Dust approach and landing.
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Dust approach and landing.
Hi,
I need any help with SOP's or any other info on Dust (Brownout) procedures. With specific referance to the Hover meter.
Any help with procedures about appraoches and landings into dust or even snow will be great.
I need any help with SOP's or any other info on Dust (Brownout) procedures. With specific referance to the Hover meter.
Any help with procedures about appraoches and landings into dust or even snow will be great.
Using the technique of a running landing (provided surface is suitable) will make sure dust particles blown up by your downwash remain behind the aircraft during the landing sequence.
Zero-zero's work aswell if the surface is not suitable for running landings. However they're not as good as keeping dust behind you just before you touch-down. If you have found you are comming in a little fast, watch flaring just before you land, this will kick it all up right in front of you.
TiP
Zero-zero's work aswell if the surface is not suitable for running landings. However they're not as good as keeping dust behind you just before you touch-down. If you have found you are comming in a little fast, watch flaring just before you land, this will kick it all up right in front of you.
TiP
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From what I remember from snow landing training, the most important thing is picking a decent hover reference.
Obviously, when you get into the last stages of the landing, all you are going to see is white or brown, depending on whether you are doing snow or dust landings. What you need is something of known size that you can land right next to without it blowing away, so you can use it to see you are not drifting before you put your skids/wheels on the ground. Depending on the size of your aircraft, and what you have available, you can use a vehicle, a bergen, a person kneeling down (pre-briefed, so he doesnt run away in fear that you are going to land on him), or if there is no-one on the ground at the LS, use a large rock, small tree or similar. The idea is to do a zero/zero landing with this reference right by your right foot (assuming you are flying from the Right Seat), so it is the one thing you can still see in the re-circ. Dont use a fence post or similar, as you can drift around it in a circle without seeing a change of aspect.
Believe me, it takes practice before you get it right - expect to overshoot, and do it sooner rather than later!
Obviously, when you get into the last stages of the landing, all you are going to see is white or brown, depending on whether you are doing snow or dust landings. What you need is something of known size that you can land right next to without it blowing away, so you can use it to see you are not drifting before you put your skids/wheels on the ground. Depending on the size of your aircraft, and what you have available, you can use a vehicle, a bergen, a person kneeling down (pre-briefed, so he doesnt run away in fear that you are going to land on him), or if there is no-one on the ground at the LS, use a large rock, small tree or similar. The idea is to do a zero/zero landing with this reference right by your right foot (assuming you are flying from the Right Seat), so it is the one thing you can still see in the re-circ. Dont use a fence post or similar, as you can drift around it in a circle without seeing a change of aspect.
Believe me, it takes practice before you get it right - expect to overshoot, and do it sooner rather than later!
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Cant help with that, I'm afraid. Sounds like a bad idea to me: at some stage you are going to have to put your wheels/skids on the ground, and when you do, you are going to need to be looking outside with a decent reference, so you can tell that you are not sinking one one side. You dont know whats under the snow - could be a tree, a rock, a soft drift, whatever. For the same reason, you are best to do this multi-crew, so someone can look out on the left and see what sticks out underneath the cab on that side when you blow the dust/snow away.
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PC-PLOD has a importen point, if doing these kinds off approaches, on a regarlly basis, do it multi crew.
Another point to consider is; come into the hover just above the "snowball", (app. 2 times roter diameter) if you stay there for a minute or two you might blow your landing area free of snow. I have no experince doing sand/dust app.!!!
Be carefull.
Another point to consider is;
come into the hover just above the "snowball", (app. 2 times roter diameter) if you stay there for a minute or two you might blow your landing area free of snow. I have no experince doing sand/dust app.!!!Be carefull.
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Dust/snow
I have spent quite a bit of time in dust and snow, so here is my tuppence! The amount of recirculation can vary hugely depending on the thickness of the sand or temp of the snow, but the technique doesnt vary too much. If it is light then it can be blown away from a highish hover. However, I would usually prefer to stick to a known method.
I will do a good recce first, especially noting wind, pick good markers - both for your approach, but also for your overshoot. Pick a good clear route out for you overshoot and note the heading, and brief it. Most importantly of all is a good solid marker on the ground to approach to. This needs to be fixed, and not likely to blow away. If you it is a pre-arranged LS, get someone to put a marker down for you before. A tractor tyre, a gerry can full of water, a couple of building blocks - all good markers. If you cant get that improvise. A small shrub/bush, a log whatever. I have used tracks at times. There is usually something - even in the desert. Set up for a gentle decelerative approach to aim to land zero/zero, with minimum flare. If you have time - give yourself 2-300 ft and set up your approach. The dust cloud will generally start to bulid up at a height of 2-3 times your rotor diameter. At that point you want to be still going forward, with gradual deceleration. If in doubt go a practice a load first without dust. Fly down to your marker, and NEVER lose sight of it. Imagine a fixed line from it to you pulling you down that line. It wants to be right in front of your right foot when you touch down (if in right seat). If you lose your marker - overshoot straight away, and set up again in your own time. Dont be rushed into it. If you brown out - straight to instruments. AI - wings level- maybe slight (very slight) nose down, and apply power positively to get you away from the ground. Remember your overshoot heading. You should be climbing forward by now. Stick witht he instruments until you are clear of the cloud. Too many people have stacked it by letting the nose drop, and ploughing into the ground.
