For confined areas I use a simple checklist listed below and there is a brief description of each item.

PWOTFEEL


P)ower – from your performance charts determine if you have enough power to hover at the intended point of landing

W)ind – determine wind direction. Do a high recon at 500 agl above the highest obstacle in the area. Circle around the landing zone, fairly tight, keep the radius equal, you will need the steepest bank downwind to hold the radius constant as your groundspeed is at the highest, least bank when you are into a headwind. Also, check for blowing smoke, ripple signs on lakes, the wind cause ripples on the downwind side of the lake.

O)bstuctions – remain 500 agl above the highest obstruction in the area as you circle. This is the high recon, look for other obstructions. Wires are hard to see so look for poles, towers as these are signs that wires are present.

T)urbulence - think about turbulence you may encounter in the area and its possible causes, buildings, treelines, etc.

F)orced Landing areas – if the engine quits know where can you put it down.

E)ntry - from the high recon circling you plan a downwind leg, base, and final. These legs can be adjusted to avoid obstacles, turbulence, lack of forced landing areas. You want a good approach into the landing area and into the wind. Know where the landing zone is, remember landmarks around it because if the terrain is uneven you may lose sight of it on final approach.

E)xit – from the high recon you would have a plan for exiting. Your exit path should avoid obstacles, be into the wind, have forced landing areas,etc.

L)anding zone - on final do a low recon, recheck for wires, poles fences, bushes. If things don’t look right or there are surprises then go-around.

Lots of good information here. I can only add one thing. It's a question to all of you fretting over how to determine wind direction: Which way would you land if the engine quit? Do we mean to say that helicopter pilots are flying around oblivious to the wind direction?

What kind of weather system are you under? Which way was the wind blowing at departure? Why weren't you keeping track of it? When we're flying, one of our primary jobs is to know where the wind is. And if there's enough of it to make a difference, you better know it. This is especially true if you depart someplace *knowing* that you're headed for a site landing.

Lecture mode: OFF

To Muffin: All things considered, in the site you described, I'd prefer to land with a headwind and depart with a tailwind. I do not like to land directly downwind, especially to a confined area due to the obvious worry of VRS/SWP. Yes, it can be done safely, but it is far too risky for far too long a period of time. Taking off downwind is also risky, but if you have sufficient power, the exposure can be limited if you can turn back into the wind (or at least crosswind) as soon as possible. Just remember, the only absolute is that you must not crash.

PPRUNEFAN#1,

I take it you fly singles by your reference to "the" engine failure situation, perhaps mainly VFR at relatively low altitudes? In that case you are well advised to be constantly aware of the wind at all times and will have visual clues to help you, but be aware that there are a number of reasons why other pilots might not be as constantly aware of the precise local surface wind as you obviously are - and it doesn't make them bad people.

For example, even in UK, some aircraft transit IFR at relatively high altitudes up to 100 miles or more to a landing site involving a confined area at the destination. Pilots in this situation cannot rely on the wind on the ground being the same as as the departure point and would be stupid to do so! As a single engine failure in transit in a multi engined helicopter would not be so demanding, it's not a major priority to be constantly aware of the precise local surface wind en route. Obviously it is a requirement to keep a mental picture of the GENERAL wind direction though, in order to navigate.

It can be difficult to keep track of the precise surface wind direction by simple means when the aircraft is IMC. ATIS or ATC reports can be misleading when the nearest airfield lies some distance away from the actual destination because LOCAL effects can cause major wind direction variations. One of our regular landing sites is a confined area adjacent to the corner of a very large building. It is quite common for there to be a difference of more than 90 degrees between the surface wind directions on adjacent sides of the building...and quite different from what the nearest ATIS, nearly 20 nm away, is giving.

We always have to be ready to be surprised by the actual surface wind direction on arrival at a remote LS, hence the need for a good site recce on arrival.

BTW, Performance A / Class 1 vertical takeoff profiles often lay down crosswind limits and do NOT usually allow downwind arrival or departures so it can be a little more involved than, as you put it: "the only absolute is that you must not crash". :)

As I think someone said earlier, wind direction can vary locally quite a lot, especially in mountainous or even hilly areas. I live in Wales; I learned that fairly early on.

