Any secrets to share?? Transitioning to hover...

[TZeer]

As title says.

Does any of you out there have any secrets to share when moving from forward flight to hover?

I have noticed there is a very "sudden" change in aerodynamics when moving from forward flight to hover, and I feel the need for input on the yaw changes very abruptly when moving into hover. I have no way of knowing if this is real or not, but I guess it would be normal to a point, as you will need more collective/torque to compensate for lift lost as speed slows down, and will again transfer to more rotational forces on the helicopter.

Holding in the FTR works to certain degree, but at some point in the envelope, maybe around 15-30 knots, it seems as someone "pulls a rug" out under you. And the yaw starts kicking out.

So far I have moved my pedals in small increments and trimmed as I have moved through the envelope. This way I leave most of the work to the SCAS and only "refreshing" it's trim to keep the YAW from saturating. But I'm dependent on the joystick overview for that method to check that the YAW is not getting close to the saturation level, kinda breaks imersion.

I'm using virpil stick, collective and pedals. My pedals are modified with a dampener mod, so no re-center to trim. So in theory I should have everything I place to get this as smooth as possible. I don't have any curves on the collective or pedals.

I have no problem in hover. I can sit stable forever if I want to, without engaging Hover Hold sub mode. It's just the transition into hover I'm wondering i'm overlooking something basic.

Is it down to me and my lack of skills? Or is it a combination with the unfinished FM?

[[DE] T-Bone]

29 minutes ago, TZeer said:

As title says.

Does any of you out there have any secrets to share when moving from forward flight to hover?

I have noticed there is a very "sudden" change in aerodynamics when moving from forward flight to hover, and I feel the need for input on the yaw changes very abruptly when moving into hover. I have no way of knowing if this is real or not, but I guess it would be normal to a point, as you will need more collective/torque to compensate for lift lost as speed slows down, and will again transfer to more rotational forces on the helicopter.

Holding in the FTR works to certain degree, but at some point in the envelope, maybe around 15-30 knots, it seems as someone "pulls a rug" out under you. And the yaw starts kicking out.

So far I have moved my pedals in small increments and trimmed as I have moved through the envelope. This way I leave most of the work to the SCAS and only "refreshing" it's trim to keep the YAW from saturating. But I'm dependent on the joystick overview for that method to check that the YAW is not getting close to the saturation level, kinda breaks imersion.

I'm using virpil stick, collective and pedals. My pedals are modified with a dampener mod, so no re-center to trim. So in theory I should have everything I place to get this as smooth as possible. I don't have any curves on the collective or pedals.

I have no problem in hover. I can sit stable forever if I want to, without engaging Hover Hold sub mode. It's just the transition into hover I'm wondering i'm overlooking something basic.

Is it down to me and my lack of skills? Or is it a combination with the unfinished FM?

No secrets, just watch these videos and practice until you get it right. Helicopter flying requires continuous training.

AH-64D Deceleration to an OGE Hover



 

[Floyd1212]

How much time/space are you giving yourself to transition?

There's the "slow and smooth" approach, which should mean gradual adjustments all the way to hover over a longer deceleration, but shouldn't be too much drama.  And then there's the "stand it on its tail" approach, which requires large amounts of collective and pedal right at the end as you are coming to a stop.

I personally do a trim reset before starting the transition, and don't trim again until settled in the hover.  This is not the recommended method, but that is the way my muscle memory is set, and holding the FTR during the whole transition would be a much different feel.

[UncleStains]

Think about transition from forward flight to hover as a series of discrete steps. As you practice the steps get smaller and it becomes a smooth curve. Start with IHADSS cruise symbology up so you can reference pitch angle and keep an eye on velocity/acceleration cues. Make sure your total weight is within OGE hover limits for practice.

I hold the trim reset throughout this process. Not sure if that's the correct technique, but it seems to work.

Start decelerating by pitching back to about +5 degrees (line of sight cross sitting on top of horizon cue). This pitch increase makes you slow down and gain altitude. Counter the ascending altitude by lowering the collective. Hold that +5 degree attitude with the cyclic and use the collective to get your vertical speed back to zero. I find it easier to watch how the flight path vector is moving rather than focusing on the vertical speed indicator. Once you're stable there, pitch back a little more to increase your horizontal deceleration rate. Counter your increasing altitude by further lowering collective.

Practice getting from 120 kts to 40 kts airspeed while maintaining constant altitude. Once you have that mastered, start getting slower.