Overall, everyhing needs to be smooth, gentle movements. Nothing harsh, especially at the end. Avoid flaring - accept a slight run off if you can. Most importantly - if you dont like it overshoot early - no shame in that. Much better than explaining why you tried to push on in a brownout!
I will do a good recce first, especially noting wind, pick good markers - both for your approach, but also for your overshoot. Pick a good clear route out for you overshoot and note the heading, and brief it. Most importantly of all is a good solid marker on the ground to approach to. This needs to be fixed, and not likely to blow away. If you it is a pre-arranged LS, get someone to put a marker down for you before. A tractor tyre, a gerry can full of water, a couple of building blocks - all good markers. If you cant get that improvise. A small shrub/bush, a log whatever. I have used tracks at times. There is usually something - even in the desert. Set up for a gentle decelerative approach to aim to land zero/zero, with minimum flare. If you have time - give yourself 2-300 ft and set up your approach. The dust cloud will generally start to bulid up at a height of 2-3 times your rotor diameter. At that point you want to be still going forward, with gradual deceleration. If in doubt go a practice a load first without dust. Fly down to your marker, and NEVER lose sight of it. Imagine a fixed line from it to you pulling you down that line. It wants to be right in front of your right foot when you touch down (if in right seat). If you lose your marker - overshoot straight away, and set up again in your own time. Dont be rushed into it. If you brown out - straight to instruments. AI - wings level- maybe slight (very slight) nose down, and apply power positively to get you away from the ground. Remember your overshoot heading. You should be climbing forward by now. Stick witht he instruments until you are clear of the cloud. Too many people have stacked it by letting the nose drop, and ploughing into the ground.
Overall, everyhing needs to be smooth, gentle movements. Nothing harsh, especially at the end. Avoid flaring - accept a slight run off if you can. Most importantly - if you dont like it overshoot early - no shame in that. Much better than explaining why you tried to push on in a brownout!
109er - if you are seriously going to try landing in dust using a doppler hover meter, you are probably going to crash. Trying to hover on a doppler meter can be very disorientating and you need a very good instrument scan to select and maintain a hover attitude IMC, and a rad alt. It is very easy to drift so you need a wide-open space to do it with no trees or obstacles to bump into. You are better off using a zero-zero type visual arrival which will work as long as there is more than a few knots of wind - if it is calm then a running landing is the only way to stay clear of the dust cloud. Whereas a light covering of snow will blow away leaving a crust - the dust just keeps on coming.
You don't say why you want to try this but I wouldn't bother if I were you - I've been IMC in dust a few times and it is V scary.
You don't say why you want to try this but I wouldn't bother if I were you - I've been IMC in dust a few times and it is V scary.
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It's a good idea to get used to seeing how the "dustball" forms behind the helicopter then advances as you slow. If you get into a low hover taxi regime with sufficient airspeed, the dustball will be behind the helicopter. Progressively slow the helicopter and see it advance forward. When it is the furthest forward with which you are comfortable, that is the airspeed you'll need to run on. Consider visual reference, passenger comfort, as well as what is going in the intakes to determine how much dustball you're comfortable with.
With a shallow approach to a run-on or no-hover landing, if you maintain a slow rate of deceleration then when you experience a brown-out all you need is slight forward cyclic and just enough power to maintain level. This is because the brown-out occurred due to the dustball moving too far forward. Catch it early and you accelerate slightly to move it aft.
Of course if you have no idea what is in front, power to climb is required, but that much power exacerbates the conditions.
_____________
As far as using the hover meter, I agree with the above that it leads to bad things for a landing. However, if you set it up before hand and the crew is trained to respond to it, it can be a life saver during an overshoot due to a full loss of visual reference. Establish a rate of climb, select the overshoot heading, zero the lateral drift and maintain a forward acceleration. The last two points need visual references or a hover meter.
With a shallow approach to a run-on or no-hover landing, if you maintain a slow rate of deceleration then when you experience a brown-out all you need is slight forward cyclic and just enough power to maintain level. This is because the brown-out occurred due to the dustball moving too far forward. Catch it early and you accelerate slightly to move it aft.
Of course if you have no idea what is in front, power to climb is required, but that much power exacerbates the conditions.
_____________
As far as using the hover meter, I agree with the above that it leads to bad things for a landing. However, if you set it up before hand and the crew is trained to respond to it, it can be a life saver during an overshoot due to a full loss of visual reference. Establish a rate of climb, select the overshoot heading, zero the lateral drift and maintain a forward acceleration. The last two points need visual references or a hover meter.
I have witnessed Russians landing their Mi8 AMT in thick snow at many occasions.
They used to do at least one low/slow pass over the landing spot to check wind and blow as much snow as possible and then, were performing a normal approach, ended by a higher hover than usual. At one stage, on short final, flight engineer, seated behind and between the pilots, begun to give doppler informations untill the landing .
This was looking nicely organised in terms of task sharing, but training and snow experience was obviously also behind all of this.
