Recirculation: Comments? Experiences?

[VH mick]

Looking for comments, experiences in regards to recirculation with landing a helo in a tight area surrounded all sides by factory walls and high fences.

thanks in advance.

Mick

[Flying Bull]

Better look for another landingsite.
There have been several accidents, where the downwash blew parts loose, i.e. roofpanels and so on.
The stuff isn´t build to withstand the downdraft of a helicopter.
You´re lucky, if only the helicopter breaks....
I remember a rescue BK117 crash 2005 in Germany
http://www.idowa.de/donau-post/nachricht/nachricht.html?nachrichten_id=1466477;redaktion_id=5
Parts from the wall were blown loose and went through the rotor - and the building was only to one side!!!!
Another accident happend only a few days ago
http://www.va-luftrettung.de/forum/showthread.php?t=2107
So better look for an apropiate landing site and walk 200 meters - a doc might even be faster at the scene of action because a quick landing some meters away takes much less time than a very slow and cautious decent in a confined area - not regarding the crashrisk!
Fly save - greetings Flying Bull

[Scissorlink]

Dont be too slow and cautious..more time you spend mucking around getting out of a confine worse the recirculation will be, one of the few cases when you want to get it light on the skids and then go, you have to be absolutely positive your not going to get stuck in no mans land with not enough power tho. Have experimented sitting in a tight confine in a hover with the torque guage in the green then as its all started to circulate the torque goes up real fast..Coming in it's a fine line between Vortex ring state and recirculation, come in over the lowest point if you can and keep edging forward as far as you can, sometimes you just gotta pick the lesser evil in regarding wind direction etc


SL

and do make sure nothing can get blown around

[TheFlyingSquirrel]

I think it can be worse with a large building on just one side. I remember once being sucked towards the hanger wall at an alarming rate with a good measure of opposing cyclic in too !:uhoh:

[VH mick]

Just an update for anyone interested. Landed safely without any signs of recirculation :). Machine was an R-44 and area was approx 3 R-44's wide and 3 R-44's long. Kept machine light as possible and not too slow as stated by scissor link. Thanks again for the input.

Mick