Rescue heli causes ice to form on wing of ditched A320?

[mickjoebill]

One of the passengers said he was standing on the wing and had no problem
until a helicopter hovered overhead. That splashed water onto the wing and
the water immediately froze. Several then lost their footing. A lady next
to him started to slip into the water because of this new ice. He and
another man grabbed her, but almost followed.



Is such ice forming (if true) a rare phenomena in helicopter operations?


Mickjoebill

[zalt]

An airliner ditches into a river in one of the most densely crowded cities on earth after an apparent bird strike and every one survives....

and you what to know if a helicopter forming ice on the wing of this airliner floating in the river is RARE??

[SASless]

Now for once....me and Zalt are firmly in agreement here!:uhoh:

I guess we have to define "rare"....to be able to answer this question.

But.....a wild assed guess would suggest this is not a real problem on a daily basis in the helicopter world.:ugh:

Now I would suppose any helicopter pilot worth is salt would not have approached the downed airliner floating in an icy river if he thought the rotorwash would slosh water up on the wing and cause ice to form....but as the airliner was sinking all the while and people were standing up to their knees in that same icy water....perhaps we can forgive this pilot for that temporary inconvenience to those he was about to winch up.


http://d.yimg.com/us.yimg.com/p/ap/20090116/capt.397c5c78282e497989c651b4a778a34b.aptopix_new_york_plane _in_river_nydp109.jpg?x=400&y=264&q=85&sig=Jb05lR9fIwqU8eGebKwcFg--

[Phil77]

The helicopter in question was the NYPD's 412; I too was a bit concerned at first about the effect off his downwash until I saw that he was deploying a rescue diver. He actually aborted a first attempt, backed out and came in from the opposite direction (presumably to deploy the diver down- not upstream from the floating plane).

The diver(s) actually did pull a couple of victims out of the frigid waters, so I guess the inconvenience for the rest was justified after all.

[mickjoebill]

An airliner ditches into a river in one of the most densely crowded cities on earth after an apparent bird strike and every one survives....

and you what to know if a helicopter forming ice on the wing of this airliner floating in the river is RARE??

I wasn't asking if all the circumstances of the crash were rare (!) I am interested if it is rare for down draft and spray to cause ice on (any) structures below.



Mickjoebill

[the beater]

I don't suspect that you'll find any statistics on this - as others have noted, the circumstances are unusual.
But; common sense says that if you have very cold water splashed by rotor downwash, or indeed any other means, onto a sub-zero temperature surface, it's going to freeze.
Am I missing something? as this seems too simple a question to answer.

Standing-by to be flamed (as usual).

[mickjoebill]

I don't suspect that you'll find any statistics on this - as others have noted, the circumstances are unusual.

Surely spray hitting a very cold surface isn't that unusual?
Those that work near frigid water may be able to shed some light?

The point of asking the question is to figure out if the forming of ice was coincidental to the heli appearing.


Mickjoebill

[airborne_artist]

Surely spray hitting a very cold surface isn't that unusual?

A constant problem for the convoys supplying the Russian Arctic ports in WWII. Ships capsized because of ice on the upper surfaces formed by sea-spray.

[Bladecrack]

MJB,

I understood what you were trying to get at from your original question pal, but you have to expect the typical sarcastic responses before you get one or 2 replies that are of some help, this is pprune after all :p

BC

[the beater]

Ahh.:O








































more characters, as required.

[Brian Abraham]

Is such ice forming (if true) a rare phenomena in helicopter operations?
Certainly some thing for those engaged in rescue operations in cold climates to think about, but I'd guess they are in the most part aware of the issue. One piece of film of the 320 moored against the wharf showed it to be surrounded by ice floating on the water, so it was sure cold.

[Bladecrack]

I noticed that too Brian, certainly as Mick says the effect of the downwash chilling the water to form ice is an interesting phenomenon, kind of like an earlier thread that showed the downwash of a B205 creating fog in the right conditions..

BC