The auto-pilot was said to be very good, and there was no doppler coupling on hover mode on this model.
They used to do at least one low/slow pass over the landing spot to check wind and blow as much snow as possible and then, were performing a normal approach, ended by a higher hover than usual. At one stage, on short final, flight engineer, seated behind and between the pilots, begun to give doppler informations untill the landing .
This was looking nicely organised in terms of task sharing, but training and snow experience was obviously also behind all of this.
The auto-pilot was said to be very good, and there was no doppler coupling on hover mode on this model.
I used to overfly the site slowly to blow away some, drop a rucksack ( heavy ) out of the door then make the approach to the ruckcack putting it right up against the skid.
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OK guys here's the beef.
I have some multi-crew experience into dust with the Oryx(Super Puma) where we used the Doppler Hover Meter as as part of your scan in case you do loose visual and if landing was absolutely nessesary. You would usually loose visual only from about 15-20' in the worst cases. Then you would trasfer your scan inside using the Hover meter to asses drift, the ADI for attitude and the Radio Alt for hight and ROD. But also landing slighty more possitive than usual. But it's NOT that this would be a common practice. It would only be done ,as I said, when a landing was absolutely nessesary.
Now I'm operating the A109. It has Doppler hover meter, Auto Hover, App to the Hover, 4 Axis Autopilot, but we operate it single Pilot, and sometimes with a flight engineer. So I was trying to get Input from someone with some experience to adapt the current Multi-crew SOP's that I have for Single pilot Ops.
I must again state that this is only done in EXTREME conditions.
I have some multi-crew experience into dust with the Oryx(Super Puma) where we used the Doppler Hover Meter as as part of your scan in case you do loose visual and if landing was absolutely nessesary. You would usually loose visual only from about 15-20' in the worst cases. Then you would trasfer your scan inside using the Hover meter to asses drift, the ADI for attitude and the Radio Alt for hight and ROD. But also landing slighty more possitive than usual. But it's NOT that this would be a common practice. It would only be done ,as I said, when a landing was absolutely nessesary.
Now I'm operating the A109. It has Doppler hover meter, Auto Hover, App to the Hover, 4 Axis Autopilot, but we operate it single Pilot, and sometimes with a flight engineer. So I was trying to get Input from someone with some experience to adapt the current Multi-crew SOP's that I have for Single pilot Ops.
I must again state that this is only done in EXTREME conditions.
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I don't know the A109 too well, but in general, this is what I'd do.
1. Overshoot.
2. If you can't overshoot, engage the autopilot to stabilize in the hover (this should be set up in advance and only used if you have the confidence that the autopilot won't jump and that you will hit the right buttons). From here, you dial your altitude down to zero, or if that isn't possible. once stable you have time to think about how you'll land.
3. If you can't use the autopilot or overshoot, you'll have to use the AI to fly a hover attitude. Maintain height (radalt) until you have eliminated all drift, then slowly descend.
This is one of those sequences that people talk about and practice, but should never have to use. Landing in dustballs/snowballs is something that you don't manage at the time, but plan for in advance. If you plan properly, you will be able to overshoot. If you plan on using the other two steps above, you will run out of luck eventually.
1. Overshoot.
2. If you can't overshoot, engage the autopilot to stabilize in the hover (this should be set up in advance and only used if you have the confidence that the autopilot won't jump and that you will hit the right buttons). From here, you dial your altitude down to zero, or if that isn't possible. once stable you have time to think about how you'll land.
3. If you can't use the autopilot or overshoot, you'll have to use the AI to fly a hover attitude. Maintain height (radalt) until you have eliminated all drift, then slowly descend.
This is one of those sequences that people talk about and practice, but should never have to use. Landing in dustballs/snowballs is something that you don't manage at the time, but plan for in advance. If you plan properly, you will be able to overshoot. If you plan on using the other two steps above, you will run out of luck eventually.
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When we do them out yonder, we do a flyover to check the landing area and find a reference point (like most people say), do a downwind then come in at about 40 knots or so and level at about 75 feet until the reference point is right about where a steep (>45 degree) approach would put you on it... flare to decel (10 knots is what we use but we also have big ole fluffy forgiving wheels) then a steep and quick decend to a running with no significant stabilization at a hover, brakes and you're done with a 5 or so foot run. Some guys decel continuously through the decent until the last second to give a very low foreward speed in the end.
We usually hit the ground right about when the dust is passing the nose, which gives a good reference until the end. Dust starts about halfway through the decel (the high altitude and speed mean no dust until the flare). If things get a little screwed up, you're already headed down to your known landing zone, and you're usually already low enough to maintain a ground reference.
-Mike
We usually hit the ground right about when the dust is passing the nose, which gives a good reference until the end. Dust starts about halfway through the decel (the high altitude and speed mean no dust until the flare). If things get a little screwed up, you're already headed down to your known landing zone, and you're usually already low enough to maintain a ground reference.
-Mike
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Make a zero speed touchdown (i.e. no hover), or with a slight forward speed, preferably where the slope matches the aircraft hover attitude, to expedite the landing. And never do it downwind! 