Flying a circuit/orbit at around 35 kts will definitely give you the wind direction, as I discovered recently when trying to do something totally different. A local landowner wanted to put three 300 ft wind turbines on his land on a hill about a mile from my home, and I was part of the local campaign against it. "Officially" it was said that the turbines wouldn't be visible from most of the area; we thought otherwise. Someone suggested flying a balloon above the site at 300 ft, but we didn't have access to a balloon, and couldn't work out how to arrange it. The conversation which followed then went like this:
Me (waking up): I'm a helicopter pilot.
Committee member: You're a WHAT?!!!!!
2nd Committee Member: Helicopter pilot? Who's a helicopter pilot?
Me: I am.
Stunned silence.

Anyway, I offered to circle over the site of the three turbines, at 300 ft, while people positioned themselves strategically around the valley with cameras. I said I'd have to do it on a non-windy day to have any hope of keeping both my position and altitude with any accuracy, and if any people or cars appeared I'd have to leave. Amazingly, such a day dawned the following weekend, and I took off, knowing that even at 700 ft approx (300 ft above the proposed turbine site) the wind would only be around 10 kts. Well, flying exactly over that field was extraordinarily difficult; I just felt like I was being blown off it. And I knew exactly which way the wind was coming from after very few orbits. A useful lesson.

In case anyone's interested, they did get the photos, and the application was refused, though I don't think my flight actually made much difference. I had fun doing it though. :)

Randy_g

Please can you explain what you mean by this bit -

"To find the wind, slow to 35-40 kts, and fly in trim (very important) by the confined area one way, then reversed. If a x-wind, your nose will point to it's direction (if you are in trim)."

If you are suggesting that the helicopter will behave like a wind-vane while flying in free air then I feel an interesting discussion coming on! :)

Cheers

TeeS

I can't see what the discussion would be about. That's how every helicopter flies (except maybe ones with conter-rotating main rotors).

:rolleyes:

ShyTorque:
Pilots who fly twin-engine IFR helicopters generally are professionals who know how to gauge surface wind and don't need advice from amateurs. Conscientious IFR pilots will monitor the ATIS at nearby airports whilst in cruise to keep track of the local surface winds.

Amateurs who do need advice on determining surface wind generally won't be flying sophisticated IFR-capable, twin-engine aircraft.

Ergo...

RobboRider

If Randy_g is suggesting that you fly along a track line and see which direction you have to point the nose to maintain track then I fully agree. However, what I think he is saying is that as you fly along at low speed and in balance, the tail will be blown downwind and point the nose of the aircraft into wind. If that is the case we will have to disagree!

Your helicopter (or glider, 747 etc.) has no conception of wind when it is flying because it is flying in that parcel of air that is the wind! It is only when we look out of the window at the ground that our brains get confused and tell us that the aircraft is handling differently when flying into wind or downwind. The sensation is at its greatest when at low level because when flying downwind the groundspeed is so much higher than expected. The tendency is to slow the aircraft down to make the picture fit and that is when it all goes pear shaped.

TeeS

PPRUNE FAN #1,

Ergo we ALL need to do a proper recce including a careful wind assessment on arrival at a CA, amateur pilot or professional.

Points:

1. The Military confined area recce is Size, Shape, Surrounds, Surface, Slope in that order.

2. If you don't know the wind fly a suitable (cardinal) heading and note the drift left or right. Turn 270 degrees in the direction of drift ie if N was your first heading and you were drifting right, turn onto W. If you are now drifting left, the wind is between N and W in this example. If you are still drifting right the turn onto S and check drift again. Once you have narrowed the wind down to a 90 degree arc then split the difference and check drift again. Keep repeating until you fly on a hdg with no drift and you are into wind. This is the cloverleaf procedure and is much more longwinded than simply comparing airspeed to groundspeed.