Around 30 kts airspeed, it gets tricky. As your airspeed approaches the translational lift limit your vertical speed will start going negative. Pull the collective back up to counter this sinking. Keep managing vertical speed with the collective while you use the cyclic to nose down back to +5 degrees. This +5 degrees is the Apache's hover attitude (it happens to be exactly the same as the Apache's attitude when sitting on the ground).

Once your airspeed is down to around 10 kts, switch the IHADSS to hover symbology and start thinking in terms of ground speed. The hover symbology velocity and acceleration cues reference ground speed, not airspeed. Get the velocity and acceleration cues inside the line of sight cross, release the trim reset, and switch on attitude hold. Then stabilize your vertical speed with the collective and switch on altitude hold.

While all of the above is happening, you need to balance your collective movements with pedal movements. Raise the collective, left pedal....lower the collective...right pedal. Eventually it becomes automatic and you'll find yourself moving your feet in anticipation of those collective movements.

As virtual pilots, we don't get the feedback of feeling the horizontal and vertical acceleration. This means you really have to stay ahead and anticipate what each control movement is going to do to your attitude/altitude/heading/speed and make the necessary adjustments to the other controls to compensate.

As you progress, try to stay in aerodynamic trim (ball centered) above 40 kts then switch to nose-to-tail trim (flight path vector in front of aircraft nose) as you come to a stop. Do all this practice over an airport so you can easily gauge your heading and ground track. Next, find some hills or buildings and practice stopping in a hover while masked behind them.

[Tom P]

As someone posted, watch brad's video, dude is a real life 64 pilot and was an 64 instructor pilot. 

If I were to give any "secret" it would be to watch your rate of climb as you bring down the collective and start to pull back on the cyclic and trim as you slow down. In DCS you can drop the collective to around 30% and still have positive flight while slowing down. if your rate of climb starts dropping fast slowly pull some collective to keep the rate of climb in a controlled state so you don't fall like a rock. Remember it's not going to stop on a dime. 

[TZeer]

A lot of good feedback here

Will try and put it into practice.

My approach to this is usually "slow and smooth" as @Floyd1212 mentioned. And I don't have much trouble with the lift or loosing it as I transition. It's more of the sudden kick/extra input needed on the yaw in the envelope. When I smooth that out, I'm golden

[mason.zh]

13 hours ago, TZeer said:

I feel the need for input on the yaw changes very abruptly when moving into hove

My guess is the Heading Hold mode kicks in. If you open the control input by RCtr + Enter you should see 2 blue lines around the yaw indicator, if yaw changes very abruptly while you are slowing down, I assume you should see 2 things in the control input for the yaw axis: 1) blue line around yaw axis 2) green line bouncing around. 

What I did to solve this was to either hold the FTR button, which makes the helicopter less stable, or "break out" the heading holding. In the manual page 179 you will find the heading hold engage conditions, one of these conditions is `Pedal displacement <= 3% in yaw axis from the force trim reference position.` This means if you are below 40 knots and move the pedals away from the previously trimmed position far enough, then the heading hold should not be engaged.  Without heading hold there should be no abrupt yaw changes during the approach, especially when you reach 40 knots or lower. 

13 hours ago, TZeer said:

So far I have moved my pedals in small increments and trimmed as I have moved through the envelope.

So my suggestion is, you can trim the helicopter to perhaps 50 knots, and from there stop trimming, once you established a stable hover, trim again. If you watch Brad's video you will also find at some point during the approach he stops trimming and just flight the helicopter. According to the manual:" a 'breakout' value within each flight control axis of the cyclic and pedals allows the pilot to 'fly through' the hold modes" 

This is a video I recorded a long time ago, you will see once my speed is below 40kts the heading hold mode kicks in, but instead of moving the pedals to the left and trim, I breakout the heading hold mode by moving the pedals away from the previously trimmed position. 

https://www.youtube.com/clip/Ugkxf4WeNENy5jWFJkL-UW_jBLfl-f_XGRPl

[Dangerzone]

Not sure if this has been mentioned, but one tip is when first taking off - try hovering out of ground effect. Note the power that's required to maintain that hover OGE. This is the power that will be required when you come back into a hover OGE. (Or conversely if you plan on hovering in ground effect, do the same). 

That way, before the helicopter settles, you'll know what power setting you need to be on in order to stop it settling.