into the firmware. Unfortunately it can't be removed in their setup/calibration software. Unless you're using an extension of some kind you may not be aware of it. The longer the extension the more noticeable it is

[uniform]

On 1/31/2022 at 2:20 AM, admiki said:

You probably mean left pedal, but rest is spot on.

 

You are correct in your observations. It was pointed long time ago that Huey likes to lose speed a little bit to fast, but you will learn to cope with more experience.

Way to reduce your pedal switch is to make shallower approach with more collective than you are using now. This will then benefit in less power change at the end of your approach.

Thanks, that helped my landings dramatically. It does not help I started flying simulated Helo's in MS Flight Simulator which states, that the program is not a Helo sim and that some functions are automated.

I am curious if this is the reason why in Vietnam war movies (or any movie filming a UH-1H landing) they come in at shallow angles to the Earth with their bodies tilted way back. That has become an Icon of the UH-1H and makes for a dramatic landing IMO.

[Xupicor]

On 8/6/2022 at 4:52 PM, Dogmanbird said:

just a heads up for x55/x56, Warthog, T16000/Airbus (and Saitek/Logitech pedal users) if not already aware, they have a small centre deadzone of a few degrees programmed into the firmware. Unfortunately it can't be removed in their setup/calibration software. Unless you're using an extension of some kind you may not be aware of it. The longer the extension the more noticeable it is

I've seen this posted a few times, but I own a Warthog and do not notice any baked in deadzone (much less of a "few degrees") with it, and I do have an extension of 20cm.

Maybe this was fixed in a newer firmware? Any source for that claim to begin with? 

[Dogmanbird]

Hi Xupicor,

I have have the warthog joystick / throttle and bought them around 2014. I haven't tried updating firmware so you are possibly right that it's been fixed since. Back then I was unable to remove it even though the software showed that it was set to 0. A colleague's stick of similar age did the same thing.

 

[MAXsenna]

23 hours ago, Xupicor said:

I've seen this posted a few times, but I own a Warthog and do not notice any baked in deadzone (much less of a "few degrees") with it, and I do have an extension of 20cm.

Maybe this was fixed in a newer firmware? Any source for that claim to begin with? 

I read a post somewhere on another forum, that had a link to some software you could check and remove firmware deadzones. I couldn't find any in any of my sticks. And I had never noticed any either.  

[RodBorza]

On 2/3/2022 at 2:29 PM, Caldera said:

Hey Guys,

Sorry for taking so long to get back.  I had issues with my joystick and I ended up doing about a 100% reconfigure.

I am learning to adapt better, but I still have not solved my yaw issue.  My landings are generally controlled...

 

This first picture has no pedal input.  (well maybe a little, my left foot must be a tad fatter than my right foot)

This second picture does have pedal input.  To maintain co-ordinated flight I am adding quite a bit of right pedal.

Should I just ignore the yaw?

Caldera

 

Approach speeds: Vertical speed, as per the pictures shown on the post, must be below -500 ft/min. No more than that. Otherwise you will fall out of the sky. 

Regarding forward speed, less than 40 mph. It is trick though on the Huey, because below 40 knots you lose lots of lift, and below 20 knots you lose even more. I usually come at 40 knots, and then, close to the ground I reduce to 20 knots, then it is all visual from there, because below 20 knots, the pitot tube is not reliable to tell you the speed that you are travelling. For touch down, vertical speed must be around -100 ft/min and forwars speed very slow, tottally dependent on visual cues. With time you'll get it, as you do when parking a car.