3. Given a choice between a downwind approach and a crosswind approach I would take crosswind. Given a further choice I would take the crosswind from the left in a helo with anticlockwise rotation (when viewed from above) because you are reducing Tq with right pedal.

4. Using cloud shadow movement as a guide to wind direction is frequently misleading because the surface wind will be different in strength and direction to the wind at the cloudbase.

5. All the confined area recce techniques in the world boil down to picking the best available approach path taking into account wind, obstructions, wires, sun position etc.. Can I get in? How will I get in/out.

TeeS You are correct in your second post. That is what I was saying, simply put, the crab angle shows which side the wind will be blowing from. Sorry for the confusion. At the lower speeds, groundspeed differences are easier to see, and the crab angle will be greater. Didn't mean to infer that the a/c acted as a weathervane.

PpruneFan everyone should be aware of where the wind is during cruise, but winds at the surface can vary significantly from wind found at cruise altitudes. To anyone not sure how the wind reacts with obstacles, watch a stream pass by rocks, etc. That is a good way to visualise how the wind reacts.

I've seen wind on a lake come from either end at the same time, due to a small hill. Example; wind from the west, some goes around to the north, some to the south, some over the top, wind curves around hill and now comes from north, south, and west. Makes for an interesting approach.

Cheers

http://randyspics.tripod.ca/gifs/naughty.gif Randy_G

http://randyspics.tripod.ca/gifs/man...ers_sm_wht.gif

You folks in the UK are too technical for me. Here in the states while flying We use the P factor. That is if on a long cross country We have to find a place to P. Our rules are pretty simple, if your safe and not trespassing, go for it.........
Reverting to lesson one is that you should know how to fly in the first place......

I missed out, on purpose, the most interesting bit.

As a pre-cursor, on downwind to the area my instructor switched off the landing light "to make us less conspicuous" - I asked if that was a bit pointless seeing as we're a noisy helicopter !

Anyhow we got in, got out, and on Monday I got a phone call. "We've had a complaint . . ." - someone said they'd seen us land, and the noise had made a horse bolt and injure itself. We're waiting for the outcome, but we both know we didn't land even if we did come down very low before pulling vertical on the way out. Such is life !

Just a thought.

The military have many 'Low Flying Areas' used by helicopter crews to practice off airfield confined areas.

Can we use these areas?

Coupla more S's ShyT

Sun - when its low and can affect your vision.

Snow - is it hard packed, potential for white out?

rpRP,

I can understand Sun, BUT - SNOW!

Which part of the Caribbean are you in? :confused: :D

(It is allowed for in "Surface" anyway) :)

TB - nope! We are not limited by the 500' rule and most flying stations have local agreements with the landowners to use these areas - I believe on occasion money changes hands but don't quote me.
If you were to come to a private agreement with such a landowner it would be common sense to notify your CA practise by CANP or by phoning Ops at the local base just so you don't find yourself head to head with a Chinook.

Crab

RAF Shawbury is one such Helicopter Training Establishment with in excess of 100 civilian owned confined area and landing sites available for its use as part of the tri services training program.

To the best of my knowledge NO MONEY changes hands in exchange for that use. The landowners are a very pro 'Her Majesties Forces' section of the community and often take grief from their neighbours because of their support of helicopter training activities.

Without these areas, the level of training could be seriously affected (as discovered during Foot & Mouth outbreak). Please do not infer we would only support our armed services in exchange for money. !.....................However, for a day at the Base and a fly round, I'll go find some more willing landowners. :D

I can confirm that no money changes hands. DHFS Shawbury use my field behind the house for landing practice about once per week. The payback is a day out there once a year with a chance to fly one of their Squirrels plus a tour and a very nice lunch.

My neighbours love it, as all the kids and most of the adults come out to wave if they are around. The only time they don't use it is if there are horses in the field while they are on approach, although the horses actually ignore them completely.

Bladeslapper - I know, I've been in most of them. The jocular aside about money changing hands obviously hit a nerve!!!

No we don't pay you for the CAs, instead we use taxpayers money inviting you to a p*ss-up and a fly round in a Squirrel!